1 /*
   2  * Copyright (c) 1997, 2022, 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 "cds/classListParser.hpp"
  27 #include "cds/classListWriter.hpp"
  28 #include "cds/dynamicArchive.hpp"
  29 #include "cds/heapShared.hpp"
  30 #include "cds/lambdaFormInvokers.hpp"
  31 #include "classfile/classFileStream.hpp"
  32 #include "classfile/classLoader.inline.hpp"
  33 #include "classfile/classLoaderData.hpp"
  34 #include "classfile/classLoaderData.inline.hpp"
  35 #include "classfile/classLoadInfo.hpp"
  36 #include "classfile/javaAssertions.hpp"
  37 #include "classfile/javaClasses.inline.hpp"
  38 #include "classfile/moduleEntry.hpp"
  39 #include "classfile/modules.hpp"
  40 #include "classfile/packageEntry.hpp"
  41 #include "classfile/stringTable.hpp"
  42 #include "classfile/symbolTable.hpp"
  43 #include "classfile/systemDictionary.hpp"
  44 #include "classfile/vmClasses.hpp"
  45 #include "classfile/vmSymbols.hpp"
  46 #include "gc/shared/collectedHeap.inline.hpp"
  47 #include "interpreter/bytecode.hpp"
  48 #include "interpreter/bytecodeUtils.hpp"
  49 #include "jfr/jfrEvents.hpp"
  50 #include "jvm.h"
  51 #include "logging/log.hpp"
  52 #include "memory/oopFactory.hpp"
  53 #include "memory/referenceType.hpp"
  54 #include "memory/resourceArea.hpp"
  55 #include "memory/universe.hpp"
  56 #include "oops/access.inline.hpp"
  57 #include "oops/constantPool.hpp"
  58 #include "oops/fieldStreams.inline.hpp"
  59 #include "oops/flatArrayKlass.hpp"
  60 #include "oops/instanceKlass.hpp"
  61 #include "oops/klass.inline.hpp"
  62 #include "oops/method.hpp"
  63 #include "oops/recordComponent.hpp"
  64 #include "oops/objArrayKlass.hpp"
  65 #include "oops/objArrayOop.inline.hpp"
  66 #include "oops/oop.inline.hpp"
  67 #include "prims/jvm_misc.hpp"
  68 #include "prims/jvmtiExport.hpp"
  69 #include "prims/jvmtiThreadState.inline.hpp"
  70 #include "prims/stackwalk.hpp"
  71 #include "runtime/arguments.hpp"
  72 #include "runtime/atomic.hpp"
  73 #include "runtime/continuation.hpp"
  74 #include "runtime/globals_extension.hpp"
  75 #include "runtime/handles.inline.hpp"
  76 #include "runtime/init.hpp"
  77 #include "runtime/interfaceSupport.inline.hpp"
  78 #include "runtime/deoptimization.hpp"
  79 #include "runtime/handshake.hpp"
  80 #include "runtime/java.hpp"
  81 #include "runtime/javaCalls.hpp"
  82 #include "runtime/javaThread.hpp"
  83 #include "runtime/jfieldIDWorkaround.hpp"
  84 #include "runtime/jniHandles.inline.hpp"
  85 #include "runtime/os.inline.hpp"
  86 #include "runtime/osThread.hpp"
  87 #include "runtime/perfData.hpp"
  88 #include "runtime/reflection.hpp"
  89 #include "runtime/synchronizer.hpp"
  90 #include "runtime/threadIdentifier.hpp"
  91 #include "runtime/threadSMR.hpp"
  92 #include "runtime/vframe.inline.hpp"
  93 #include "runtime/vmOperations.hpp"
  94 #include "runtime/vm_version.hpp"
  95 #include "services/attachListener.hpp"
  96 #include "services/management.hpp"
  97 #include "services/threadService.hpp"
  98 #include "utilities/copy.hpp"
  99 #include "utilities/defaultStream.hpp"
 100 #include "utilities/dtrace.hpp"
 101 #include "utilities/events.hpp"
 102 #include "utilities/macros.hpp"
 103 #include "utilities/utf8.hpp"
 104 #if INCLUDE_CDS
 105 #include "classfile/systemDictionaryShared.hpp"
 106 #endif
 107 #if INCLUDE_JFR
 108 #include "jfr/jfr.hpp"
 109 #endif
 110 #if INCLUDE_MANAGEMENT
 111 #include "services/finalizerService.hpp"
 112 #endif
 113 
 114 #include <errno.h>
 115 
 116 /*
 117   NOTE about use of any ctor or function call that can trigger a safepoint/GC:
 118   such ctors and calls MUST NOT come between an oop declaration/init and its
 119   usage because if objects are move this may cause various memory stomps, bus
 120   errors and segfaults. Here is a cookbook for causing so called "naked oop
 121   failures":
 122 
 123       JVM_ENTRY(jobjectArray, JVM_GetClassDeclaredFields<etc> {
 124           // Object address to be held directly in mirror & not visible to GC
 125           oop mirror = JNIHandles::resolve_non_null(ofClass);
 126 
 127           // If this ctor can hit a safepoint, moving objects around, then
 128           ComplexConstructor foo;
 129 
 130           // Boom! mirror may point to JUNK instead of the intended object
 131           (some dereference of mirror)
 132 
 133           // Here's another call that may block for GC, making mirror stale
 134           MutexLocker ml(some_lock);
 135 
 136           // And here's an initializer that can result in a stale oop
 137           // all in one step.
 138           oop o = call_that_can_throw_exception(TRAPS);
 139 
 140 
 141   The solution is to keep the oop declaration BELOW the ctor or function
 142   call that might cause a GC, do another resolve to reassign the oop, or
 143   consider use of a Handle instead of an oop so there is immunity from object
 144   motion. But note that the "QUICK" entries below do not have a handlemark
 145   and thus can only support use of handles passed in.
 146 */
 147 
 148 static void trace_class_resolution_impl(Klass* to_class, TRAPS) {
 149   ResourceMark rm;
 150   int line_number = -1;
 151   const char * source_file = NULL;
 152   const char * trace = "explicit";
 153   InstanceKlass* caller = NULL;
 154   JavaThread* jthread = THREAD;
 155   if (jthread->has_last_Java_frame()) {
 156     vframeStream vfst(jthread);
 157 
 158     // scan up the stack skipping ClassLoader, AccessController and PrivilegedAction frames
 159     TempNewSymbol access_controller = SymbolTable::new_symbol("java/security/AccessController");
 160     Klass* access_controller_klass = SystemDictionary::resolve_or_fail(access_controller, false, CHECK);
 161     TempNewSymbol privileged_action = SymbolTable::new_symbol("java/security/PrivilegedAction");
 162     Klass* privileged_action_klass = SystemDictionary::resolve_or_fail(privileged_action, false, CHECK);
 163 
 164     Method* last_caller = NULL;
 165 
 166     while (!vfst.at_end()) {
 167       Method* m = vfst.method();
 168       if (!vfst.method()->method_holder()->is_subclass_of(vmClasses::ClassLoader_klass())&&
 169           !vfst.method()->method_holder()->is_subclass_of(access_controller_klass) &&
 170           !vfst.method()->method_holder()->is_subclass_of(privileged_action_klass)) {
 171         break;
 172       }
 173       last_caller = m;
 174       vfst.next();
 175     }
 176     // if this is called from Class.forName0 and that is called from Class.forName,
 177     // then print the caller of Class.forName.  If this is Class.loadClass, then print
 178     // that caller, otherwise keep quiet since this should be picked up elsewhere.
 179     bool found_it = false;
 180     if (!vfst.at_end() &&
 181         vfst.method()->method_holder()->name() == vmSymbols::java_lang_Class() &&
 182         vfst.method()->name() == vmSymbols::forName0_name()) {
 183       vfst.next();
 184       if (!vfst.at_end() &&
 185           vfst.method()->method_holder()->name() == vmSymbols::java_lang_Class() &&
 186           vfst.method()->name() == vmSymbols::forName_name()) {
 187         vfst.next();
 188         found_it = true;
 189       }
 190     } else if (last_caller != NULL &&
 191                last_caller->method_holder()->name() ==
 192                  vmSymbols::java_lang_ClassLoader() &&
 193                last_caller->name() == vmSymbols::loadClass_name()) {
 194       found_it = true;
 195     } else if (!vfst.at_end()) {
 196       if (vfst.method()->is_native()) {
 197         // JNI call
 198         found_it = true;
 199       }
 200     }
 201     if (found_it && !vfst.at_end()) {
 202       // found the caller
 203       caller = vfst.method()->method_holder();
 204       line_number = vfst.method()->line_number_from_bci(vfst.bci());
 205       if (line_number == -1) {
 206         // show method name if it's a native method
 207         trace = vfst.method()->name_and_sig_as_C_string();
 208       }
 209       Symbol* s = caller->source_file_name();
 210       if (s != NULL) {
 211         source_file = s->as_C_string();
 212       }
 213     }
 214   }
 215   if (caller != NULL) {
 216     if (to_class != caller) {
 217       const char * from = caller->external_name();
 218       const char * to = to_class->external_name();
 219       // print in a single call to reduce interleaving between threads
 220       if (source_file != NULL) {
 221         log_debug(class, resolve)("%s %s %s:%d (%s)", from, to, source_file, line_number, trace);
 222       } else {
 223         log_debug(class, resolve)("%s %s (%s)", from, to, trace);
 224       }
 225     }
 226   }
 227 }
 228 
 229 void trace_class_resolution(Klass* to_class) {
 230   EXCEPTION_MARK;
 231   trace_class_resolution_impl(to_class, THREAD);
 232   if (HAS_PENDING_EXCEPTION) {
 233     CLEAR_PENDING_EXCEPTION;
 234   }
 235 }
 236 
 237 // java.lang.System //////////////////////////////////////////////////////////////////////
 238 
 239 
 240 JVM_LEAF(jlong, JVM_CurrentTimeMillis(JNIEnv *env, jclass ignored))
 241   return os::javaTimeMillis();
 242 JVM_END
 243 
 244 JVM_LEAF(jlong, JVM_NanoTime(JNIEnv *env, jclass ignored))
 245   return os::javaTimeNanos();
 246 JVM_END
 247 
 248 // The function below is actually exposed by jdk.internal.misc.VM and not
 249 // java.lang.System, but we choose to keep it here so that it stays next
 250 // to JVM_CurrentTimeMillis and JVM_NanoTime
 251 
 252 const jlong MAX_DIFF_SECS = CONST64(0x0100000000); //  2^32
 253 const jlong MIN_DIFF_SECS = -MAX_DIFF_SECS; // -2^32
 254 
 255 JVM_LEAF(jlong, JVM_GetNanoTimeAdjustment(JNIEnv *env, jclass ignored, jlong offset_secs))
 256   jlong seconds;
 257   jlong nanos;
 258 
 259   os::javaTimeSystemUTC(seconds, nanos);
 260 
 261   // We're going to verify that the result can fit in a long.
 262   // For that we need the difference in seconds between 'seconds'
 263   // and 'offset_secs' to be such that:
 264   //     |seconds - offset_secs| < (2^63/10^9)
 265   // We're going to approximate 10^9 ~< 2^30 (1000^3 ~< 1024^3)
 266   // which makes |seconds - offset_secs| < 2^33
 267   // and we will prefer +/- 2^32 as the maximum acceptable diff
 268   // as 2^32 has a more natural feel than 2^33...
 269   //
 270   // So if |seconds - offset_secs| >= 2^32 - we return a special
 271   // sentinel value (-1) which the caller should take as an
 272   // exception value indicating that the offset given to us is
 273   // too far from range of the current time - leading to too big
 274   // a nano adjustment. The caller is expected to recover by
 275   // computing a more accurate offset and calling this method
 276   // again. (For the record 2^32 secs is ~136 years, so that
 277   // should rarely happen)
 278   //
 279   jlong diff = seconds - offset_secs;
 280   if (diff >= MAX_DIFF_SECS || diff <= MIN_DIFF_SECS) {
 281      return -1; // sentinel value: the offset is too far off the target
 282   }
 283 
 284   // return the adjustment. If you compute a time by adding
 285   // this number of nanoseconds along with the number of seconds
 286   // in the offset you should get the current UTC time.
 287   return (diff * (jlong)1000000000) + nanos;
 288 JVM_END
 289 
 290 JVM_ENTRY(void, JVM_ArrayCopy(JNIEnv *env, jclass ignored, jobject src, jint src_pos,
 291                                jobject dst, jint dst_pos, jint length))
 292   // Check if we have null pointers
 293   if (src == NULL || dst == NULL) {
 294     THROW(vmSymbols::java_lang_NullPointerException());
 295   }
 296   arrayOop s = arrayOop(JNIHandles::resolve_non_null(src));
 297   arrayOop d = arrayOop(JNIHandles::resolve_non_null(dst));
 298   assert(oopDesc::is_oop(s), "JVM_ArrayCopy: src not an oop");
 299   assert(oopDesc::is_oop(d), "JVM_ArrayCopy: dst not an oop");
 300   // Do copy
 301   s->klass()->copy_array(s, src_pos, d, dst_pos, length, thread);
 302 JVM_END
 303 
 304 
 305 static void set_property(Handle props, const char* key, const char* value, TRAPS) {
 306   JavaValue r(T_OBJECT);
 307   // public synchronized Object put(Object key, Object value);
 308   HandleMark hm(THREAD);
 309   Handle key_str    = java_lang_String::create_from_platform_dependent_str(key, CHECK);
 310   Handle value_str  = java_lang_String::create_from_platform_dependent_str((value != NULL ? value : ""), CHECK);
 311   JavaCalls::call_virtual(&r,
 312                           props,
 313                           vmClasses::Properties_klass(),
 314                           vmSymbols::put_name(),
 315                           vmSymbols::object_object_object_signature(),
 316                           key_str,
 317                           value_str,
 318                           THREAD);
 319 }
 320 
 321 
 322 #define PUTPROP(props, name, value) set_property((props), (name), (value), CHECK_(properties));
 323 
 324 /*
 325  * Return all of the system properties in a Java String array with alternating
 326  * names and values from the jvm SystemProperty.
 327  * Which includes some internal and all commandline -D defined properties.
 328  */
 329 JVM_ENTRY(jobjectArray, JVM_GetProperties(JNIEnv *env))
 330   ResourceMark rm(THREAD);
 331   HandleMark hm(THREAD);
 332   int ndx = 0;
 333   int fixedCount = 2;
 334 
 335   SystemProperty* p = Arguments::system_properties();
 336   int count = Arguments::PropertyList_count(p);
 337 
 338   // Allocate result String array
 339   InstanceKlass* ik = vmClasses::String_klass();
 340   objArrayOop r = oopFactory::new_objArray(ik, (count + fixedCount) * 2, CHECK_NULL);
 341   objArrayHandle result_h(THREAD, r);
 342 
 343   while (p != NULL) {
 344     const char * key = p->key();
 345     if (strcmp(key, "sun.nio.MaxDirectMemorySize") != 0) {
 346         const char * value = p->value();
 347         Handle key_str    = java_lang_String::create_from_platform_dependent_str(key, CHECK_NULL);
 348         Handle value_str  = java_lang_String::create_from_platform_dependent_str((value != NULL ? value : ""), CHECK_NULL);
 349         result_h->obj_at_put(ndx * 2,  key_str());
 350         result_h->obj_at_put(ndx * 2 + 1, value_str());
 351         ndx++;
 352     }
 353     p = p->next();
 354   }
 355 
 356   // Convert the -XX:MaxDirectMemorySize= command line flag
 357   // to the sun.nio.MaxDirectMemorySize property.
 358   // Do this after setting user properties to prevent people
 359   // from setting the value with a -D option, as requested.
 360   // Leave empty if not supplied
 361   if (!FLAG_IS_DEFAULT(MaxDirectMemorySize)) {
 362     char as_chars[256];
 363     jio_snprintf(as_chars, sizeof(as_chars), JULONG_FORMAT, MaxDirectMemorySize);
 364     Handle key_str = java_lang_String::create_from_platform_dependent_str("sun.nio.MaxDirectMemorySize", CHECK_NULL);
 365     Handle value_str  = java_lang_String::create_from_platform_dependent_str(as_chars, CHECK_NULL);
 366     result_h->obj_at_put(ndx * 2,  key_str());
 367     result_h->obj_at_put(ndx * 2 + 1, value_str());
 368     ndx++;
 369   }
 370 
 371   // JVM monitoring and management support
 372   // Add the sun.management.compiler property for the compiler's name
 373   {
 374 #undef CSIZE
 375 #if defined(_LP64) || defined(_WIN64)
 376   #define CSIZE "64-Bit "
 377 #else
 378   #define CSIZE
 379 #endif // 64bit
 380 
 381 #if COMPILER1_AND_COMPILER2
 382     const char* compiler_name = "HotSpot " CSIZE "Tiered Compilers";
 383 #else
 384 #if defined(COMPILER1)
 385     const char* compiler_name = "HotSpot " CSIZE "Client Compiler";
 386 #elif defined(COMPILER2)
 387     const char* compiler_name = "HotSpot " CSIZE "Server Compiler";
 388 #elif INCLUDE_JVMCI
 389     #error "INCLUDE_JVMCI should imply COMPILER1_OR_COMPILER2"
 390 #else
 391     const char* compiler_name = "";
 392 #endif // compilers
 393 #endif // COMPILER1_AND_COMPILER2
 394 
 395     if (*compiler_name != '\0' &&
 396         (Arguments::mode() != Arguments::_int)) {
 397       Handle key_str = java_lang_String::create_from_platform_dependent_str("sun.management.compiler", CHECK_NULL);
 398       Handle value_str  = java_lang_String::create_from_platform_dependent_str(compiler_name, CHECK_NULL);
 399       result_h->obj_at_put(ndx * 2,  key_str());
 400       result_h->obj_at_put(ndx * 2 + 1, value_str());
 401       ndx++;
 402     }
 403   }
 404 
 405   return (jobjectArray) JNIHandles::make_local(THREAD, result_h());
 406 JVM_END
 407 
 408 
 409 /*
 410  * Return the temporary directory that the VM uses for the attach
 411  * and perf data files.
 412  *
 413  * It is important that this directory is well-known and the
 414  * same for all VM instances. It cannot be affected by configuration
 415  * variables such as java.io.tmpdir.
 416  */
 417 JVM_ENTRY(jstring, JVM_GetTemporaryDirectory(JNIEnv *env))
 418   HandleMark hm(THREAD);
 419   const char* temp_dir = os::get_temp_directory();
 420   Handle h = java_lang_String::create_from_platform_dependent_str(temp_dir, CHECK_NULL);
 421   return (jstring) JNIHandles::make_local(THREAD, h());
 422 JVM_END
 423 
 424 
 425 // java.lang.Runtime /////////////////////////////////////////////////////////////////////////
 426 
 427 extern volatile jint vm_created;
 428 
 429 JVM_ENTRY_NO_ENV(void, JVM_BeforeHalt())
 430 #if INCLUDE_CDS
 431   // Link all classes for dynamic CDS dumping before vm exit.
 432   if (DynamicArchive::should_dump_at_vm_exit()) {
 433     DynamicArchive::prepare_for_dump_at_exit();
 434   }
 435 #endif
 436   EventShutdown event;
 437   if (event.should_commit()) {
 438     event.set_reason("Shutdown requested from Java");
 439     event.commit();
 440   }
 441 JVM_END
 442 
 443 
 444 JVM_ENTRY_NO_ENV(void, JVM_Halt(jint code))
 445   before_exit(thread, true);
 446   vm_exit(code);
 447 JVM_END
 448 
 449 
 450 JVM_ENTRY_NO_ENV(void, JVM_GC(void))
 451   if (!DisableExplicitGC) {
 452     EventSystemGC event;
 453     event.set_invokedConcurrent(ExplicitGCInvokesConcurrent);
 454     Universe::heap()->collect(GCCause::_java_lang_system_gc);
 455     event.commit();
 456   }
 457 JVM_END
 458 
 459 
 460 JVM_LEAF(jlong, JVM_MaxObjectInspectionAge(void))
 461   return Universe::heap()->millis_since_last_whole_heap_examined();
 462 JVM_END
 463 
 464 
 465 static inline jlong convert_size_t_to_jlong(size_t val) {
 466   // In the 64-bit vm, a size_t can overflow a jlong (which is signed).
 467   NOT_LP64 (return (jlong)val;)
 468   LP64_ONLY(return (jlong)MIN2(val, (size_t)max_jlong);)
 469 }
 470 
 471 JVM_ENTRY_NO_ENV(jlong, JVM_TotalMemory(void))
 472   size_t n = Universe::heap()->capacity();
 473   return convert_size_t_to_jlong(n);
 474 JVM_END
 475 
 476 
 477 JVM_ENTRY_NO_ENV(jlong, JVM_FreeMemory(void))
 478   size_t n = Universe::heap()->unused();
 479   return convert_size_t_to_jlong(n);
 480 JVM_END
 481 
 482 
 483 JVM_ENTRY_NO_ENV(jlong, JVM_MaxMemory(void))
 484   size_t n = Universe::heap()->max_capacity();
 485   return convert_size_t_to_jlong(n);
 486 JVM_END
 487 
 488 
 489 JVM_ENTRY_NO_ENV(jint, JVM_ActiveProcessorCount(void))
 490   return os::active_processor_count();
 491 JVM_END
 492 
 493 JVM_LEAF(jboolean, JVM_IsUseContainerSupport(void))
 494 #ifdef LINUX
 495   if (UseContainerSupport) {
 496     return JNI_TRUE;
 497   }
 498 #endif
 499   return JNI_FALSE;
 500 JVM_END
 501 
 502 // java.lang.Throwable //////////////////////////////////////////////////////
 503 
 504 JVM_ENTRY(void, JVM_FillInStackTrace(JNIEnv *env, jobject receiver))
 505   Handle exception(thread, JNIHandles::resolve_non_null(receiver));
 506   java_lang_Throwable::fill_in_stack_trace(exception);
 507 JVM_END
 508 
 509 // java.lang.NullPointerException ///////////////////////////////////////////
 510 
 511 JVM_ENTRY(jstring, JVM_GetExtendedNPEMessage(JNIEnv *env, jthrowable throwable))
 512   if (!ShowCodeDetailsInExceptionMessages) return NULL;
 513 
 514   oop exc = JNIHandles::resolve_non_null(throwable);
 515 
 516   Method* method;
 517   int bci;
 518   if (!java_lang_Throwable::get_top_method_and_bci(exc, &method, &bci)) {
 519     return NULL;
 520   }
 521   if (method->is_native()) {
 522     return NULL;
 523   }
 524 
 525   stringStream ss;
 526   bool ok = BytecodeUtils::get_NPE_message_at(&ss, method, bci);
 527   if (ok) {
 528     oop result = java_lang_String::create_oop_from_str(ss.base(), CHECK_NULL);
 529     return (jstring) JNIHandles::make_local(THREAD, result);
 530   } else {
 531     return NULL;
 532   }
 533 JVM_END
 534 
 535 // java.lang.StackTraceElement //////////////////////////////////////////////
 536 
 537 
 538 JVM_ENTRY(void, JVM_InitStackTraceElementArray(JNIEnv *env, jobjectArray elements, jobject backtrace, jint depth))
 539   Handle backtraceh(THREAD, JNIHandles::resolve(backtrace));
 540   objArrayOop st = objArrayOop(JNIHandles::resolve(elements));
 541   objArrayHandle stack_trace(THREAD, st);
 542   // Fill in the allocated stack trace
 543   java_lang_Throwable::get_stack_trace_elements(depth, backtraceh, stack_trace, CHECK);
 544 JVM_END
 545 
 546 
 547 JVM_ENTRY(void, JVM_InitStackTraceElement(JNIEnv* env, jobject element, jobject stackFrameInfo))
 548   Handle stack_frame_info(THREAD, JNIHandles::resolve_non_null(stackFrameInfo));
 549   Handle stack_trace_element(THREAD, JNIHandles::resolve_non_null(element));
 550   java_lang_StackFrameInfo::to_stack_trace_element(stack_frame_info, stack_trace_element, THREAD);
 551 JVM_END
 552 
 553 
 554 // java.lang.StackWalker //////////////////////////////////////////////////////
 555 
 556 
 557 JVM_ENTRY(jobject, JVM_CallStackWalk(JNIEnv *env, jobject stackStream, jlong mode,
 558                                      jint skip_frames, jobject contScope, jobject cont,
 559                                      jint frame_count, jint start_index, jobjectArray frames))
 560   if (!thread->has_last_Java_frame()) {
 561     THROW_MSG_(vmSymbols::java_lang_InternalError(), "doStackWalk: no stack trace", NULL);
 562   }
 563 
 564   Handle stackStream_h(THREAD, JNIHandles::resolve_non_null(stackStream));
 565   Handle contScope_h(THREAD, JNIHandles::resolve(contScope));
 566   Handle cont_h(THREAD, JNIHandles::resolve(cont));
 567   // frames array is a Class<?>[] array when only getting caller reference,
 568   // and a StackFrameInfo[] array (or derivative) otherwise. It should never
 569   // be null.
