1 /*
   2  * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "cds/aotClassInitializer.hpp"
  26 #include "cds/cdsConfig.hpp"
  27 #include "cds/classListParser.hpp"
  28 #include "cds/classListWriter.hpp"
  29 #include "cds/dynamicArchive.hpp"
  30 #include "cds/heapShared.hpp"
  31 #include "cds/lambdaFormInvokers.hpp"
  32 #include "cds/lambdaProxyClassDictionary.hpp"
  33 #include "classfile/classFileStream.hpp"
  34 #include "classfile/classLoader.inline.hpp"
  35 #include "classfile/classLoaderData.hpp"
  36 #include "classfile/classLoaderData.inline.hpp"
  37 #include "classfile/classLoadInfo.hpp"
  38 #include "classfile/javaAssertions.hpp"
  39 #include "classfile/javaClasses.inline.hpp"
  40 #include "classfile/moduleEntry.hpp"
  41 #include "classfile/modules.hpp"
  42 #include "classfile/packageEntry.hpp"
  43 #include "classfile/stringTable.hpp"
  44 #include "classfile/symbolTable.hpp"
  45 #include "classfile/systemDictionary.hpp"
  46 #include "classfile/vmClasses.hpp"
  47 #include "classfile/vmSymbols.hpp"
  48 #include "gc/shared/collectedHeap.inline.hpp"
  49 #include "interpreter/bytecode.hpp"
  50 #include "interpreter/bytecodeUtils.hpp"
  51 #include "jfr/jfrEvents.hpp"
  52 #include "jvm.h"
  53 #include "logging/log.hpp"
  54 #include "memory/oopFactory.hpp"
  55 #include "memory/referenceType.hpp"
  56 #include "memory/resourceArea.hpp"
  57 #include "memory/universe.hpp"
  58 #include "oops/access.inline.hpp"
  59 #include "oops/constantPool.hpp"
  60 #include "oops/fieldStreams.inline.hpp"
  61 #include "oops/flatArrayKlass.hpp"
  62 #include "oops/instanceKlass.hpp"
  63 #include "oops/klass.inline.hpp"
  64 #include "oops/method.hpp"
  65 #include "oops/recordComponent.hpp"
  66 #include "oops/objArrayKlass.hpp"
  67 #include "oops/objArrayOop.inline.hpp"
  68 #include "oops/oop.inline.hpp"
  69 #include "prims/foreignGlobals.hpp"
  70 #include "prims/jvm_misc.hpp"
  71 #include "prims/jvmtiExport.hpp"
  72 #include "prims/jvmtiThreadState.inline.hpp"
  73 #include "prims/stackwalk.hpp"
  74 #include "runtime/arguments.hpp"
  75 #include "runtime/atomic.hpp"
  76 #include "runtime/continuation.hpp"
  77 #include "runtime/globals_extension.hpp"
  78 #include "runtime/handles.inline.hpp"
  79 #include "runtime/init.hpp"
  80 #include "runtime/interfaceSupport.inline.hpp"
  81 #include "runtime/deoptimization.hpp"
  82 #include "runtime/handshake.hpp"
  83 #include "runtime/java.hpp"
  84 #include "runtime/javaCalls.hpp"
  85 #include "runtime/javaThread.hpp"
  86 #include "runtime/jfieldIDWorkaround.hpp"
  87 #include "runtime/jniHandles.inline.hpp"
  88 #include "runtime/os.inline.hpp"
  89 #include "runtime/osThread.hpp"
  90 #include "runtime/perfData.hpp"
  91 #include "runtime/reflection.hpp"
  92 #include "runtime/synchronizer.hpp"
  93 #include "runtime/threadIdentifier.hpp"
  94 #include "runtime/threadSMR.hpp"
  95 #include "runtime/vframe.inline.hpp"
  96 #include "runtime/vmOperations.hpp"
  97 #include "runtime/vm_version.hpp"
  98 #include "services/attachListener.hpp"
  99 #include "services/management.hpp"
 100 #include "services/threadService.hpp"
 101 #include "utilities/checkedCast.hpp"
 102 #include "utilities/copy.hpp"
 103 #include "utilities/defaultStream.hpp"
 104 #include "utilities/dtrace.hpp"
 105 #include "utilities/events.hpp"
 106 #include "utilities/macros.hpp"
 107 #include "utilities/utf8.hpp"
 108 #include "utilities/zipLibrary.hpp"
 109 #if INCLUDE_CDS
 110 #include "classfile/systemDictionaryShared.hpp"
 111 #endif
 112 #if INCLUDE_JFR
 113 #include "jfr/jfr.hpp"
 114 #endif
 115 #if INCLUDE_MANAGEMENT
 116 #include "services/finalizerService.hpp"
 117 #endif
 118 #ifdef LINUX
 119 #include "osContainer_linux.hpp"
 120 #endif
 121 
 122 #include <errno.h>
 123 
 124 /*
 125   NOTE about use of any ctor or function call that can trigger a safepoint/GC:
 126   such ctors and calls MUST NOT come between an oop declaration/init and its
 127   usage because if objects are move this may cause various memory stomps, bus
 128   errors and segfaults. Here is a cookbook for causing so called "naked oop
 129   failures":
 130 
 131       JVM_ENTRY(jobjectArray, JVM_GetClassDeclaredFields<etc> {
 132           // Object address to be held directly in mirror & not visible to GC
 133           oop mirror = JNIHandles::resolve_non_null(ofClass);
 134 
 135           // If this ctor can hit a safepoint, moving objects around, then
 136           ComplexConstructor foo;
 137 
 138           // Boom! mirror may point to JUNK instead of the intended object
 139           (some dereference of mirror)
 140 
 141           // Here's another call that may block for GC, making mirror stale
 142           MutexLocker ml(some_lock);
 143 
 144           // And here's an initializer that can result in a stale oop
 145           // all in one step.
 146           oop o = call_that_can_throw_exception(TRAPS);
 147 
 148 
 149   The solution is to keep the oop declaration BELOW the ctor or function
 150   call that might cause a GC, do another resolve to reassign the oop, or
 151   consider use of a Handle instead of an oop so there is immunity from object
 152   motion. But note that the "QUICK" entries below do not have a handlemark
 153   and thus can only support use of handles passed in.
 154 */
 155 
 156 extern void trace_class_resolution(Klass* to_class) {
 157   ResourceMark rm;
 158   int line_number = -1;
 159   const char * source_file = nullptr;
 160   const char * trace = "explicit";
 161   InstanceKlass* caller = nullptr;
 162   JavaThread* jthread = JavaThread::current();
 163   if (jthread->has_last_Java_frame()) {
 164     vframeStream vfst(jthread);
 165 
 166     // Scan up the stack skipping ClassLoader frames.
 167     Method* last_caller = nullptr;
 168 
 169     while (!vfst.at_end()) {
 170       Method* m = vfst.method();
 171       if (!vfst.method()->method_holder()->is_subclass_of(vmClasses::ClassLoader_klass())) {
 172         break;
 173       }
 174       last_caller = m;
 175       vfst.next();
 176     }
 177     // if this is called from Class.forName0 and that is called from Class.forName,
 178     // then print the caller of Class.forName.  If this is Class.loadClass, then print
 179     // that caller, otherwise keep quiet since this should be picked up elsewhere.
 180     bool found_it = false;
 181     if (!vfst.at_end() &&
 182         vfst.method()->method_holder()->name() == vmSymbols::java_lang_Class() &&
 183         vfst.method()->name() == vmSymbols::forName0_name()) {
 184       vfst.next();
 185       if (!vfst.at_end() &&
 186           vfst.method()->method_holder()->name() == vmSymbols::java_lang_Class() &&
 187           vfst.method()->name() == vmSymbols::forName_name()) {
 188         vfst.next();
 189         found_it = true;
 190       }
 191     } else if (last_caller != nullptr &&
 192                last_caller->method_holder()->name() ==
 193                  vmSymbols::java_lang_ClassLoader() &&
 194                last_caller->name() == vmSymbols::loadClass_name()) {
 195       found_it = true;
 196     } else if (!vfst.at_end()) {
 197       if (vfst.method()->is_native()) {
 198         // JNI call
 199         found_it = true;
 200       }
 201     }
 202     if (found_it && !vfst.at_end()) {
 203       // found the caller
 204       caller = vfst.method()->method_holder();
 205       line_number = vfst.method()->line_number_from_bci(vfst.bci());
 206       if (line_number == -1) {
 207         // show method name if it's a native method
 208         trace = vfst.method()->name_and_sig_as_C_string();
 209       }
 210       Symbol* s = caller->source_file_name();
 211       if (s != nullptr) {
 212         source_file = s->as_C_string();
 213       }
 214     }
 215   }
 216   if (caller != nullptr) {
 217     if (to_class != caller) {
 218       const char * from = caller->external_name();
 219       const char * to = to_class->external_name();
 220       // print in a single call to reduce interleaving between threads
 221       if (source_file != nullptr) {
 222         log_debug(class, resolve)("%s %s %s:%d (%s)", from, to, source_file, line_number, trace);
 223       } else {
 224         log_debug(class, resolve)("%s %s (%s)", from, to, trace);
 225       }
 226     }
 227   }
 228 }
 229 
 230 // java.lang.System //////////////////////////////////////////////////////////////////////
 231 
 232 
 233 JVM_LEAF(jlong, JVM_CurrentTimeMillis(JNIEnv *env, jclass ignored))
 234   return os::javaTimeMillis();
 235 JVM_END
 236 
 237 JVM_LEAF(jlong, JVM_NanoTime(JNIEnv *env, jclass ignored))
 238   return os::javaTimeNanos();
 239 JVM_END
 240 
 241 // The function below is actually exposed by jdk.internal.misc.VM and not
 242 // java.lang.System, but we choose to keep it here so that it stays next
 243 // to JVM_CurrentTimeMillis and JVM_NanoTime
 244 
 245 const jlong MAX_DIFF_SECS = CONST64(0x0100000000); //  2^32
 246 const jlong MIN_DIFF_SECS = -MAX_DIFF_SECS; // -2^32
 247 
 248 JVM_LEAF(jlong, JVM_GetNanoTimeAdjustment(JNIEnv *env, jclass ignored, jlong offset_secs))
 249   jlong seconds;
 250   jlong nanos;
 251 
 252   os::javaTimeSystemUTC(seconds, nanos);
 253 
 254   // We're going to verify that the result can fit in a long.
 255   // For that we need the difference in seconds between 'seconds'
 256   // and 'offset_secs' to be such that:
 257   //     |seconds - offset_secs| < (2^63/10^9)
 258   // We're going to approximate 10^9 ~< 2^30 (1000^3 ~< 1024^3)
 259   // which makes |seconds - offset_secs| < 2^33
 260   // and we will prefer +/- 2^32 as the maximum acceptable diff
 261   // as 2^32 has a more natural feel than 2^33...
 262   //
 263   // So if |seconds - offset_secs| >= 2^32 - we return a special
 264   // sentinel value (-1) which the caller should take as an
 265   // exception value indicating that the offset given to us is
 266   // too far from range of the current time - leading to too big
 267   // a nano adjustment. The caller is expected to recover by
 268   // computing a more accurate offset and calling this method
 269   // again. (For the record 2^32 secs is ~136 years, so that
 270   // should rarely happen)
 271   //
 272   jlong diff = seconds - offset_secs;
 273   if (diff >= MAX_DIFF_SECS || diff <= MIN_DIFF_SECS) {
 274      return -1; // sentinel value: the offset is too far off the target
 275   }
 276 
 277   // return the adjustment. If you compute a time by adding
 278   // this number of nanoseconds along with the number of seconds
 279   // in the offset you should get the current UTC time.
 280   return (diff * (jlong)1000000000) + nanos;
 281 JVM_END
 282 
 283 JVM_ENTRY(void, JVM_ArrayCopy(JNIEnv *env, jclass ignored, jobject src, jint src_pos,
 284                                jobject dst, jint dst_pos, jint length))
 285   // Check if we have null pointers
 286   if (src == nullptr || dst == nullptr) {
 287     THROW(vmSymbols::java_lang_NullPointerException());
 288   }
 289   arrayOop s = arrayOop(JNIHandles::resolve_non_null(src));
 290   arrayOop d = arrayOop(JNIHandles::resolve_non_null(dst));
 291   assert(oopDesc::is_oop(s), "JVM_ArrayCopy: src not an oop");
 292   assert(oopDesc::is_oop(d), "JVM_ArrayCopy: dst not an oop");
 293   // Do copy
 294   s->klass()->copy_array(s, src_pos, d, dst_pos, length, thread);
 295 JVM_END
 296 
 297 
 298 static void set_property(Handle props, const char* key, const char* value, TRAPS) {
 299   JavaValue r(T_OBJECT);
 300   // public synchronized Object put(Object key, Object value);
 301   HandleMark hm(THREAD);
 302   Handle key_str    = java_lang_String::create_from_platform_dependent_str(key, CHECK);
 303   Handle value_str  = java_lang_String::create_from_platform_dependent_str((value != nullptr ? value : ""), CHECK);
 304   JavaCalls::call_virtual(&r,
 305                           props,
 306                           vmClasses::Properties_klass(),
 307                           vmSymbols::put_name(),
 308                           vmSymbols::object_object_object_signature(),
 309                           key_str,
 310                           value_str,
 311                           THREAD);
 312 }
 313 
 314 
 315 #define PUTPROP(props, name, value) set_property((props), (name), (value), CHECK_(properties));
 316 
 317 /*
 318  * Return all of the system properties in a Java String array with alternating
 319  * names and values from the jvm SystemProperty.
 320  * Which includes some internal and all commandline -D defined properties.
 321  */
 322 JVM_ENTRY(jobjectArray, JVM_GetProperties(JNIEnv *env))
 323   ResourceMark rm(THREAD);
 324   HandleMark hm(THREAD);
 325   int ndx = 0;
 326   int fixedCount = 2;
 327 
 328   SystemProperty* p = Arguments::system_properties();
 329   int count = Arguments::PropertyList_count(p);
 330 
 331   // Allocate result String array
 332   InstanceKlass* ik = vmClasses::String_klass();
 333   objArrayOop r = oopFactory::new_objArray(ik, (count + fixedCount) * 2, CHECK_NULL);
 334   objArrayHandle result_h(THREAD, r);
 335 
 336   while (p != nullptr) {
 337     const char * key = p->key();
 338     if (strcmp(key, "sun.nio.MaxDirectMemorySize") != 0) {
 339         const char * value = p->value();
 340         Handle key_str    = java_lang_String::create_from_platform_dependent_str(key, CHECK_NULL);
 341         Handle value_str  = java_lang_String::create_from_platform_dependent_str((value != nullptr ? value : ""), CHECK_NULL);
 342         result_h->obj_at_put(ndx * 2,  key_str());
 343         result_h->obj_at_put(ndx * 2 + 1, value_str());
 344         ndx++;
 345     }
 346     p = p->next();
 347   }
 348 
 349   // Convert the -XX:MaxDirectMemorySize= command line flag
 350   // to the sun.nio.MaxDirectMemorySize property.
 351   // Do this after setting user properties to prevent people
 352   // from setting the value with a -D option, as requested.