 570   objArrayOop fa = objArrayOop(JNIHandles::resolve_non_null(frames));
 571   objArrayHandle frames_array_h(THREAD, fa);
 572 
 573   int limit = start_index + frame_count;
 574   if (frames_array_h->length() < limit) {
 575     THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(), "not enough space in buffers", NULL);
 576   }
 577 
 578   oop result = StackWalk::walk(stackStream_h, mode, skip_frames, contScope_h, cont_h,
 579                                frame_count, start_index, frames_array_h, CHECK_NULL);
 580   return JNIHandles::make_local(THREAD, result);
 581 JVM_END
 582 
 583 
 584 JVM_ENTRY(jint, JVM_MoreStackWalk(JNIEnv *env, jobject stackStream, jlong mode, jlong anchor,
 585                                   jint frame_count, jint start_index,
 586                                   jobjectArray frames))
 587   // frames array is a Class<?>[] array when only getting caller reference,
 588   // and a StackFrameInfo[] array (or derivative) otherwise. It should never
 589   // be null.
 590   objArrayOop fa = objArrayOop(JNIHandles::resolve_non_null(frames));
 591   objArrayHandle frames_array_h(THREAD, fa);
 592 
 593   int limit = start_index+frame_count;
 594   if (frames_array_h->length() < limit) {
 595     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "not enough space in buffers");
 596   }
 597 
 598   Handle stackStream_h(THREAD, JNIHandles::resolve_non_null(stackStream));
 599   return StackWalk::fetchNextBatch(stackStream_h, mode, anchor, frame_count,
 600                                   start_index, frames_array_h, THREAD);
 601 JVM_END
 602 
 603 JVM_ENTRY(void, JVM_SetStackWalkContinuation(JNIEnv *env, jobject stackStream, jlong anchor, jobjectArray frames, jobject cont))
 604   objArrayOop fa = objArrayOop(JNIHandles::resolve_non_null(frames));
 605   objArrayHandle frames_array_h(THREAD, fa);
 606   Handle stackStream_h(THREAD, JNIHandles::resolve_non_null(stackStream));
 607   Handle cont_h(THREAD, JNIHandles::resolve_non_null(cont));
 608 
 609   StackWalk::setContinuation(stackStream_h, anchor, frames_array_h, cont_h, THREAD);
 610 JVM_END
 611 
 612 // java.lang.Object ///////////////////////////////////////////////
 613 
 614 
 615 JVM_ENTRY(jint, JVM_IHashCode(JNIEnv* env, jobject handle))
 616   // as implemented in the classic virtual machine; return 0 if object is NULL
 617   if (handle == NULL) {
 618     return 0;
 619   }
 620   oop obj = JNIHandles::resolve_non_null(handle);
 621   if (EnableValhalla && obj->klass()->is_inline_klass()) {
 622       JavaValue result(T_INT);
 623       JavaCallArguments args;
 624       Handle ho(THREAD, obj);
 625       args.push_oop(ho);
 626       methodHandle method(THREAD, Universe::value_object_hash_code_method());
 627       JavaCalls::call(&result, method, &args, THREAD);
 628       if (HAS_PENDING_EXCEPTION) {
 629         if (!PENDING_EXCEPTION->is_a(vmClasses::Error_klass())) {
 630           Handle e(THREAD, PENDING_EXCEPTION);
 631           CLEAR_PENDING_EXCEPTION;
 632           THROW_MSG_CAUSE_(vmSymbols::java_lang_InternalError(), "Internal error in hashCode", e, false);
 633         }
 634       }
 635       return result.get_jint();
 636   } else {
 637     return ObjectSynchronizer::FastHashCode(THREAD, obj);
 638   }
 639 JVM_END
 640 
 641 
 642 JVM_ENTRY(void, JVM_MonitorWait(JNIEnv* env, jobject handle, jlong ms))
 643   Handle obj(THREAD, JNIHandles::resolve_non_null(handle));
 644   JavaThreadInObjectWaitState jtiows(thread, ms != 0);
 645   if (JvmtiExport::should_post_monitor_wait()) {
 646     JvmtiExport::post_monitor_wait(thread, obj(), ms);
 647 
 648     // The current thread already owns the monitor and it has not yet
 649     // been added to the wait queue so the current thread cannot be
 650     // made the successor. This means that the JVMTI_EVENT_MONITOR_WAIT
 651     // event handler cannot accidentally consume an unpark() meant for
 652     // the ParkEvent associated with this ObjectMonitor.
 653   }
 654   ObjectSynchronizer::wait(obj, ms, CHECK);
 655 JVM_END
 656 
 657 
 658 JVM_ENTRY(void, JVM_MonitorNotify(JNIEnv* env, jobject handle))
 659   Handle obj(THREAD, JNIHandles::resolve_non_null(handle));
 660   ObjectSynchronizer::notify(obj, CHECK);
 661 JVM_END
 662 
 663 
 664 JVM_ENTRY(void, JVM_MonitorNotifyAll(JNIEnv* env, jobject handle))
 665   Handle obj(THREAD, JNIHandles::resolve_non_null(handle));
 666   ObjectSynchronizer::notifyall(obj, CHECK);
 667 JVM_END
 668 
 669 
 670 JVM_ENTRY(jobject, JVM_Clone(JNIEnv* env, jobject handle))
 671   Handle obj(THREAD, JNIHandles::resolve_non_null(handle));
 672   Klass* klass = obj->klass();
 673   JvmtiVMObjectAllocEventCollector oam;
 674 
 675 #ifdef ASSERT
 676   // Just checking that the cloneable flag is set correct
 677   if (obj->is_array()) {
 678     guarantee(klass->is_cloneable(), "all arrays are cloneable");
 679   } else {
 680     guarantee(obj->is_instance(), "should be instanceOop");
 681     bool cloneable = klass->is_subtype_of(vmClasses::Cloneable_klass());
 682     guarantee(cloneable == klass->is_cloneable(), "incorrect cloneable flag");
 683   }
 684 #endif
 685 
 686   // Check if class of obj supports the Cloneable interface.
 687   // All arrays are considered to be cloneable (See JLS 20.1.5).
 688   // All j.l.r.Reference classes are considered non-cloneable.
 689   if (!klass->is_cloneable() ||
 690        klass->is_inline_klass() ||
 691       (klass->is_instance_klass() &&
 692        InstanceKlass::cast(klass)->reference_type() != REF_NONE)) {
 693     ResourceMark rm(THREAD);
 694     THROW_MSG_0(vmSymbols::java_lang_CloneNotSupportedException(), klass->external_name());
 695   }
 696 
 697   // Make shallow object copy
 698   const size_t size = obj->size();
 699   oop new_obj_oop = NULL;
 700   if (obj->is_array()) {
 701     const int length = ((arrayOop)obj())->length();
 702     new_obj_oop = Universe::heap()->array_allocate(klass, size, length,
 703                                                    /* do_zero */ true, CHECK_NULL);
 704   } else {
 705     new_obj_oop = Universe::heap()->obj_allocate(klass, size, CHECK_NULL);
 706   }
 707 
 708   HeapAccess<>::clone(obj(), new_obj_oop, size);
 709 
 710   Handle new_obj(THREAD, new_obj_oop);
 711   // Caution: this involves a java upcall, so the clone should be
 712   // "gc-robust" by this stage.
 713   if (klass->has_finalizer()) {
 714     assert(obj->is_instance(), "should be instanceOop");
 715     new_obj_oop = InstanceKlass::register_finalizer(instanceOop(new_obj()), CHECK_NULL);
 716     new_obj = Handle(THREAD, new_obj_oop);
 717   }
 718 
 719   return JNIHandles::make_local(THREAD, new_obj());
 720 JVM_END
 721 
 722 // java.lang.ref.Finalizer ////////////////////////////////////////////////////
 723 
 724 JVM_ENTRY(void, JVM_ReportFinalizationComplete(JNIEnv * env, jobject finalizee))
 725   MANAGEMENT_ONLY(FinalizerService::on_complete(JNIHandles::resolve_non_null(finalizee), THREAD);)
 726 JVM_END
 727 
 728 JVM_LEAF(jboolean, JVM_IsFinalizationEnabled(JNIEnv * env))
 729   return InstanceKlass::is_finalization_enabled();
 730 JVM_END
 731 
 732 // jdk.internal.vm.Continuation /////////////////////////////////////////////////////
 733 
 734 JVM_ENTRY(void, JVM_RegisterContinuationMethods(JNIEnv *env, jclass cls))
 735   CONT_RegisterNativeMethods(env, cls);
 736 JVM_END
 737 
 738 // java.io.File ///////////////////////////////////////////////////////////////
 739 
 740 JVM_LEAF(char*, JVM_NativePath(char* path))
 741   return os::native_path(path);
 742 JVM_END
 743 
 744 
 745 // Misc. class handling ///////////////////////////////////////////////////////////
 746 
 747 
 748 JVM_ENTRY(jclass, JVM_GetCallerClass(JNIEnv* env))
 749   // Getting the class of the caller frame.
 750   //
 751   // The call stack at this point looks something like this:
 752   //
 753   // [0] [ @CallerSensitive public sun.reflect.Reflection.getCallerClass ]
 754   // [1] [ @CallerSensitive API.method                                   ]
 755   // [.] [ (skipped intermediate frames)                                 ]
 756   // [n] [ caller                                                        ]
 757   vframeStream vfst(thread);
 758   // Cf. LibraryCallKit::inline_native_Reflection_getCallerClass
 759   for (int n = 0; !vfst.at_end(); vfst.security_next(), n++) {
 760     Method* m = vfst.method();
 761     assert(m != NULL, "sanity");
 762     switch (n) {
 763     case 0:
 764       // This must only be called from Reflection.getCallerClass
 765       if (m->intrinsic_id() != vmIntrinsics::_getCallerClass) {
 766         THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "JVM_GetCallerClass must only be called from Reflection.getCallerClass");
 767       }
 768       // fall-through
 769     case 1:
 770       // Frame 0 and 1 must be caller sensitive.
 771       if (!m->caller_sensitive()) {
 772         THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), err_msg("CallerSensitive annotation expected at frame %d", n));
 773       }
 774       break;
 775     default:
 776       if (!m->is_ignored_by_security_stack_walk()) {
 777         // We have reached the desired frame; return the holder class.
 778         return (jclass) JNIHandles::make_local(THREAD, m->method_holder()->java_mirror());
 779       }
 780       break;
 781     }
 782   }
 783   return NULL;
 784 JVM_END
 785 
 786 
 787 JVM_ENTRY(jclass, JVM_FindPrimitiveClass(JNIEnv* env, const char* utf))
 788   oop mirror = NULL;
 789   BasicType t = name2type(utf);
 790   if (t != T_ILLEGAL && !is_reference_type(t)) {
 791     mirror = Universe::java_mirror(t);
 792   }
 793   if (mirror == NULL) {
 794     THROW_MSG_0(vmSymbols::java_lang_ClassNotFoundException(), (char*) utf);
 795   } else {
 796     return (jclass) JNIHandles::make_local(THREAD, mirror);
 797   }
 798 JVM_END
 799 
 800 
 801 // Returns a class loaded by the bootstrap class loader; or null
 802 // if not found.  ClassNotFoundException is not thrown.
 803 // FindClassFromBootLoader is exported to the launcher for windows.
 804 JVM_ENTRY(jclass, JVM_FindClassFromBootLoader(JNIEnv* env,
 805                                               const char* name))
 806   // Java libraries should ensure that name is never null or illegal.
 807   if (name == NULL || (int)strlen(name) > Symbol::max_length()) {
 808     // It's impossible to create this class;  the name cannot fit
 809     // into the constant pool.
 810     return NULL;
 811   }
 812   assert(UTF8::is_legal_utf8((const unsigned char*)name, (int)strlen(name), false), "illegal UTF name");
 813 
 814   TempNewSymbol h_name = SymbolTable::new_symbol(name);
 815   Klass* k = SystemDictionary::resolve_or_null(h_name, CHECK_NULL);
 816   if (k == NULL) {
 817     return NULL;
 818   }
 819 
 820   if (log_is_enabled(Debug, class, resolve)) {
 821     trace_class_resolution(k);
 822   }
 823   return (jclass) JNIHandles::make_local(THREAD, k->java_mirror());
 824 JVM_END
 825 
 826 // Find a class with this name in this loader, using the caller's protection domain.
 827 JVM_ENTRY(jclass, JVM_FindClassFromCaller(JNIEnv* env, const char* name,
 828                                           jboolean init, jobject loader,
 829                                           jclass caller))
 830   TempNewSymbol h_name =
 831        SystemDictionary::class_name_symbol(name, vmSymbols::java_lang_ClassNotFoundException(),
 832                                            CHECK_NULL);
 833 
 834   oop loader_oop = JNIHandles::resolve(loader);
 835   oop from_class = JNIHandles::resolve(caller);
 836   oop protection_domain = NULL;
 837   // If loader is null, shouldn't call ClassLoader.checkPackageAccess; otherwise get
 838   // NPE. Put it in another way, the bootstrap class loader has all permission and
 839   // thus no checkPackageAccess equivalence in the VM class loader.
 840   // The caller is also passed as NULL by the java code if there is no security
 841   // manager to avoid the performance cost of getting the calling class.
 842   if (from_class != NULL && loader_oop != NULL) {
 843     protection_domain = java_lang_Class::as_Klass(from_class)->protection_domain();
 844   }
 845 
 846   Handle h_loader(THREAD, loader_oop);
 847   Handle h_prot(THREAD, protection_domain);
 848   jclass result = find_class_from_class_loader(env, h_name, init, h_loader,
 849                                                h_prot, false, THREAD);
 850 
 851   if (log_is_enabled(Debug, class, resolve) && result != NULL) {
 852     trace_class_resolution(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(result)));
 853   }
 854   return result;
 855 JVM_END
 856 
 857 // Currently only called from the old verifier.
 858 JVM_ENTRY(jclass, JVM_FindClassFromClass(JNIEnv *env, const char *name,
 859                                          jboolean init, jclass from))
 860   TempNewSymbol h_name =
 861        SystemDictionary::class_name_symbol(name, vmSymbols::java_lang_ClassNotFoundException(),
 862                                            CHECK_NULL);
 863   oop from_class_oop = JNIHandles::resolve(from);
 864   Klass* from_class = (from_class_oop == NULL)
 865                            ? (Klass*)NULL
 866                            : java_lang_Class::as_Klass(from_class_oop);
 867   oop class_loader = NULL;
 868   oop protection_domain = NULL;
 869   if (from_class != NULL) {
 870     class_loader = from_class->class_loader();
 871     protection_domain = from_class->protection_domain();
 872   }
 873   Handle h_loader(THREAD, class_loader);
 874   Handle h_prot  (THREAD, protection_domain);
 875   jclass result = find_class_from_class_loader(env, h_name, init, h_loader,
 876                                                h_prot, true, thread);
 877 
 878   if (log_is_enabled(Debug, class, resolve) && result != NULL) {
 879     // this function is generally only used for class loading during verification.
 880     ResourceMark rm;
 881     oop from_mirror = JNIHandles::resolve_non_null(from);
 882     Klass* from_class = java_lang_Class::as_Klass(from_mirror);
 883     const char * from_name = from_class->external_name();
 884 
 885     oop mirror = JNIHandles::resolve_non_null(result);
 886     Klass* to_class = java_lang_Class::as_Klass(mirror);
 887     const char * to = to_class->external_name();
 888     log_debug(class, resolve)("%s %s (verification)", from_name, to);
 889   }
 890 
 891   return result;
 892 JVM_END
 893 
 894 // common code for JVM_DefineClass() and JVM_DefineClassWithSource()
 895 static jclass jvm_define_class_common(const char *name,
 896                                       jobject loader, const jbyte *buf,
 897                                       jsize len, jobject pd, const char *source,
 898                                       TRAPS) {
 899   if (source == NULL)  source = "__JVM_DefineClass__";
 900 
 901   JavaThread* jt = THREAD;
 902 
 903   PerfClassTraceTime vmtimer(ClassLoader::perf_define_appclass_time(),
 904                              ClassLoader::perf_define_appclass_selftime(),
 905                              ClassLoader::perf_define_appclasses(),
 906                              jt->get_thread_stat()->perf_recursion_counts_addr(),
 907                              jt->get_thread_stat()->perf_timers_addr(),
 908                              PerfClassTraceTime::DEFINE_CLASS);
 909 
 910   if (UsePerfData) {
 911     ClassLoader::perf_app_classfile_bytes_read()->inc(len);
 912   }
 913 
 914   // Class resolution will get the class name from the .class stream if the name is null.
 915   TempNewSymbol class_name = name == NULL ? NULL :
 916        SystemDictionary::class_name_symbol(name, vmSymbols::java_lang_NoClassDefFoundError(),
 917                                            CHECK_NULL);
 918 
 919   ResourceMark rm(THREAD);
 920   ClassFileStream st((u1*)buf, len, source, ClassFileStream::verify);
 921   Handle class_loader (THREAD, JNIHandles::resolve(loader));
 922   Handle protection_domain (THREAD, JNIHandles::resolve(pd));
 923   ClassLoadInfo cl_info(protection_domain);
 924   Klass* k = SystemDictionary::resolve_from_stream(&st, class_name,
 925                                                    class_loader,
 926                                                    cl_info,
 927                                                    CHECK_NULL);
 928 
 929   if (log_is_enabled(Debug, class, resolve)) {
 930     trace_class_resolution(k);
 931   }
 932 
 933   return (jclass) JNIHandles::make_local(THREAD, k->java_mirror());
 934 }
 935 
 936 enum {
 937   NESTMATE              = java_lang_invoke_MemberName::MN_NESTMATE_CLASS,
 938   HIDDEN_CLASS          = java_lang_invoke_MemberName::MN_HIDDEN_CLASS,
 939   STRONG_LOADER_LINK    = java_lang_invoke_MemberName::MN_STRONG_LOADER_LINK,
 940   ACCESS_VM_ANNOTATIONS = java_lang_invoke_MemberName::MN_ACCESS_VM_ANNOTATIONS
 941 };
 942 
 943 /*
 944  * Define a class with the specified flags that indicates if it's a nestmate,
 945  * hidden, or strongly referenced from class loader.
 946  */
 947 static jclass jvm_lookup_define_class(jclass lookup, const char *name,
 948                                       const jbyte *buf, jsize len, jobject pd,
 949                                       jboolean init, int flags, jobject classData, TRAPS) {
 950   ResourceMark rm(THREAD);
 951 
 952   Klass* lookup_k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(lookup));
 953   // Lookup class must be a non-null instance
 954   if (lookup_k == NULL) {
 955     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Lookup class is null");
 956   }
 957   assert(lookup_k->is_instance_klass(), "Lookup class must be an instance klass");
 958 
 959   Handle class_loader (THREAD, lookup_k->class_loader());
 960 
 961   bool is_nestmate = (flags & NESTMATE) == NESTMATE;
 962   bool is_hidden = (flags & HIDDEN_CLASS) == HIDDEN_CLASS;
 963   bool is_strong = (flags & STRONG_LOADER_LINK) == STRONG_LOADER_LINK;
 964   bool vm_annotations = (flags & ACCESS_VM_ANNOTATIONS) == ACCESS_VM_ANNOTATIONS;
 965 
 966   InstanceKlass* host_class = NULL;
 967   if (is_nestmate) {
 968     host_class = InstanceKlass::cast(lookup_k)->nest_host(CHECK_NULL);
 969   }
 970 
 971   log_info(class, nestmates)("LookupDefineClass: %s - %s%s, %s, %s, %s",
 972                              name,
 973                              is_nestmate ? "with dynamic nest-host " : "non-nestmate",
 974                              is_nestmate ? host_class->external_name() : "",
 975                              is_hidden ? "hidden" : "not hidden",
 976                              is_strong ? "strong" : "weak",
 977                              vm_annotations ? "with vm annotations" : "without vm annotation");
 978 
 979   if (!is_hidden) {
 980     // classData is only applicable for hidden classes
 981     if (classData != NULL) {
 982       THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "classData is only applicable for hidden classes");
 983     }
 984     if (is_nestmate) {
 985       THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "dynamic nestmate is only applicable for hidden classes");
 986     }
 987     if (!is_strong) {
 988       THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "an ordinary class must be strongly referenced by its defining loader");
 989     }
 990     if (vm_annotations) {
 991       THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "vm annotations only allowed for hidden classes");
 992     }
 993     if (flags != STRONG_LOADER_LINK) {
 994       THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(),
 995                   err_msg("invalid flag 0x%x", flags));
 996     }
 997   }
 998 
 999   // Class resolution will get the class name from the .class stream if the name is null.
1000   TempNewSymbol class_name = name == NULL ? NULL :
1001        SystemDictionary::class_name_symbol(name, vmSymbols::java_lang_NoClassDefFoundError(),
1002                                            CHECK_NULL);
1003 
1004   Handle protection_domain (THREAD, JNIHandles::resolve(pd));
1005   const char* source = is_nestmate ? host_class->external_name() : "__JVM_LookupDefineClass__";
1006   ClassFileStream st((u1*)buf, len, source, ClassFileStream::verify);
1007 
1008   InstanceKlass* ik = NULL;
1009   if (!is_hidden) {
1010     ClassLoadInfo cl_info(protection_domain);
1011     ik = SystemDictionary::resolve_from_stream(&st, class_name,
1012                                                class_loader,
1013                                                cl_info,
1014                                                CHECK_NULL);
1015 
1016     if (log_is_enabled(Debug, class, resolve)) {
1017       trace_class_resolution(ik);
1018     }
1019   } else { // hidden
1020     Handle classData_h(THREAD, JNIHandles::resolve(classData));
1021     ClassLoadInfo cl_info(protection_domain,
1022                           host_class,
1023                           classData_h,
1024                           is_hidden,
1025                           is_strong,
1026                           vm_annotations);
1027     ik = SystemDictionary::resolve_from_stream(&st, class_name,
1028                                                class_loader,
1029                                                cl_info,
1030                                                CHECK_NULL);
1031 
1032     // The hidden class loader data has been artificially been kept alive to
1033     // this point. The mirror and any instances of this class have to keep
1034     // it alive afterwards.
1035     ik->class_loader_data()->dec_keep_alive();
1036 
1037     if (is_nestmate && log_is_enabled(Debug, class, nestmates)) {
1038       ModuleEntry* module = ik->module();
1039       const char * module_name = module->is_named() ? module->name()->as_C_string() : UNNAMED_MODULE;
1040       log_debug(class, nestmates)("Dynamic nestmate: %s/%s, nest_host %s, %s",
1041                                   module_name,
1042                                   ik->external_name(),
1043                                   host_class->external_name(),
1044                                   ik->is_hidden() ? "is hidden" : "is not hidden");
1045     }
1046   }
1047   assert(Reflection::is_same_class_package(lookup_k, ik),
1048          "lookup class and defined class are in different packages");
1049 
1050   if (init) {
1051     ik->initialize(CHECK_NULL);
1052   } else {
1053     ik->link_class(CHECK_NULL);
1054   }
1055 
1056   return (jclass) JNIHandles::make_local(THREAD, ik->java_mirror());
1057 }
1058 
1059 JVM_ENTRY(jclass, JVM_DefineClass(JNIEnv *env, const char *name, jobject loader, const jbyte *buf, jsize len, jobject pd))
1060   return jvm_define_class_common(name, loader, buf, len, pd, NULL, THREAD);
1061 JVM_END
1062 
1063 /*
1064  * Define a class with the specified lookup class.
1065  *  lookup:  Lookup class
1066  *  name:    the name of the class
1067  *  buf:     class bytes
1068  *  len:     length of class bytes
1069  *  pd:      protection domain
1070  *  init:    initialize the class
1071  *  flags:   properties of the class
1072  *  classData: private static pre-initialized field
1073  */
1074 JVM_ENTRY(jclass, JVM_LookupDefineClass(JNIEnv *env, jclass lookup, const char *name, const jbyte *buf,
1075           jsize len, jobject pd, jboolean initialize, int flags, jobject classData))
1076 
1077   if (lookup == NULL) {
1078     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Lookup class is null");
1079   }
1080 
1081   assert(buf != NULL, "buf must not be NULL");
1082 
1083   return jvm_lookup_define_class(lookup, name, buf, len, pd, initialize, flags, classData, THREAD);
1084 JVM_END
1085 
1086 JVM_ENTRY(jclass, JVM_DefineClassWithSource(JNIEnv *env, const char *name, jobject loader, const jbyte *buf, jsize len, jobject pd, const char *source))
1087 
1088   return jvm_define_class_common(name, loader, buf, len, pd, source, THREAD);
1089 JVM_END
1090 
1091 JVM_ENTRY(jclass, JVM_FindLoadedClass(JNIEnv *env, jobject loader, jstring name))
1092   ResourceMark rm(THREAD);
1093 
1094   Handle h_name (THREAD, JNIHandles::resolve_non_null(name));
1095   char* str = java_lang_String::as_utf8_string(h_name());
1096 
1097   // Sanity check, don't expect null
1098   if (str == NULL) return NULL;
1099 
1100   // Internalize the string, converting '.' to '/' in string.
1101   char* p = (char*)str;
1102   while (*p != '\0') {
1103     if (*p == '.') {
1104       *p = '/';
1105     }
1106     p++;
1107   }
1108 
1109   const int str_len = (int)(p - str);
1110   if (str_len > Symbol::max_length()) {
1111     // It's impossible to create this class;  the name cannot fit
1112     // into the constant pool.
1113     return NULL;
1114   }
1115   TempNewSymbol klass_name = SymbolTable::new_symbol(str, str_len);
1116 
1117   // Security Note:
1118   //   The Java level wrapper will perform the necessary security check allowing
1119   //   us to pass the NULL as the initiating class loader.
1120   Handle h_loader(THREAD, JNIHandles::resolve(loader));
1121   Klass* k = SystemDictionary::find_instance_or_array_klass(THREAD, klass_name,
1122                                                             h_loader,
1123                                                             Handle());
1124 #if INCLUDE_CDS
1125   if (k == NULL) {
1126     // If the class is not already loaded, try to see if it's in the shared
1127     // archive for the current classloader (h_loader).
1128     k = SystemDictionaryShared::find_or_load_shared_class(klass_name, h_loader, CHECK_NULL);
1129   }
1130 #endif
1131   return (k == NULL) ? NULL :
1132             (jclass) JNIHandles::make_local(THREAD, k->java_mirror());
1133 JVM_END
1134 
1135 // Module support //////////////////////////////////////////////////////////////////////////////
1136 
1137 JVM_ENTRY(void, JVM_DefineModule(JNIEnv *env, jobject module, jboolean is_open, jstring version,
1138                                  jstring location, jobjectArray packages))
1139   Handle h_module (THREAD, JNIHandles::resolve(module));
1140   Modules::define_module(h_module, is_open, version, location, packages, CHECK);
1141 JVM_END
1142 
1143 JVM_ENTRY(void, JVM_SetBootLoaderUnnamedModule(JNIEnv *env, jobject module))
1144   Handle h_module (THREAD, JNIHandles::resolve(module));
1145   Modules::set_bootloader_unnamed_module(h_module, CHECK);
1146 JVM_END
1147 
1148 JVM_ENTRY(void, JVM_AddModuleExports(JNIEnv *env, jobject from_module, jstring package, jobject to_module))
1149   Handle h_from_module (THREAD, JNIHandles::resolve(from_module));
1150   Handle h_to_module (THREAD, JNIHandles::resolve(to_module));
1151   Modules::add_module_exports_qualified(h_from_module, package, h_to_module, CHECK);
1152 JVM_END
1153 
1154 JVM_ENTRY(void, JVM_AddModuleExportsToAllUnnamed(JNIEnv *env, jobject from_module, jstring package))
1155   Handle h_from_module (THREAD, JNIHandles::resolve(from_module));
1156   Modules::add_module_exports_to_all_unnamed(h_from_module, package, CHECK);
1157 JVM_END
1158 
1159 JVM_ENTRY(void, JVM_AddModuleExportsToAll(JNIEnv *env, jobject from_module, jstring package))
1160   Handle h_from_module (THREAD, JNIHandles::resolve(from_module));
1161   Modules::add_module_exports(h_from_module, package, Handle(), CHECK);
1162 JVM_END
1163 
1164 JVM_ENTRY (void, JVM_AddReadsModule(JNIEnv *env, jobject from_module, jobject source_module))
1165   Handle h_from_module (THREAD, JNIHandles::resolve(from_module));
1166   Handle h_source_module (THREAD, JNIHandles::resolve(source_module));
1167   Modules::add_reads_module(h_from_module, h_source_module, CHECK);
1168 JVM_END
1169 
1170 JVM_ENTRY(void, JVM_DefineArchivedModules(JNIEnv *env, jobject platform_loader, jobject system_loader))
1171   Handle h_platform_loader (THREAD, JNIHandles::resolve(platform_loader));
1172   Handle h_system_loader (THREAD, JNIHandles::resolve(system_loader));
1173   Modules::define_archived_modules(h_platform_loader, h_system_loader, CHECK);
1174 JVM_END
1175 
1176 // Reflection support //////////////////////////////////////////////////////////////////////////////
1177 
1178 JVM_ENTRY(jstring, JVM_InitClassName(JNIEnv *env, jclass cls))
1179   assert (cls != NULL, "illegal class");
1180   JvmtiVMObjectAllocEventCollector oam;
1181   ResourceMark rm(THREAD);
1182   HandleMark hm(THREAD);
1183   Handle java_class(THREAD, JNIHandles::resolve(cls));
1184   oop result = java_lang_Class::name(java_class, CHECK_NULL);
1185   return (jstring) JNIHandles::make_local(THREAD, result);
1186 JVM_END
1187 
1188 
1189 JVM_ENTRY(jobjectArray, JVM_GetClassInterfaces(JNIEnv *env, jclass cls))
1190   JvmtiVMObjectAllocEventCollector oam;
1191   oop mirror = JNIHandles::resolve_non_null(cls);
1192 
1193   // Special handling for primitive objects
1194   if (java_lang_Class::is_primitive(mirror)) {
1195     // Primitive objects does not have any interfaces
1196     objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(), 0, CHECK_NULL);
1197     return (jobjectArray) JNIHandles::make_local(THREAD, r);
1198   }
1199 
1200   Klass* klass = java_lang_Class::as_Klass(mirror);
1201   // Figure size of result array
1202   int size;
1203   if (klass->is_instance_klass()) {
1204     InstanceKlass* ik = InstanceKlass::cast(klass);
1205     size = ik->local_interfaces()->length();
1206   } else {
1207     assert(klass->is_objArray_klass() || klass->is_typeArray_klass() || klass->is_flatArray_klass(), "Illegal mirror klass");
1208     size = 2;
1209   }
1210 
1211   // Allocate result array
1212   objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(), size, CHECK_NULL);
1213   objArrayHandle result (THREAD, r);
1214   // Fill in result
1215   if (klass->is_instance_klass()) {
1216     // Regular instance klass, fill in all local interfaces
1217     for (int index = 0; index < size; index++) {
1218       InstanceKlass* ik = InstanceKlass::cast(klass);
1219       Klass* k = ik->local_interfaces()->at(index);
1220       result->obj_at_put(index, k->java_mirror());
1221     }
1222   } else {
1223     // All arrays implement java.lang.Cloneable and java.io.Serializable
1224     result->obj_at_put(0, vmClasses::Cloneable_klass()->java_mirror());
1225     result->obj_at_put(1, vmClasses::Serializable_klass()->java_mirror());
1226   }
1227   return (jobjectArray) JNIHandles::make_local(THREAD, result());
1228 JVM_END
1229 
1230 
1231 JVM_ENTRY(jboolean, JVM_IsInterface(JNIEnv *env, jclass cls))
1232   oop mirror = JNIHandles::resolve_non_null(cls);
1233   if (java_lang_Class::is_primitive(mirror)) {
1234     return JNI_FALSE;
1235   }
1236   Klass* k = java_lang_Class::as_Klass(mirror);
1237   jboolean result = k->is_interface();
1238   assert(!result || k->is_instance_klass(),
1239          "all interfaces are instance types");
1240   // The compiler intrinsic for isInterface tests the
1241   // Klass::_access_flags bits in the same way.
1242   return result;
1243 JVM_END
1244 
1245 JVM_ENTRY(jboolean, JVM_IsHiddenClass(JNIEnv *env, jclass cls))
1246   oop mirror = JNIHandles::resolve_non_null(cls);
1247   if (java_lang_Class::is_primitive(mirror)) {
1248     return JNI_FALSE;
1249   }
1250   Klass* k = java_lang_Class::as_Klass(mirror);
1251   return k->is_hidden();
1252 JVM_END
1253 
1254 JVM_ENTRY(jboolean, JVM_IsIdentityClass(JNIEnv *env, jclass cls))
1255   oop mirror = JNIHandles::resolve_non_null(cls);
1256   if (java_lang_Class::is_primitive(mirror)) {
1257     return JNI_FALSE;
1258   }
1259   Klass* k = java_lang_Class::as_Klass(mirror);
1260   if (EnableValhalla) {
1261     return k->is_array_klass() || k->is_identity_class();
1262   } else {
1263     return k->is_interface() ? JNI_FALSE : JNI_TRUE;
1264   }
1265 JVM_END
1266 
1267 JVM_ENTRY(jobjectArray, JVM_GetClassSigners(JNIEnv *env, jclass cls))
1268   JvmtiVMObjectAllocEventCollector oam;
1269   oop mirror = JNIHandles::resolve_non_null(cls);
1270   if (java_lang_Class::is_primitive(mirror)) {
1271     // There are no signers for primitive types
1272     return NULL;
1273   }
1274 
1275   objArrayHandle signers(THREAD, java_lang_Class::signers(mirror));
1276 
1277   // If there are no signers set in the class, or if the class
1278   // is an array, return NULL.
1279   if (signers == NULL) return NULL;
1280 
1281   // copy of the signers array
1282   Klass* element = ObjArrayKlass::cast(signers->klass())->element_klass();
1283   objArrayOop signers_copy = oopFactory::new_objArray(element, signers->length(), CHECK_NULL);
1284   for (int index = 0; index < signers->length(); index++) {
1285     signers_copy->obj_at_put(index, signers->obj_at(index));
1286   }
1287 
1288   // return the copy
1289   return (jobjectArray) JNIHandles::make_local(THREAD, signers_copy);
1290 JVM_END
1291 
1292 
1293 JVM_ENTRY(void, JVM_SetClassSigners(JNIEnv *env, jclass cls, jobjectArray signers))
1294   oop mirror = JNIHandles::resolve_non_null(cls);
1295   if (!java_lang_Class::is_primitive(mirror)) {
1296     // This call is ignored for primitive types and arrays.
1297     // Signers are only set once, ClassLoader.java, and thus shouldn't
1298     // be called with an array.  Only the bootstrap loader creates arrays.
1299     Klass* k = java_lang_Class::as_Klass(mirror);
1300     if (k->is_instance_klass()) {
1301       java_lang_Class::set_signers(k->java_mirror(), objArrayOop(JNIHandles::resolve(signers)));
1302     }
1303   }
1304 JVM_END
1305 
1306 
1307 JVM_ENTRY(jobject, JVM_GetProtectionDomain(JNIEnv *env, jclass cls))
1308   oop mirror = JNIHandles::resolve_non_null(cls);
1309   if (mirror == NULL) {
1310     THROW_(vmSymbols::java_lang_NullPointerException(), NULL);
1311   }
1312 
1313   if (java_lang_Class::is_primitive(mirror)) {
1314     // Primitive types does not have a protection domain.
1315     return NULL;
1316   }
1317 
1318   oop pd = java_lang_Class::protection_domain(mirror);
1319   return (jobject) JNIHandles::make_local(THREAD, pd);
1320 JVM_END
1321 
1322 
1323 // Returns the inherited_access_control_context field of the running thread.
1324 JVM_ENTRY(jobject, JVM_GetInheritedAccessControlContext(JNIEnv *env, jclass cls))
1325   oop result = java_lang_Thread::inherited_access_control_context(thread->threadObj());
1326   return JNIHandles::make_local(THREAD, result);
1327 JVM_END
1328 
1329 JVM_ENTRY(jobject, JVM_GetStackAccessControlContext(JNIEnv *env, jclass cls))
1330   if (!UsePrivilegedStack) return NULL;
1331 
1332   ResourceMark rm(THREAD);
1333   GrowableArray<Handle>* local_array = new GrowableArray<Handle>(12);
1334   JvmtiVMObjectAllocEventCollector oam;
1335 
1336   // count the protection domains on the execution stack. We collapse
1337   // duplicate consecutive protection domains into a single one, as
1338   // well as stopping when we hit a privileged frame.
1339 
1340   oop previous_protection_domain = NULL;
1341   Handle privileged_context(thread, NULL);
1342   bool is_privileged = false;
1343   oop protection_domain = NULL;
1344 
1345   // Iterate through Java frames
1346   vframeStream vfst(thread);
1347   for(; !vfst.at_end(); vfst.next()) {
1348     // get method of frame
1349     Method* method = vfst.method();
1350 
1351     // stop at the first privileged frame
1352     if (method->method_holder() == vmClasses::AccessController_klass() &&
1353       method->name() == vmSymbols::executePrivileged_name())
1354     {
1355       // this frame is privileged
1356       is_privileged = true;
1357 
1358       javaVFrame *priv = vfst.asJavaVFrame();       // executePrivileged
1359 
1360       StackValueCollection* locals = priv->locals();
1361       StackValue* ctx_sv = locals->at(1); // AccessControlContext context
1362       StackValue* clr_sv = locals->at(2); // Class<?> caller
1363       assert(!ctx_sv->obj_is_scalar_replaced(), "found scalar-replaced object");
1364       assert(!clr_sv->obj_is_scalar_replaced(), "found scalar-replaced object");
1365       privileged_context    = ctx_sv->get_obj();
1366       Handle caller         = clr_sv->get_obj();
1367 
1368       Klass *caller_klass = java_lang_Class::as_Klass(caller());
1369       protection_domain  = caller_klass->protection_domain();
1370     } else {
1371       protection_domain = method->method_holder()->protection_domain();
1372     }
1373 
1374     if ((previous_protection_domain != protection_domain) && (protection_domain != NULL)) {
1375       local_array->push(Handle(thread, protection_domain));
1376       previous_protection_domain = protection_domain;
1377     }
1378 
1379     if (is_privileged) break;
1380   }
1381 
1382 
1383   // either all the domains on the stack were system domains, or
1384   // we had a privileged system domain
1385   if (local_array->is_empty()) {
1386     if (is_privileged && privileged_context.is_null()) return NULL;
1387 
1388     oop result = java_security_AccessControlContext::create(objArrayHandle(), is_privileged, privileged_context, CHECK_NULL);
1389     return JNIHandles::make_local(THREAD, result);
1390   }
1391 
1392   objArrayOop context = oopFactory::new_objArray(vmClasses::ProtectionDomain_klass(),
1393                                                  local_array->length(), CHECK_NULL);
1394   objArrayHandle h_context(thread, context);
1395   for (int index = 0; index < local_array->length(); index++) {
1396     h_context->obj_at_put(index, local_array->at(index)());
1397   }
1398 
1399   oop result = java_security_AccessControlContext::create(h_context, is_privileged, privileged_context, CHECK_NULL);
1400 
1401   return JNIHandles::make_local(THREAD, result);
1402 JVM_END
1403 
1404 class ScopedValueBindingsResolver {
1405 public:
1406   InstanceKlass* Carrier_klass;
1407   ScopedValueBindingsResolver(JavaThread* THREAD) {
1408     Klass *k = SystemDictionary::resolve_or_fail(vmSymbols::jdk_incubator_concurrent_ScopedValue_Carrier(), true, THREAD);
1409     Carrier_klass = InstanceKlass::cast(k);
1410   }
1411 };
1412 
1413 JVM_ENTRY(jobject, JVM_FindScopedValueBindings(JNIEnv *env, jclass cls))
1414   ResourceMark rm(THREAD);
1415   GrowableArray<Handle>* local_array = new GrowableArray<Handle>(12);
1416   JvmtiVMObjectAllocEventCollector oam;
1417 
1418   static ScopedValueBindingsResolver resolver(THREAD);
1419 
1420   // Iterate through Java frames
1421   vframeStream vfst(thread);
1422   for(; !vfst.at_end(); vfst.next()) {
1423     int loc = -1;
1424     // get method of frame
1425     Method* method = vfst.method();
1426 
1427     Symbol *name = method->name();
1428 
1429     InstanceKlass* holder = method->method_holder();
1430     if (name == vmSymbols::runWith_method_name()) {
1431       if ((holder == resolver.Carrier_klass
1432            || holder == vmClasses::VirtualThread_klass()
1433            || holder == vmClasses::Thread_klass())) {
1434         loc = 1;
1435       }
1436     }
1437 
1438     if (loc != -1) {
1439       javaVFrame *frame = vfst.asJavaVFrame();
1440       StackValueCollection* locals = frame->locals();
1441       StackValue* head_sv = locals->at(loc); // jdk/incubator/concurrent/ScopedValue$Snapshot
1442       Handle result = head_sv->get_obj();
1443       assert(!head_sv->obj_is_scalar_replaced(), "found scalar-replaced object");
1444       if (result() != NULL) {
1445         return JNIHandles::make_local(THREAD, result());
1446       }
1447     }
1448   }
1449 
1450   return NULL;
1451 JVM_END
1452 
1453 JVM_ENTRY(jboolean, JVM_IsArrayClass(JNIEnv *env, jclass cls))
1454   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
1455   return (k != NULL) && k->is_array_klass() ? true : false;
1456 JVM_END
1457 
1458 
1459 JVM_ENTRY(jboolean, JVM_IsPrimitiveClass(JNIEnv *env, jclass cls))
1460   oop mirror = JNIHandles::resolve_non_null(cls);
1461   return (jboolean) java_lang_Class::is_primitive(mirror);
1462 JVM_END
1463 
1464 
1465 JVM_ENTRY(jint, JVM_GetClassModifiers(JNIEnv *env, jclass cls))
1466   oop mirror = JNIHandles::resolve_non_null(cls);
1467   if (java_lang_Class::is_primitive(mirror)) {
1468     // Primitive type
1469     return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC;
1470   }
1471 
1472   Klass* k = java_lang_Class::as_Klass(mirror);
1473   debug_only(int computed_modifiers = k->compute_modifier_flags());
1474   assert(k->modifier_flags() == computed_modifiers, "modifiers cache is OK");
1475   return k->modifier_flags();
1476 JVM_END
1477 
1478 
1479 // Inner class reflection ///////////////////////////////////////////////////////////////////////////////
1480 
1481 JVM_ENTRY(jobjectArray, JVM_GetDeclaredClasses(JNIEnv *env, jclass ofClass))
1482   JvmtiVMObjectAllocEventCollector oam;
1483   // ofClass is a reference to a java_lang_Class object. The mirror object
1484   // of an InstanceKlass
1485   oop ofMirror = JNIHandles::resolve_non_null(ofClass);
1486   if (java_lang_Class::is_primitive(ofMirror) ||
1487       ! java_lang_Class::as_Klass(ofMirror)->is_instance_klass()) {
1488     oop result = oopFactory::new_objArray(vmClasses::Class_klass(), 0, CHECK_NULL);
1489     return (jobjectArray)JNIHandles::make_local(THREAD, result);
1490   }
1491 
1492   InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(ofMirror));
1493   InnerClassesIterator iter(k);
1494 
1495   if (iter.length() == 0) {
1496     // Neither an inner nor outer class
1497     oop result = oopFactory::new_objArray(vmClasses::Class_klass(), 0, CHECK_NULL);
1498     return (jobjectArray)JNIHandles::make_local(THREAD, result);
1499   }
1500 
1501   // find inner class info
1502   constantPoolHandle cp(thread, k->constants());
1503   int length = iter.length();
1504 
1505   // Allocate temp. result array
1506   objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(), length/4, CHECK_NULL);
1507   objArrayHandle result (THREAD, r);
1508   int members = 0;
1509 
1510   for (; !iter.done(); iter.next()) {
1511     int ioff = iter.inner_class_info_index();
1512     int ooff = iter.outer_class_info_index();
1513 
1514     if (ioff != 0 && ooff != 0) {
1515       // Check to see if the name matches the class we're looking for
1516       // before attempting to find the class.
1517       if (cp->klass_name_at_matches(k, ooff)) {
1518         Klass* outer_klass = cp->klass_at(ooff, CHECK_NULL);
1519         if (outer_klass == k) {
1520            Klass* ik = cp->klass_at(ioff, CHECK_NULL);
1521            InstanceKlass* inner_klass = InstanceKlass::cast(ik);
1522 
1523            // Throws an exception if outer klass has not declared k as
1524            // an inner klass
1525            Reflection::check_for_inner_class(k, inner_klass, true, CHECK_NULL);
1526 
1527            result->obj_at_put(members, inner_klass->java_mirror());
1528            members++;
1529         }
1530       }
1531     }
1532   }
1533 
1534   if (members != length) {
1535     // Return array of right length
1536     objArrayOop res = oopFactory::new_objArray(vmClasses::Class_klass(), members, CHECK_NULL);
1537     for(int i = 0; i < members; i++) {
1538       res->obj_at_put(i, result->obj_at(i));
1539     }
1540     return (jobjectArray)JNIHandles::make_local(THREAD, res);
1541   }
1542 
1543   return (jobjectArray)JNIHandles::make_local(THREAD, result());
1544 JVM_END
1545 
1546 
1547 JVM_ENTRY(jclass, JVM_GetDeclaringClass(JNIEnv *env, jclass ofClass))
1548 {
1549   // ofClass is a reference to a java_lang_Class object.