 353   // Leave empty if not supplied
 354   if (!FLAG_IS_DEFAULT(MaxDirectMemorySize)) {
 355     char as_chars[256];
 356     jio_snprintf(as_chars, sizeof(as_chars), JULONG_FORMAT, MaxDirectMemorySize);
 357     Handle key_str = java_lang_String::create_from_platform_dependent_str("sun.nio.MaxDirectMemorySize", CHECK_NULL);
 358     Handle value_str  = java_lang_String::create_from_platform_dependent_str(as_chars, CHECK_NULL);
 359     result_h->obj_at_put(ndx * 2,  key_str());
 360     result_h->obj_at_put(ndx * 2 + 1, value_str());
 361     ndx++;
 362   }
 363 
 364   // JVM monitoring and management support
 365   // Add the sun.management.compiler property for the compiler's name
 366   {
 367 #undef CSIZE
 368 #if defined(_LP64)
 369   #define CSIZE "64-Bit "
 370 #else
 371   #define CSIZE
 372 #endif // 64bit
 373 
 374 #if COMPILER1_AND_COMPILER2
 375     const char* compiler_name = "HotSpot " CSIZE "Tiered Compilers";
 376 #else
 377 #if defined(COMPILER1)
 378     const char* compiler_name = "HotSpot " CSIZE "Client Compiler";
 379 #elif defined(COMPILER2)
 380     const char* compiler_name = "HotSpot " CSIZE "Server Compiler";
 381 #elif INCLUDE_JVMCI
 382     #error "INCLUDE_JVMCI should imply COMPILER1_OR_COMPILER2"
 383 #else
 384     const char* compiler_name = "";
 385 #endif // compilers
 386 #endif // COMPILER1_AND_COMPILER2
 387 
 388     if (*compiler_name != '\0' &&
 389         (Arguments::mode() != Arguments::_int)) {
 390       Handle key_str = java_lang_String::create_from_platform_dependent_str("sun.management.compiler", CHECK_NULL);
 391       Handle value_str  = java_lang_String::create_from_platform_dependent_str(compiler_name, CHECK_NULL);
 392       result_h->obj_at_put(ndx * 2,  key_str());
 393       result_h->obj_at_put(ndx * 2 + 1, value_str());
 394       ndx++;
 395     }
 396   }
 397 
 398   return (jobjectArray) JNIHandles::make_local(THREAD, result_h());
 399 JVM_END
 400 
 401 
 402 /*
 403  * Return the temporary directory that the VM uses for the attach
 404  * and perf data files.
 405  *
 406  * It is important that this directory is well-known and the
 407  * same for all VM instances. It cannot be affected by configuration
 408  * variables such as java.io.tmpdir.
 409  */
 410 JVM_ENTRY(jstring, JVM_GetTemporaryDirectory(JNIEnv *env))
 411   HandleMark hm(THREAD);
 412   const char* temp_dir = os::get_temp_directory();
 413   Handle h = java_lang_String::create_from_platform_dependent_str(temp_dir, CHECK_NULL);
 414   return (jstring) JNIHandles::make_local(THREAD, h());
 415 JVM_END
 416 
 417 static void validate_array_arguments(Klass* elmClass, jint len, TRAPS) {
 418   if (len < 0) {
 419     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "Array length is negative");
 420   }
 421   elmClass->initialize(CHECK);
 422   if (elmClass->is_array_klass() || elmClass->is_identity_class()) {
 423     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "Element class is not a value class");
 424   }
 425   if (elmClass->is_abstract()) {
 426     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "Element class is abstract");
 427   }
 428 }
 429 
 430 JVM_ENTRY(jarray, JVM_CopyOfSpecialArray(JNIEnv *env, jarray orig, jint from, jint to))
 431   oop o = JNIHandles::resolve_non_null(orig);
 432   assert(o->is_array(), "Must be");
 433   oop array = nullptr;
 434   arrayOop org = (arrayOop)o;
 435   arrayHandle oh(THREAD, org);
 436   ArrayKlass* ak = ArrayKlass::cast(org->klass());
 437   InlineKlass* vk = InlineKlass::cast(ak->element_klass());
 438   int len = to - from;  // length of the new array
 439   if (ak->is_null_free_array_klass()) {
 440     if (from >= org->length() || to > org->length()) {
 441       THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Copying of null-free array with uninitialized elements");
 442     }
 443   }
 444   if (org->is_flatArray()) {
 445     FlatArrayKlass* fak = FlatArrayKlass::cast(org->klass());
 446     LayoutKind lk = fak->layout_kind();
 447     array = oopFactory::new_flatArray(vk, len, lk, CHECK_NULL);
 448     arrayHandle ah(THREAD, (arrayOop)array);
 449     int end = to < oh()->length() ? to : oh()->length();
 450     for (int i = from; i < end; i++) {
 451       void* src = ((flatArrayOop)oh())->value_at_addr(i, fak->layout_helper());
 452       void* dst = ((flatArrayOop)ah())->value_at_addr(i - from, fak->layout_helper());
 453       vk->copy_payload_to_addr(src, dst, lk, false);
 454     }
 455     array = ah();
 456   } else {
 457     if (org->is_null_free_array()) {
 458       array = oopFactory::new_null_free_objArray(vk, len, CHECK_NULL);
 459     } else {
 460       array = oopFactory::new_objArray(vk, len, CHECK_NULL);
 461     }
 462     int end = to < oh()->length() ? to : oh()->length();
 463     for (int i = from; i < end; i++) {
 464       if (i < ((objArrayOop)oh())->length()) {
 465         ((objArrayOop)array)->obj_at_put(i - from, ((objArrayOop)oh())->obj_at(i));
 466       } else {
 467         assert(!ak->is_null_free_array_klass(), "Must be a nullable array");
 468         ((objArrayOop)array)->obj_at_put(i - from, nullptr);
 469       }
 470     }
 471   }
 472   return (jarray) JNIHandles::make_local(THREAD, array);
 473 JVM_END
 474 
 475 JVM_ENTRY(jarray, JVM_NewNullRestrictedNonAtomicArray(JNIEnv *env, jclass elmClass, jint len, jobject initVal))
 476   oop mirror = JNIHandles::resolve_non_null(elmClass);
 477   oop init = JNIHandles::resolve(initVal);
 478   if (init == nullptr) {
 479     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Initial value cannot be null");
 480   }
 481   Handle init_h(THREAD, init);
 482   Klass* klass = java_lang_Class::as_Klass(mirror);
 483   if (klass != init_h()->klass()) {
 484     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Type mismatch between array and initial value");
 485   }
 486   validate_array_arguments(klass, len, CHECK_NULL);
 487   InlineKlass* vk = InlineKlass::cast(klass);
 488   oop array = nullptr;
 489   if (vk->maybe_flat_in_array() && vk->has_non_atomic_layout()) {
 490     array = oopFactory::new_flatArray(vk, len, LayoutKind::NON_ATOMIC_FLAT, CHECK_NULL);
 491     for (int i = 0; i < len; i++) {
 492       ((flatArrayOop)array)->write_value_to_flat_array(init_h(), i, CHECK_NULL);
 493     }
 494   } else {
 495     array = oopFactory::new_null_free_objArray(vk, len, CHECK_NULL);
 496     for (int i = 0; i < len; i++) {
 497       ((objArrayOop)array)->obj_at_put(i, init_h());
 498     }
 499   }
 500   return (jarray) JNIHandles::make_local(THREAD, array);
 501 JVM_END
 502 
 503 JVM_ENTRY(jarray, JVM_NewNullRestrictedAtomicArray(JNIEnv *env, jclass elmClass, jint len, jobject initVal))
 504   oop mirror = JNIHandles::resolve_non_null(elmClass);
 505   oop init = JNIHandles::resolve(initVal);
 506   if (init == nullptr) {
 507     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Initial value cannot be null");
 508   }
 509   Handle init_h(THREAD, init);
 510   Klass* klass = java_lang_Class::as_Klass(mirror);
 511   if (klass != init_h()->klass()) {
 512     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Type mismatch between array and initial value");
 513   }
 514   validate_array_arguments(klass, len, CHECK_NULL);
 515   InlineKlass* vk = InlineKlass::cast(klass);
 516   oop array = nullptr;
 517   if (vk->maybe_flat_in_array() && vk->is_naturally_atomic() && vk->has_non_atomic_layout()) {
 518     array = oopFactory::new_flatArray(vk, len, LayoutKind::NON_ATOMIC_FLAT, CHECK_NULL);
 519     for (int i = 0; i < len; i++) {
 520       ((flatArrayOop)array)->write_value_to_flat_array(init_h(), i, CHECK_NULL);
 521     }
 522   } else if (vk->maybe_flat_in_array() && vk->has_atomic_layout()) {
 523     array = oopFactory::new_flatArray(vk, len, LayoutKind::ATOMIC_FLAT, CHECK_NULL);
 524     for (int i = 0; i < len; i++) {
 525       ((flatArrayOop)array)->write_value_to_flat_array(init_h(), i, CHECK_NULL);
 526     }
 527   } else {
 528     array = oopFactory::new_null_free_objArray(vk, len, CHECK_NULL);
 529     for (int i = 0; i < len; i++) {
 530       // need a type check here
 531 
 532       ((objArrayOop)array)->obj_at_put(i, init_h());
 533     }
 534   }
 535   return (jarray) JNIHandles::make_local(THREAD, array);
 536 JVM_END
 537 
 538 JVM_ENTRY(jarray, JVM_NewNullableAtomicArray(JNIEnv *env, jclass elmClass, jint len))
 539   oop mirror = JNIHandles::resolve_non_null(elmClass);
 540   Klass* klass = java_lang_Class::as_Klass(mirror);
 541   klass->initialize(CHECK_NULL);
 542   validate_array_arguments(klass, len, CHECK_NULL);
 543   InlineKlass* vk = InlineKlass::cast(klass);
 544   oop array = nullptr;
 545   if (vk->maybe_flat_in_array() && vk->has_nullable_atomic_layout()) {
 546     array = oopFactory::new_flatArray(vk, len, LayoutKind::NULLABLE_ATOMIC_FLAT, CHECK_NULL);
 547   } else {
 548     array = oopFactory::new_objArray(vk, len, CHECK_NULL);
 549   }
 550   return (jarray) JNIHandles::make_local(THREAD, array);
 551 JVM_END
 552 
 553 JVM_ENTRY(jboolean, JVM_IsFlatArray(JNIEnv *env, jobject obj))
 554   arrayOop oop = arrayOop(JNIHandles::resolve_non_null(obj));
 555   return oop->is_flatArray();
 556 JVM_END
 557 
 558 JVM_ENTRY(jboolean, JVM_IsNullRestrictedArray(JNIEnv *env, jobject obj))
 559   arrayOop oop = arrayOop(JNIHandles::resolve_non_null(obj));
 560   return oop->is_null_free_array();
 561 JVM_END
 562 
 563 JVM_ENTRY(jboolean, JVM_IsAtomicArray(JNIEnv *env, jobject obj))
 564   // There are multiple cases where an array can/must support atomic access:
 565   //   - the array is a reference array
 566   //   - the array uses an atomic flat layout: NULLABLE_ATOMIC_FLAT or ATOMIC_FLAT
 567   //   - the array is flat and its component type is naturally atomic
 568   arrayOop oop = arrayOop(JNIHandles::resolve_non_null(obj));
 569   if (oop->is_objArray()) return true;
 570   if (oop->is_flatArray()) {
 571     FlatArrayKlass* fak = FlatArrayKlass::cast(oop->klass());
 572     if (fak->layout_kind() == LayoutKind::ATOMIC_FLAT || fak->layout_kind() == LayoutKind::NULLABLE_ATOMIC_FLAT) {
 573       return true;
 574     }
 575     if (fak->element_klass()->is_naturally_atomic()) return true;
 576   }
 577   return false;
 578 JVM_END
 579 
 580 // java.lang.Runtime /////////////////////////////////////////////////////////////////////////
 581 
 582 extern volatile jint vm_created;
 583 
 584 JVM_ENTRY_NO_ENV(void, JVM_BeforeHalt())
 585   EventShutdown event;
 586   if (event.should_commit()) {
 587     event.set_reason("Shutdown requested from Java");
 588     event.commit();
 589   }
 590 JVM_END
 591 
 592 
 593 JVM_ENTRY_NO_ENV(void, JVM_Halt(jint code))
 594   before_exit(thread, true);
 595   vm_exit(code);
 596 JVM_END
 597 
 598 
 599 JVM_ENTRY_NO_ENV(void, JVM_GC(void))
 600   if (!DisableExplicitGC) {
 601     EventSystemGC event;
 602     event.set_invokedConcurrent(ExplicitGCInvokesConcurrent);
 603     Universe::heap()->collect(GCCause::_java_lang_system_gc);
 604     event.commit();
 605   }
 606 JVM_END
 607 
 608 
 609 JVM_LEAF(jlong, JVM_MaxObjectInspectionAge(void))
 610   return Universe::heap()->millis_since_last_whole_heap_examined();
 611 JVM_END
 612 
 613 
 614 static inline jlong convert_size_t_to_jlong(size_t val) {
 615   // In the 64-bit vm, a size_t can overflow a jlong (which is signed).
 616   NOT_LP64 (return (jlong)val;)
 617   LP64_ONLY(return (jlong)MIN2(val, (size_t)max_jlong);)
 618 }
 619 
 620 JVM_ENTRY_NO_ENV(jlong, JVM_TotalMemory(void))
 621   size_t n = Universe::heap()->capacity();
 622   return convert_size_t_to_jlong(n);
 623 JVM_END
 624 
 625 
 626 JVM_ENTRY_NO_ENV(jlong, JVM_FreeMemory(void))
 627   size_t n = Universe::heap()->unused();
 628   return convert_size_t_to_jlong(n);
 629 JVM_END
 630 
 631 
 632 JVM_ENTRY_NO_ENV(jlong, JVM_MaxMemory(void))
 633   size_t n = Universe::heap()->max_capacity();
 634   return convert_size_t_to_jlong(n);
 635 JVM_END
 636 
 637 
 638 JVM_ENTRY_NO_ENV(jint, JVM_ActiveProcessorCount(void))
 639   return os::active_processor_count();
 640 JVM_END
 641 
 642 JVM_LEAF(jboolean, JVM_IsUseContainerSupport(void))
 643 #ifdef LINUX
 644   if (UseContainerSupport) {
 645     return JNI_TRUE;
 646   }
 647 #endif
 648   return JNI_FALSE;
 649 JVM_END
 650 
 651 JVM_LEAF(jboolean, JVM_IsContainerized(void))
 652 #ifdef LINUX
 653   if (OSContainer::is_containerized()) {
 654     return JNI_TRUE;
 655   }
 656 #endif
 657   return JNI_FALSE;
 658 JVM_END
 659 
 660 // java.lang.Throwable //////////////////////////////////////////////////////
 661 
 662 JVM_ENTRY(void, JVM_FillInStackTrace(JNIEnv *env, jobject receiver))
 663   Handle exception(thread, JNIHandles::resolve_non_null(receiver));
 664   java_lang_Throwable::fill_in_stack_trace(exception);
 665 JVM_END
 666 
 667 // java.lang.NullPointerException ///////////////////////////////////////////
 668 
 669 JVM_ENTRY(jstring, JVM_GetExtendedNPEMessage(JNIEnv *env, jthrowable throwable))
 670   if (!ShowCodeDetailsInExceptionMessages) return nullptr;
 671 
 672   oop exc = JNIHandles::resolve_non_null(throwable);
 673 
 674   Method* method;
 675   int bci;
 676   if (!java_lang_Throwable::get_top_method_and_bci(exc, &method, &bci)) {
 677     return nullptr;
 678   }
 679   if (method->is_native()) {
 680     return nullptr;
 681   }
 682 
 683   stringStream ss;
 684   bool ok = BytecodeUtils::get_NPE_message_at(&ss, method, bci);
 685   if (ok) {
 686     oop result = java_lang_String::create_oop_from_str(ss.base(), CHECK_NULL);
 687     return (jstring) JNIHandles::make_local(THREAD, result);
 688   } else {
 689     return nullptr;
 690   }
 691 JVM_END
 692 
 693 // java.lang.StackTraceElement //////////////////////////////////////////////
 694 
 695 
 696 JVM_ENTRY(void, JVM_InitStackTraceElementArray(JNIEnv *env, jobjectArray elements, jobject backtrace, jint depth))
 697   Handle backtraceh(THREAD, JNIHandles::resolve(backtrace));
 698   objArrayOop st = objArrayOop(JNIHandles::resolve(elements));
 699   objArrayHandle stack_trace(THREAD, st);
 700   // Fill in the allocated stack trace
 701   java_lang_Throwable::get_stack_trace_elements(depth, backtraceh, stack_trace, CHECK);
 702 JVM_END
 703 
 704 
 705 JVM_ENTRY(void, JVM_InitStackTraceElement(JNIEnv* env, jobject element, jobject stackFrameInfo))
 706   Handle stack_frame_info(THREAD, JNIHandles::resolve_non_null(stackFrameInfo));
 707   Handle stack_trace_element(THREAD, JNIHandles::resolve_non_null(element));
 708   java_lang_StackFrameInfo::to_stack_trace_element(stack_frame_info, stack_trace_element, CHECK);
 709 JVM_END
 710 
 711 
 712 // java.lang.StackWalker //////////////////////////////////////////////////////
 713 JVM_ENTRY(void, JVM_ExpandStackFrameInfo(JNIEnv *env, jobject obj))
 714   Handle stack_frame_info(THREAD, JNIHandles::resolve_non_null(obj));
 715 
 716   bool have_name = (java_lang_StackFrameInfo::name(stack_frame_info()) != nullptr);
 717   bool have_type = (java_lang_StackFrameInfo::type(stack_frame_info()) != nullptr);
 718   Method* method = java_lang_StackFrameInfo::get_method(stack_frame_info());
 719   if (!have_name) {
 720     oop name = StringTable::intern(method->name(), CHECK);
 721     java_lang_StackFrameInfo::set_name(stack_frame_info(), name);
 722   }
 723   if (!have_type) {
 724     Handle type = java_lang_String::create_from_symbol(method->signature(), CHECK);
 725     java_lang_StackFrameInfo::set_type(stack_frame_info(), type());
 726   }
 727 JVM_END
 728 
 729 JVM_ENTRY(jobject, JVM_CallStackWalk(JNIEnv *env, jobject stackStream, jint mode,
 730                                      jint skip_frames, jobject contScope, jobject cont,
 731                                      jint buffer_size, jint start_index, jobjectArray frames))
 732   if (!thread->has_last_Java_frame()) {
 733     THROW_MSG_(vmSymbols::java_lang_InternalError(), "doStackWalk: no stack trace", nullptr);
 734   }
 735 
 736   Handle stackStream_h(THREAD, JNIHandles::resolve_non_null(stackStream));
 737   Handle contScope_h(THREAD, JNIHandles::resolve(contScope));
 738   Handle cont_h(THREAD, JNIHandles::resolve(cont));
 739   // frames array is a ClassFrameInfo[] array when only getting caller reference,
 740   // and a StackFrameInfo[] array (or derivative) otherwise. It should never
 741   // be null.
 742   objArrayOop fa = objArrayOop(JNIHandles::resolve_non_null(frames));
 743   objArrayHandle frames_array_h(THREAD, fa);
 744 
 745   if (frames_array_h->length() < buffer_size) {
 746     THROW_MSG_(vmSymbols::java_lang_IllegalArgumentException(), "not enough space in buffers", nullptr);
 747   }
 748 
 749   oop result = StackWalk::walk(stackStream_h, mode, skip_frames, contScope_h, cont_h,
 750                                buffer_size, start_index, frames_array_h, CHECK_NULL);
 751   return JNIHandles::make_local(THREAD, result);
 752 JVM_END
 753 
 754 
 755 JVM_ENTRY(jint, JVM_MoreStackWalk(JNIEnv *env, jobject stackStream, jint mode, jlong anchor,
 756                                   jint last_batch_count, jint buffer_size, jint start_index,
 757                                   jobjectArray frames))
 758   // frames array is a ClassFrameInfo[] array when only getting caller reference,
 759   // and a StackFrameInfo[] array (or derivative) otherwise. It should never
 760   // be null.
 761   objArrayOop fa = objArrayOop(JNIHandles::resolve_non_null(frames));
 762   objArrayHandle frames_array_h(THREAD, fa);
 763 
 764   if (frames_array_h->length() < buffer_size) {
 765     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "not enough space in buffers");
 766   }
 767 
 768   Handle stackStream_h(THREAD, JNIHandles::resolve_non_null(stackStream));
 769   return StackWalk::fetchNextBatch(stackStream_h, mode, anchor, last_batch_count, buffer_size,
 770                                   start_index, frames_array_h, THREAD);
 771 JVM_END
 772 
 773 JVM_ENTRY(void, JVM_SetStackWalkContinuation(JNIEnv *env, jobject stackStream, jlong anchor, jobjectArray frames, jobject cont))
 774   objArrayOop fa = objArrayOop(JNIHandles::resolve_non_null(frames));
 775   objArrayHandle frames_array_h(THREAD, fa);
 776   Handle stackStream_h(THREAD, JNIHandles::resolve_non_null(stackStream));
 777   Handle cont_h(THREAD, JNIHandles::resolve_non_null(cont));
 778 
 779   StackWalk::setContinuation(stackStream_h, anchor, frames_array_h, cont_h, THREAD);
 780 JVM_END
 781 
 782 // java.lang.Object ///////////////////////////////////////////////
 783 
 784 
 785 JVM_ENTRY(jint, JVM_IHashCode(JNIEnv* env, jobject handle))
 786   // as implemented in the classic virtual machine; return 0 if object is null
 787   if (handle == nullptr) {
 788     return 0;
 789   }
 790   oop obj = JNIHandles::resolve_non_null(handle);
 791   if (EnableValhalla && obj->klass()->is_inline_klass()) {
 792       JavaValue result(T_INT);
 793       JavaCallArguments args;
 794       Handle ho(THREAD, obj);
 795       args.push_oop(ho);
 796       methodHandle method(THREAD, Universe::value_object_hash_code_method());
 797       JavaCalls::call(&result, method, &args, THREAD);
 798       if (HAS_PENDING_EXCEPTION) {
 799         if (!PENDING_EXCEPTION->is_a(vmClasses::Error_klass())) {
 800           Handle e(THREAD, PENDING_EXCEPTION);
 801           CLEAR_PENDING_EXCEPTION;
 802           THROW_MSG_CAUSE_(vmSymbols::java_lang_InternalError(), "Internal error in hashCode", e, false);
 803         }
 804       }
 805       return result.get_jint();
 806   } else {
 807     return checked_cast<jint>(ObjectSynchronizer::FastHashCode(THREAD, obj));
 808   }
 809 JVM_END
 810 
 811 
 812 JVM_ENTRY(void, JVM_MonitorWait(JNIEnv* env, jobject handle, jlong ms))
 813   Handle obj(THREAD, JNIHandles::resolve_non_null(handle));
 814   ObjectSynchronizer::wait(obj, ms, CHECK);
 815 JVM_END
 816 
 817 
 818 JVM_ENTRY(void, JVM_MonitorNotify(JNIEnv* env, jobject handle))
 819   Handle obj(THREAD, JNIHandles::resolve_non_null(handle));
 820   ObjectSynchronizer::notify(obj, CHECK);
 821 JVM_END
 822 
 823 
 824 JVM_ENTRY(void, JVM_MonitorNotifyAll(JNIEnv* env, jobject handle))
 825   Handle obj(THREAD, JNIHandles::resolve_non_null(handle));
 826   ObjectSynchronizer::notifyall(obj, CHECK);
 827 JVM_END
 828 
 829 
 830 JVM_ENTRY(jobject, JVM_Clone(JNIEnv* env, jobject handle))
 831   Handle obj(THREAD, JNIHandles::resolve_non_null(handle));
 832   Klass* klass = obj->klass();
 833   JvmtiVMObjectAllocEventCollector oam;
 834 
 835 #ifdef ASSERT
 836   // Just checking that the cloneable flag is set correct
 837   if (obj->is_array()) {
 838     guarantee(klass->is_cloneable(), "all arrays are cloneable");
 839   } else {
 840     guarantee(obj->is_instance(), "should be instanceOop");
 841     bool cloneable = klass->is_subtype_of(vmClasses::Cloneable_klass());
 842     guarantee(cloneable == klass->is_cloneable(), "incorrect cloneable flag");
 843   }
 844 #endif
 845 
 846   // Check if class of obj supports the Cloneable interface.
 847   // All arrays are considered to be cloneable (See JLS 20.1.5).
 848   // All j.l.r.Reference classes are considered non-cloneable.
 849   if (!klass->is_cloneable() ||
 850       (klass->is_instance_klass() &&
 851        InstanceKlass::cast(klass)->reference_type() != REF_NONE)) {
 852     ResourceMark rm(THREAD);
 853     THROW_MSG_NULL(vmSymbols::java_lang_CloneNotSupportedException(), klass->external_name());
 854   }
 855 
 856   if (klass->is_inline_klass()) {
 857     // Value instances have no identity, so return the current instance instead of allocating a new one
 858     // Value classes cannot have finalizers, so the method can return immediately
 859     return JNIHandles::make_local(THREAD, obj());
 860   }
 861 
 862   // Make shallow object copy
 863   const size_t size = obj->size();
 864   oop new_obj_oop = nullptr;
 865   if (obj->is_array()) {
 866     const int length = ((arrayOop)obj())->length();
 867     new_obj_oop = Universe::heap()->array_allocate(klass, size, length,
 868                                                    /* do_zero */ true, CHECK_NULL);
 869   } else {
 870     new_obj_oop = Universe::heap()->obj_allocate(klass, size, CHECK_NULL);
 871   }
 872 
 873   HeapAccess<>::clone(obj(), new_obj_oop, size);
 874 
 875   Handle new_obj(THREAD, new_obj_oop);
 876   // Caution: this involves a java upcall, so the clone should be
 877   // "gc-robust" by this stage.
 878   if (klass->has_finalizer()) {
 879     assert(obj->is_instance(), "should be instanceOop");
 880     new_obj_oop = InstanceKlass::register_finalizer(instanceOop(new_obj()), CHECK_NULL);
 881     new_obj = Handle(THREAD, new_obj_oop);
 882   }
 883 
 884   return JNIHandles::make_local(THREAD, new_obj());
 885 JVM_END
 886 
 887 // java.lang.ref.Finalizer ////////////////////////////////////////////////////
 888 
 889 JVM_ENTRY(void, JVM_ReportFinalizationComplete(JNIEnv * env, jobject finalizee))
 890   MANAGEMENT_ONLY(FinalizerService::on_complete(JNIHandles::resolve_non_null(finalizee), THREAD);)
 891 JVM_END
 892 
 893 JVM_LEAF(jboolean, JVM_IsFinalizationEnabled(JNIEnv * env))
 894   return InstanceKlass::is_finalization_enabled();
 895 JVM_END
 896 
 897 // jdk.internal.vm.Continuation /////////////////////////////////////////////////////
 898 
 899 JVM_ENTRY(void, JVM_RegisterContinuationMethods(JNIEnv *env, jclass cls))
 900   CONT_RegisterNativeMethods(env, cls);
 901 JVM_END
 902 
 903 // java.io.File ///////////////////////////////////////////////////////////////
 904 
 905 JVM_LEAF(char*, JVM_NativePath(char* path))
 906   return os::native_path(path);
 907 JVM_END
 908 
 909 
 910 // Misc. class handling ///////////////////////////////////////////////////////////
 911 
 912 
 913 JVM_ENTRY(jclass, JVM_GetCallerClass(JNIEnv* env))
 914   // Getting the class of the caller frame.
 915   //
 916   // The call stack at this point looks something like this:
 917   //
 918   // [0] [ @CallerSensitive public jdk.internal.reflect.Reflection.getCallerClass ]
 919   // [1] [ @CallerSensitive API.method                                   ]
 920   // [.] [ (skipped intermediate frames)                                 ]
 921   // [n] [ caller                                                        ]
 922   vframeStream vfst(thread);
 923   // Cf. LibraryCallKit::inline_native_Reflection_getCallerClass
 924   for (int n = 0; !vfst.at_end(); vfst.security_next(), n++) {
 925     Method* m = vfst.method();
 926     assert(m != nullptr, "sanity");
 927     switch (n) {
 928     case 0:
 929       // This must only be called from Reflection.getCallerClass
 930       if (m->intrinsic_id() != vmIntrinsics::_getCallerClass) {
 931         THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), "JVM_GetCallerClass must only be called from Reflection.getCallerClass");
 932       }
 933       // fall-through
 934     case 1:
 935       // Frame 0 and 1 must be caller sensitive.
 936       if (!m->caller_sensitive()) {
 937         THROW_MSG_NULL(vmSymbols::java_lang_InternalError(), err_msg("CallerSensitive annotation expected at frame %d", n));
 938       }
 939       break;
 940     default:
 941       if (!m->is_ignored_by_security_stack_walk()) {
 942         // We have reached the desired frame; return the holder class.
 943         return (jclass) JNIHandles::make_local(THREAD, m->method_holder()->java_mirror());
 944       }
 945       break;
 946     }
 947   }
 948   return nullptr;
 949 JVM_END
 950 
 951 
 952 JVM_ENTRY(jclass, JVM_FindPrimitiveClass(JNIEnv* env, const char* utf))
 953   oop mirror = nullptr;
 954   BasicType t = name2type(utf);
 955   if (t != T_ILLEGAL && !is_reference_type(t)) {
 956     mirror = Universe::java_mirror(t);
 957   }
 958   if (mirror == nullptr) {
 959     THROW_MSG_NULL(vmSymbols::java_lang_ClassNotFoundException(), (char*) utf);
 960   } else {
 961     return (jclass) JNIHandles::make_local(THREAD, mirror);
 962   }
 963 JVM_END
 964 
 965 
 966 // Returns a class loaded by the bootstrap class loader; or null
 967 // if not found.  ClassNotFoundException is not thrown.
 968 // FindClassFromBootLoader is exported to the launcher for windows.
 969 JVM_ENTRY(jclass, JVM_FindClassFromBootLoader(JNIEnv* env,
 970                                               const char* name))
 971   // Java libraries should ensure that name is never null or illegal.
 972   if (name == nullptr || (int)strlen(name) > Symbol::max_length()) {
 973     // It's impossible to create this class;  the name cannot fit
 974     // into the constant pool.