1550   oop ofMirror = JNIHandles::resolve_non_null(ofClass);
1551   if (java_lang_Class::is_primitive(ofMirror)) {
1552     return NULL;
1553   }
1554   Klass* klass = java_lang_Class::as_Klass(ofMirror);
1555   if (!klass->is_instance_klass()) {
1556     return NULL;
1557   }
1558 
1559   bool inner_is_member = false;
1560   Klass* outer_klass
1561     = InstanceKlass::cast(klass)->compute_enclosing_class(&inner_is_member, CHECK_NULL);
1562   if (outer_klass == NULL)  return NULL;  // already a top-level class
1563   if (!inner_is_member)  return NULL;     // a hidden class (inside a method)
1564   return (jclass) JNIHandles::make_local(THREAD, outer_klass->java_mirror());
1565 }
1566 JVM_END
1567 
1568 JVM_ENTRY(jstring, JVM_GetSimpleBinaryName(JNIEnv *env, jclass cls))
1569 {
1570   oop mirror = JNIHandles::resolve_non_null(cls);
1571   if (java_lang_Class::is_primitive(mirror)) {
1572     return NULL;
1573   }
1574   Klass* klass = java_lang_Class::as_Klass(mirror);
1575   if (!klass->is_instance_klass()) {
1576     return NULL;
1577   }
1578   InstanceKlass* k = InstanceKlass::cast(klass);
1579   int ooff = 0, noff = 0;
1580   if (k->find_inner_classes_attr(&ooff, &noff, THREAD)) {
1581     if (noff != 0) {
1582       constantPoolHandle i_cp(thread, k->constants());
1583       Symbol* name = i_cp->symbol_at(noff);
1584       Handle str = java_lang_String::create_from_symbol(name, CHECK_NULL);
1585       return (jstring) JNIHandles::make_local(THREAD, str());
1586     }
1587   }
1588   return NULL;
1589 }
1590 JVM_END
1591 
1592 JVM_ENTRY(jstring, JVM_GetClassSignature(JNIEnv *env, jclass cls))
1593   assert (cls != NULL, "illegal class");
1594   JvmtiVMObjectAllocEventCollector oam;
1595   ResourceMark rm(THREAD);
1596   oop mirror = JNIHandles::resolve_non_null(cls);
1597   // Return null for arrays and primitives
1598   if (!java_lang_Class::is_primitive(mirror)) {
1599     Klass* k = java_lang_Class::as_Klass(mirror);
1600     if (k->is_instance_klass()) {
1601       Symbol* sym = InstanceKlass::cast(k)->generic_signature();
1602       if (sym == NULL) return NULL;
1603       Handle str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
1604       return (jstring) JNIHandles::make_local(THREAD, str());
1605     }
1606   }
1607   return NULL;
1608 JVM_END
1609 
1610 
1611 JVM_ENTRY(jbyteArray, JVM_GetClassAnnotations(JNIEnv *env, jclass cls))
1612   assert (cls != NULL, "illegal class");
1613   oop mirror = JNIHandles::resolve_non_null(cls);
1614   // Return null for arrays and primitives
1615   if (!java_lang_Class::is_primitive(mirror)) {
1616     Klass* k = java_lang_Class::as_Klass(mirror);
1617     if (k->is_instance_klass()) {
1618       typeArrayOop a = Annotations::make_java_array(InstanceKlass::cast(k)->class_annotations(), CHECK_NULL);
1619       return (jbyteArray) JNIHandles::make_local(THREAD, a);
1620     }
1621   }
1622   return NULL;
1623 JVM_END
1624 
1625 
1626 static bool jvm_get_field_common(jobject field, fieldDescriptor& fd) {
1627   // some of this code was adapted from from jni_FromReflectedField
1628 
1629   oop reflected = JNIHandles::resolve_non_null(field);
1630   oop mirror    = java_lang_reflect_Field::clazz(reflected);
1631   Klass* k    = java_lang_Class::as_Klass(mirror);
1632   int slot      = java_lang_reflect_Field::slot(reflected);
1633   int modifiers = java_lang_reflect_Field::modifiers(reflected);
1634 
1635   InstanceKlass* ik = InstanceKlass::cast(k);
1636   intptr_t offset = ik->field_offset(slot);
1637 
1638   if (modifiers & JVM_ACC_STATIC) {
1639     // for static fields we only look in the current class
1640     if (!ik->find_local_field_from_offset(offset, true, &fd)) {
1641       assert(false, "cannot find static field");
1642       return false;
1643     }
1644   } else {
1645     // for instance fields we start with the current class and work
1646     // our way up through the superclass chain
1647     if (!ik->find_field_from_offset(offset, false, &fd)) {
1648       assert(false, "cannot find instance field");
1649       return false;
1650     }
1651   }
1652   return true;
1653 }
1654 
1655 static Method* jvm_get_method_common(jobject method) {
1656   // some of this code was adapted from from jni_FromReflectedMethod
1657 
1658   oop reflected = JNIHandles::resolve_non_null(method);
1659   oop mirror    = NULL;
1660   int slot      = 0;
1661 
1662   if (reflected->klass() == vmClasses::reflect_Constructor_klass()) {
1663     mirror = java_lang_reflect_Constructor::clazz(reflected);
1664     slot   = java_lang_reflect_Constructor::slot(reflected);
1665   } else {
1666     assert(reflected->klass() == vmClasses::reflect_Method_klass(),
1667            "wrong type");
1668     mirror = java_lang_reflect_Method::clazz(reflected);
1669     slot   = java_lang_reflect_Method::slot(reflected);
1670   }
1671   Klass* k = java_lang_Class::as_Klass(mirror);
1672 
1673   Method* m = InstanceKlass::cast(k)->method_with_idnum(slot);
1674   assert(m != NULL, "cannot find method");
1675   return m;  // caller has to deal with NULL in product mode
1676 }
1677 
1678 /* Type use annotations support (JDK 1.8) */
1679 
1680 JVM_ENTRY(jbyteArray, JVM_GetClassTypeAnnotations(JNIEnv *env, jclass cls))
1681   assert (cls != NULL, "illegal class");
1682   ResourceMark rm(THREAD);
1683   // Return null for arrays and primitives
1684   if (!java_lang_Class::is_primitive(JNIHandles::resolve(cls))) {
1685     Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve(cls));
1686     if (k->is_instance_klass()) {
1687       AnnotationArray* type_annotations = InstanceKlass::cast(k)->class_type_annotations();
1688       if (type_annotations != NULL) {
1689         typeArrayOop a = Annotations::make_java_array(type_annotations, CHECK_NULL);
1690         return (jbyteArray) JNIHandles::make_local(THREAD, a);
1691       }
1692     }
1693   }
1694   return NULL;
1695 JVM_END
1696 
1697 JVM_ENTRY(jbyteArray, JVM_GetMethodTypeAnnotations(JNIEnv *env, jobject method))
1698   assert (method != NULL, "illegal method");
1699   // method is a handle to a java.lang.reflect.Method object
1700   Method* m = jvm_get_method_common(method);
1701   if (m == NULL) {
1702     return NULL;
1703   }
1704 
1705   AnnotationArray* type_annotations = m->type_annotations();
1706   if (type_annotations != NULL) {
1707     typeArrayOop a = Annotations::make_java_array(type_annotations, CHECK_NULL);
1708     return (jbyteArray) JNIHandles::make_local(THREAD, a);
1709   }
1710 
1711   return NULL;
1712 JVM_END
1713 
1714 JVM_ENTRY(jbyteArray, JVM_GetFieldTypeAnnotations(JNIEnv *env, jobject field))
1715   assert (field != NULL, "illegal field");
1716   fieldDescriptor fd;
1717   bool gotFd = jvm_get_field_common(field, fd);
1718   if (!gotFd) {
1719     return NULL;
1720   }
1721 
1722   return (jbyteArray) JNIHandles::make_local(THREAD, Annotations::make_java_array(fd.type_annotations(), THREAD));
1723 JVM_END
1724 
1725 static void bounds_check(const constantPoolHandle& cp, jint index, TRAPS) {
1726   if (!cp->is_within_bounds(index)) {
1727     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "Constant pool index out of bounds");
1728   }
1729 }
1730 
1731 JVM_ENTRY(jobjectArray, JVM_GetMethodParameters(JNIEnv *env, jobject method))
1732 {
1733   // method is a handle to a java.lang.reflect.Method object
1734   Method* method_ptr = jvm_get_method_common(method);
1735   methodHandle mh (THREAD, method_ptr);
1736   Handle reflected_method (THREAD, JNIHandles::resolve_non_null(method));
1737   const int num_params = mh->method_parameters_length();
1738 
1739   if (num_params < 0) {
1740     // A -1 return value from method_parameters_length means there is no
1741     // parameter data.  Return null to indicate this to the reflection
1742     // API.
1743     assert(num_params == -1, "num_params should be -1 if it is less than zero");
1744     return (jobjectArray)NULL;
1745   } else {
1746     // Otherwise, we return something up to reflection, even if it is
1747     // a zero-length array.  Why?  Because in some cases this can
1748     // trigger a MalformedParametersException.
1749 
1750     // make sure all the symbols are properly formatted
1751     for (int i = 0; i < num_params; i++) {
1752       MethodParametersElement* params = mh->method_parameters_start();
1753       int index = params[i].name_cp_index;
1754       constantPoolHandle cp(THREAD, mh->constants());
1755       bounds_check(cp, index, CHECK_NULL);
1756 
1757       if (0 != index && !mh->constants()->tag_at(index).is_utf8()) {
1758         THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(),
1759                     "Wrong type at constant pool index");
1760       }
1761 
1762     }
1763 
1764     objArrayOop result_oop = oopFactory::new_objArray(vmClasses::reflect_Parameter_klass(), num_params, CHECK_NULL);
1765     objArrayHandle result (THREAD, result_oop);
1766 
1767     for (int i = 0; i < num_params; i++) {
1768       MethodParametersElement* params = mh->method_parameters_start();
1769       // For a 0 index, give a NULL symbol
1770       Symbol* sym = 0 != params[i].name_cp_index ?
1771         mh->constants()->symbol_at(params[i].name_cp_index) : NULL;
1772       int flags = params[i].flags;
1773       oop param = Reflection::new_parameter(reflected_method, i, sym,
1774                                             flags, CHECK_NULL);
1775       result->obj_at_put(i, param);
1776     }
1777     return (jobjectArray)JNIHandles::make_local(THREAD, result());
1778   }
1779 }
1780 JVM_END
1781 
1782 // New (JDK 1.4) reflection implementation /////////////////////////////////////
1783 
1784 JVM_ENTRY(jobjectArray, JVM_GetClassDeclaredFields(JNIEnv *env, jclass ofClass, jboolean publicOnly))
1785 {
1786   JvmtiVMObjectAllocEventCollector oam;
1787 
1788   oop ofMirror = JNIHandles::resolve_non_null(ofClass);
1789   // Exclude primitive types and array types
1790   if (java_lang_Class::is_primitive(ofMirror) ||
1791       java_lang_Class::as_Klass(ofMirror)->is_array_klass()) {
1792     // Return empty array
1793     oop res = oopFactory::new_objArray(vmClasses::reflect_Field_klass(), 0, CHECK_NULL);
1794     return (jobjectArray) JNIHandles::make_local(THREAD, res);
1795   }
1796 
1797   InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(ofMirror));
1798   constantPoolHandle cp(THREAD, k->constants());
1799 
1800   // Ensure class is linked
1801   k->link_class(CHECK_NULL);
1802 
1803   // Allocate result
1804   int num_fields;
1805 
1806   if (publicOnly) {
1807     num_fields = 0;
1808     for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
1809       if (fs.access_flags().is_public()) ++num_fields;
1810     }
1811   } else {
1812     num_fields = k->java_fields_count();
1813   }
1814 
1815   objArrayOop r = oopFactory::new_objArray(vmClasses::reflect_Field_klass(), num_fields, CHECK_NULL);
1816   objArrayHandle result (THREAD, r);
1817 
1818   int out_idx = 0;
1819   fieldDescriptor fd;
1820   for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
1821     if (!publicOnly || fs.access_flags().is_public()) {
1822       fd.reinitialize(k, fs.index());
1823       oop field = Reflection::new_field(&fd, CHECK_NULL);
1824       result->obj_at_put(out_idx, field);
1825       ++out_idx;
1826     }
1827   }
1828   assert(out_idx == num_fields, "just checking");
1829   return (jobjectArray) JNIHandles::make_local(THREAD, result());
1830 }
1831 JVM_END
1832 
1833 // A class is a record if and only if it is final and a direct subclass of
1834 // java.lang.Record and has a Record attribute; otherwise, it is not a record.
1835 JVM_ENTRY(jboolean, JVM_IsRecord(JNIEnv *env, jclass cls))
1836 {
1837   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
1838   if (k != NULL && k->is_instance_klass()) {
1839     InstanceKlass* ik = InstanceKlass::cast(k);
1840     return ik->is_record();
1841   } else {
1842     return false;
1843   }
1844 }
1845 JVM_END
1846 
1847 // Returns an array containing the components of the Record attribute,
1848 // or NULL if the attribute is not present.
1849 //
1850 // Note that this function returns the components of the Record attribute
1851 // even if the class is not a record.
1852 JVM_ENTRY(jobjectArray, JVM_GetRecordComponents(JNIEnv* env, jclass ofClass))
1853 {
1854   Klass* c = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(ofClass));
1855   assert(c->is_instance_klass(), "must be");
1856   InstanceKlass* ik = InstanceKlass::cast(c);
1857 
1858   Array<RecordComponent*>* components = ik->record_components();
1859   if (components != NULL) {
1860     JvmtiVMObjectAllocEventCollector oam;
1861     constantPoolHandle cp(THREAD, ik->constants());
1862     int length = components->length();
1863     assert(length >= 0, "unexpected record_components length");
1864     objArrayOop record_components =
1865       oopFactory::new_objArray(vmClasses::RecordComponent_klass(), length, CHECK_NULL);
1866     objArrayHandle components_h (THREAD, record_components);
1867 
1868     for (int x = 0; x < length; x++) {
1869       RecordComponent* component = components->at(x);
1870       assert(component != NULL, "unexpected NULL record component");
1871       oop component_oop = java_lang_reflect_RecordComponent::create(ik, component, CHECK_NULL);
1872       components_h->obj_at_put(x, component_oop);
1873     }
1874     return (jobjectArray)JNIHandles::make_local(THREAD, components_h());
1875   }
1876 
1877   return NULL;
1878 }
1879 JVM_END
1880 
1881 static bool select_method(const methodHandle& method, bool want_constructor) {
1882   bool is_ctor = (method->is_object_constructor() ||
1883                   method->is_static_vnew_factory());
1884   if (want_constructor) {
1885     return is_ctor;
1886   } else {
1887     return (!is_ctor &&
1888             !method->is_class_initializer() &&
1889             !method->is_overpass());
1890   }
1891 }
1892 
1893 static jobjectArray get_class_declared_methods_helper(
1894                                   JNIEnv *env,
1895                                   jclass ofClass, jboolean publicOnly,
1896                                   bool want_constructor,
1897                                   Klass* klass, TRAPS) {
1898 
1899   JvmtiVMObjectAllocEventCollector oam;
1900 
1901   oop ofMirror = JNIHandles::resolve_non_null(ofClass);
1902   // Exclude primitive types and array types
1903   if (java_lang_Class::is_primitive(ofMirror)
1904       || java_lang_Class::as_Klass(ofMirror)->is_array_klass()) {
1905     // Return empty array
1906     oop res = oopFactory::new_objArray(klass, 0, CHECK_NULL);
1907     return (jobjectArray) JNIHandles::make_local(THREAD, res);
1908   }
1909 
1910   InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(ofMirror));
1911 
1912   // Ensure class is linked
1913   k->link_class(CHECK_NULL);
1914 
1915   Array<Method*>* methods = k->methods();
1916   int methods_length = methods->length();
1917 
1918   // Save original method_idnum in case of redefinition, which can change
1919   // the idnum of obsolete methods.  The new method will have the same idnum
1920   // but if we refresh the methods array, the counts will be wrong.
1921   ResourceMark rm(THREAD);
1922   GrowableArray<int>* idnums = new GrowableArray<int>(methods_length);
1923   int num_methods = 0;
1924 
1925   for (int i = 0; i < methods_length; i++) {
1926     methodHandle method(THREAD, methods->at(i));
1927     if (select_method(method, want_constructor)) {
1928       if (!publicOnly || method->is_public()) {
1929         idnums->push(method->method_idnum());
1930         ++num_methods;
1931       }
1932     }
1933   }
1934 
1935   // Allocate result
1936   objArrayOop r = oopFactory::new_objArray(klass, num_methods, CHECK_NULL);
1937   objArrayHandle result (THREAD, r);
1938 
1939   // Now just put the methods that we selected above, but go by their idnum
1940   // in case of redefinition.  The methods can be redefined at any safepoint,
1941   // so above when allocating the oop array and below when creating reflect
1942   // objects.