 975     return nullptr;
 976   }
 977   assert(UTF8::is_legal_utf8((const unsigned char*)name, strlen(name), false), "illegal UTF name");
 978 
 979   TempNewSymbol h_name = SymbolTable::new_symbol(name);
 980   Klass* k = SystemDictionary::resolve_or_null(h_name, CHECK_NULL);
 981   if (k == nullptr) {
 982     return nullptr;
 983   }
 984 
 985   if (log_is_enabled(Debug, class, resolve)) {
 986     trace_class_resolution(k);
 987   }
 988   return (jclass) JNIHandles::make_local(THREAD, k->java_mirror());
 989 JVM_END
 990 
 991 // Find a class with this name in this loader, using the caller's protection domain.
 992 JVM_ENTRY(jclass, JVM_FindClassFromCaller(JNIEnv* env, const char* name,
 993                                           jboolean init, jobject loader,
 994                                           jclass caller))
 995   TempNewSymbol h_name =
 996        SystemDictionary::class_name_symbol(name, vmSymbols::java_lang_ClassNotFoundException(),
 997                                            CHECK_NULL);
 998 
 999   oop loader_oop = JNIHandles::resolve(loader);
1000   oop from_class = JNIHandles::resolve(caller);
1001   Handle h_loader(THREAD, loader_oop);
1002 
1003   jclass result = find_class_from_class_loader(env, h_name, init, h_loader,
1004                                                false, THREAD);
1005 
1006   if (log_is_enabled(Debug, class, resolve) && result != nullptr) {
1007     trace_class_resolution(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(result)));
1008   }
1009   return result;
1010 JVM_END
1011 
1012 // Currently only called from the old verifier.
1013 JVM_ENTRY(jclass, JVM_FindClassFromClass(JNIEnv *env, const char *name,
1014                                          jboolean init, jclass from))
1015   TempNewSymbol h_name =
1016        SystemDictionary::class_name_symbol(name, vmSymbols::java_lang_ClassNotFoundException(),
1017                                            CHECK_NULL);
1018   oop from_class_oop = JNIHandles::resolve(from);
1019   Klass* from_class = (from_class_oop == nullptr)
1020                            ? (Klass*)nullptr
1021                            : java_lang_Class::as_Klass(from_class_oop);
1022   oop class_loader = nullptr;
1023   if (from_class != nullptr) {
1024     class_loader = from_class->class_loader();
1025   }
1026   Handle h_loader(THREAD, class_loader);
1027   jclass result = find_class_from_class_loader(env, h_name, init, h_loader, true, thread);
1028 
1029   if (log_is_enabled(Debug, class, resolve) && result != nullptr) {
1030     // this function is generally only used for class loading during verification.
1031     ResourceMark rm;
1032     oop from_mirror = JNIHandles::resolve_non_null(from);
1033     Klass* from_class = java_lang_Class::as_Klass(from_mirror);
1034     const char * from_name = from_class->external_name();
1035 
1036     oop mirror = JNIHandles::resolve_non_null(result);
1037     Klass* to_class = java_lang_Class::as_Klass(mirror);
1038     const char * to = to_class->external_name();
1039     log_debug(class, resolve)("%s %s (verification)", from_name, to);
1040   }
1041 
1042   return result;
1043 JVM_END
1044 
1045 // common code for JVM_DefineClass() and JVM_DefineClassWithSource()
1046 static jclass jvm_define_class_common(const char *name,
1047                                       jobject loader, const jbyte *buf,
1048                                       jsize len, jobject pd, const char *source,
1049                                       TRAPS) {
1050   if (source == nullptr)  source = "__JVM_DefineClass__";
1051 
1052   JavaThread* jt = THREAD;
1053 
1054   PerfClassTraceTime vmtimer(ClassLoader::perf_define_appclass_time(),
1055                              ClassLoader::perf_define_appclass_selftime(),
1056                              ClassLoader::perf_define_appclasses(),
1057                              jt->get_thread_stat()->perf_recursion_counts_addr(),
1058                              jt->get_thread_stat()->perf_timers_addr(),
1059                              PerfClassTraceTime::DEFINE_CLASS);
1060 
1061   if (UsePerfData) {
1062     ClassLoader::perf_app_classfile_bytes_read()->inc(len);
1063   }
1064 
1065   // Class resolution will get the class name from the .class stream if the name is null.
1066   TempNewSymbol class_name = name == nullptr ? nullptr :
1067        SystemDictionary::class_name_symbol(name, vmSymbols::java_lang_NoClassDefFoundError(),
1068                                            CHECK_NULL);
1069 
1070   ResourceMark rm(THREAD);
1071   ClassFileStream st((u1*)buf, len, source);
1072   Handle class_loader (THREAD, JNIHandles::resolve(loader));
1073   Handle protection_domain (THREAD, JNIHandles::resolve(pd));
1074   ClassLoadInfo cl_info(protection_domain);
1075   Klass* k = SystemDictionary::resolve_from_stream(&st, class_name,
1076                                                    class_loader,
1077                                                    cl_info,
1078                                                    CHECK_NULL);
1079 
1080   if (log_is_enabled(Debug, class, resolve)) {
1081     trace_class_resolution(k);
1082   }
1083 
1084   return (jclass) JNIHandles::make_local(THREAD, k->java_mirror());
1085 }
1086 
1087 enum {
1088   NESTMATE              = java_lang_invoke_MemberName::MN_NESTMATE_CLASS,
1089   HIDDEN_CLASS          = java_lang_invoke_MemberName::MN_HIDDEN_CLASS,
1090   STRONG_LOADER_LINK    = java_lang_invoke_MemberName::MN_STRONG_LOADER_LINK,
1091   ACCESS_VM_ANNOTATIONS = java_lang_invoke_MemberName::MN_ACCESS_VM_ANNOTATIONS
1092 };
1093 
1094 /*
1095  * Define a class with the specified flags that indicates if it's a nestmate,
1096  * hidden, or strongly referenced from class loader.
1097  */
1098 static jclass jvm_lookup_define_class(jclass lookup, const char *name,
1099                                       const jbyte *buf, jsize len, jobject pd,
1100                                       jboolean init, int flags, jobject classData, TRAPS) {
1101   ResourceMark rm(THREAD);
1102 
1103   Klass* lookup_k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(lookup));
1104   // Lookup class must be a non-null instance
1105   if (lookup_k == nullptr) {
1106     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Lookup class is null");
1107   }
1108   assert(lookup_k->is_instance_klass(), "Lookup class must be an instance klass");
1109 
1110   Handle class_loader (THREAD, lookup_k->class_loader());
1111 
1112   bool is_nestmate = (flags & NESTMATE) == NESTMATE;
1113   bool is_hidden = (flags & HIDDEN_CLASS) == HIDDEN_CLASS;
1114   bool is_strong = (flags & STRONG_LOADER_LINK) == STRONG_LOADER_LINK;
1115   bool vm_annotations = (flags & ACCESS_VM_ANNOTATIONS) == ACCESS_VM_ANNOTATIONS;
1116 
1117   InstanceKlass* host_class = nullptr;
1118   if (is_nestmate) {
1119     host_class = InstanceKlass::cast(lookup_k)->nest_host(CHECK_NULL);
1120   }
1121 
1122   log_info(class, nestmates)("LookupDefineClass: %s - %s%s, %s, %s, %s",
1123                              name,
1124                              is_nestmate ? "with dynamic nest-host " : "non-nestmate",
1125                              is_nestmate ? host_class->external_name() : "",
1126                              is_hidden ? "hidden" : "not hidden",
1127                              is_strong ? "strong" : "weak",
1128                              vm_annotations ? "with vm annotations" : "without vm annotation");
1129 
1130   if (!is_hidden) {
1131     // classData is only applicable for hidden classes
1132     if (classData != nullptr) {
1133       THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "classData is only applicable for hidden classes");
1134     }
1135     if (is_nestmate) {
1136       THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "dynamic nestmate is only applicable for hidden classes");
1137     }
1138     if (!is_strong) {
1139       THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "an ordinary class must be strongly referenced by its defining loader");
1140     }
1141     if (vm_annotations) {
1142       THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "vm annotations only allowed for hidden classes");
1143     }
1144     if (flags != STRONG_LOADER_LINK) {
1145       THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(),
1146                      err_msg("invalid flag 0x%x", flags));
1147     }
1148   }
1149 
1150   // Class resolution will get the class name from the .class stream if the name is null.
1151   TempNewSymbol class_name = name == nullptr ? nullptr :
1152        SystemDictionary::class_name_symbol(name, vmSymbols::java_lang_NoClassDefFoundError(),
1153                                            CHECK_NULL);
1154 
1155   Handle protection_domain (THREAD, JNIHandles::resolve(pd));
1156   const char* source = is_nestmate ? host_class->external_name() : "__JVM_LookupDefineClass__";
1157   ClassFileStream st((u1*)buf, len, source);
1158 
1159   InstanceKlass* ik = nullptr;
1160   if (!is_hidden) {
1161     ClassLoadInfo cl_info(protection_domain);
1162     ik = SystemDictionary::resolve_from_stream(&st, class_name,
1163                                                class_loader,
1164                                                cl_info,
1165                                                CHECK_NULL);
1166 
1167     if (log_is_enabled(Debug, class, resolve)) {
1168       trace_class_resolution(ik);
1169     }
1170   } else { // hidden
1171     Handle classData_h(THREAD, JNIHandles::resolve(classData));
1172     ClassLoadInfo cl_info(protection_domain,
1173                           host_class,
1174                           classData_h,
1175                           is_hidden,
1176                           is_strong,
1177                           vm_annotations);
1178     ik = SystemDictionary::resolve_from_stream(&st, class_name,
1179                                                class_loader,
1180                                                cl_info,
1181                                                CHECK_NULL);
1182 
1183     // The hidden class loader data has been artificially been kept alive to
1184     // this point. The mirror and any instances of this class have to keep
1185     // it alive afterwards.
1186     ik->class_loader_data()->dec_keep_alive_ref_count();
1187 
1188     if (is_nestmate && log_is_enabled(Debug, class, nestmates)) {
1189       ModuleEntry* module = ik->module();
1190       const char * module_name = module->is_named() ? module->name()->as_C_string() : UNNAMED_MODULE;
1191       log_debug(class, nestmates)("Dynamic nestmate: %s/%s, nest_host %s, %s",
1192                                   module_name,
1193                                   ik->external_name(),
1194                                   host_class->external_name(),
1195                                   ik->is_hidden() ? "is hidden" : "is not hidden");
1196     }
1197   }
1198 
1199   if ((!is_hidden || is_nestmate) && !Reflection::is_same_class_package(lookup_k, ik)) {
1200     // non-hidden class or nestmate class must be in the same package as the Lookup class
1201     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Lookup class and defined class are in different packages");
1202   }
1203 
1204   if (init) {
1205     ik->initialize(CHECK_NULL);
1206   } else {
1207     ik->link_class(CHECK_NULL);
1208   }
1209 
1210   return (jclass) JNIHandles::make_local(THREAD, ik->java_mirror());
1211 }
1212 
1213 JVM_ENTRY(jclass, JVM_DefineClass(JNIEnv *env, const char *name, jobject loader, const jbyte *buf, jsize len, jobject pd))
1214   return jvm_define_class_common(name, loader, buf, len, pd, nullptr, THREAD);
1215 JVM_END
1216 
1217 /*
1218  * Define a class with the specified lookup class.
1219  *  lookup:  Lookup class
1220  *  name:    the name of the class
1221  *  buf:     class bytes
1222  *  len:     length of class bytes
1223  *  pd:      protection domain
1224  *  init:    initialize the class
1225  *  flags:   properties of the class
1226  *  classData: private static pre-initialized field
1227  */
1228 JVM_ENTRY(jclass, JVM_LookupDefineClass(JNIEnv *env, jclass lookup, const char *name, const jbyte *buf,
1229           jsize len, jobject pd, jboolean initialize, int flags, jobject classData))
1230 
1231   if (lookup == nullptr) {
1232     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Lookup class is null");
1233   }
1234 
1235   assert(buf != nullptr, "buf must not be null");
1236 
1237   return jvm_lookup_define_class(lookup, name, buf, len, pd, initialize, flags, classData, THREAD);
1238 JVM_END
1239 
1240 JVM_ENTRY(jclass, JVM_DefineClassWithSource(JNIEnv *env, const char *name, jobject loader, const jbyte *buf, jsize len, jobject pd, const char *source))
1241 
1242   return jvm_define_class_common(name, loader, buf, len, pd, source, THREAD);
1243 JVM_END
1244 
1245 JVM_ENTRY(jclass, JVM_FindLoadedClass(JNIEnv *env, jobject loader, jstring name))
1246   ResourceMark rm(THREAD);
1247 
1248   Handle h_name (THREAD, JNIHandles::resolve_non_null(name));
1249   char* str = java_lang_String::as_utf8_string(h_name());
1250 
1251   // Sanity check, don't expect null
1252   if (str == nullptr) return nullptr;
1253 
1254   // Internalize the string, converting '.' to '/' in string.
1255   char* p = (char*)str;
1256   while (*p != '\0') {
1257     if (*p == '.') {
1258       *p = '/';
1259     }
1260     p++;
1261   }
1262 
1263   const int str_len = (int)(p - str);
1264   if (str_len > Symbol::max_length()) {
1265     // It's impossible to create this class;  the name cannot fit
1266     // into the constant pool.
1267     return nullptr;
1268   }
1269   TempNewSymbol klass_name = SymbolTable::new_symbol(str, str_len);
1270 
1271   // Security Note:
1272   //   The Java level wrapper will perform the necessary security check allowing
1273   //   us to pass the null as the initiating class loader.
1274   Handle h_loader(THREAD, JNIHandles::resolve(loader));
1275   Klass* k = SystemDictionary::find_instance_or_array_klass(THREAD, klass_name, h_loader);
1276 #if INCLUDE_CDS
1277   if (k == nullptr) {
1278     // If the class is not already loaded, try to see if it's in the shared
1279     // archive for the current classloader (h_loader).
1280     k = SystemDictionaryShared::find_or_load_shared_class(klass_name, h_loader, CHECK_NULL);
1281   }
1282 #endif
1283   return (k == nullptr) ? nullptr :
1284             (jclass) JNIHandles::make_local(THREAD, k->java_mirror());
1285 JVM_END
1286 
1287 // Module support //////////////////////////////////////////////////////////////////////////////
1288 
1289 JVM_ENTRY(void, JVM_DefineModule(JNIEnv *env, jobject module, jboolean is_open, jstring version,
1290                                  jstring location, jobjectArray packages))
1291   Handle h_module (THREAD, JNIHandles::resolve(module));
1292   Modules::define_module(h_module, is_open, version, location, packages, CHECK);
1293 JVM_END
1294 
1295 JVM_ENTRY(void, JVM_SetBootLoaderUnnamedModule(JNIEnv *env, jobject module))
1296   Handle h_module (THREAD, JNIHandles::resolve(module));
1297   Modules::set_bootloader_unnamed_module(h_module, CHECK);
1298 JVM_END
1299 
1300 JVM_ENTRY(void, JVM_AddModuleExports(JNIEnv *env, jobject from_module, jstring package, jobject to_module))
1301   Handle h_from_module (THREAD, JNIHandles::resolve(from_module));
1302   Handle h_to_module (THREAD, JNIHandles::resolve(to_module));
1303   Modules::add_module_exports_qualified(h_from_module, package, h_to_module, CHECK);
1304 JVM_END
1305 
1306 JVM_ENTRY(void, JVM_AddModuleExportsToAllUnnamed(JNIEnv *env, jobject from_module, jstring package))
1307   Handle h_from_module (THREAD, JNIHandles::resolve(from_module));
1308   Modules::add_module_exports_to_all_unnamed(h_from_module, package, CHECK);
1309 JVM_END
1310 
1311 JVM_ENTRY(void, JVM_AddModuleExportsToAll(JNIEnv *env, jobject from_module, jstring package))
1312   Handle h_from_module (THREAD, JNIHandles::resolve(from_module));
1313   Modules::add_module_exports(h_from_module, package, Handle(), CHECK);
1314 JVM_END
1315 
1316 JVM_ENTRY (void, JVM_AddReadsModule(JNIEnv *env, jobject from_module, jobject source_module))
1317   Handle h_from_module (THREAD, JNIHandles::resolve(from_module));
1318   Handle h_source_module (THREAD, JNIHandles::resolve(source_module));
1319   Modules::add_reads_module(h_from_module, h_source_module, CHECK);
1320 JVM_END
1321 
1322 JVM_ENTRY(void, JVM_DefineArchivedModules(JNIEnv *env, jobject platform_loader, jobject system_loader))
1323   Handle h_platform_loader (THREAD, JNIHandles::resolve(platform_loader));
1324   Handle h_system_loader (THREAD, JNIHandles::resolve(system_loader));
1325   Modules::define_archived_modules(h_platform_loader, h_system_loader, CHECK);
1326 JVM_END
1327 
1328 // Reflection support //////////////////////////////////////////////////////////////////////////////
1329 
1330 JVM_ENTRY(jstring, JVM_InitClassName(JNIEnv *env, jclass cls))
1331   assert (cls != nullptr, "illegal class");
1332   JvmtiVMObjectAllocEventCollector oam;
1333   ResourceMark rm(THREAD);
1334   HandleMark hm(THREAD);
1335   Handle java_class(THREAD, JNIHandles::resolve(cls));
1336   oop result = java_lang_Class::name(java_class, CHECK_NULL);
1337   return (jstring) JNIHandles::make_local(THREAD, result);
1338 JVM_END
1339 
1340 
1341 JVM_ENTRY(jobjectArray, JVM_GetClassInterfaces(JNIEnv *env, jclass cls))
1342   JvmtiVMObjectAllocEventCollector oam;
1343   oop mirror = JNIHandles::resolve_non_null(cls);
1344 
1345   // Special handling for primitive objects
1346   if (java_lang_Class::is_primitive(mirror)) {
1347     // Primitive objects does not have any interfaces
1348     objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(), 0, CHECK_NULL);
1349     return (jobjectArray) JNIHandles::make_local(THREAD, r);
1350   }
1351 
1352   Klass* klass = java_lang_Class::as_Klass(mirror);
1353   // Figure size of result array
1354   int size;
1355   if (klass->is_instance_klass()) {
1356     InstanceKlass* ik = InstanceKlass::cast(klass);
1357     size = ik->local_interfaces()->length();
1358   } else {
1359     assert(klass->is_objArray_klass() || klass->is_typeArray_klass() || klass->is_flatArray_klass(), "Illegal mirror klass");
1360     size = 2;
1361   }
1362 
1363   // Allocate result array
1364   objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(), size, CHECK_NULL);
1365   objArrayHandle result (THREAD, r);
1366   // Fill in result
1367   if (klass->is_instance_klass()) {
1368     // Regular instance klass, fill in all local interfaces
1369     for (int index = 0; index < size; index++) {
1370       InstanceKlass* ik = InstanceKlass::cast(klass);
1371       Klass* k = ik->local_interfaces()->at(index);
1372       result->obj_at_put(index, k->java_mirror());
1373     }
1374   } else {
1375     // All arrays implement java.lang.Cloneable and java.io.Serializable
1376     result->obj_at_put(0, vmClasses::Cloneable_klass()->java_mirror());
1377     result->obj_at_put(1, vmClasses::Serializable_klass()->java_mirror());
1378   }
1379   return (jobjectArray) JNIHandles::make_local(THREAD, result());
1380 JVM_END
1381 
1382 
1383 JVM_ENTRY(jboolean, JVM_IsHiddenClass(JNIEnv *env, jclass cls))
1384   oop mirror = JNIHandles::resolve_non_null(cls);
1385   if (java_lang_Class::is_primitive(mirror)) {
1386     return JNI_FALSE;
1387   }
1388   Klass* k = java_lang_Class::as_Klass(mirror);
1389   return k->is_hidden();
1390 JVM_END
1391 
1392 class ScopedValueBindingsResolver {
1393 public:
1394   InstanceKlass* Carrier_klass;
1395   ScopedValueBindingsResolver(JavaThread* THREAD) {
1396     Klass *k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_ScopedValue_Carrier(), true, THREAD);
1397     Carrier_klass = InstanceKlass::cast(k);
1398   }
1399 };
1400 
1401 JVM_ENTRY(jobject, JVM_FindScopedValueBindings(JNIEnv *env, jclass cls))
1402   ResourceMark rm(THREAD);
1403   GrowableArray<Handle>* local_array = new GrowableArray<Handle>(12);
1404   JvmtiVMObjectAllocEventCollector oam;
1405 
1406   static ScopedValueBindingsResolver resolver(THREAD);
1407 
1408   // Iterate through Java frames
1409   vframeStream vfst(thread);
1410   for(; !vfst.at_end(); vfst.next()) {
1411     int loc = -1;
1412     // get method of frame
1413     Method* method = vfst.method();
1414 
1415     Symbol *name = method->name();
1416 
1417     InstanceKlass* holder = method->method_holder();
1418     if (name == vmSymbols::runWith_method_name()) {
1419       if (holder == vmClasses::Thread_klass()
1420           || holder == resolver.Carrier_klass) {
1421         loc = 1;
1422       }
1423     }
1424 
1425     if (loc != -1) {
1426       javaVFrame *frame = vfst.asJavaVFrame();
1427       StackValueCollection* locals = frame->locals();
1428       StackValue* head_sv = locals->at(loc); // java/lang/ScopedValue$Snapshot
1429       Handle result = head_sv->get_obj();
1430       assert(!head_sv->obj_is_scalar_replaced(), "found scalar-replaced object");
1431       if (result() != nullptr) {
1432         return JNIHandles::make_local(THREAD, result());
1433       }
1434     }
1435   }
1436 
1437   return nullptr;
1438 JVM_END
1439 
1440 JVM_ENTRY(jobjectArray, JVM_GetDeclaredClasses(JNIEnv *env, jclass ofClass))
1441   JvmtiVMObjectAllocEventCollector oam;
1442   // ofClass is a reference to a java_lang_Class object. The mirror object
1443   // of an InstanceKlass
1444   oop ofMirror = JNIHandles::resolve_non_null(ofClass);
1445   if (java_lang_Class::is_primitive(ofMirror) ||
1446       ! java_lang_Class::as_Klass(ofMirror)->is_instance_klass()) {
1447     oop result = oopFactory::new_objArray(vmClasses::Class_klass(), 0, CHECK_NULL);
1448     return (jobjectArray)JNIHandles::make_local(THREAD, result);
1449   }
1450 
1451   InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(ofMirror));
1452   InnerClassesIterator iter(k);
1453 
1454   if (iter.length() == 0) {
1455     // Neither an inner nor outer class
1456     oop result = oopFactory::new_objArray(vmClasses::Class_klass(), 0, CHECK_NULL);
1457     return (jobjectArray)JNIHandles::make_local(THREAD, result);
1458   }
1459 
1460   // find inner class info
1461   constantPoolHandle cp(thread, k->constants());
1462   int length = iter.length();
1463 
1464   // Allocate temp. result array
1465   objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(), length/4, CHECK_NULL);
1466   objArrayHandle result (THREAD, r);
1467   int members = 0;
1468 
1469   for (; !iter.done(); iter.next()) {
1470     int ioff = iter.inner_class_info_index();
1471     int ooff = iter.outer_class_info_index();
1472 
1473     if (ioff != 0 && ooff != 0) {
1474       // Check to see if the name matches the class we're looking for
1475       // before attempting to find the class.
1476       if (cp->klass_name_at_matches(k, ooff)) {
1477         Klass* outer_klass = cp->klass_at(ooff, CHECK_NULL);
1478         if (outer_klass == k) {
1479            Klass* ik = cp->klass_at(ioff, CHECK_NULL);
1480            InstanceKlass* inner_klass = InstanceKlass::cast(ik);
1481 
1482            // Throws an exception if outer klass has not declared k as
1483            // an inner klass
1484            Reflection::check_for_inner_class(k, inner_klass, true, CHECK_NULL);
1485 
1486            result->obj_at_put(members, inner_klass->java_mirror());
1487            members++;
1488         }
1489       }
1490     }
1491   }
1492 
1493   if (members != length) {
1494     // Return array of right length
1495     objArrayOop res = oopFactory::new_objArray(vmClasses::Class_klass(), members, CHECK_NULL);
1496     for(int i = 0; i < members; i++) {
1497       res->obj_at_put(i, result->obj_at(i));
1498     }
1499     return (jobjectArray)JNIHandles::make_local(THREAD, res);
1500   }
1501 
1502   return (jobjectArray)JNIHandles::make_local(THREAD, result());
1503 JVM_END
1504 
1505 
1506 JVM_ENTRY(jclass, JVM_GetDeclaringClass(JNIEnv *env, jclass ofClass))
1507 {
1508   // ofClass is a reference to a java_lang_Class object.
1509   oop ofMirror = JNIHandles::resolve_non_null(ofClass);
1510   if (java_lang_Class::is_primitive(ofMirror)) {
1511     return nullptr;
1512   }
1513   Klass* klass = java_lang_Class::as_Klass(ofMirror);
1514   if (!klass->is_instance_klass()) {
1515     return nullptr;
1516   }
1517 
1518   bool inner_is_member = false;
1519   Klass* outer_klass
1520     = InstanceKlass::cast(klass)->compute_enclosing_class(&inner_is_member, CHECK_NULL);
1521   if (outer_klass == nullptr)  return nullptr;  // already a top-level class
1522   if (!inner_is_member)  return nullptr;     // a hidden class (inside a method)
1523   return (jclass) JNIHandles::make_local(THREAD, outer_klass->java_mirror());
1524 }
1525 JVM_END
1526 
1527 JVM_ENTRY(jstring, JVM_GetSimpleBinaryName(JNIEnv *env, jclass cls))
1528 {
1529   oop mirror = JNIHandles::resolve_non_null(cls);
1530   if (java_lang_Class::is_primitive(mirror)) {
1531     return nullptr;
1532   }
1533   Klass* klass = java_lang_Class::as_Klass(mirror);
1534   if (!klass->is_instance_klass()) {
1535     return nullptr;
1536   }
1537   InstanceKlass* k = InstanceKlass::cast(klass);
1538   int ooff = 0, noff = 0;
1539   if (k->find_inner_classes_attr(&ooff, &noff, THREAD)) {
1540     if (noff != 0) {
1541       constantPoolHandle i_cp(thread, k->constants());
1542       Symbol* name = i_cp->symbol_at(noff);
1543       Handle str = java_lang_String::create_from_symbol(name, CHECK_NULL);
1544       return (jstring) JNIHandles::make_local(THREAD, str());
1545     }
1546   }
1547   return nullptr;
1548 }
1549 JVM_END
1550 
1551 JVM_ENTRY(jstring, JVM_GetClassSignature(JNIEnv *env, jclass cls))
1552   assert (cls != nullptr, "illegal class");
1553   JvmtiVMObjectAllocEventCollector oam;
1554   ResourceMark rm(THREAD);
1555   oop mirror = JNIHandles::resolve_non_null(cls);
1556   // Return null for arrays and primitives
1557   if (!java_lang_Class::is_primitive(mirror)) {
1558     Klass* k = java_lang_Class::as_Klass(mirror);
1559     if (k->is_instance_klass()) {
1560       Symbol* sym = InstanceKlass::cast(k)->generic_signature();
1561       if (sym == nullptr) return nullptr;
1562       Handle str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
1563       return (jstring) JNIHandles::make_local(THREAD, str());
1564     }
1565   }
1566   return nullptr;
1567 JVM_END
1568 
1569 
1570 JVM_ENTRY(jbyteArray, JVM_GetClassAnnotations(JNIEnv *env, jclass cls))
1571   assert (cls != nullptr, "illegal class");
1572   oop mirror = JNIHandles::resolve_non_null(cls);
1573   // Return null for arrays and primitives
1574   if (!java_lang_Class::is_primitive(mirror)) {
1575     Klass* k = java_lang_Class::as_Klass(mirror);
1576     if (k->is_instance_klass()) {
1577       typeArrayOop a = Annotations::make_java_array(InstanceKlass::cast(k)->class_annotations(), CHECK_NULL);
1578       return (jbyteArray) JNIHandles::make_local(THREAD, a);
1579     }
1580   }
1581   return nullptr;
1582 JVM_END
1583 
1584 
1585 static bool jvm_get_field_common(jobject field, fieldDescriptor& fd) {
1586   // some of this code was adapted from from jni_FromReflectedField
1587 
1588   oop reflected = JNIHandles::resolve_non_null(field);
1589   oop mirror    = java_lang_reflect_Field::clazz(reflected);
1590   Klass* k    = java_lang_Class::as_Klass(mirror);
1591   int slot      = java_lang_reflect_Field::slot(reflected);
1592   int modifiers = java_lang_reflect_Field::modifiers(reflected);
1593 
1594   InstanceKlass* ik = InstanceKlass::cast(k);
1595   int offset = ik->field_offset(slot);
1596 
1597   if (modifiers & JVM_ACC_STATIC) {
1598     // for static fields we only look in the current class
1599     if (!ik->find_local_field_from_offset(offset, true, &fd)) {
1600       assert(false, "cannot find static field");
1601       return false;
1602     }
1603   } else {
1604     // for instance fields we start with the current class and work
1605     // our way up through the superclass chain
1606     if (!ik->find_field_from_offset(offset, false, &fd)) {
1607       assert(false, "cannot find instance field");
1608       return false;
1609     }
1610   }
1611   return true;
1612 }
1613 
1614 static Method* jvm_get_method_common(jobject method) {
1615   // some of this code was adapted from from jni_FromReflectedMethod
1616 
1617   oop reflected = JNIHandles::resolve_non_null(method);
1618   oop mirror    = nullptr;
1619   int slot      = 0;
1620 
1621   if (reflected->klass() == vmClasses::reflect_Constructor_klass()) {
1622     mirror = java_lang_reflect_Constructor::clazz(reflected);
1623     slot   = java_lang_reflect_Constructor::slot(reflected);
1624   } else {
1625     assert(reflected->klass() == vmClasses::reflect_Method_klass(),
1626            "wrong type");
1627     mirror = java_lang_reflect_Method::clazz(reflected);
1628     slot   = java_lang_reflect_Method::slot(reflected);
1629   }
1630   Klass* k = java_lang_Class::as_Klass(mirror);
1631 
1632   Method* m = InstanceKlass::cast(k)->method_with_idnum(slot);
1633   assert(m != nullptr, "cannot find method");
1634   return m;  // caller has to deal with null in product mode
1635 }
1636 
1637 /* Type use annotations support (JDK 1.8) */
1638 
1639 JVM_ENTRY(jbyteArray, JVM_GetClassTypeAnnotations(JNIEnv *env, jclass cls))
1640   assert (cls != nullptr, "illegal class");
1641   ResourceMark rm(THREAD);
1642   // Return null for arrays and primitives
1643   if (!java_lang_Class::is_primitive(JNIHandles::resolve(cls))) {
1644     Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve(cls));
1645     if (k->is_instance_klass()) {
1646       AnnotationArray* type_annotations = InstanceKlass::cast(k)->class_type_annotations();
1647       if (type_annotations != nullptr) {
1648         typeArrayOop a = Annotations::make_java_array(type_annotations, CHECK_NULL);
1649         return (jbyteArray) JNIHandles::make_local(THREAD, a);
1650       }
1651     }
1652   }
1653   return nullptr;
1654 JVM_END
1655 
1656 JVM_ENTRY(jbyteArray, JVM_GetMethodTypeAnnotations(JNIEnv *env, jobject method))
1657   assert (method != nullptr, "illegal method");
1658   // method is a handle to a java.lang.reflect.Method object
1659   Method* m = jvm_get_method_common(method);
1660   if (m == nullptr) {
1661     return nullptr;
1662   }
1663 
1664   AnnotationArray* type_annotations = m->type_annotations();
1665   if (type_annotations != nullptr) {
1666     typeArrayOop a = Annotations::make_java_array(type_annotations, CHECK_NULL);
1667     return (jbyteArray) JNIHandles::make_local(THREAD, a);
1668   }
1669 
1670   return nullptr;
1671 JVM_END
1672 
1673 JVM_ENTRY(jbyteArray, JVM_GetFieldTypeAnnotations(JNIEnv *env, jobject field))
1674   assert (field != nullptr, "illegal field");
1675   fieldDescriptor fd;
1676   bool gotFd = jvm_get_field_common(field, fd);
1677   if (!gotFd) {
1678     return nullptr;
1679   }
1680 
1681   return (jbyteArray) JNIHandles::make_local(THREAD, Annotations::make_java_array(fd.type_annotations(), THREAD));
1682 JVM_END
1683 
1684 static void bounds_check(const constantPoolHandle& cp, jint index, TRAPS) {
1685   if (!cp->is_within_bounds(index)) {
1686     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "Constant pool index out of bounds");
1687   }
1688 }
1689 
1690 JVM_ENTRY(jobjectArray, JVM_GetMethodParameters(JNIEnv *env, jobject method))
1691 {
1692   // method is a handle to a java.lang.reflect.Method object
1693   Method* method_ptr = jvm_get_method_common(method);
1694   methodHandle mh (THREAD, method_ptr);
1695   Handle reflected_method (THREAD, JNIHandles::resolve_non_null(method));
1696   const int num_params = mh->method_parameters_length();
1697 
1698   if (num_params < 0) {
1699     // A -1 return value from method_parameters_length means there is no
1700     // parameter data.  Return null to indicate this to the reflection
1701     // API.