1943   for (int i = 0; i < num_methods; i++) {
1944     methodHandle method(THREAD, k->method_with_idnum(idnums->at(i)));
1945     if (method.is_null()) {
1946       // Method may have been deleted and seems this API can handle null
1947       // Otherwise should probably put a method that throws NSME
1948       result->obj_at_put(i, NULL);
1949     } else {
1950       oop m;
1951       if (want_constructor) {
1952         assert(method->is_object_constructor() ||
1953                method->is_static_vnew_factory(), "must be");
1954         m = Reflection::new_constructor(method, CHECK_NULL);
1955       } else {
1956         m = Reflection::new_method(method, false, CHECK_NULL);
1957       }
1958       result->obj_at_put(i, m);
1959     }
1960   }
1961 
1962   return (jobjectArray) JNIHandles::make_local(THREAD, result());
1963 }
1964 
1965 JVM_ENTRY(jobjectArray, JVM_GetClassDeclaredMethods(JNIEnv *env, jclass ofClass, jboolean publicOnly))
1966 {
1967   return get_class_declared_methods_helper(env, ofClass, publicOnly,
1968                                            /*want_constructor*/ false,
1969                                            vmClasses::reflect_Method_klass(), THREAD);
1970 }
1971 JVM_END
1972 
1973 JVM_ENTRY(jobjectArray, JVM_GetClassDeclaredConstructors(JNIEnv *env, jclass ofClass, jboolean publicOnly))
1974 {
1975   return get_class_declared_methods_helper(env, ofClass, publicOnly,
1976                                            /*want_constructor*/ true,
1977                                            vmClasses::reflect_Constructor_klass(), THREAD);
1978 }
1979 JVM_END
1980 
1981 JVM_ENTRY(jint, JVM_GetClassAccessFlags(JNIEnv *env, jclass cls))
1982 {
1983   oop mirror = JNIHandles::resolve_non_null(cls);
1984   if (java_lang_Class::is_primitive(mirror)) {
1985     // Primitive type
1986     return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC;
1987   }
1988 
1989   Klass* k = java_lang_Class::as_Klass(mirror);
1990   return k->access_flags().as_int() & JVM_ACC_WRITTEN_FLAGS;
1991 }
1992 JVM_END
1993 
1994 JVM_ENTRY(jboolean, JVM_AreNestMates(JNIEnv *env, jclass current, jclass member))
1995 {
1996   Klass* c = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(current));
1997   assert(c->is_instance_klass(), "must be");
1998   InstanceKlass* ck = InstanceKlass::cast(c);
1999   Klass* m = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(member));
2000   assert(m->is_instance_klass(), "must be");
2001   InstanceKlass* mk = InstanceKlass::cast(m);
2002   return ck->has_nestmate_access_to(mk, THREAD);
2003 }
2004 JVM_END
2005 
2006 JVM_ENTRY(jclass, JVM_GetNestHost(JNIEnv* env, jclass current))
2007 {
2008   // current is not a primitive or array class
2009   Klass* c = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(current));
2010   assert(c->is_instance_klass(), "must be");
2011   InstanceKlass* ck = InstanceKlass::cast(c);
2012   InstanceKlass* host = ck->nest_host(THREAD);
2013   return (jclass) (host == NULL ? NULL :
2014                    JNIHandles::make_local(THREAD, host->java_mirror()));
2015 }
2016 JVM_END
2017 
2018 JVM_ENTRY(jobjectArray, JVM_GetNestMembers(JNIEnv* env, jclass current))
2019 {
2020   // current is not a primitive or array class
2021   ResourceMark rm(THREAD);
2022   Klass* c = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(current));
2023   assert(c->is_instance_klass(), "must be");
2024   InstanceKlass* ck = InstanceKlass::cast(c);
2025   InstanceKlass* host = ck->nest_host(THREAD);
2026 
2027   log_trace(class, nestmates)("Calling GetNestMembers for type %s with nest-host %s",
2028                               ck->external_name(), host->external_name());
2029   {
2030     JvmtiVMObjectAllocEventCollector oam;
2031     Array<u2>* members = host->nest_members();
2032     int length = members == NULL ? 0 : members->length();
2033 
2034     log_trace(class, nestmates)(" - host has %d listed nest members", length);
2035 
2036     // nest host is first in the array so make it one bigger
2037     objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(),
2038                                              length + 1, CHECK_NULL);
2039     objArrayHandle result(THREAD, r);
2040     result->obj_at_put(0, host->java_mirror());
2041     if (length != 0) {
2042       int count = 0;
2043       for (int i = 0; i < length; i++) {
2044         int cp_index = members->at(i);
2045         Klass* k = host->constants()->klass_at(cp_index, THREAD);
2046         if (HAS_PENDING_EXCEPTION) {
2047           if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
2048             return NULL; // propagate VMEs
2049           }
2050           if (log_is_enabled(Trace, class, nestmates)) {
2051             stringStream ss;
2052             char* target_member_class = host->constants()->klass_name_at(cp_index)->as_C_string();
2053             ss.print(" - resolution of nest member %s failed: ", target_member_class);
2054             java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
2055             log_trace(class, nestmates)("%s", ss.as_string());
2056           }
2057           CLEAR_PENDING_EXCEPTION;
2058           continue;
2059         }
2060         if (k->is_instance_klass()) {
2061           InstanceKlass* ik = InstanceKlass::cast(k);
2062           InstanceKlass* nest_host_k = ik->nest_host(CHECK_NULL);
2063           if (nest_host_k == host) {
2064             result->obj_at_put(count+1, k->java_mirror());
2065             count++;
2066             log_trace(class, nestmates)(" - [%d] = %s", count, ik->external_name());
2067           } else {
2068             log_trace(class, nestmates)(" - skipping member %s with different host %s",
2069                                         ik->external_name(), nest_host_k->external_name());
2070           }
2071         } else {
2072           log_trace(class, nestmates)(" - skipping member %s that is not an instance class",
2073                                       k->external_name());
2074         }
2075       }
2076       if (count < length) {
2077         // we had invalid entries so we need to compact the array
2078         log_trace(class, nestmates)(" - compacting array from length %d to %d",
2079                                     length + 1, count + 1);
2080 
2081         objArrayOop r2 = oopFactory::new_objArray(vmClasses::Class_klass(),
2082                                                   count + 1, CHECK_NULL);
2083         objArrayHandle result2(THREAD, r2);
2084         for (int i = 0; i < count + 1; i++) {
2085           result2->obj_at_put(i, result->obj_at(i));
2086         }
2087         return (jobjectArray)JNIHandles::make_local(THREAD, result2());
2088       }
2089     }
2090     else {
2091       assert(host == ck || ck->is_hidden(), "must be singleton nest or dynamic nestmate");
2092     }
2093     return (jobjectArray)JNIHandles::make_local(THREAD, result());
2094   }
2095 }
2096 JVM_END
2097 
2098 JVM_ENTRY(jobjectArray, JVM_GetPermittedSubclasses(JNIEnv* env, jclass current))
2099 {
2100   oop mirror = JNIHandles::resolve_non_null(current);
2101   assert(!java_lang_Class::is_primitive(mirror), "should not be");
2102   Klass* c = java_lang_Class::as_Klass(mirror);
2103   assert(c->is_instance_klass(), "must be");
2104   InstanceKlass* ik = InstanceKlass::cast(c);
2105   ResourceMark rm(THREAD);
2106   log_trace(class, sealed)("Calling GetPermittedSubclasses for %s type %s",
2107                            ik->is_sealed() ? "sealed" : "non-sealed", ik->external_name());
2108   if (ik->is_sealed()) {
2109     JvmtiVMObjectAllocEventCollector oam;
2110     Array<u2>* subclasses = ik->permitted_subclasses();
2111     int length = subclasses->length();
2112 
2113     log_trace(class, sealed)(" - sealed class has %d permitted subclasses", length);
2114 
2115     objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(),
2116                                              length, CHECK_NULL);
2117     objArrayHandle result(THREAD, r);
2118     int count = 0;
2119     for (int i = 0; i < length; i++) {
2120       int cp_index = subclasses->at(i);
2121       Klass* k = ik->constants()->klass_at(cp_index, THREAD);
2122       if (HAS_PENDING_EXCEPTION) {
2123         if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
2124           return NULL; // propagate VMEs
2125         }
2126         if (log_is_enabled(Trace, class, sealed)) {
2127           stringStream ss;
2128           char* permitted_subclass = ik->constants()->klass_name_at(cp_index)->as_C_string();
2129           ss.print(" - resolution of permitted subclass %s failed: ", permitted_subclass);
2130           java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
2131           log_trace(class, sealed)("%s", ss.as_string());
2132         }
2133 
2134         CLEAR_PENDING_EXCEPTION;
2135         continue;
2136       }
2137       if (k->is_instance_klass()) {
2138         result->obj_at_put(count++, k->java_mirror());
2139         log_trace(class, sealed)(" - [%d] = %s", count, k->external_name());
2140       }
2141     }
2142     if (count < length) {
2143       // we had invalid entries so we need to compact the array
2144       objArrayOop r2 = oopFactory::new_objArray(vmClasses::Class_klass(),
2145                                                 count, CHECK_NULL);
2146       objArrayHandle result2(THREAD, r2);
2147       for (int i = 0; i < count; i++) {
2148         result2->obj_at_put(i, result->obj_at(i));
2149       }
2150       return (jobjectArray)JNIHandles::make_local(THREAD, result2());
2151     }
2152     return (jobjectArray)JNIHandles::make_local(THREAD, result());
2153   } else {
2154     return NULL;
2155   }
2156 }
2157 JVM_END
2158 
2159 // Constant pool access //////////////////////////////////////////////////////////
2160 
2161 JVM_ENTRY(jobject, JVM_GetClassConstantPool(JNIEnv *env, jclass cls))
2162 {
2163   JvmtiVMObjectAllocEventCollector oam;
2164   oop mirror = JNIHandles::resolve_non_null(cls);
2165   // Return null for primitives and arrays
2166   if (!java_lang_Class::is_primitive(mirror)) {
2167     Klass* k = java_lang_Class::as_Klass(mirror);
2168     if (k->is_instance_klass()) {
2169       InstanceKlass* k_h = InstanceKlass::cast(k);
2170       Handle jcp = reflect_ConstantPool::create(CHECK_NULL);
2171       reflect_ConstantPool::set_cp(jcp(), k_h->constants());
2172       return JNIHandles::make_local(THREAD, jcp());
2173     }
2174   }
2175   return NULL;
2176 }
2177 JVM_END
2178 
2179 
2180 JVM_ENTRY(jint, JVM_ConstantPoolGetSize(JNIEnv *env, jobject obj, jobject unused))
2181 {
2182   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2183   return cp->length();
2184 }
2185 JVM_END
2186 
2187 
2188 JVM_ENTRY(jclass, JVM_ConstantPoolGetClassAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2189 {
2190   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2191   bounds_check(cp, index, CHECK_NULL);
2192   constantTag tag = cp->tag_at(index);
2193   if (!tag.is_klass() && !tag.is_unresolved_klass()) {
2194     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2195   }
2196   Klass* k = cp->klass_at(index, CHECK_NULL);
2197   return (jclass) JNIHandles::make_local(THREAD, k->java_mirror());
2198 }
2199 JVM_END
2200 
2201 JVM_ENTRY(jclass, JVM_ConstantPoolGetClassAtIfLoaded(JNIEnv *env, jobject obj, jobject unused, jint index))
2202 {
2203   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2204   bounds_check(cp, index, CHECK_NULL);
2205   constantTag tag = cp->tag_at(index);
2206   if (!tag.is_klass() && !tag.is_unresolved_klass()) {
2207     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2208   }
2209   Klass* k = ConstantPool::klass_at_if_loaded(cp, index);
2210   if (k == NULL) return NULL;
2211   return (jclass) JNIHandles::make_local(THREAD, k->java_mirror());
2212 }
2213 JVM_END
2214 
2215 static jobject get_method_at_helper(const constantPoolHandle& cp, jint index, bool force_resolution, TRAPS) {
2216   constantTag tag = cp->tag_at(index);
2217   if (!tag.is_method() && !tag.is_interface_method()) {
2218     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2219   }
2220   int klass_ref  = cp->uncached_klass_ref_index_at(index);
2221   Klass* k_o;
2222   if (force_resolution) {
2223     k_o = cp->klass_at(klass_ref, CHECK_NULL);
2224   } else {
2225     k_o = ConstantPool::klass_at_if_loaded(cp, klass_ref);
2226     if (k_o == NULL) return NULL;
2227   }
2228   InstanceKlass* k = InstanceKlass::cast(k_o);
2229   Symbol* name = cp->uncached_name_ref_at(index);
2230   Symbol* sig  = cp->uncached_signature_ref_at(index);
2231   methodHandle m (THREAD, k->find_method(name, sig));
2232   if (m.is_null()) {
2233     THROW_MSG_0(vmSymbols::java_lang_RuntimeException(), "Unable to look up method in target class");
2234   }
2235   oop method;
2236   if (m->is_object_constructor() || m->is_static_vnew_factory()) {
2237     method = Reflection::new_constructor(m, CHECK_NULL);
2238   } else {
2239     method = Reflection::new_method(m, true, CHECK_NULL);
2240   }
2241   return JNIHandles::make_local(THREAD, method);
2242 }
2243 
2244 JVM_ENTRY(jobject, JVM_ConstantPoolGetMethodAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2245 {
2246   JvmtiVMObjectAllocEventCollector oam;
2247   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2248   bounds_check(cp, index, CHECK_NULL);
2249   jobject res = get_method_at_helper(cp, index, true, CHECK_NULL);
2250   return res;
2251 }
2252 JVM_END
2253 
2254 JVM_ENTRY(jobject, JVM_ConstantPoolGetMethodAtIfLoaded(JNIEnv *env, jobject obj, jobject unused, jint index))
2255 {
2256   JvmtiVMObjectAllocEventCollector oam;
2257   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2258   bounds_check(cp, index, CHECK_NULL);
2259   jobject res = get_method_at_helper(cp, index, false, CHECK_NULL);
2260   return res;
2261 }
2262 JVM_END
2263 
2264 static jobject get_field_at_helper(constantPoolHandle cp, jint index, bool force_resolution, TRAPS) {
2265   constantTag tag = cp->tag_at(index);
2266   if (!tag.is_field()) {
2267     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2268   }
2269   int klass_ref  = cp->uncached_klass_ref_index_at(index);
2270   Klass* k_o;
2271   if (force_resolution) {
2272     k_o = cp->klass_at(klass_ref, CHECK_NULL);
2273   } else {
2274     k_o = ConstantPool::klass_at_if_loaded(cp, klass_ref);
2275     if (k_o == NULL) return NULL;
2276   }
2277   InstanceKlass* k = InstanceKlass::cast(k_o);
2278   Symbol* name = cp->uncached_name_ref_at(index);
2279   Symbol* sig  = cp->uncached_signature_ref_at(index);
2280   fieldDescriptor fd;
2281   Klass* target_klass = k->find_field(name, sig, &fd);
2282   if (target_klass == NULL) {
2283     THROW_MSG_0(vmSymbols::java_lang_RuntimeException(), "Unable to look up field in target class");
2284   }
2285   oop field = Reflection::new_field(&fd, CHECK_NULL);
2286   return JNIHandles::make_local(THREAD, field);
2287 }
2288 
2289 JVM_ENTRY(jobject, JVM_ConstantPoolGetFieldAt(JNIEnv *env, jobject obj, jobject unusedl, jint index))
2290 {
2291   JvmtiVMObjectAllocEventCollector oam;
2292   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2293   bounds_check(cp, index, CHECK_NULL);
2294   jobject res = get_field_at_helper(cp, index, true, CHECK_NULL);
2295   return res;
2296 }
2297 JVM_END
2298 
2299 JVM_ENTRY(jobject, JVM_ConstantPoolGetFieldAtIfLoaded(JNIEnv *env, jobject obj, jobject unused, jint index))
2300 {
2301   JvmtiVMObjectAllocEventCollector oam;
2302   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2303   bounds_check(cp, index, CHECK_NULL);
2304   jobject res = get_field_at_helper(cp, index, false, CHECK_NULL);
2305   return res;
2306 }
2307 JVM_END
2308 
2309 JVM_ENTRY(jobjectArray, JVM_ConstantPoolGetMemberRefInfoAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2310 {
2311   JvmtiVMObjectAllocEventCollector oam;
2312   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2313   bounds_check(cp, index, CHECK_NULL);
2314   constantTag tag = cp->tag_at(index);
2315   if (!tag.is_field_or_method()) {
2316     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2317   }
2318   int klass_ref = cp->uncached_klass_ref_index_at(index);
2319   Symbol*  klass_name  = cp->klass_name_at(klass_ref);
2320   Symbol*  member_name = cp->uncached_name_ref_at(index);
2321   Symbol*  member_sig  = cp->uncached_signature_ref_at(index);
2322   objArrayOop  dest_o = oopFactory::new_objArray(vmClasses::String_klass(), 3, CHECK_NULL);
2323   objArrayHandle dest(THREAD, dest_o);
2324   Handle str = java_lang_String::create_from_symbol(klass_name, CHECK_NULL);
2325   dest->obj_at_put(0, str());
2326   str = java_lang_String::create_from_symbol(member_name, CHECK_NULL);
2327   dest->obj_at_put(1, str());
2328   str = java_lang_String::create_from_symbol(member_sig, CHECK_NULL);
2329   dest->obj_at_put(2, str());
2330   return (jobjectArray) JNIHandles::make_local(THREAD, dest());
2331 }
2332 JVM_END
2333 
2334 JVM_ENTRY(jint, JVM_ConstantPoolGetClassRefIndexAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2335 {
2336   JvmtiVMObjectAllocEventCollector oam;
2337   constantPoolHandle cp(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2338   bounds_check(cp, index, CHECK_0);
2339   constantTag tag = cp->tag_at(index);
2340   if (!tag.is_field_or_method()) {
2341     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2342   }
2343   return (jint) cp->uncached_klass_ref_index_at(index);
2344 }
2345 JVM_END
2346 
2347 JVM_ENTRY(jint, JVM_ConstantPoolGetNameAndTypeRefIndexAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2348 {
2349   JvmtiVMObjectAllocEventCollector oam;
2350   constantPoolHandle cp(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2351   bounds_check(cp, index, CHECK_0);
2352   constantTag tag = cp->tag_at(index);
2353   if (!tag.is_invoke_dynamic() && !tag.is_field_or_method()) {
2354     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2355   }
2356   return (jint) cp->uncached_name_and_type_ref_index_at(index);
2357 }
2358 JVM_END
2359 
2360 JVM_ENTRY(jobjectArray, JVM_ConstantPoolGetNameAndTypeRefInfoAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2361 {
2362   JvmtiVMObjectAllocEventCollector oam;
2363   constantPoolHandle cp(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2364   bounds_check(cp, index, CHECK_NULL);
2365   constantTag tag = cp->tag_at(index);
2366   if (!tag.is_name_and_type()) {
2367     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2368   }
2369   Symbol* member_name = cp->symbol_at(cp->name_ref_index_at(index));
2370   Symbol* member_sig = cp->symbol_at(cp->signature_ref_index_at(index));
2371   objArrayOop dest_o = oopFactory::new_objArray(vmClasses::String_klass(), 2, CHECK_NULL);
2372   objArrayHandle dest(THREAD, dest_o);
2373   Handle str = java_lang_String::create_from_symbol(member_name, CHECK_NULL);
2374   dest->obj_at_put(0, str());
2375   str = java_lang_String::create_from_symbol(member_sig, CHECK_NULL);
2376   dest->obj_at_put(1, str());
2377   return (jobjectArray) JNIHandles::make_local(THREAD, dest());
2378 }
2379 JVM_END
2380 
2381 JVM_ENTRY(jint, JVM_ConstantPoolGetIntAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2382 {
2383   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2384   bounds_check(cp, index, CHECK_0);
2385   constantTag tag = cp->tag_at(index);
2386   if (!tag.is_int()) {
2387     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2388   }
2389   return cp->int_at(index);
2390 }
2391 JVM_END
2392 
2393 JVM_ENTRY(jlong, JVM_ConstantPoolGetLongAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2394 {
2395   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2396   bounds_check(cp, index, CHECK_(0L));
2397   constantTag tag = cp->tag_at(index);
2398   if (!tag.is_long()) {
2399     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2400   }
2401   return cp->long_at(index);
2402 }
2403 JVM_END
2404 
2405 JVM_ENTRY(jfloat, JVM_ConstantPoolGetFloatAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2406 {
2407   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2408   bounds_check(cp, index, CHECK_(0.0f));
2409   constantTag tag = cp->tag_at(index);
2410   if (!tag.is_float()) {
2411     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2412   }
2413   return cp->float_at(index);
2414 }
2415 JVM_END
2416 
2417 JVM_ENTRY(jdouble, JVM_ConstantPoolGetDoubleAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2418 {
2419   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2420   bounds_check(cp, index, CHECK_(0.0));
2421   constantTag tag = cp->tag_at(index);
2422   if (!tag.is_double()) {
2423     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2424   }
2425   return cp->double_at(index);
2426 }
2427 JVM_END
2428 
2429 JVM_ENTRY(jstring, JVM_ConstantPoolGetStringAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2430 {
2431   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2432   bounds_check(cp, index, CHECK_NULL);
2433   constantTag tag = cp->tag_at(index);
2434   if (!tag.is_string()) {
2435     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2436   }
2437   oop str = cp->string_at(index, CHECK_NULL);
2438   return (jstring) JNIHandles::make_local(THREAD, str);
2439 }
2440 JVM_END
2441 
2442 JVM_ENTRY(jstring, JVM_ConstantPoolGetUTF8At(JNIEnv *env, jobject obj, jobject unused, jint index))
2443 {
2444   JvmtiVMObjectAllocEventCollector oam;
2445   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2446   bounds_check(cp, index, CHECK_NULL);
2447   constantTag tag = cp->tag_at(index);
2448   if (!tag.is_symbol()) {
2449     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2450   }
2451   Symbol* sym = cp->symbol_at(index);
2452   Handle str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
2453   return (jstring) JNIHandles::make_local(THREAD, str());
2454 }
2455 JVM_END
2456 
2457 JVM_ENTRY(jbyte, JVM_ConstantPoolGetTagAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2458 {
2459   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2460   bounds_check(cp, index, CHECK_0);
2461   constantTag tag = cp->tag_at(index);
2462   jbyte result = tag.value();
2463   // If returned tag values are not from the JVM spec, e.g. tags from 100 to 105,
2464   // they are changed to the corresponding tags from the JVM spec, so that java code in
2465   // sun.reflect.ConstantPool will return only tags from the JVM spec, not internal ones.
2466   if (tag.is_klass_or_reference()) {
2467       result = JVM_CONSTANT_Class;
2468   } else if (tag.is_string_index()) {
2469       result = JVM_CONSTANT_String;
2470   } else if (tag.is_method_type_in_error()) {
2471       result = JVM_CONSTANT_MethodType;
2472   } else if (tag.is_method_handle_in_error()) {
2473       result = JVM_CONSTANT_MethodHandle;
2474   } else if (tag.is_dynamic_constant_in_error()) {
2475       result = JVM_CONSTANT_Dynamic;
2476   }
2477   return result;
2478 }
2479 JVM_END
2480 
2481 // Assertion support. //////////////////////////////////////////////////////////
2482 
2483 JVM_ENTRY(jboolean, JVM_DesiredAssertionStatus(JNIEnv *env, jclass unused, jclass cls))
2484   assert(cls != NULL, "bad class");
2485 
2486   oop r = JNIHandles::resolve(cls);
2487   assert(! java_lang_Class::is_primitive(r), "primitive classes not allowed");
2488   if (java_lang_Class::is_primitive(r)) return false;
2489 
2490   Klass* k = java_lang_Class::as_Klass(r);
2491   assert(k->is_instance_klass(), "must be an instance klass");
2492   if (!k->is_instance_klass()) return false;
2493 
2494   ResourceMark rm(THREAD);
2495   const char* name = k->name()->as_C_string();
2496   bool system_class = k->class_loader() == NULL;
2497   return JavaAssertions::enabled(name, system_class);
2498 
2499 JVM_END
2500 
2501 
2502 // Return a new AssertionStatusDirectives object with the fields filled in with
2503 // command-line assertion arguments (i.e., -ea, -da).
2504 JVM_ENTRY(jobject, JVM_AssertionStatusDirectives(JNIEnv *env, jclass unused))
2505   JvmtiVMObjectAllocEventCollector oam;
2506   oop asd = JavaAssertions::createAssertionStatusDirectives(CHECK_NULL);
2507   return JNIHandles::make_local(THREAD, asd);
2508 JVM_END
2509 
2510 // Arrays support /////////////////////////////////////////////////////////////
2511 
2512 JVM_ENTRY(jboolean, JVM_ArrayIsAccessAtomic(JNIEnv *env, jclass unused, jobject array))
2513   oop o = JNIHandles::resolve(array);
2514   Klass* k = o->klass();
2515   if ((o == NULL) || (!k->is_array_klass())) {
2516     THROW_0(vmSymbols::java_lang_IllegalArgumentException());
2517   }
2518   return ArrayKlass::cast(k)->element_access_is_atomic();
2519 JVM_END
2520 
2521 JVM_ENTRY(jobject, JVM_ArrayEnsureAccessAtomic(JNIEnv *env, jclass unused, jobject array))
2522   oop o = JNIHandles::resolve(array);
2523   Klass* k = o->klass();
2524   if ((o == NULL) || (!k->is_array_klass())) {
2525     THROW_0(vmSymbols::java_lang_IllegalArgumentException());
2526   }
2527   if (k->is_flatArray_klass()) {
2528     FlatArrayKlass* vk = FlatArrayKlass::cast(k);
2529     if (!vk->element_access_is_atomic()) {
2530       /**
2531        * Need to decide how to implement:
2532        *
2533        * 1) Change to objArrayOop layout, therefore oop->klass() differs so
2534        * then "<atomic>[Qfoo;" klass needs to subclass "[Qfoo;" to pass through
2535        * "checkcast" & "instanceof"
2536        *
2537        * 2) Use extra header in the flatArrayOop to flag atomicity required and
2538        * possibly per instance lock structure. Said info, could be placed in
2539        * "trailer" rather than disturb the current arrayOop
2540        */
2541       Unimplemented();
2542     }
2543   }
2544   return array;
2545 JVM_END
2546 
2547 // Verification ////////////////////////////////////////////////////////////////////////////////
2548 
2549 // Reflection for the verifier /////////////////////////////////////////////////////////////////
2550 
2551 // RedefineClasses support: bug 6214132 caused verification to fail.
2552 // All functions from this section should call the jvmtiThreadSate function:
2553 //   Klass* class_to_verify_considering_redefinition(Klass* klass).
2554 // The function returns a Klass* of the _scratch_class if the verifier
2555 // was invoked in the middle of the class redefinition.
2556 // Otherwise it returns its argument value which is the _the_class Klass*.
2557 // Please, refer to the description in the jvmtiThreadSate.hpp.
2558 
2559 JVM_ENTRY(const char*, JVM_GetClassNameUTF(JNIEnv *env, jclass cls))
2560   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2561   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2562   return k->name()->as_utf8();
2563 JVM_END
2564 
2565 
2566 JVM_ENTRY(void, JVM_GetClassCPTypes(JNIEnv *env, jclass cls, unsigned char *types))
2567   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2568   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2569   // types will have length zero if this is not an InstanceKlass
2570   // (length is determined by call to JVM_GetClassCPEntriesCount)
2571   if (k->is_instance_klass()) {
2572     ConstantPool* cp = InstanceKlass::cast(k)->constants();
2573     for (int index = cp->length() - 1; index >= 0; index--) {
2574       constantTag tag = cp->tag_at(index);
2575       types[index] = (tag.is_unresolved_klass()) ? (unsigned char) JVM_CONSTANT_Class : tag.value();
2576     }
2577   }
2578 JVM_END
2579 
2580 
2581 JVM_ENTRY(jint, JVM_GetClassCPEntriesCount(JNIEnv *env, jclass cls))
2582   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2583   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2584   return (!k->is_instance_klass()) ? 0 : InstanceKlass::cast(k)->constants()->length();
2585 JVM_END
2586 
2587 
2588 JVM_ENTRY(jint, JVM_GetClassFieldsCount(JNIEnv *env, jclass cls))
2589   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2590   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2591   return (!k->is_instance_klass()) ? 0 : InstanceKlass::cast(k)->java_fields_count();
2592 JVM_END
2593 
2594 
2595 JVM_ENTRY(jint, JVM_GetClassMethodsCount(JNIEnv *env, jclass cls))
2596   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2597   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2598   return (!k->is_instance_klass()) ? 0 : InstanceKlass::cast(k)->methods()->length();
2599 JVM_END
2600 
2601 
2602 // The following methods, used for the verifier, are never called with
2603 // array klasses, so a direct cast to InstanceKlass is safe.
2604 // Typically, these methods are called in a loop with bounds determined
2605 // by the results of JVM_GetClass{Fields,Methods}Count, which return
2606 // zero for arrays.