1702     assert(num_params == -1, "num_params should be -1 if it is less than zero");
1703     return (jobjectArray)nullptr;
1704   } else {
1705     // Otherwise, we return something up to reflection, even if it is
1706     // a zero-length array.  Why?  Because in some cases this can
1707     // trigger a MalformedParametersException.
1708 
1709     // make sure all the symbols are properly formatted
1710     for (int i = 0; i < num_params; i++) {
1711       MethodParametersElement* params = mh->method_parameters_start();
1712       int index = params[i].name_cp_index;
1713       constantPoolHandle cp(THREAD, mh->constants());
1714       bounds_check(cp, index, CHECK_NULL);
1715 
1716       if (0 != index && !mh->constants()->tag_at(index).is_utf8()) {
1717         THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(),
1718                        "Wrong type at constant pool index");
1719       }
1720 
1721     }
1722 
1723     objArrayOop result_oop = oopFactory::new_objArray(vmClasses::reflect_Parameter_klass(), num_params, CHECK_NULL);
1724     objArrayHandle result (THREAD, result_oop);
1725 
1726     for (int i = 0; i < num_params; i++) {
1727       MethodParametersElement* params = mh->method_parameters_start();
1728       // For a 0 index, give a null symbol
1729       Symbol* sym = 0 != params[i].name_cp_index ?
1730         mh->constants()->symbol_at(params[i].name_cp_index) : nullptr;
1731       int flags = params[i].flags;
1732       oop param = Reflection::new_parameter(reflected_method, i, sym,
1733                                             flags, CHECK_NULL);
1734       result->obj_at_put(i, param);
1735     }
1736     return (jobjectArray)JNIHandles::make_local(THREAD, result());
1737   }
1738 }
1739 JVM_END
1740 
1741 // New (JDK 1.4) reflection implementation /////////////////////////////////////
1742 
1743 JVM_ENTRY(jobjectArray, JVM_GetClassDeclaredFields(JNIEnv *env, jclass ofClass, jboolean publicOnly))
1744 {
1745   JvmtiVMObjectAllocEventCollector oam;
1746 
1747   oop ofMirror = JNIHandles::resolve_non_null(ofClass);
1748   // Exclude primitive types and array types
1749   if (java_lang_Class::is_primitive(ofMirror) ||
1750       java_lang_Class::as_Klass(ofMirror)->is_array_klass()) {
1751     // Return empty array
1752     oop res = oopFactory::new_objArray(vmClasses::reflect_Field_klass(), 0, CHECK_NULL);
1753     return (jobjectArray) JNIHandles::make_local(THREAD, res);
1754   }
1755 
1756   InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(ofMirror));
1757   constantPoolHandle cp(THREAD, k->constants());
1758 
1759   // Ensure class is linked
1760   k->link_class(CHECK_NULL);
1761 
1762   // Allocate result
1763   int num_fields;
1764 
1765   if (publicOnly) {
1766     num_fields = 0;
1767     for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
1768       if (fs.access_flags().is_public()) ++num_fields;
1769     }
1770   } else {
1771     num_fields = k->java_fields_count();
1772   }
1773 
1774   objArrayOop r = oopFactory::new_objArray(vmClasses::reflect_Field_klass(), num_fields, CHECK_NULL);
1775   objArrayHandle result (THREAD, r);
1776 
1777   int out_idx = 0;
1778   fieldDescriptor fd;
1779   for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
1780     if (!publicOnly || fs.access_flags().is_public()) {
1781       fd.reinitialize(k, fs.to_FieldInfo());
1782       oop field = Reflection::new_field(&fd, CHECK_NULL);
1783       result->obj_at_put(out_idx, field);
1784       ++out_idx;
1785     }
1786   }
1787   assert(out_idx == num_fields, "just checking");
1788   return (jobjectArray) JNIHandles::make_local(THREAD, result());
1789 }
1790 JVM_END
1791 
1792 // A class is a record if and only if it is final and a direct subclass of
1793 // java.lang.Record and has a Record attribute; otherwise, it is not a record.
1794 JVM_ENTRY(jboolean, JVM_IsRecord(JNIEnv *env, jclass cls))
1795 {
1796   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
1797   if (k != nullptr && k->is_instance_klass()) {
1798     InstanceKlass* ik = InstanceKlass::cast(k);
1799     return ik->is_record();
1800   } else {
1801     return false;
1802   }
1803 }
1804 JVM_END
1805 
1806 // Returns an array containing the components of the Record attribute,
1807 // or null if the attribute is not present.
1808 //
1809 // Note that this function returns the components of the Record attribute
1810 // even if the class is not a record.
1811 JVM_ENTRY(jobjectArray, JVM_GetRecordComponents(JNIEnv* env, jclass ofClass))
1812 {
1813   Klass* c = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(ofClass));
1814   assert(c->is_instance_klass(), "must be");
1815   InstanceKlass* ik = InstanceKlass::cast(c);
1816 
1817   Array<RecordComponent*>* components = ik->record_components();
1818   if (components != nullptr) {
1819     JvmtiVMObjectAllocEventCollector oam;
1820     constantPoolHandle cp(THREAD, ik->constants());
1821     int length = components->length();
1822     assert(length >= 0, "unexpected record_components length");
1823     objArrayOop record_components =
1824       oopFactory::new_objArray(vmClasses::RecordComponent_klass(), length, CHECK_NULL);
1825     objArrayHandle components_h (THREAD, record_components);
1826 
1827     for (int x = 0; x < length; x++) {
1828       RecordComponent* component = components->at(x);
1829       assert(component != nullptr, "unexpected null record component");
1830       oop component_oop = java_lang_reflect_RecordComponent::create(ik, component, CHECK_NULL);
1831       components_h->obj_at_put(x, component_oop);
1832     }
1833     return (jobjectArray)JNIHandles::make_local(THREAD, components_h());
1834   }
1835 
1836   return nullptr;
1837 }
1838 JVM_END
1839 
1840 static jobjectArray get_class_declared_methods_helper(
1841                                   JNIEnv *env,
1842                                   jclass ofClass, jboolean publicOnly,
1843                                   bool want_constructor,
1844                                   Klass* klass, TRAPS) {
1845 
1846   JvmtiVMObjectAllocEventCollector oam;
1847 
1848   oop ofMirror = JNIHandles::resolve_non_null(ofClass);
1849   // Exclude primitive types and array types
1850   if (java_lang_Class::is_primitive(ofMirror)
1851       || java_lang_Class::as_Klass(ofMirror)->is_array_klass()) {
1852     // Return empty array
1853     oop res = oopFactory::new_objArray(klass, 0, CHECK_NULL);
1854     return (jobjectArray) JNIHandles::make_local(THREAD, res);
1855   }
1856 
1857   InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(ofMirror));
1858 
1859   // Ensure class is linked
1860   k->link_class(CHECK_NULL);
1861 
1862   Array<Method*>* methods = k->methods();
1863   int methods_length = methods->length();
1864 
1865   // Save original method_idnum in case of redefinition, which can change
1866   // the idnum of obsolete methods.  The new method will have the same idnum
1867   // but if we refresh the methods array, the counts will be wrong.
1868   ResourceMark rm(THREAD);
1869   GrowableArray<int>* idnums = new GrowableArray<int>(methods_length);
1870   int num_methods = 0;
1871 
1872   // Select methods matching the criteria.
1873   for (int i = 0; i < methods_length; i++) {
1874     Method* method = methods->at(i);
1875     if (want_constructor && !method->is_object_constructor()) {
1876       continue;
1877     }
1878     if (!want_constructor &&
1879         (method->is_object_constructor() || method->is_class_initializer() ||
1880          method->is_overpass())) {
1881       continue;
1882     }
1883     if (publicOnly && !method->is_public()) {
1884       continue;
1885     }
1886     idnums->push(method->method_idnum());
1887     ++num_methods;
1888   }
1889 
1890   // Allocate result
1891   objArrayOop r = oopFactory::new_objArray(klass, num_methods, CHECK_NULL);
1892   objArrayHandle result (THREAD, r);
1893 
1894   // Now just put the methods that we selected above, but go by their idnum
1895   // in case of redefinition.  The methods can be redefined at any safepoint,
1896   // so above when allocating the oop array and below when creating reflect
1897   // objects.