2607 JVM_ENTRY(void, JVM_GetMethodIxExceptionIndexes(JNIEnv *env, jclass cls, jint method_index, unsigned short *exceptions))
2608   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2609   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2610   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2611   int length = method->checked_exceptions_length();
2612   if (length > 0) {
2613     CheckedExceptionElement* table= method->checked_exceptions_start();
2614     for (int i = 0; i < length; i++) {
2615       exceptions[i] = table[i].class_cp_index;
2616     }
2617   }
2618 JVM_END
2619 
2620 
2621 JVM_ENTRY(jint, JVM_GetMethodIxExceptionsCount(JNIEnv *env, jclass cls, jint method_index))
2622   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2623   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2624   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2625   return method->checked_exceptions_length();
2626 JVM_END
2627 
2628 
2629 JVM_ENTRY(void, JVM_GetMethodIxByteCode(JNIEnv *env, jclass cls, jint method_index, unsigned char *code))
2630   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2631   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2632   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2633   memcpy(code, method->code_base(), method->code_size());
2634 JVM_END
2635 
2636 
2637 JVM_ENTRY(jint, JVM_GetMethodIxByteCodeLength(JNIEnv *env, jclass cls, jint method_index))
2638   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2639   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2640   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2641   return method->code_size();
2642 JVM_END
2643 
2644 
2645 JVM_ENTRY(void, JVM_GetMethodIxExceptionTableEntry(JNIEnv *env, jclass cls, jint method_index, jint entry_index, JVM_ExceptionTableEntryType *entry))
2646   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2647   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2648   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2649   ExceptionTable extable(method);
2650   entry->start_pc   = extable.start_pc(entry_index);
2651   entry->end_pc     = extable.end_pc(entry_index);
2652   entry->handler_pc = extable.handler_pc(entry_index);
2653   entry->catchType  = extable.catch_type_index(entry_index);
2654 JVM_END
2655 
2656 
2657 JVM_ENTRY(jint, JVM_GetMethodIxExceptionTableLength(JNIEnv *env, jclass cls, int method_index))
2658   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2659   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2660   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2661   return method->exception_table_length();
2662 JVM_END
2663 
2664 
2665 JVM_ENTRY(jint, JVM_GetMethodIxModifiers(JNIEnv *env, jclass cls, int method_index))
2666   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2667   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2668   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2669   return method->access_flags().as_int() & JVM_RECOGNIZED_METHOD_MODIFIERS;
2670 JVM_END
2671 
2672 
2673 JVM_ENTRY(jint, JVM_GetFieldIxModifiers(JNIEnv *env, jclass cls, int field_index))
2674   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2675   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2676   return InstanceKlass::cast(k)->field_access_flags(field_index) & JVM_RECOGNIZED_FIELD_MODIFIERS;
2677 JVM_END
2678 
2679 
2680 JVM_ENTRY(jint, JVM_GetMethodIxLocalsCount(JNIEnv *env, jclass cls, int method_index))
2681   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2682   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2683   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2684   return method->max_locals();
2685 JVM_END
2686 
2687 
2688 JVM_ENTRY(jint, JVM_GetMethodIxArgsSize(JNIEnv *env, jclass cls, int method_index))
2689   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2690   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2691   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2692   return method->size_of_parameters();
2693 JVM_END
2694 
2695 
2696 JVM_ENTRY(jint, JVM_GetMethodIxMaxStack(JNIEnv *env, jclass cls, int method_index))
2697   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2698   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2699   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2700   return method->verifier_max_stack();
2701 JVM_END
2702 
2703 
2704 JVM_ENTRY(jboolean, JVM_IsConstructorIx(JNIEnv *env, jclass cls, int method_index))
2705   ResourceMark rm(THREAD);
2706   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2707   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2708   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2709   return method->is_object_constructor();
2710 JVM_END
2711 
2712 
2713 JVM_ENTRY(jboolean, JVM_IsVMGeneratedMethodIx(JNIEnv *env, jclass cls, int method_index))
2714   ResourceMark rm(THREAD);
2715   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2716   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2717   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2718   return method->is_overpass();
2719 JVM_END
2720 
2721 JVM_ENTRY(const char*, JVM_GetMethodIxNameUTF(JNIEnv *env, jclass cls, jint method_index))
2722   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2723   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2724   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2725   return method->name()->as_utf8();
2726 JVM_END
2727 
2728 
2729 JVM_ENTRY(const char*, JVM_GetMethodIxSignatureUTF(JNIEnv *env, jclass cls, jint method_index))
2730   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2731   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2732   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2733   return method->signature()->as_utf8();
2734 JVM_END
2735 
2736 /**
2737  * All of these JVM_GetCP-xxx methods are used by the old verifier to
2738  * read entries in the constant pool.  Since the old verifier always
2739  * works on a copy of the code, it will not see any rewriting that
2740  * may possibly occur in the middle of verification.  So it is important
2741  * that nothing it calls tries to use the cpCache instead of the raw
2742  * constant pool, so we must use cp->uncached_x methods when appropriate.
2743  */
2744 JVM_ENTRY(const char*, JVM_GetCPFieldNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2745   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2746   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2747   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2748   switch (cp->tag_at(cp_index).value()) {
2749     case JVM_CONSTANT_Fieldref:
2750       return cp->uncached_name_ref_at(cp_index)->as_utf8();
2751     default:
2752       fatal("JVM_GetCPFieldNameUTF: illegal constant");
2753   }
2754   ShouldNotReachHere();
2755   return NULL;
2756 JVM_END
2757 
2758 
2759 JVM_ENTRY(const char*, JVM_GetCPMethodNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2760   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2761   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2762   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2763   switch (cp->tag_at(cp_index).value()) {
2764     case JVM_CONSTANT_InterfaceMethodref:
2765     case JVM_CONSTANT_Methodref:
2766       return cp->uncached_name_ref_at(cp_index)->as_utf8();
2767     default:
2768       fatal("JVM_GetCPMethodNameUTF: illegal constant");
2769   }
2770   ShouldNotReachHere();
2771   return NULL;
2772 JVM_END
2773 
2774 
2775 JVM_ENTRY(const char*, JVM_GetCPMethodSignatureUTF(JNIEnv *env, jclass cls, jint cp_index))
2776   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2777   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2778   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2779   switch (cp->tag_at(cp_index).value()) {
2780     case JVM_CONSTANT_InterfaceMethodref:
2781     case JVM_CONSTANT_Methodref:
2782       return cp->uncached_signature_ref_at(cp_index)->as_utf8();
2783     default:
2784       fatal("JVM_GetCPMethodSignatureUTF: illegal constant");
2785   }
2786   ShouldNotReachHere();
2787   return NULL;
2788 JVM_END
2789 
2790 
2791 JVM_ENTRY(const char*, JVM_GetCPFieldSignatureUTF(JNIEnv *env, jclass cls, jint cp_index))
2792   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2793   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2794   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2795   switch (cp->tag_at(cp_index).value()) {
2796     case JVM_CONSTANT_Fieldref:
2797       return cp->uncached_signature_ref_at(cp_index)->as_utf8();
2798     default:
2799       fatal("JVM_GetCPFieldSignatureUTF: illegal constant");
2800   }
2801   ShouldNotReachHere();
2802   return NULL;
2803 JVM_END
2804 
2805 
2806 JVM_ENTRY(const char*, JVM_GetCPClassNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2807   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2808   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2809   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2810   Symbol* classname = cp->klass_name_at(cp_index);
2811   return classname->as_utf8();
2812 JVM_END
2813 
2814 
2815 JVM_ENTRY(const char*, JVM_GetCPFieldClassNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2816   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2817   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2818   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2819   switch (cp->tag_at(cp_index).value()) {
2820     case JVM_CONSTANT_Fieldref: {
2821       int class_index = cp->uncached_klass_ref_index_at(cp_index);
2822       Symbol* classname = cp->klass_name_at(class_index);
2823       return classname->as_utf8();
2824     }
2825     default:
2826       fatal("JVM_GetCPFieldClassNameUTF: illegal constant");
2827   }
2828   ShouldNotReachHere();
2829   return NULL;
2830 JVM_END
2831 
2832 
2833 JVM_ENTRY(const char*, JVM_GetCPMethodClassNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2834   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2835   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2836   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2837   switch (cp->tag_at(cp_index).value()) {
2838     case JVM_CONSTANT_Methodref:
2839     case JVM_CONSTANT_InterfaceMethodref: {
2840       int class_index = cp->uncached_klass_ref_index_at(cp_index);
2841       Symbol* classname = cp->klass_name_at(class_index);
2842       return classname->as_utf8();
2843     }
2844     default:
2845       fatal("JVM_GetCPMethodClassNameUTF: illegal constant");
2846   }
2847   ShouldNotReachHere();
2848   return NULL;
2849 JVM_END
2850 
2851 
2852 JVM_ENTRY(jint, JVM_GetCPFieldModifiers(JNIEnv *env, jclass cls, int cp_index, jclass called_cls))
2853   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2854   Klass* k_called = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(called_cls));
2855   k        = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2856   k_called = JvmtiThreadState::class_to_verify_considering_redefinition(k_called, thread);
2857   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2858   ConstantPool* cp_called = InstanceKlass::cast(k_called)->constants();
2859   switch (cp->tag_at(cp_index).value()) {
2860     case JVM_CONSTANT_Fieldref: {
2861       Symbol* name      = cp->uncached_name_ref_at(cp_index);
2862       Symbol* signature = cp->uncached_signature_ref_at(cp_index);
2863       InstanceKlass* ik = InstanceKlass::cast(k_called);
2864       for (JavaFieldStream fs(ik); !fs.done(); fs.next()) {
2865         if (fs.name() == name && fs.signature() == signature) {
2866           return fs.access_flags().as_short() & JVM_RECOGNIZED_FIELD_MODIFIERS;
2867         }
2868       }
2869       return -1;
2870     }
2871     default:
2872       fatal("JVM_GetCPFieldModifiers: illegal constant");
2873   }
2874   ShouldNotReachHere();
2875   return 0;
2876 JVM_END
2877 
2878 
2879 JVM_ENTRY(jint, JVM_GetCPMethodModifiers(JNIEnv *env, jclass cls, int cp_index, jclass called_cls))
2880   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2881   Klass* k_called = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(called_cls));
2882   k        = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2883   k_called = JvmtiThreadState::class_to_verify_considering_redefinition(k_called, thread);
2884   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2885   switch (cp->tag_at(cp_index).value()) {
2886     case JVM_CONSTANT_Methodref:
2887     case JVM_CONSTANT_InterfaceMethodref: {
2888       Symbol* name      = cp->uncached_name_ref_at(cp_index);
2889       Symbol* signature = cp->uncached_signature_ref_at(cp_index);
2890       Array<Method*>* methods = InstanceKlass::cast(k_called)->methods();
2891       int methods_count = methods->length();
2892       for (int i = 0; i < methods_count; i++) {
2893         Method* method = methods->at(i);
2894         if (method->name() == name && method->signature() == signature) {
2895             return method->access_flags().as_int() & JVM_RECOGNIZED_METHOD_MODIFIERS;
2896         }
2897       }
2898       return -1;
2899     }
2900     default:
2901       fatal("JVM_GetCPMethodModifiers: illegal constant");
2902   }
2903   ShouldNotReachHere();
2904   return 0;
2905 JVM_END
2906 
2907 
2908 // Misc //////////////////////////////////////////////////////////////////////////////////////////////
2909 
2910 JVM_LEAF(void, JVM_ReleaseUTF(const char *utf))
2911   // So long as UTF8::convert_to_utf8 returns resource strings, we don't have to do anything
2912 JVM_END
2913 
2914 
2915 JVM_ENTRY(jboolean, JVM_IsSameClassPackage(JNIEnv *env, jclass class1, jclass class2))
2916   oop class1_mirror = JNIHandles::resolve_non_null(class1);
2917   oop class2_mirror = JNIHandles::resolve_non_null(class2);
2918   Klass* klass1 = java_lang_Class::as_Klass(class1_mirror);
2919   Klass* klass2 = java_lang_Class::as_Klass(class2_mirror);
2920   return (jboolean) Reflection::is_same_class_package(klass1, klass2);
2921 JVM_END
2922 
2923 // Printing support //////////////////////////////////////////////////
2924 extern "C" {
2925 
2926 ATTRIBUTE_PRINTF(3, 0)
2927 int jio_vsnprintf(char *str, size_t count, const char *fmt, va_list args) {
2928   // Reject count values that are negative signed values converted to
2929   // unsigned; see bug 4399518, 4417214
2930   if ((intptr_t)count <= 0) return -1;
2931 
2932   int result = os::vsnprintf(str, count, fmt, args);
2933   if (result > 0 && (size_t)result >= count) {
2934     result = -1;
2935   }
2936 
2937   return result;
2938 }
2939 
2940 ATTRIBUTE_PRINTF(3, 4)
2941 int jio_snprintf(char *str, size_t count, const char *fmt, ...) {
2942   va_list args;
2943   int len;
2944   va_start(args, fmt);
2945   len = jio_vsnprintf(str, count, fmt, args);
2946   va_end(args);
2947   return len;
2948 }
2949 
2950 ATTRIBUTE_PRINTF(2, 3)
2951 int jio_fprintf(FILE* f, const char *fmt, ...) {
2952   int len;
2953   va_list args;
2954   va_start(args, fmt);
2955   len = jio_vfprintf(f, fmt, args);
2956   va_end(args);
2957   return len;
2958 }
2959 
2960 ATTRIBUTE_PRINTF(2, 0)
2961 int jio_vfprintf(FILE* f, const char *fmt, va_list args) {
2962   if (Arguments::vfprintf_hook() != NULL) {
2963      return Arguments::vfprintf_hook()(f, fmt, args);
2964   } else {
2965     return vfprintf(f, fmt, args);
2966   }
2967 }
2968 
2969 ATTRIBUTE_PRINTF(1, 2)
2970 JNIEXPORT int jio_printf(const char *fmt, ...) {
2971   int len;
2972   va_list args;
2973   va_start(args, fmt);
2974   len = jio_vfprintf(defaultStream::output_stream(), fmt, args);
2975   va_end(args);
2976   return len;
2977 }
2978 
2979 // HotSpot specific jio method
2980 void jio_print(const char* s, size_t len) {
2981   // Try to make this function as atomic as possible.
2982   if (Arguments::vfprintf_hook() != NULL) {
2983     jio_fprintf(defaultStream::output_stream(), "%.*s", (int)len, s);
2984   } else {
2985     // Make an unused local variable to avoid warning from gcc compiler.
2986     ssize_t count = os::write(defaultStream::output_fd(), s, (int)len);
2987   }
2988 }
2989 
2990 } // Extern C
2991 
2992 // java.lang.Thread //////////////////////////////////////////////////////////////////////////////
2993 
2994 // In most of the JVM thread support functions we need to access the
2995 // thread through a ThreadsListHandle to prevent it from exiting and
2996 // being reclaimed while we try to operate on it. The exceptions to this
2997 // rule are when operating on the current thread, or if the monitor of
2998 // the target java.lang.Thread is locked at the Java level - in both
2999 // cases the target cannot exit.
3000 
3001 static void thread_entry(JavaThread* thread, TRAPS) {
3002   HandleMark hm(THREAD);
3003   Handle obj(THREAD, thread->threadObj());
3004   JavaValue result(T_VOID);
3005   JavaCalls::call_virtual(&result,
3006                           obj,
3007                           vmClasses::Thread_klass(),
3008                           vmSymbols::run_method_name(),
3009                           vmSymbols::void_method_signature(),
3010                           THREAD);
3011 }
3012 
3013 
3014 JVM_ENTRY(void, JVM_StartThread(JNIEnv* env, jobject jthread))
3015 #if INCLUDE_CDS
3016   if (DumpSharedSpaces) {
3017     // During java -Xshare:dump, if we allow multiple Java threads to
3018     // execute in parallel, symbols and classes may be loaded in
3019     // random orders which will make the resulting CDS archive
3020     // non-deterministic.
3021     //
3022     // Lucikly, during java -Xshare:dump, it's important to run only
3023     // the code in the main Java thread (which is NOT started here) that
3024     // creates the module graph, etc. It's safe to not start the other
3025     // threads which are launched by class static initializers
3026     // (ReferenceHandler, FinalizerThread and CleanerImpl).
3027     if (log_is_enabled(Info, cds)) {
3028       ResourceMark rm;
3029       oop t = JNIHandles::resolve_non_null(jthread);
3030       log_info(cds)("JVM_StartThread() ignored: %s", t->klass()->external_name());
3031     }
3032     return;
3033   }
3034 #endif
3035   JavaThread *native_thread = NULL;
3036 
3037   // We cannot hold the Threads_lock when we throw an exception,
3038   // due to rank ordering issues. Example:  we might need to grab the
3039   // Heap_lock while we construct the exception.
3040   bool throw_illegal_thread_state = false;
3041 
3042   // We must release the Threads_lock before we can post a jvmti event
3043   // in Thread::start.
3044   {
3045     // Ensure that the C++ Thread and OSThread structures aren't freed before
3046     // we operate.
3047     MutexLocker mu(Threads_lock);
3048 
3049     // Since JDK 5 the java.lang.Thread threadStatus is used to prevent
3050     // re-starting an already started thread, so we should usually find
3051     // that the JavaThread is null. However for a JNI attached thread
3052     // there is a small window between the Thread object being created
3053     // (with its JavaThread set) and the update to its threadStatus, so we
3054     // have to check for this
3055     if (java_lang_Thread::thread(JNIHandles::resolve_non_null(jthread)) != NULL) {
3056       throw_illegal_thread_state = true;
3057     } else {
3058       jlong size =
3059              java_lang_Thread::stackSize(JNIHandles::resolve_non_null(jthread));
3060       // Allocate the C++ Thread structure and create the native thread.  The
3061       // stack size retrieved from java is 64-bit signed, but the constructor takes
3062       // size_t (an unsigned type), which may be 32 or 64-bit depending on the platform.
3063       //  - Avoid truncating on 32-bit platforms if size is greater than UINT_MAX.
3064       //  - Avoid passing negative values which would result in really large stacks.
3065       NOT_LP64(if (size > SIZE_MAX) size = SIZE_MAX;)
3066       size_t sz = size > 0 ? (size_t) size : 0;
3067       native_thread = new JavaThread(&thread_entry, sz);
3068 
3069       // At this point it may be possible that no osthread was created for the
3070       // JavaThread due to lack of memory. Check for this situation and throw
3071       // an exception if necessary. Eventually we may want to change this so
3072       // that we only grab the lock if the thread was created successfully -
3073       // then we can also do this check and throw the exception in the
3074       // JavaThread constructor.
3075       if (native_thread->osthread() != NULL) {
3076         // Note: the current thread is not being used within "prepare".
3077         native_thread->prepare(jthread);
3078       }
3079     }
3080   }
3081 
3082   if (throw_illegal_thread_state) {
3083     THROW(vmSymbols::java_lang_IllegalThreadStateException());
3084   }
3085 
3086   assert(native_thread != NULL, "Starting null thread?");
3087 
3088   if (native_thread->osthread() == NULL) {
3089     ResourceMark rm(thread);
3090     log_warning(os, thread)("Failed to start the native thread for java.lang.Thread \"%s\"",
3091                             JavaThread::name_for(JNIHandles::resolve_non_null(jthread)));
3092     // No one should hold a reference to the 'native_thread'.
3093     native_thread->smr_delete();
3094     if (JvmtiExport::should_post_resource_exhausted()) {
3095       JvmtiExport::post_resource_exhausted(
3096         JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_THREADS,
3097         os::native_thread_creation_failed_msg());
3098     }
3099     THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(),
3100               os::native_thread_creation_failed_msg());
3101   }
3102 
3103   JFR_ONLY(Jfr::on_java_thread_start(thread, native_thread);)
3104 
3105   Thread::start(native_thread);
3106 
3107 JVM_END
3108 
3109 
3110 JVM_ENTRY(jboolean, JVM_IsThreadAlive(JNIEnv* env, jobject jthread))
3111   oop thread_oop = JNIHandles::resolve_non_null(jthread);
3112   return java_lang_Thread::is_alive(thread_oop);
3113 JVM_END
3114 
3115 
3116 JVM_ENTRY(void, JVM_SetThreadPriority(JNIEnv* env, jobject jthread, jint prio))
3117   ThreadsListHandle tlh(thread);
3118   oop java_thread = NULL;
3119   JavaThread* receiver = NULL;
3120   bool is_alive = tlh.cv_internal_thread_to_JavaThread(jthread, &receiver, &java_thread);
3121   java_lang_Thread::set_priority(java_thread, (ThreadPriority)prio);
3122 
3123   if (is_alive) {
3124     // jthread refers to a live JavaThread.
3125     Thread::set_priority(receiver, (ThreadPriority)prio);
3126   }
3127   // Implied else: If the JavaThread hasn't started yet, then the
3128   // priority set in the java.lang.Thread object above will be pushed
3129   // down when it does start.
3130 JVM_END
3131 
3132 
3133 JVM_LEAF(void, JVM_Yield(JNIEnv *env, jclass threadClass))
3134   if (os::dont_yield()) return;
3135   HOTSPOT_THREAD_YIELD();
3136   os::naked_yield();
3137 JVM_END
3138 
3139 JVM_ENTRY(void, JVM_Sleep(JNIEnv* env, jclass threadClass, jlong millis))
3140   if (millis < 0) {
3141     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "timeout value is negative");
3142   }
3143 
3144   if (thread->is_interrupted(true) && !HAS_PENDING_EXCEPTION) {
3145     THROW_MSG(vmSymbols::java_lang_InterruptedException(), "sleep interrupted");
3146   }
3147 
3148   // Save current thread state and restore it at the end of this block.
3149   // And set new thread state to SLEEPING.
3150   JavaThreadSleepState jtss(thread);
3151 
3152   HOTSPOT_THREAD_SLEEP_BEGIN(millis);
3153 
3154   if (millis == 0) {
3155     os::naked_yield();
3156   } else {
3157     ThreadState old_state = thread->osthread()->get_state();
3158     thread->osthread()->set_state(SLEEPING);
3159     if (!thread->sleep(millis)) { // interrupted
3160       // An asynchronous exception could have been thrown on
3161       // us while we were sleeping. We do not overwrite those.
3162       if (!HAS_PENDING_EXCEPTION) {
3163         HOTSPOT_THREAD_SLEEP_END(1);
3164 
3165         // TODO-FIXME: THROW_MSG returns which means we will not call set_state()
3166         // to properly restore the thread state.  That's likely wrong.
3167         THROW_MSG(vmSymbols::java_lang_InterruptedException(), "sleep interrupted");
3168       }
3169     }
3170     thread->osthread()->set_state(old_state);
3171   }
3172   HOTSPOT_THREAD_SLEEP_END(0);
3173 JVM_END
3174 
3175 JVM_ENTRY(jobject, JVM_CurrentCarrierThread(JNIEnv* env, jclass threadClass))
3176   oop jthread = thread->threadObj();
3177   assert(jthread != NULL, "no current carrier thread!");
3178   return JNIHandles::make_local(THREAD, jthread);
3179 JVM_END
3180 
3181 JVM_ENTRY(jobject, JVM_CurrentThread(JNIEnv* env, jclass threadClass))
3182   oop theThread = thread->vthread();
3183   assert(theThread != (oop)NULL, "no current thread!");
3184   return JNIHandles::make_local(THREAD, theThread);
3185 JVM_END
3186 
3187 JVM_ENTRY(void, JVM_SetCurrentThread(JNIEnv* env, jobject thisThread,
3188                                      jobject theThread))
3189   oop threadObj = JNIHandles::resolve(theThread);
3190   thread->set_vthread(threadObj);
3191   JFR_ONLY(Jfr::on_set_current_thread(thread, threadObj);)
3192 JVM_END
3193 
3194 JVM_ENTRY(jlong, JVM_GetNextThreadIdOffset(JNIEnv* env, jclass threadClass))
3195   return ThreadIdentifier::unsafe_offset();
3196 JVM_END
3197 
3198 JVM_ENTRY(void, JVM_Interrupt(JNIEnv* env, jobject jthread))
3199   ThreadsListHandle tlh(thread);
3200   JavaThread* receiver = NULL;
3201   bool is_alive = tlh.cv_internal_thread_to_JavaThread(jthread, &receiver, NULL);
3202   if (is_alive) {
3203     // jthread refers to a live JavaThread.