1898   for (int i = 0; i < num_methods; i++) {
1899     methodHandle method(THREAD, k->method_with_idnum(idnums->at(i)));
1900     if (method.is_null()) {
1901       // Method may have been deleted and seems this API can handle null
1902       // Otherwise should probably put a method that throws NSME
1903       result->obj_at_put(i, nullptr);
1904     } else {
1905       oop m;
1906       if (want_constructor) {
1907         assert(method->is_object_constructor(), "must be");
1908         m = Reflection::new_constructor(method, CHECK_NULL);
1909       } else {
1910         m = Reflection::new_method(method, false, CHECK_NULL);
1911       }
1912       result->obj_at_put(i, m);
1913     }
1914   }
1915 
1916   return (jobjectArray) JNIHandles::make_local(THREAD, result());
1917 }
1918 
1919 JVM_ENTRY(jobjectArray, JVM_GetClassDeclaredMethods(JNIEnv *env, jclass ofClass, jboolean publicOnly))
1920 {
1921   return get_class_declared_methods_helper(env, ofClass, publicOnly,
1922                                            /*want_constructor*/ false,
1923                                            vmClasses::reflect_Method_klass(), THREAD);
1924 }
1925 JVM_END
1926 
1927 JVM_ENTRY(jobjectArray, JVM_GetClassDeclaredConstructors(JNIEnv *env, jclass ofClass, jboolean publicOnly))
1928 {
1929   return get_class_declared_methods_helper(env, ofClass, publicOnly,
1930                                            /*want_constructor*/ true,
1931                                            vmClasses::reflect_Constructor_klass(), THREAD);
1932 }
1933 JVM_END
1934 
1935 JVM_ENTRY(jint, JVM_GetClassAccessFlags(JNIEnv *env, jclass cls))
1936 {
1937   oop mirror = JNIHandles::resolve_non_null(cls);
1938   if (java_lang_Class::is_primitive(mirror)) {
1939     // Primitive type
1940     return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC;
1941   }
1942 
1943   Klass* k = java_lang_Class::as_Klass(mirror);
1944   return k->access_flags().as_class_flags();
1945 }
1946 JVM_END
1947 
1948 JVM_ENTRY(jboolean, JVM_AreNestMates(JNIEnv *env, jclass current, jclass member))
1949 {
1950   Klass* c = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(current));
1951   assert(c->is_instance_klass(), "must be");
1952   InstanceKlass* ck = InstanceKlass::cast(c);
1953   Klass* m = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(member));
1954   assert(m->is_instance_klass(), "must be");
1955   InstanceKlass* mk = InstanceKlass::cast(m);
1956   return ck->has_nestmate_access_to(mk, THREAD);
1957 }
1958 JVM_END
1959 
1960 JVM_ENTRY(jclass, JVM_GetNestHost(JNIEnv* env, jclass current))
1961 {
1962   // current is not a primitive or array class
1963   Klass* c = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(current));
1964   assert(c->is_instance_klass(), "must be");
1965   InstanceKlass* ck = InstanceKlass::cast(c);
1966   InstanceKlass* host = ck->nest_host(THREAD);
1967   return (jclass) (host == nullptr ? nullptr :
1968                    JNIHandles::make_local(THREAD, host->java_mirror()));
1969 }
1970 JVM_END
1971 
1972 JVM_ENTRY(jobjectArray, JVM_GetNestMembers(JNIEnv* env, jclass current))
1973 {
1974   // current is not a primitive or array class
1975   ResourceMark rm(THREAD);
1976   Klass* c = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(current));
1977   assert(c->is_instance_klass(), "must be");
1978   InstanceKlass* ck = InstanceKlass::cast(c);
1979   InstanceKlass* host = ck->nest_host(THREAD);
1980 
1981   log_trace(class, nestmates)("Calling GetNestMembers for type %s with nest-host %s",
1982                               ck->external_name(), host->external_name());
1983   {
1984     JvmtiVMObjectAllocEventCollector oam;
1985     Array<u2>* members = host->nest_members();
1986     int length = members == nullptr ? 0 : members->length();
1987 
1988     log_trace(class, nestmates)(" - host has %d listed nest members", length);
1989 
1990     // nest host is first in the array so make it one bigger
1991     objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(),
1992                                              length + 1, CHECK_NULL);
1993     objArrayHandle result(THREAD, r);
1994     result->obj_at_put(0, host->java_mirror());
1995     if (length != 0) {
1996       int count = 0;
1997       for (int i = 0; i < length; i++) {
1998         int cp_index = members->at(i);
1999         Klass* k = host->constants()->klass_at(cp_index, THREAD);
2000         if (HAS_PENDING_EXCEPTION) {
2001           if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
2002             return nullptr; // propagate VMEs
2003           }
2004           if (log_is_enabled(Trace, class, nestmates)) {
2005             stringStream ss;
2006             char* target_member_class = host->constants()->klass_name_at(cp_index)->as_C_string();
2007             ss.print(" - resolution of nest member %s failed: ", target_member_class);
2008             java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
2009             log_trace(class, nestmates)("%s", ss.as_string());
2010           }
2011           CLEAR_PENDING_EXCEPTION;
2012           continue;
2013         }
2014         if (k->is_instance_klass()) {
2015           InstanceKlass* ik = InstanceKlass::cast(k);
2016           InstanceKlass* nest_host_k = ik->nest_host(CHECK_NULL);
2017           if (nest_host_k == host) {
2018             result->obj_at_put(count+1, k->java_mirror());
2019             count++;
2020             log_trace(class, nestmates)(" - [%d] = %s", count, ik->external_name());
2021           } else {
2022             log_trace(class, nestmates)(" - skipping member %s with different host %s",
2023                                         ik->external_name(), nest_host_k->external_name());
2024           }
2025         } else {
2026           log_trace(class, nestmates)(" - skipping member %s that is not an instance class",
2027                                       k->external_name());
2028         }
2029       }
2030       if (count < length) {
2031         // we had invalid entries so we need to compact the array
2032         log_trace(class, nestmates)(" - compacting array from length %d to %d",
2033                                     length + 1, count + 1);
2034 
2035         objArrayOop r2 = oopFactory::new_objArray(vmClasses::Class_klass(),
2036                                                   count + 1, CHECK_NULL);
2037         objArrayHandle result2(THREAD, r2);
2038         for (int i = 0; i < count + 1; i++) {
2039           result2->obj_at_put(i, result->obj_at(i));
2040         }
2041         return (jobjectArray)JNIHandles::make_local(THREAD, result2());
2042       }
2043     }
2044     else {
2045       assert(host == ck || ck->is_hidden(), "must be singleton nest or dynamic nestmate");
2046     }
2047     return (jobjectArray)JNIHandles::make_local(THREAD, result());
2048   }
2049 }
2050 JVM_END
2051 
2052 JVM_ENTRY(jobjectArray, JVM_GetPermittedSubclasses(JNIEnv* env, jclass current))
2053 {
2054   oop mirror = JNIHandles::resolve_non_null(current);
2055   assert(!java_lang_Class::is_primitive(mirror), "should not be");
2056   Klass* c = java_lang_Class::as_Klass(mirror);
2057   assert(c->is_instance_klass(), "must be");
2058   InstanceKlass* ik = InstanceKlass::cast(c);
2059   ResourceMark rm(THREAD);
2060   log_trace(class, sealed)("Calling GetPermittedSubclasses for %s type %s",
2061                            ik->is_sealed() ? "sealed" : "non-sealed", ik->external_name());
2062   if (ik->is_sealed()) {
2063     JvmtiVMObjectAllocEventCollector oam;
2064     Array<u2>* subclasses = ik->permitted_subclasses();
2065     int length = subclasses->length();
2066 
2067     log_trace(class, sealed)(" - sealed class has %d permitted subclasses", length);
2068 
2069     objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(),
2070                                              length, CHECK_NULL);
2071     objArrayHandle result(THREAD, r);
2072     int count = 0;
2073     for (int i = 0; i < length; i++) {
2074       int cp_index = subclasses->at(i);
2075       Klass* k = ik->constants()->klass_at(cp_index, THREAD);
2076       if (HAS_PENDING_EXCEPTION) {
2077         if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
2078           return nullptr; // propagate VMEs
2079         }
2080         if (log_is_enabled(Trace, class, sealed)) {
2081           stringStream ss;
2082           char* permitted_subclass = ik->constants()->klass_name_at(cp_index)->as_C_string();
2083           ss.print(" - resolution of permitted subclass %s failed: ", permitted_subclass);
2084           java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
2085           log_trace(class, sealed)("%s", ss.as_string());
2086         }
2087 
2088         CLEAR_PENDING_EXCEPTION;
2089         continue;
2090       }
2091       if (k->is_instance_klass()) {
2092         result->obj_at_put(count++, k->java_mirror());
2093         log_trace(class, sealed)(" - [%d] = %s", count, k->external_name());
2094       }
2095     }
2096     if (count < length) {
2097       // we had invalid entries so we need to compact the array
2098       objArrayOop r2 = oopFactory::new_objArray(vmClasses::Class_klass(),
2099                                                 count, CHECK_NULL);
2100       objArrayHandle result2(THREAD, r2);
2101       for (int i = 0; i < count; i++) {
2102         result2->obj_at_put(i, result->obj_at(i));
2103       }
2104       return (jobjectArray)JNIHandles::make_local(THREAD, result2());
2105     }
2106     return (jobjectArray)JNIHandles::make_local(THREAD, result());
2107   } else {
2108     return nullptr;
2109   }
2110 }
2111 JVM_END
2112 
2113 // Constant pool access //////////////////////////////////////////////////////////
2114 
2115 JVM_ENTRY(jobject, JVM_GetClassConstantPool(JNIEnv *env, jclass cls))
2116 {
2117   JvmtiVMObjectAllocEventCollector oam;
2118   oop mirror = JNIHandles::resolve_non_null(cls);
2119   // Return null for primitives and arrays
2120   if (!java_lang_Class::is_primitive(mirror)) {
2121     Klass* k = java_lang_Class::as_Klass(mirror);
2122     if (k->is_instance_klass()) {
2123       InstanceKlass* k_h = InstanceKlass::cast(k);
2124       Handle jcp = reflect_ConstantPool::create(CHECK_NULL);
2125       reflect_ConstantPool::set_cp(jcp(), k_h->constants());
2126       return JNIHandles::make_local(THREAD, jcp());
2127     }
2128   }
2129   return nullptr;
2130 }
2131 JVM_END
2132 
2133 
2134 JVM_ENTRY(jint, JVM_ConstantPoolGetSize(JNIEnv *env, jobject obj, jobject unused))
2135 {
2136   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2137   return cp->length();
2138 }
2139 JVM_END
2140 
2141 
2142 JVM_ENTRY(jclass, JVM_ConstantPoolGetClassAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2143 {
2144   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2145   bounds_check(cp, index, CHECK_NULL);
2146   constantTag tag = cp->tag_at(index);
2147   if (!tag.is_klass() && !tag.is_unresolved_klass()) {
2148     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2149   }
2150   Klass* k = cp->klass_at(index, CHECK_NULL);
2151   return (jclass) JNIHandles::make_local(THREAD, k->java_mirror());
2152 }
2153 JVM_END
2154 
2155 JVM_ENTRY(jclass, JVM_ConstantPoolGetClassAtIfLoaded(JNIEnv *env, jobject obj, jobject unused, jint index))
2156 {
2157   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2158   bounds_check(cp, index, CHECK_NULL);
2159   constantTag tag = cp->tag_at(index);
2160   if (!tag.is_klass() && !tag.is_unresolved_klass()) {
2161     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2162   }
2163   Klass* k = ConstantPool::klass_at_if_loaded(cp, index);
2164   if (k == nullptr) return nullptr;
2165   return (jclass) JNIHandles::make_local(THREAD, k->java_mirror());
2166 }
2167 JVM_END
2168 
2169 static jobject get_method_at_helper(const constantPoolHandle& cp, jint index, bool force_resolution, TRAPS) {
2170   constantTag tag = cp->tag_at(index);
2171   if (!tag.is_method() && !tag.is_interface_method()) {
2172     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2173   }
2174   int klass_ref  = cp->uncached_klass_ref_index_at(index);
2175   Klass* k_o;
2176   if (force_resolution) {
2177     k_o = cp->klass_at(klass_ref, CHECK_NULL);
2178   } else {
2179     k_o = ConstantPool::klass_at_if_loaded(cp, klass_ref);
2180     if (k_o == nullptr) return nullptr;
2181   }
2182   InstanceKlass* k = InstanceKlass::cast(k_o);
2183   Symbol* name = cp->uncached_name_ref_at(index);
2184   Symbol* sig  = cp->uncached_signature_ref_at(index);
2185   methodHandle m (THREAD, k->find_method(name, sig));
2186   if (m.is_null()) {
2187     THROW_MSG_NULL(vmSymbols::java_lang_RuntimeException(), "Unable to look up method in target class");
2188   }
2189   oop method;
2190   if (m->is_object_constructor()) {
2191     method = Reflection::new_constructor(m, CHECK_NULL);
2192   } else {
2193     method = Reflection::new_method(m, true, CHECK_NULL);
2194   }
2195   return JNIHandles::make_local(THREAD, method);
2196 }
2197 
2198 JVM_ENTRY(jobject, JVM_ConstantPoolGetMethodAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2199 {
2200   JvmtiVMObjectAllocEventCollector oam;
2201   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2202   bounds_check(cp, index, CHECK_NULL);
2203   jobject res = get_method_at_helper(cp, index, true, CHECK_NULL);
2204   return res;
2205 }
2206 JVM_END
2207 
2208 JVM_ENTRY(jobject, JVM_ConstantPoolGetMethodAtIfLoaded(JNIEnv *env, jobject obj, jobject unused, jint index))
2209 {
2210   JvmtiVMObjectAllocEventCollector oam;
2211   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2212   bounds_check(cp, index, CHECK_NULL);
2213   jobject res = get_method_at_helper(cp, index, false, CHECK_NULL);
2214   return res;
2215 }
2216 JVM_END
2217 
2218 static jobject get_field_at_helper(constantPoolHandle cp, jint index, bool force_resolution, TRAPS) {
2219   constantTag tag = cp->tag_at(index);
2220   if (!tag.is_field()) {
2221     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2222   }
2223   int klass_ref  = cp->uncached_klass_ref_index_at(index);
2224   Klass* k_o;
2225   if (force_resolution) {
2226     k_o = cp->klass_at(klass_ref, CHECK_NULL);
2227   } else {
2228     k_o = ConstantPool::klass_at_if_loaded(cp, klass_ref);
2229     if (k_o == nullptr) return nullptr;
2230   }
2231   InstanceKlass* k = InstanceKlass::cast(k_o);
2232   Symbol* name = cp->uncached_name_ref_at(index);
2233   Symbol* sig  = cp->uncached_signature_ref_at(index);
2234   fieldDescriptor fd;
2235   Klass* target_klass = k->find_field(name, sig, &fd);
2236   if (target_klass == nullptr) {
2237     THROW_MSG_NULL(vmSymbols::java_lang_RuntimeException(), "Unable to look up field in target class");
2238   }
2239   oop field = Reflection::new_field(&fd, CHECK_NULL);
2240   return JNIHandles::make_local(THREAD, field);
2241 }
2242 
2243 JVM_ENTRY(jobject, JVM_ConstantPoolGetFieldAt(JNIEnv *env, jobject obj, jobject unusedl, jint index))
2244 {
2245   JvmtiVMObjectAllocEventCollector oam;
2246   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2247   bounds_check(cp, index, CHECK_NULL);
2248   jobject res = get_field_at_helper(cp, index, true, CHECK_NULL);
2249   return res;
2250 }
2251 JVM_END
2252 
2253 JVM_ENTRY(jobject, JVM_ConstantPoolGetFieldAtIfLoaded(JNIEnv *env, jobject obj, jobject unused, jint index))
2254 {
2255   JvmtiVMObjectAllocEventCollector oam;
2256   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2257   bounds_check(cp, index, CHECK_NULL);
2258   jobject res = get_field_at_helper(cp, index, false, CHECK_NULL);
2259   return res;
2260 }
2261 JVM_END
2262 
2263 JVM_ENTRY(jobjectArray, JVM_ConstantPoolGetMemberRefInfoAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2264 {
2265   JvmtiVMObjectAllocEventCollector oam;
2266   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2267   bounds_check(cp, index, CHECK_NULL);
2268   constantTag tag = cp->tag_at(index);
2269   if (!tag.is_field_or_method()) {
2270     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2271   }
2272   int klass_ref = cp->uncached_klass_ref_index_at(index);
2273   Symbol*  klass_name  = cp->klass_name_at(klass_ref);
2274   Symbol*  member_name = cp->uncached_name_ref_at(index);
2275   Symbol*  member_sig  = cp->uncached_signature_ref_at(index);
2276   objArrayOop  dest_o = oopFactory::new_objArray(vmClasses::String_klass(), 3, CHECK_NULL);
2277   objArrayHandle dest(THREAD, dest_o);
2278   Handle str = java_lang_String::create_from_symbol(klass_name, CHECK_NULL);
2279   dest->obj_at_put(0, str());
2280   str = java_lang_String::create_from_symbol(member_name, CHECK_NULL);
2281   dest->obj_at_put(1, str());
2282   str = java_lang_String::create_from_symbol(member_sig, CHECK_NULL);
2283   dest->obj_at_put(2, str());
2284   return (jobjectArray) JNIHandles::make_local(THREAD, dest());
2285 }
2286 JVM_END
2287 
2288 JVM_ENTRY(jint, JVM_ConstantPoolGetClassRefIndexAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2289 {
2290   JvmtiVMObjectAllocEventCollector oam;
2291   constantPoolHandle cp(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2292   bounds_check(cp, index, CHECK_0);
2293   constantTag tag = cp->tag_at(index);
2294   if (!tag.is_field_or_method()) {
2295     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2296   }
2297   return (jint) cp->uncached_klass_ref_index_at(index);
2298 }
2299 JVM_END
2300 
2301 JVM_ENTRY(jint, JVM_ConstantPoolGetNameAndTypeRefIndexAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2302 {
2303   JvmtiVMObjectAllocEventCollector oam;
2304   constantPoolHandle cp(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2305   bounds_check(cp, index, CHECK_0);
2306   constantTag tag = cp->tag_at(index);
2307   if (!tag.is_invoke_dynamic() && !tag.is_field_or_method()) {
2308     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2309   }
2310   return (jint) cp->uncached_name_and_type_ref_index_at(index);
2311 }
2312 JVM_END
2313 
2314 JVM_ENTRY(jobjectArray, JVM_ConstantPoolGetNameAndTypeRefInfoAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2315 {
2316   JvmtiVMObjectAllocEventCollector oam;
2317   constantPoolHandle cp(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2318   bounds_check(cp, index, CHECK_NULL);
2319   constantTag tag = cp->tag_at(index);
2320   if (!tag.is_name_and_type()) {
2321     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2322   }
2323   Symbol* member_name = cp->symbol_at(cp->name_ref_index_at(index));
2324   Symbol* member_sig = cp->symbol_at(cp->signature_ref_index_at(index));
2325   objArrayOop dest_o = oopFactory::new_objArray(vmClasses::String_klass(), 2, CHECK_NULL);
2326   objArrayHandle dest(THREAD, dest_o);
2327   Handle str = java_lang_String::create_from_symbol(member_name, CHECK_NULL);
2328   dest->obj_at_put(0, str());
2329   str = java_lang_String::create_from_symbol(member_sig, CHECK_NULL);
2330   dest->obj_at_put(1, str());
2331   return (jobjectArray) JNIHandles::make_local(THREAD, dest());
2332 }
2333 JVM_END
2334 
2335 JVM_ENTRY(jint, JVM_ConstantPoolGetIntAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2336 {
2337   constantPoolHandle cp = constantPoolHandle(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_int()) {
2341     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2342   }
2343   return cp->int_at(index);
2344 }
2345 JVM_END
2346 
2347 JVM_ENTRY(jlong, JVM_ConstantPoolGetLongAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2348 {
2349   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2350   bounds_check(cp, index, CHECK_(0L));
2351   constantTag tag = cp->tag_at(index);
2352   if (!tag.is_long()) {
2353     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2354   }
2355   return cp->long_at(index);
2356 }
2357 JVM_END
2358 
2359 JVM_ENTRY(jfloat, JVM_ConstantPoolGetFloatAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2360 {
2361   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2362   bounds_check(cp, index, CHECK_(0.0f));
2363   constantTag tag = cp->tag_at(index);
2364   if (!tag.is_float()) {
2365     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2366   }
2367   return cp->float_at(index);
2368 }
2369 JVM_END
2370 
2371 JVM_ENTRY(jdouble, JVM_ConstantPoolGetDoubleAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2372 {
2373   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2374   bounds_check(cp, index, CHECK_(0.0));
2375   constantTag tag = cp->tag_at(index);
2376   if (!tag.is_double()) {
2377     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2378   }
2379   return cp->double_at(index);
2380 }
2381 JVM_END
2382 
2383 JVM_ENTRY(jstring, JVM_ConstantPoolGetStringAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2384 {
2385   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2386   bounds_check(cp, index, CHECK_NULL);
2387   constantTag tag = cp->tag_at(index);
2388   if (!tag.is_string()) {
2389     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2390   }
2391   oop str = cp->string_at(index, CHECK_NULL);
2392   return (jstring) JNIHandles::make_local(THREAD, str);
2393 }
2394 JVM_END
2395 
2396 JVM_ENTRY(jstring, JVM_ConstantPoolGetUTF8At(JNIEnv *env, jobject obj, jobject unused, jint index))
2397 {
2398   JvmtiVMObjectAllocEventCollector oam;
2399   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2400   bounds_check(cp, index, CHECK_NULL);
2401   constantTag tag = cp->tag_at(index);
2402   if (!tag.is_symbol()) {
2403     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2404   }
2405   Symbol* sym = cp->symbol_at(index);
2406   Handle str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
2407   return (jstring) JNIHandles::make_local(THREAD, str());
2408 }
2409 JVM_END
2410 
2411 JVM_ENTRY(jbyte, JVM_ConstantPoolGetTagAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2412 {
2413   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2414   bounds_check(cp, index, CHECK_0);
2415   constantTag tag = cp->tag_at(index);
2416   jbyte result = tag.value();
2417   // If returned tag values are not from the JVM spec, e.g. tags from 100 to 105,
2418   // they are changed to the corresponding tags from the JVM spec, so that java code in
2419   // sun.reflect.ConstantPool will return only tags from the JVM spec, not internal ones.