3204     receiver->interrupt();
3205   }
3206 JVM_END
3207 
3208 // Return true iff the current thread has locked the object passed in
3209 
3210 JVM_ENTRY(jboolean, JVM_HoldsLock(JNIEnv* env, jclass threadClass, jobject obj))
3211   if (obj == NULL) {
3212     THROW_(vmSymbols::java_lang_NullPointerException(), JNI_FALSE);
3213   }
3214   Handle h_obj(THREAD, JNIHandles::resolve(obj));
3215   return ObjectSynchronizer::current_thread_holds_lock(thread, h_obj);
3216 JVM_END
3217 
3218 JVM_ENTRY(jobject, JVM_GetStackTrace(JNIEnv *env, jobject jthread))
3219   oop trace = java_lang_Thread::async_get_stack_trace(JNIHandles::resolve(jthread), THREAD);
3220   return JNIHandles::make_local(THREAD, trace);
3221 JVM_END
3222 
3223 JVM_ENTRY(void, JVM_DumpAllStacks(JNIEnv* env, jclass))
3224   VM_PrintThreads op;
3225   VMThread::execute(&op);
3226   if (JvmtiExport::should_post_data_dump()) {
3227     JvmtiExport::post_data_dump();
3228   }
3229 JVM_END
3230 
3231 JVM_ENTRY(void, JVM_SetNativeThreadName(JNIEnv* env, jobject jthread, jstring name))
3232   // We don't use a ThreadsListHandle here because the current thread
3233   // must be alive.
3234   oop java_thread = JNIHandles::resolve_non_null(jthread);
3235   JavaThread* thr = java_lang_Thread::thread(java_thread);
3236   if (thread == thr && !thr->has_attached_via_jni()) {
3237     // Thread naming is only supported for the current thread and
3238     // we don't set the name of an attached thread to avoid stepping
3239     // on other programs.
3240     ResourceMark rm(thread);
3241     const char *thread_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
3242     os::set_native_thread_name(thread_name);
3243   }
3244 JVM_END
3245 
3246 JVM_ENTRY(jobject, JVM_ScopedValueCache(JNIEnv* env, jclass threadClass))
3247   oop theCache = thread->scopedValueCache();
3248   return JNIHandles::make_local(THREAD, theCache);
3249 JVM_END
3250 
3251 JVM_ENTRY(void, JVM_SetScopedValueCache(JNIEnv* env, jclass threadClass,
3252                                        jobject theCache))
3253   arrayOop objs = arrayOop(JNIHandles::resolve(theCache));
3254   thread->set_scopedValueCache(objs);
3255 JVM_END
3256 
3257 // java.lang.SecurityManager ///////////////////////////////////////////////////////////////////////
3258 
3259 JVM_ENTRY(jobjectArray, JVM_GetClassContext(JNIEnv *env))
3260   ResourceMark rm(THREAD);
3261   JvmtiVMObjectAllocEventCollector oam;
3262   vframeStream vfst(thread);
3263 
3264   if (vmClasses::reflect_CallerSensitive_klass() != NULL) {
3265     // This must only be called from SecurityManager.getClassContext
3266     Method* m = vfst.method();
3267     if (!(m->method_holder() == vmClasses::SecurityManager_klass() &&
3268           m->name()          == vmSymbols::getClassContext_name() &&
3269           m->signature()     == vmSymbols::void_class_array_signature())) {
3270       THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "JVM_GetClassContext must only be called from SecurityManager.getClassContext");
3271     }
3272   }
3273 
3274   // Collect method holders
3275   GrowableArray<Klass*>* klass_array = new GrowableArray<Klass*>();
3276   for (; !vfst.at_end(); vfst.security_next()) {
3277     Method* m = vfst.method();
3278     // Native frames are not returned
3279     if (!m->is_ignored_by_security_stack_walk() && !m->is_native()) {
3280       Klass* holder = m->method_holder();
3281       assert(holder->is_klass(), "just checking");
3282       klass_array->append(holder);
3283     }
3284   }
3285 
3286   // Create result array of type [Ljava/lang/Class;
3287   objArrayOop result = oopFactory::new_objArray(vmClasses::Class_klass(), klass_array->length(), CHECK_NULL);
3288   // Fill in mirrors corresponding to method holders
3289   for (int i = 0; i < klass_array->length(); i++) {
3290     result->obj_at_put(i, klass_array->at(i)->java_mirror());
3291   }
3292 
3293   return (jobjectArray) JNIHandles::make_local(THREAD, result);
3294 JVM_END
3295 
3296 
3297 // java.lang.Package ////////////////////////////////////////////////////////////////
3298 
3299 
3300 JVM_ENTRY(jstring, JVM_GetSystemPackage(JNIEnv *env, jstring name))
3301   ResourceMark rm(THREAD);
3302   JvmtiVMObjectAllocEventCollector oam;
3303   char* str = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
3304   oop result = ClassLoader::get_system_package(str, CHECK_NULL);
3305 return (jstring) JNIHandles::make_local(THREAD, result);
3306 JVM_END
3307 
3308 
3309 JVM_ENTRY(jobjectArray, JVM_GetSystemPackages(JNIEnv *env))
3310   JvmtiVMObjectAllocEventCollector oam;
3311   objArrayOop result = ClassLoader::get_system_packages(CHECK_NULL);
3312   return (jobjectArray) JNIHandles::make_local(THREAD, result);
3313 JVM_END
3314 
3315 
3316 // java.lang.ref.Reference ///////////////////////////////////////////////////////////////
3317 
3318 
3319 JVM_ENTRY(jobject, JVM_GetAndClearReferencePendingList(JNIEnv* env))
3320   MonitorLocker ml(Heap_lock);
3321   oop ref = Universe::reference_pending_list();
3322   if (ref != NULL) {
3323     Universe::clear_reference_pending_list();
3324   }
3325   return JNIHandles::make_local(THREAD, ref);
3326 JVM_END
3327 
3328 JVM_ENTRY(jboolean, JVM_HasReferencePendingList(JNIEnv* env))
3329   MonitorLocker ml(Heap_lock);
3330   return Universe::has_reference_pending_list();
3331 JVM_END
3332 
3333 JVM_ENTRY(void, JVM_WaitForReferencePendingList(JNIEnv* env))
3334   MonitorLocker ml(Heap_lock);
3335   while (!Universe::has_reference_pending_list()) {
3336     ml.wait();
3337   }
3338 JVM_END
3339 
3340 JVM_ENTRY(jboolean, JVM_ReferenceRefersTo(JNIEnv* env, jobject ref, jobject o))
3341   oop ref_oop = JNIHandles::resolve_non_null(ref);
3342   // PhantomReference has it's own implementation of refersTo().
3343   // See: JVM_PhantomReferenceRefersTo
3344   assert(!java_lang_ref_Reference::is_phantom(ref_oop), "precondition");
3345   oop referent = java_lang_ref_Reference::weak_referent_no_keepalive(ref_oop);
3346   return referent == JNIHandles::resolve(o);
3347 JVM_END
3348 
3349 JVM_ENTRY(void, JVM_ReferenceClear(JNIEnv* env, jobject ref))
3350   oop ref_oop = JNIHandles::resolve_non_null(ref);
3351   // FinalReference has it's own implementation of clear().
3352   assert(!java_lang_ref_Reference::is_final(ref_oop), "precondition");
3353   if (java_lang_ref_Reference::unknown_referent_no_keepalive(ref_oop) == NULL) {
3354     // If the referent has already been cleared then done.
3355     // However, if the referent is dead but has not yet been cleared by
3356     // concurrent reference processing, it should NOT be cleared here.
3357     // Instead, clearing should be left to the GC.  Clearing it here could
3358     // detectably lose an expected notification, which is impossible with
3359     // STW reference processing.  The clearing in enqueue() doesn't have
3360     // this problem, since the enqueue covers the notification, but it's not
3361     // worth the effort to handle that case specially.
3362     return;
3363   }
3364   java_lang_ref_Reference::clear_referent(ref_oop);
3365 JVM_END
3366 
3367 
3368 // java.lang.ref.PhantomReference //////////////////////////////////////////////////
3369 
3370 
3371 JVM_ENTRY(jboolean, JVM_PhantomReferenceRefersTo(JNIEnv* env, jobject ref, jobject o))
3372   oop ref_oop = JNIHandles::resolve_non_null(ref);
3373   oop referent = java_lang_ref_Reference::phantom_referent_no_keepalive(ref_oop);
3374   return referent == JNIHandles::resolve(o);
3375 JVM_END
3376 
3377 
3378 // ObjectInputStream ///////////////////////////////////////////////////////////////
3379 
3380 // Return the first user-defined class loader up the execution stack, or null
3381 // if only code from the bootstrap or platform class loader is on the stack.
3382 
3383 JVM_ENTRY(jobject, JVM_LatestUserDefinedLoader(JNIEnv *env))
3384   for (vframeStream vfst(thread); !vfst.at_end(); vfst.next()) {
3385     InstanceKlass* ik = vfst.method()->method_holder();
3386     oop loader = ik->class_loader();
3387     if (loader != NULL && !SystemDictionary::is_platform_class_loader(loader)) {
3388       // Skip reflection related frames
3389       if (!ik->is_subclass_of(vmClasses::reflect_MethodAccessorImpl_klass()) &&
3390           !ik->is_subclass_of(vmClasses::reflect_ConstructorAccessorImpl_klass())) {
3391         return JNIHandles::make_local(THREAD, loader);
3392       }
3393     }
3394   }
3395   return NULL;
3396 JVM_END
3397 
3398 
3399 // Array ///////////////////////////////////////////////////////////////////////////////////////////
3400 
3401 
3402 // resolve array handle and check arguments
3403 static inline arrayOop check_array(JNIEnv *env, jobject arr, bool type_array_only, TRAPS) {
3404   if (arr == NULL) {
3405     THROW_0(vmSymbols::java_lang_NullPointerException());
3406   }
3407   oop a = JNIHandles::resolve_non_null(arr);
3408   if (!a->is_array()) {
3409     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Argument is not an array");
3410   } else if (type_array_only && !a->is_typeArray()) {
3411     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Argument is not an array of primitive type");
3412   }
3413   return arrayOop(a);
3414 }
3415 
3416 
3417 JVM_ENTRY(jint, JVM_GetArrayLength(JNIEnv *env, jobject arr))
3418   arrayOop a = check_array(env, arr, false, CHECK_0);
3419   return a->length();
3420 JVM_END
3421 
3422 
3423 JVM_ENTRY(jobject, JVM_GetArrayElement(JNIEnv *env, jobject arr, jint index))
3424   JvmtiVMObjectAllocEventCollector oam;
3425   arrayOop a = check_array(env, arr, false, CHECK_NULL);
3426   jvalue value;
3427   BasicType type = Reflection::array_get(&value, a, index, CHECK_NULL);
3428   oop box = Reflection::box(&value, type, CHECK_NULL);
3429   return JNIHandles::make_local(THREAD, box);
3430 JVM_END
3431 
3432 
3433 JVM_ENTRY(jvalue, JVM_GetPrimitiveArrayElement(JNIEnv *env, jobject arr, jint index, jint wCode))
3434   jvalue value;
3435   value.i = 0; // to initialize value before getting used in CHECK
3436   arrayOop a = check_array(env, arr, true, CHECK_(value));
3437   assert(a->is_typeArray(), "just checking");
3438   BasicType type = Reflection::array_get(&value, a, index, CHECK_(value));
3439   BasicType wide_type = (BasicType) wCode;
3440   if (type != wide_type) {
3441     Reflection::widen(&value, type, wide_type, CHECK_(value));
3442   }
3443   return value;
3444 JVM_END
3445 
3446 
3447 JVM_ENTRY(void, JVM_SetArrayElement(JNIEnv *env, jobject arr, jint index, jobject val))
3448   arrayOop a = check_array(env, arr, false, CHECK);
3449   oop box = JNIHandles::resolve(val);
3450   jvalue value;
3451   value.i = 0; // to initialize value before getting used in CHECK
3452   BasicType value_type;
3453   if (a->is_objArray()) {
3454     // Make sure we do no unbox e.g. java/lang/Integer instances when storing into an object array
3455     value_type = Reflection::unbox_for_regular_object(box, &value);
3456   } else {
3457     value_type = Reflection::unbox_for_primitive(box, &value, CHECK);
3458   }
3459   Reflection::array_set(&value, a, index, value_type, CHECK);
3460 JVM_END
3461 
3462 
3463 JVM_ENTRY(void, JVM_SetPrimitiveArrayElement(JNIEnv *env, jobject arr, jint index, jvalue v, unsigned char vCode))
3464   arrayOop a = check_array(env, arr, true, CHECK);
3465   assert(a->is_typeArray(), "just checking");
3466   BasicType value_type = (BasicType) vCode;
3467   Reflection::array_set(&v, a, index, value_type, CHECK);
3468 JVM_END
3469 
3470 
3471 JVM_ENTRY(jobject, JVM_NewArray(JNIEnv *env, jclass eltClass, jint length))
3472   JvmtiVMObjectAllocEventCollector oam;
3473   oop element_mirror = JNIHandles::resolve(eltClass);
3474   oop result = Reflection::reflect_new_array(element_mirror, length, CHECK_NULL);
3475   return JNIHandles::make_local(THREAD, result);
3476 JVM_END
3477 
3478 
3479 JVM_ENTRY(jobject, JVM_NewMultiArray(JNIEnv *env, jclass eltClass, jintArray dim))
3480   JvmtiVMObjectAllocEventCollector oam;
3481   arrayOop dim_array = check_array(env, dim, true, CHECK_NULL);
3482   oop element_mirror = JNIHandles::resolve(eltClass);
3483   assert(dim_array->is_typeArray(), "just checking");
3484   oop result = Reflection::reflect_new_multi_array(element_mirror, typeArrayOop(dim_array), CHECK_NULL);
3485   return JNIHandles::make_local(THREAD, result);
3486 JVM_END
3487 
3488 
3489 // Library support ///////////////////////////////////////////////////////////////////////////
3490 
3491 JVM_LEAF(void*, JVM_LoadZipLibrary())
3492   ClassLoader::load_zip_library_if_needed();
3493   return ClassLoader::zip_library_handle();
3494 JVM_END
3495 
3496 JVM_ENTRY_NO_ENV(void*, JVM_LoadLibrary(const char* name, jboolean throwException))
3497   //%note jvm_ct
3498   char ebuf[1024];
3499   void *load_result;
3500   {
3501     ThreadToNativeFromVM ttnfvm(thread);
3502     load_result = os::dll_load(name, ebuf, sizeof ebuf);
3503   }
3504   if (load_result == NULL) {
3505     if (throwException) {
3506       char msg[1024];
3507       jio_snprintf(msg, sizeof msg, "%s: %s", name, ebuf);
3508       // Since 'ebuf' may contain a string encoded using
3509       // platform encoding scheme, we need to pass
3510       // Exceptions::unsafe_to_utf8 to the new_exception method
3511       // as the last argument. See bug 6367357.
3512       Handle h_exception =
3513         Exceptions::new_exception(thread,
3514                                   vmSymbols::java_lang_UnsatisfiedLinkError(),
3515                                   msg, Exceptions::unsafe_to_utf8);
3516 
3517       THROW_HANDLE_0(h_exception);
3518     } else {
3519       log_info(library)("Failed to load library %s", name);
3520       return load_result;
3521     }
3522   }
3523   log_info(library)("Loaded library %s, handle " INTPTR_FORMAT, name, p2i(load_result));
3524   return load_result;
3525 JVM_END
3526 
3527 
3528 JVM_LEAF(void, JVM_UnloadLibrary(void* handle))
3529   os::dll_unload(handle);
3530   log_info(library)("Unloaded library with handle " INTPTR_FORMAT, p2i(handle));
3531 JVM_END
3532 
3533 
3534 JVM_LEAF(void*, JVM_FindLibraryEntry(void* handle, const char* name))
3535   void* find_result = os::dll_lookup(handle, name);
3536   log_info(library)("%s %s in library with handle " INTPTR_FORMAT,
3537                     find_result != NULL ? "Found" : "Failed to find",
3538                     name, p2i(handle));
3539   return find_result;
3540 JVM_END
3541 
3542 
3543 // JNI version ///////////////////////////////////////////////////////////////////////////////
3544 
3545 JVM_LEAF(jboolean, JVM_IsSupportedJNIVersion(jint version))
3546   return Threads::is_supported_jni_version_including_1_1(version);
3547 JVM_END
3548 
3549 
3550 JVM_LEAF(jboolean, JVM_IsPreviewEnabled(void))
3551   return Arguments::enable_preview() ? JNI_TRUE : JNI_FALSE;
3552 JVM_END
3553 
3554 JVM_LEAF(jboolean, JVM_IsValhallaEnabled(void))
3555   return EnableValhalla ? JNI_TRUE : JNI_FALSE;
3556 JVM_END
3557 
3558 JVM_LEAF(jboolean, JVM_IsContinuationsSupported(void))
3559   return VMContinuations ? JNI_TRUE : JNI_FALSE;
3560 JVM_END
3561 
3562 // String support ///////////////////////////////////////////////////////////////////////////
3563 
3564 JVM_ENTRY(jstring, JVM_InternString(JNIEnv *env, jstring str))
3565   JvmtiVMObjectAllocEventCollector oam;
3566   if (str == NULL) return NULL;
3567   oop string = JNIHandles::resolve_non_null(str);
3568   oop result = StringTable::intern(string, CHECK_NULL);
3569   return (jstring) JNIHandles::make_local(THREAD, result);
3570 JVM_END
3571 
3572 
3573 // VM Raw monitor support //////////////////////////////////////////////////////////////////////
3574 
3575 // VM Raw monitors (not to be confused with JvmtiRawMonitors) are a simple mutual exclusion
3576 // lock (not actually monitors: no wait/notify) that is exported by the VM for use by JDK
3577 // library code. They may be used by JavaThreads and non-JavaThreads and do not participate
3578 // in the safepoint protocol, thread suspension, thread interruption, or anything of that
3579 // nature. JavaThreads will be "in native" when using this API from JDK code.
3580 
3581 
3582 JNIEXPORT void* JNICALL JVM_RawMonitorCreate(void) {
3583   VM_Exit::block_if_vm_exited();
3584   return new PlatformMutex();
3585 }
3586 
3587 
3588 JNIEXPORT void JNICALL  JVM_RawMonitorDestroy(void *mon) {
3589   VM_Exit::block_if_vm_exited();
3590   delete ((PlatformMutex*) mon);
3591 }
3592 
3593 
3594 JNIEXPORT jint JNICALL JVM_RawMonitorEnter(void *mon) {
3595   VM_Exit::block_if_vm_exited();
3596   ((PlatformMutex*) mon)->lock();
3597   return 0;
3598 }
3599 
3600 
3601 JNIEXPORT void JNICALL JVM_RawMonitorExit(void *mon) {
3602   VM_Exit::block_if_vm_exited();
3603   ((PlatformMutex*) mon)->unlock();
3604 }
3605 
3606 
3607 // Shared JNI/JVM entry points //////////////////////////////////////////////////////////////
3608 
3609 jclass find_class_from_class_loader(JNIEnv* env, Symbol* name, jboolean init,
3610                                     Handle loader, Handle protection_domain,
3611                                     jboolean throwError, TRAPS) {
3612   // Security Note:
3613   //   The Java level wrapper will perform the necessary security check allowing
3614   //   us to pass the NULL as the initiating class loader.  The VM is responsible for
3615   //   the checkPackageAccess relative to the initiating class loader via the
3616   //   protection_domain. The protection_domain is passed as NULL by the java code
3617   //   if there is no security manager in 3-arg Class.forName().
3618   Klass* klass = SystemDictionary::resolve_or_fail(name, loader, protection_domain, throwError != 0, CHECK_NULL);
3619 
3620   // Check if we should initialize the class
3621   if (init && klass->is_instance_klass()) {
3622     klass->initialize(CHECK_NULL);
3623   }
3624   return (jclass) JNIHandles::make_local(THREAD, klass->java_mirror());
3625 }
3626 
3627 
3628 // Method ///////////////////////////////////////////////////////////////////////////////////////////
3629 
3630 JVM_ENTRY(jobject, JVM_InvokeMethod(JNIEnv *env, jobject method, jobject obj, jobjectArray args0))
3631   Handle method_handle;
3632   if (thread->stack_overflow_state()->stack_available((address) &method_handle) >= JVMInvokeMethodSlack) {
3633     method_handle = Handle(THREAD, JNIHandles::resolve(method));
3634     Handle receiver(THREAD, JNIHandles::resolve(obj));
3635     objArrayHandle args = oopFactory::ensure_objArray(JNIHandles::resolve(args0), CHECK_NULL);
3636     oop result = Reflection::invoke_method(method_handle(), receiver, args, CHECK_NULL);
3637     jobject res = JNIHandles::make_local(THREAD, result);
3638     if (JvmtiExport::should_post_vm_object_alloc()) {
3639       oop ret_type = java_lang_reflect_Method::return_type(method_handle());
3640       assert(ret_type != NULL, "sanity check: ret_type oop must not be NULL!");
3641       if (java_lang_Class::is_primitive(ret_type)) {
3642         // Only for primitive type vm allocates memory for java object.
3643         // See box() method.
3644         JvmtiExport::post_vm_object_alloc(thread, result);
3645       }
3646     }
3647     return res;
3648   } else {
3649     THROW_0(vmSymbols::java_lang_StackOverflowError());
3650   }
3651 JVM_END
3652 
3653 
3654 JVM_ENTRY(jobject, JVM_NewInstanceFromConstructor(JNIEnv *env, jobject c, jobjectArray args0))
3655   objArrayHandle args = oopFactory::ensure_objArray(JNIHandles::resolve(args0), CHECK_NULL);
3656   oop constructor_mirror = JNIHandles::resolve(c);
3657   oop result = Reflection::invoke_constructor(constructor_mirror, args, CHECK_NULL);
3658   jobject res = JNIHandles::make_local(THREAD, result);
3659   if (JvmtiExport::should_post_vm_object_alloc()) {
3660     JvmtiExport::post_vm_object_alloc(thread, result);
3661   }
3662   return res;
3663 JVM_END
3664 
3665 // Atomic ///////////////////////////////////////////////////////////////////////////////////////////
3666 
3667 JVM_LEAF(jboolean, JVM_SupportsCX8())
3668   return VM_Version::supports_cx8();
3669 JVM_END
3670 
3671 JVM_ENTRY(void, JVM_InitializeFromArchive(JNIEnv* env, jclass cls))
3672   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve(cls));
3673   assert(k->is_klass(), "just checking");
3674   HeapShared::initialize_from_archived_subgraph(THREAD, k);
3675 JVM_END
3676 
3677 JVM_ENTRY(void, JVM_RegisterLambdaProxyClassForArchiving(JNIEnv* env,
3678                                               jclass caller,
3679                                               jstring interfaceMethodName,
3680                                               jobject factoryType,
3681                                               jobject interfaceMethodType,
3682                                               jobject implementationMember,
3683                                               jobject dynamicMethodType,
3684                                               jclass lambdaProxyClass))
3685 #if INCLUDE_CDS
3686   if (!Arguments::is_dumping_archive()) {
3687     return;
3688   }
3689 
3690   Klass* caller_k = java_lang_Class::as_Klass(JNIHandles::resolve(caller));
3691   InstanceKlass* caller_ik = InstanceKlass::cast(caller_k);
3692   if (caller_ik->is_hidden()) {
3693     // Hidden classes not of type lambda proxy classes are currently not being archived.
3694     // If the caller_ik is of one of the above types, the corresponding lambda proxy class won't be
3695     // registered for archiving.
3696     return;
3697   }
3698   Klass* lambda_k = java_lang_Class::as_Klass(JNIHandles::resolve(lambdaProxyClass));
3699   InstanceKlass* lambda_ik = InstanceKlass::cast(lambda_k);
3700   assert(lambda_ik->is_hidden(), "must be a hidden class");
3701   assert(!lambda_ik->is_non_strong_hidden(), "expected a strong hidden class");
3702 
3703   Symbol* interface_method_name = NULL;
3704   if (interfaceMethodName != NULL) {
3705     interface_method_name = java_lang_String::as_symbol(JNIHandles::resolve_non_null(interfaceMethodName));
3706   }
3707   Handle factory_type_oop(THREAD, JNIHandles::resolve_non_null(factoryType));
3708   Symbol* factory_type = java_lang_invoke_MethodType::as_signature(factory_type_oop(), true);
3709 
3710   Handle interface_method_type_oop(THREAD, JNIHandles::resolve_non_null(interfaceMethodType));
3711   Symbol* interface_method_type = java_lang_invoke_MethodType::as_signature(interface_method_type_oop(), true);
3712 
3713   Handle implementation_member_oop(THREAD, JNIHandles::resolve_non_null(implementationMember));
3714   assert(java_lang_invoke_MemberName::is_method(implementation_member_oop()), "must be");
3715   Method* m = java_lang_invoke_MemberName::vmtarget(implementation_member_oop());
3716 
3717   Handle dynamic_method_type_oop(THREAD, JNIHandles::resolve_non_null(dynamicMethodType));
3718   Symbol* dynamic_method_type = java_lang_invoke_MethodType::as_signature(dynamic_method_type_oop(), true);
3719 
3720   SystemDictionaryShared::add_lambda_proxy_class(caller_ik, lambda_ik, interface_method_name, factory_type,
3721                                                  interface_method_type, m, dynamic_method_type, THREAD);
3722 #endif // INCLUDE_CDS
3723 JVM_END
3724 
3725 JVM_ENTRY(jclass, JVM_LookupLambdaProxyClassFromArchive(JNIEnv* env,
3726                                                         jclass caller,
3727                                                         jstring interfaceMethodName,
3728                                                         jobject factoryType,
3729                                                         jobject interfaceMethodType,
3730                                                         jobject implementationMember,
3731                                                         jobject dynamicMethodType))
3732 #if INCLUDE_CDS
3733 
3734   if (interfaceMethodName == NULL || factoryType == NULL || interfaceMethodType == NULL ||
3735       implementationMember == NULL || dynamicMethodType == NULL) {
3736     THROW_(vmSymbols::java_lang_NullPointerException(), NULL);
3737   }
3738 
3739   Klass* caller_k = java_lang_Class::as_Klass(JNIHandles::resolve(caller));
3740   InstanceKlass* caller_ik = InstanceKlass::cast(caller_k);
3741   if (!caller_ik->is_shared()) {
3742     // there won't be a shared lambda class if the caller_ik is not in the shared archive.
3743     return NULL;
3744   }
3745 
3746   Symbol* interface_method_name = java_lang_String::as_symbol(JNIHandles::resolve_non_null(interfaceMethodName));
3747   Handle factory_type_oop(THREAD, JNIHandles::resolve_non_null(factoryType));
3748   Symbol* factory_type = java_lang_invoke_MethodType::as_signature(factory_type_oop(), true);
3749 
3750   Handle interface_method_type_oop(THREAD, JNIHandles::resolve_non_null(interfaceMethodType));
3751   Symbol* interface_method_type = java_lang_invoke_MethodType::as_signature(interface_method_type_oop(), true);
3752 
3753   Handle implementation_member_oop(THREAD, JNIHandles::resolve_non_null(implementationMember));
3754   assert(java_lang_invoke_MemberName::is_method(implementation_member_oop()), "must be");
3755   Method* m = java_lang_invoke_MemberName::vmtarget(implementation_member_oop());
3756 
3757   Handle dynamic_method_type_oop(THREAD, JNIHandles::resolve_non_null(dynamicMethodType));
3758   Symbol* dynamic_method_type = java_lang_invoke_MethodType::as_signature(dynamic_method_type_oop(), true);
3759 
3760   InstanceKlass* lambda_ik = SystemDictionaryShared::get_shared_lambda_proxy_class(caller_ik, interface_method_name, factory_type,
3761                                                                                    interface_method_type, m, dynamic_method_type);
3762   jclass jcls = NULL;
3763   if (lambda_ik != NULL) {
3764     InstanceKlass* loaded_lambda = SystemDictionaryShared::prepare_shared_lambda_proxy_class(lambda_ik, caller_ik, THREAD);
3765     jcls = loaded_lambda == NULL ? NULL : (jclass) JNIHandles::make_local(THREAD, loaded_lambda->java_mirror());
3766   }
3767   return jcls;
3768 #else
3769   return NULL;
3770 #endif // INCLUDE_CDS
3771 JVM_END
3772 
3773 JVM_LEAF(jboolean, JVM_IsCDSDumpingEnabled(JNIEnv* env))
3774   return Arguments::is_dumping_archive();
3775 JVM_END
3776 
3777 JVM_LEAF(jboolean, JVM_IsSharingEnabled(JNIEnv* env))
3778   return UseSharedSpaces;
3779 JVM_END
3780 
3781 JVM_ENTRY_NO_ENV(jlong, JVM_GetRandomSeedForDumping())
3782   if (DumpSharedSpaces) {
3783     const char* release = VM_Version::vm_release();
3784     const char* dbg_level = VM_Version::jdk_debug_level();
3785     const char* version = VM_Version::internal_vm_info_string();
3786     jlong seed = (jlong)(java_lang_String::hash_code((const jbyte*)release, (int)strlen(release)) ^
3787                          java_lang_String::hash_code((const jbyte*)dbg_level, (int)strlen(dbg_level)) ^
3788                          java_lang_String::hash_code((const jbyte*)version, (int)strlen(version)));
3789     seed += (jlong)VM_Version::vm_major_version();
3790     seed += (jlong)VM_Version::vm_minor_version();
3791     seed += (jlong)VM_Version::vm_security_version();
3792     seed += (jlong)VM_Version::vm_patch_version();
3793     if (seed == 0) { // don't let this ever be zero.
3794       seed = 0x87654321;
3795     }
3796     log_debug(cds)("JVM_GetRandomSeedForDumping() = " JLONG_FORMAT, seed);
3797     return seed;
3798   } else {
3799     return 0;
3800   }
3801 JVM_END
3802 
3803 JVM_LEAF(jboolean, JVM_IsDumpingClassList(JNIEnv *env))
3804 #if INCLUDE_CDS
3805   return ClassListWriter::is_enabled() || DynamicDumpSharedSpaces;
3806 #else
3807   return false;
3808 #endif // INCLUDE_CDS
3809 JVM_END
3810 
3811 JVM_ENTRY(void, JVM_LogLambdaFormInvoker(JNIEnv *env, jstring line))
3812 #if INCLUDE_CDS
3813   assert(ClassListWriter::is_enabled() || DynamicDumpSharedSpaces,  "Should be set and open or do dynamic dump");
3814   if (line != NULL) {
3815     ResourceMark rm(THREAD);
3816     Handle h_line (THREAD, JNIHandles::resolve_non_null(line));
3817     char* c_line = java_lang_String::as_utf8_string(h_line());
3818     if (DynamicDumpSharedSpaces) {
3819       // Note: LambdaFormInvokers::append take same format which is not
3820       // same as below the print format. The line does not include LAMBDA_FORM_TAG.
3821       LambdaFormInvokers::append(os::strdup((const char*)c_line, mtInternal));
3822     }
3823     if (ClassListWriter::is_enabled()) {
3824       ClassListWriter w;
3825       w.stream()->print_cr("%s %s", LAMBDA_FORM_TAG, c_line);
3826     }
3827   }
3828 #endif // INCLUDE_CDS
3829 JVM_END
3830 
3831 JVM_ENTRY(void, JVM_DumpClassListToFile(JNIEnv *env, jstring listFileName))
3832 #if INCLUDE_CDS
3833   ResourceMark rm(THREAD);
3834   Handle file_handle(THREAD, JNIHandles::resolve_non_null(listFileName));
3835   char* file_name  = java_lang_String::as_utf8_string(file_handle());
3836   MetaspaceShared::dump_loaded_classes(file_name, THREAD);
3837 #endif // INCLUDE_CDS
3838 JVM_END
3839 
3840 JVM_ENTRY(void, JVM_DumpDynamicArchive(JNIEnv *env, jstring archiveName))
3841 #if INCLUDE_CDS
3842   ResourceMark rm(THREAD);
3843   Handle file_handle(THREAD, JNIHandles::resolve_non_null(archiveName));
3844   char* archive_name  = java_lang_String::as_utf8_string(file_handle());
3845   DynamicArchive::dump_for_jcmd(archive_name, CHECK);
3846 #endif // INCLUDE_CDS
3847 JVM_END
3848 
3849 // Returns an array of all live Thread objects (VM internal JavaThreads,
3850 // jvmti agent threads, and JNI attaching threads  are skipped)
3851 // See CR 6404306 regarding JNI attaching threads
3852 JVM_ENTRY(jobjectArray, JVM_GetAllThreads(JNIEnv *env, jclass dummy))
3853   ResourceMark rm(THREAD);
3854   ThreadsListEnumerator tle(THREAD, false, false);
3855   JvmtiVMObjectAllocEventCollector oam;
3856 
3857   int num_threads = tle.num_threads();
3858   objArrayOop r = oopFactory::new_objArray(vmClasses::Thread_klass(), num_threads, CHECK_NULL);
3859   objArrayHandle threads_ah(THREAD, r);
3860 
3861   for (int i = 0; i < num_threads; i++) {
3862     Handle h = tle.get_threadObj(i);
3863     threads_ah->obj_at_put(i, h());
3864   }
3865 
3866   return (jobjectArray) JNIHandles::make_local(THREAD, threads_ah());
3867 JVM_END
3868 
3869 
3870 // Support for java.lang.Thread.getStackTrace() and getAllStackTraces() methods
3871 // Return StackTraceElement[][], each element is the stack trace of a thread in
3872 // the corresponding entry in the given threads array
3873 JVM_ENTRY(jobjectArray, JVM_DumpThreads(JNIEnv *env, jclass threadClass, jobjectArray threads))
3874   JvmtiVMObjectAllocEventCollector oam;
3875 
3876   // Check if threads is null
3877   if (threads == NULL) {
3878     THROW_(vmSymbols::java_lang_NullPointerException(), 0);
3879   }
3880 
3881   objArrayOop a = objArrayOop(JNIHandles::resolve_non_null(threads));
3882   objArrayHandle ah(THREAD, a);
3883   int num_threads = ah->length();
3884   // check if threads is non-empty array
3885   if (num_threads == 0) {
3886     THROW_(vmSymbols::java_lang_IllegalArgumentException(), 0);
3887   }
3888 
3889   // check if threads is not an array of objects of Thread class
3890   Klass* k = ObjArrayKlass::cast(ah->klass())->element_klass();
3891   if (k != vmClasses::Thread_klass()) {
3892     THROW_(vmSymbols::java_lang_IllegalArgumentException(), 0);
3893   }
3894 
3895   ResourceMark rm(THREAD);
3896 
3897   GrowableArray<instanceHandle>* thread_handle_array = new GrowableArray<instanceHandle>(num_threads);
3898   for (int i = 0; i < num_threads; i++) {
3899     oop thread_obj = ah->obj_at(i);
3900     instanceHandle h(THREAD, (instanceOop) thread_obj);
3901     thread_handle_array->append(h);
3902   }
3903 
3904   // The JavaThread references in thread_handle_array are validated
3905   // in VM_ThreadDump::doit().
3906   Handle stacktraces = ThreadService::dump_stack_traces(thread_handle_array, num_threads, CHECK_NULL);
3907   return (jobjectArray)JNIHandles::make_local(THREAD, stacktraces());
3908 
3909 JVM_END
3910 
3911 // JVM monitoring and management support
3912 JVM_LEAF(void*, JVM_GetManagement(jint version))
3913   return Management::get_jmm_interface(version);
3914 JVM_END
3915 
3916 // com.sun.tools.attach.VirtualMachine agent properties support
3917 //
3918 // Initialize the agent properties with the properties maintained in the VM
3919 JVM_ENTRY(jobject, JVM_InitAgentProperties(JNIEnv *env, jobject properties))
3920   ResourceMark rm;
3921 
3922   Handle props(THREAD, JNIHandles::resolve_non_null(properties));
3923 
3924   PUTPROP(props, "sun.java.command", Arguments::java_command());
3925   PUTPROP(props, "sun.jvm.flags", Arguments::jvm_flags());
3926   PUTPROP(props, "sun.jvm.args", Arguments::jvm_args());
3927   return properties;
3928 JVM_END
3929 
3930 JVM_ENTRY(jobjectArray, JVM_GetEnclosingMethodInfo(JNIEnv *env, jclass ofClass))
3931 {
3932   JvmtiVMObjectAllocEventCollector oam;
3933 
3934   if (ofClass == NULL) {
3935     return NULL;
3936   }
3937   Handle mirror(THREAD, JNIHandles::resolve_non_null(ofClass));
3938   // Special handling for primitive objects
3939   if (java_lang_Class::is_primitive(mirror())) {
3940     return NULL;
3941   }
3942   Klass* k = java_lang_Class::as_Klass(mirror());
3943   if (!k->is_instance_klass()) {
3944     return NULL;
3945   }
3946   InstanceKlass* ik = InstanceKlass::cast(k);
3947   int encl_method_class_idx = ik->enclosing_method_class_index();
3948   if (encl_method_class_idx == 0) {
3949     return NULL;
3950   }
3951   objArrayOop dest_o = oopFactory::new_objArray(vmClasses::Object_klass(), 3, CHECK_NULL);
3952   objArrayHandle dest(THREAD, dest_o);
3953   Klass* enc_k = ik->constants()->klass_at(encl_method_class_idx, CHECK_NULL);
3954   dest->obj_at_put(0, enc_k->java_mirror());
3955   int encl_method_method_idx = ik->enclosing_method_method_index();
3956   if (encl_method_method_idx != 0) {
3957     Symbol* sym = ik->constants()->symbol_at(
3958                         extract_low_short_from_int(
3959                           ik->constants()->name_and_type_at(encl_method_method_idx)));
3960     Handle str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
3961     dest->obj_at_put(1, str());
3962     sym = ik->constants()->symbol_at(
3963               extract_high_short_from_int(
3964                 ik->constants()->name_and_type_at(encl_method_method_idx)));
3965     str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
3966     dest->obj_at_put(2, str());
3967   }
3968   return (jobjectArray) JNIHandles::make_local(THREAD, dest());
3969 }
3970 JVM_END
3971 
3972 // Returns an array of java.lang.String objects containing the input arguments to the VM.
3973 JVM_ENTRY(jobjectArray, JVM_GetVmArguments(JNIEnv *env))
3974   ResourceMark rm(THREAD);
3975 
3976   if (Arguments::num_jvm_args() == 0 && Arguments::num_jvm_flags() == 0) {
3977     return NULL;
3978   }
3979 
3980   char** vm_flags = Arguments::jvm_flags_array();
3981   char** vm_args = Arguments::jvm_args_array();
3982   int num_flags = Arguments::num_jvm_flags();
3983   int num_args = Arguments::num_jvm_args();
3984 
3985   InstanceKlass* ik = vmClasses::String_klass();
3986   objArrayOop r = oopFactory::new_objArray(ik, num_args + num_flags, CHECK_NULL);
3987   objArrayHandle result_h(THREAD, r);
3988 
3989   int index = 0;
3990   for (int j = 0; j < num_flags; j++, index++) {
3991     Handle h = java_lang_String::create_from_platform_dependent_str(vm_flags[j], CHECK_NULL);
3992     result_h->obj_at_put(index, h());
3993   }
3994   for (int i = 0; i < num_args; i++, index++) {
3995     Handle h = java_lang_String::create_from_platform_dependent_str(vm_args[i], CHECK_NULL);
3996     result_h->obj_at_put(index, h());
3997   }
3998   return (jobjectArray) JNIHandles::make_local(THREAD, result_h());
3999 JVM_END
4000 
4001 JVM_LEAF(jint, JVM_FindSignal(const char *name))
4002   return os::get_signal_number(name);
4003 JVM_END
4004 
4005 JVM_ENTRY(void, JVM_VirtualThreadMountBegin(JNIEnv* env, jobject vthread, jboolean first_mount))
4006 #if INCLUDE_JVMTI
4007   if (!DoJVMTIVirtualThreadTransitions) {
4008     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
4009     return;
4010   }
4011   assert(!thread->is_in_tmp_VTMS_transition(), "sanity check");
4012   assert(!thread->is_in_VTMS_transition(), "sanity check");
4013   JvmtiVTMSTransitionDisabler::start_VTMS_transition(vthread, /* is_mount */ true);
4014 #else
4015   fatal("Should only be called with JVMTI enabled");
4016 #endif
4017 JVM_END
4018 
4019 JVM_ENTRY(void, JVM_VirtualThreadMountEnd(JNIEnv* env, jobject vthread, jboolean first_mount))
4020 #if INCLUDE_JVMTI
4021   if (!DoJVMTIVirtualThreadTransitions) {
4022     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
4023     return;
4024   }
4025   oop vt = JNIHandles::resolve(vthread);
4026 
4027   thread->rebind_to_jvmti_thread_state_of(vt);
4028 
4029   {
4030     MutexLocker mu(JvmtiThreadState_lock);
4031     JvmtiThreadState* state = thread->jvmti_thread_state();
4032     if (state != NULL && state->is_pending_interp_only_mode()) {
4033       JvmtiEventController::enter_interp_only_mode();
4034     }
4035   }
4036   assert(thread->is_in_VTMS_transition(), "sanity check");
4037   assert(!thread->is_in_tmp_VTMS_transition(), "sanity check");
4038   JvmtiVTMSTransitionDisabler::finish_VTMS_transition(vthread, /* is_mount */ true);
4039   if (first_mount) {
4040     // thread start
4041     if (JvmtiExport::can_support_virtual_threads()) {
4042       JvmtiEventController::thread_started(thread);
4043       if (JvmtiExport::should_post_vthread_start()) {
4044         JvmtiExport::post_vthread_start(vthread);
4045       }
4046     } else { // compatibility for vthread unaware agents: legacy thread_start
4047       if (PostVirtualThreadCompatibleLifecycleEvents &&
4048           JvmtiExport::should_post_thread_life()) {
4049         // JvmtiEventController::thread_started is called here
4050         JvmtiExport::post_thread_start(thread);
4051       }
4052     }
4053   }
4054   if (JvmtiExport::should_post_vthread_mount()) {
4055     JvmtiExport::post_vthread_mount(vthread);
4056   }
4057 #else
4058   fatal("Should only be called with JVMTI enabled");
4059 #endif
4060 JVM_END
4061 
4062 JVM_ENTRY(void, JVM_VirtualThreadUnmountBegin(JNIEnv* env, jobject vthread, jboolean last_unmount))
4063 #if INCLUDE_JVMTI
4064   if (!DoJVMTIVirtualThreadTransitions) {
4065     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
4066     return;
4067   }
4068   HandleMark hm(thread);
4069   Handle ct(thread, thread->threadObj());
4070 
4071   if (JvmtiExport::should_post_vthread_unmount()) {
4072     JvmtiExport::post_vthread_unmount(vthread);
4073   }
4074   if (last_unmount) {
4075     if (JvmtiExport::can_support_virtual_threads()) {
4076       if (JvmtiExport::should_post_vthread_end()) {
4077         JvmtiExport::post_vthread_end(vthread);
4078       }
4079     } else { // compatibility for vthread unaware agents: legacy thread_end
4080       if (PostVirtualThreadCompatibleLifecycleEvents &&
4081           JvmtiExport::should_post_thread_life()) {
4082         JvmtiExport::post_thread_end(thread);
4083       }
4084     }
4085   }
4086   assert(!thread->is_in_tmp_VTMS_transition(), "sanity check");
4087   assert(!thread->is_in_VTMS_transition(), "sanity check");
4088   JvmtiVTMSTransitionDisabler::start_VTMS_transition(vthread, /* is_mount */ false);
4089 
4090   if (last_unmount && thread->jvmti_thread_state() != NULL) {
4091     JvmtiExport::cleanup_thread(thread);
4092     thread->set_jvmti_thread_state(NULL);
4093     oop vt = JNIHandles::resolve(vthread);
4094     java_lang_Thread::set_jvmti_thread_state(vt, NULL);
4095   }
4096   thread->rebind_to_jvmti_thread_state_of(ct());
4097 #else
4098   fatal("Should only be called with JVMTI enabled");
4099 #endif
4100 JVM_END
4101 
4102 JVM_ENTRY(void, JVM_VirtualThreadUnmountEnd(JNIEnv* env, jobject vthread, jboolean last_unmount))
4103 #if INCLUDE_JVMTI
4104   if (!DoJVMTIVirtualThreadTransitions) {
4105     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
4106     return;
4107   }
4108   assert(thread->is_in_VTMS_transition(), "sanity check");
4109   assert(!thread->is_in_tmp_VTMS_transition(), "sanity check");
4110   JvmtiVTMSTransitionDisabler::finish_VTMS_transition(vthread, /* is_mount */ false);
4111 #else
4112   fatal("Should only be called with JVMTI enabled");
4113 #endif
4114 JVM_END
4115 
4116 JVM_ENTRY(void, JVM_VirtualThreadHideFrames(JNIEnv* env, jobject vthread, jboolean hide))
4117 #if INCLUDE_JVMTI
4118   if (!DoJVMTIVirtualThreadTransitions) {
4119     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
4120     return;
4121   }
4122   assert(!thread->is_in_VTMS_transition(), "sanity check");
4123   assert(thread->is_in_tmp_VTMS_transition() != (bool)hide, "sanity check");
4124   thread->toggle_is_in_tmp_VTMS_transition();
4125 #else
4126   fatal("Should only be called with JVMTI enabled");
4127 #endif
4128 JVM_END
4129 
4130 /*
4131  * Return the current class's class file version.  The low order 16 bits of the
4132  * returned jint contain the class's major version.  The high order 16 bits
4133  * contain the class's minor version.
4134  */
4135 JVM_ENTRY(jint, JVM_GetClassFileVersion(JNIEnv* env, jclass current))
4136   oop mirror = JNIHandles::resolve_non_null(current);
4137   if (java_lang_Class::is_primitive(mirror)) {
4138     // return latest major version and minor version of 0.
4139     return JVM_CLASSFILE_MAJOR_VERSION;
4140   }
4141   assert(!java_lang_Class::as_Klass(mirror)->is_array_klass(), "unexpected array class");
4142 
4143   Klass* c = java_lang_Class::as_Klass(mirror);
4144   assert(c->is_instance_klass(), "must be");
4145   InstanceKlass* ik = InstanceKlass::cast(c);
4146   return (ik->minor_version() << 16) | ik->major_version();
4147 JVM_END
4148 
4149 /*
4150  * Ensure that code doing a stackwalk and using javaVFrame::locals() to
4151  * get the value will see a materialized value and not a scalar-replaced
4152  * null value.
4153  */
4154 JVM_ENTRY(void, JVM_EnsureMaterializedForStackWalk_func(JNIEnv* env, jobject vthread, jobject value))
4155   JVM_EnsureMaterializedForStackWalk(env, value);
4156 JVM_END