2420   if (tag.is_klass_or_reference()) {
2421       result = JVM_CONSTANT_Class;
2422   } else if (tag.is_string_index()) {
2423       result = JVM_CONSTANT_String;
2424   } else if (tag.is_method_type_in_error()) {
2425       result = JVM_CONSTANT_MethodType;
2426   } else if (tag.is_method_handle_in_error()) {
2427       result = JVM_CONSTANT_MethodHandle;
2428   } else if (tag.is_dynamic_constant_in_error()) {
2429       result = JVM_CONSTANT_Dynamic;
2430   }
2431   return result;
2432 }
2433 JVM_END
2434 
2435 // Assertion support. //////////////////////////////////////////////////////////
2436 
2437 JVM_ENTRY(jboolean, JVM_DesiredAssertionStatus(JNIEnv *env, jclass unused, jclass cls))
2438   assert(cls != nullptr, "bad class");
2439 
2440   oop r = JNIHandles::resolve(cls);
2441   assert(! java_lang_Class::is_primitive(r), "primitive classes not allowed");
2442   if (java_lang_Class::is_primitive(r)) return false;
2443 
2444   Klass* k = java_lang_Class::as_Klass(r);
2445   assert(k->is_instance_klass(), "must be an instance klass");
2446   if (!k->is_instance_klass()) return false;
2447 
2448   ResourceMark rm(THREAD);
2449   const char* name = k->name()->as_C_string();
2450   bool system_class = k->class_loader() == nullptr;
2451   return JavaAssertions::enabled(name, system_class);
2452 
2453 JVM_END
2454 
2455 
2456 // Return a new AssertionStatusDirectives object with the fields filled in with
2457 // command-line assertion arguments (i.e., -ea, -da).
2458 JVM_ENTRY(jobject, JVM_AssertionStatusDirectives(JNIEnv *env, jclass unused))
2459   JvmtiVMObjectAllocEventCollector oam;
2460   oop asd = JavaAssertions::createAssertionStatusDirectives(CHECK_NULL);
2461   return JNIHandles::make_local(THREAD, asd);
2462 JVM_END
2463 
2464 // Verification ////////////////////////////////////////////////////////////////////////////////
2465 
2466 // Reflection for the verifier /////////////////////////////////////////////////////////////////
2467 
2468 // RedefineClasses support: bug 6214132 caused verification to fail.
2469 // All functions from this section should call the jvmtiThreadSate function:
2470 //   Klass* class_to_verify_considering_redefinition(Klass* klass).
2471 // The function returns a Klass* of the _scratch_class if the verifier
2472 // was invoked in the middle of the class redefinition.
2473 // Otherwise it returns its argument value which is the _the_class Klass*.
2474 // Please, refer to the description in the jvmtiThreadState.hpp.
2475 
2476 JVM_ENTRY(jboolean, JVM_IsInterface(JNIEnv *env, jclass cls))
2477   oop mirror = JNIHandles::resolve_non_null(cls);
2478   if (java_lang_Class::is_primitive(mirror)) {
2479     return JNI_FALSE;
2480   }
2481   Klass* k = java_lang_Class::as_Klass(mirror);
2482   // This isn't necessary since answer is the same since redefinition
2483   // has already checked this matches for the scratch class.
2484   // k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2485   jboolean result = k->is_interface();
2486   assert(!result || k->is_instance_klass(),
2487          "all interfaces are instance types");
2488   return result;
2489 JVM_END
2490 
2491 
2492 JVM_ENTRY(const char*, JVM_GetClassNameUTF(JNIEnv *env, jclass cls))
2493   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2494   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2495   return k->name()->as_utf8();
2496 JVM_END
2497 
2498 
2499 JVM_ENTRY(void, JVM_GetClassCPTypes(JNIEnv *env, jclass cls, unsigned char *types))
2500   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2501   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2502   // types will have length zero if this is not an InstanceKlass
2503   // (length is determined by call to JVM_GetClassCPEntriesCount)
2504   if (k->is_instance_klass()) {
2505     ConstantPool* cp = InstanceKlass::cast(k)->constants();
2506     for (int index = cp->length() - 1; index >= 0; index--) {
2507       constantTag tag = cp->tag_at(index);
2508       types[index] = (tag.is_unresolved_klass()) ? (unsigned char) JVM_CONSTANT_Class : tag.value();
2509     }
2510   }
2511 JVM_END
2512 
2513 
2514 JVM_ENTRY(jint, JVM_GetClassCPEntriesCount(JNIEnv *env, jclass cls))
2515   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2516   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2517   return (!k->is_instance_klass()) ? 0 : InstanceKlass::cast(k)->constants()->length();
2518 JVM_END
2519 
2520 
2521 JVM_ENTRY(jint, JVM_GetClassFieldsCount(JNIEnv *env, jclass cls))
2522   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2523   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2524   return (!k->is_instance_klass()) ? 0 : InstanceKlass::cast(k)->java_fields_count();
2525 JVM_END
2526 
2527 
2528 JVM_ENTRY(jint, JVM_GetClassMethodsCount(JNIEnv *env, jclass cls))
2529   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2530   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2531   return (!k->is_instance_klass()) ? 0 : InstanceKlass::cast(k)->methods()->length();
2532 JVM_END
2533 
2534 
2535 // The following methods, used for the verifier, are never called with
2536 // array klasses, so a direct cast to InstanceKlass is safe.
2537 // Typically, these methods are called in a loop with bounds determined
2538 // by the results of JVM_GetClass{Fields,Methods}Count, which return
2539 // zero for arrays.
2540 JVM_ENTRY(void, JVM_GetMethodIxExceptionIndexes(JNIEnv *env, jclass cls, jint method_index, unsigned short *exceptions))
2541   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2542   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2543   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2544   int length = method->checked_exceptions_length();
2545   if (length > 0) {
2546     CheckedExceptionElement* table= method->checked_exceptions_start();
2547     for (int i = 0; i < length; i++) {
2548       exceptions[i] = table[i].class_cp_index;
2549     }
2550   }
2551 JVM_END
2552 
2553 
2554 JVM_ENTRY(jint, JVM_GetMethodIxExceptionsCount(JNIEnv *env, jclass cls, jint method_index))
2555   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2556   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2557   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2558   return method->checked_exceptions_length();
2559 JVM_END
2560 
2561 
2562 JVM_ENTRY(void, JVM_GetMethodIxByteCode(JNIEnv *env, jclass cls, jint method_index, unsigned char *code))
2563   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2564   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2565   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2566   memcpy(code, method->code_base(), method->code_size());
2567 JVM_END
2568 
2569 
2570 JVM_ENTRY(jint, JVM_GetMethodIxByteCodeLength(JNIEnv *env, jclass cls, jint method_index))
2571   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2572   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2573   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2574   return method->code_size();
2575 JVM_END
2576 
2577 
2578 JVM_ENTRY(void, JVM_GetMethodIxExceptionTableEntry(JNIEnv *env, jclass cls, jint method_index, jint entry_index, JVM_ExceptionTableEntryType *entry))
2579   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2580   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2581   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2582   ExceptionTable extable(method);
2583   entry->start_pc   = extable.start_pc(entry_index);
2584   entry->end_pc     = extable.end_pc(entry_index);
2585   entry->handler_pc = extable.handler_pc(entry_index);
2586   entry->catchType  = extable.catch_type_index(entry_index);
2587 JVM_END
2588 
2589 
2590 JVM_ENTRY(jint, JVM_GetMethodIxExceptionTableLength(JNIEnv *env, jclass cls, int method_index))
2591   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2592   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2593   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2594   return method->exception_table_length();
2595 JVM_END
2596 
2597 
2598 JVM_ENTRY(jint, JVM_GetMethodIxModifiers(JNIEnv *env, jclass cls, int method_index))
2599   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2600   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2601   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2602   return method->access_flags().as_method_flags();
2603 JVM_END
2604 
2605 
2606 JVM_ENTRY(jint, JVM_GetFieldIxModifiers(JNIEnv *env, jclass cls, int field_index))
2607   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2608   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2609   return InstanceKlass::cast(k)->field_access_flags(field_index);
2610 JVM_END
2611 
2612 
2613 JVM_ENTRY(jint, JVM_GetMethodIxLocalsCount(JNIEnv *env, jclass cls, int method_index))
2614   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2615   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2616   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2617   return method->max_locals();
2618 JVM_END
2619 
2620 
2621 JVM_ENTRY(jint, JVM_GetMethodIxArgsSize(JNIEnv *env, jclass cls, int 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->size_of_parameters();
2626 JVM_END
2627 
2628 
2629 JVM_ENTRY(jint, JVM_GetMethodIxMaxStack(JNIEnv *env, jclass cls, int method_index))
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   return method->verifier_max_stack();
2634 JVM_END
2635 
2636 
2637 JVM_ENTRY(jboolean, JVM_IsConstructorIx(JNIEnv *env, jclass cls, int method_index))
2638   ResourceMark rm(THREAD);
2639   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2640   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2641   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2642   return method->is_object_constructor();
2643 JVM_END
2644 
2645 
2646 JVM_ENTRY(jboolean, JVM_IsVMGeneratedMethodIx(JNIEnv *env, jclass cls, int method_index))
2647   ResourceMark rm(THREAD);
2648   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2649   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2650   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2651   return method->is_overpass();
2652 JVM_END
2653 
2654 JVM_ENTRY(const char*, JVM_GetMethodIxNameUTF(JNIEnv *env, jclass cls, jint method_index))
2655   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2656   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2657   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2658   return method->name()->as_utf8();
2659 JVM_END
2660 
2661 
2662 JVM_ENTRY(const char*, JVM_GetMethodIxSignatureUTF(JNIEnv *env, jclass cls, jint method_index))
2663   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2664   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2665   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2666   return method->signature()->as_utf8();
2667 JVM_END
2668 
2669 /**
2670  * All of these JVM_GetCP-xxx methods are used by the old verifier to
2671  * read entries in the constant pool.  Since the old verifier always
2672  * works on a copy of the code, it will not see any rewriting that
2673  * may possibly occur in the middle of verification.  So it is important
2674  * that nothing it calls tries to use the cpCache instead of the raw
2675  * constant pool, so we must use cp->uncached_x methods when appropriate.
2676  */
2677 JVM_ENTRY(const char*, JVM_GetCPFieldNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2678   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2679   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2680   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2681   switch (cp->tag_at(cp_index).value()) {
2682     case JVM_CONSTANT_Fieldref:
2683       return cp->uncached_name_ref_at(cp_index)->as_utf8();
2684     default:
2685       fatal("JVM_GetCPFieldNameUTF: illegal constant");
2686   }
2687   ShouldNotReachHere();
2688   return nullptr;
2689 JVM_END
2690 
2691 
2692 JVM_ENTRY(const char*, JVM_GetCPMethodNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2693   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2694   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2695   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2696   switch (cp->tag_at(cp_index).value()) {
2697     case JVM_CONSTANT_InterfaceMethodref:
2698     case JVM_CONSTANT_Methodref:
2699       return cp->uncached_name_ref_at(cp_index)->as_utf8();
2700     default:
2701       fatal("JVM_GetCPMethodNameUTF: illegal constant");
2702   }
2703   ShouldNotReachHere();
2704   return nullptr;
2705 JVM_END
2706 
2707 
2708 JVM_ENTRY(const char*, JVM_GetCPMethodSignatureUTF(JNIEnv *env, jclass cls, jint cp_index))
2709   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2710   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2711   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2712   switch (cp->tag_at(cp_index).value()) {
2713     case JVM_CONSTANT_InterfaceMethodref:
2714     case JVM_CONSTANT_Methodref:
2715       return cp->uncached_signature_ref_at(cp_index)->as_utf8();
2716     default:
2717       fatal("JVM_GetCPMethodSignatureUTF: illegal constant");
2718   }
2719   ShouldNotReachHere();
2720   return nullptr;
2721 JVM_END
2722 
2723 
2724 JVM_ENTRY(const char*, JVM_GetCPFieldSignatureUTF(JNIEnv *env, jclass cls, jint cp_index))
2725   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2726   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2727   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2728   switch (cp->tag_at(cp_index).value()) {
2729     case JVM_CONSTANT_Fieldref:
2730       return cp->uncached_signature_ref_at(cp_index)->as_utf8();
2731     default:
2732       fatal("JVM_GetCPFieldSignatureUTF: illegal constant");
2733   }
2734   ShouldNotReachHere();
2735   return nullptr;
2736 JVM_END
2737 
2738 
2739 JVM_ENTRY(const char*, JVM_GetCPClassNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2740   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2741   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2742   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2743   Symbol* classname = cp->klass_name_at(cp_index);
2744   return classname->as_utf8();
2745 JVM_END
2746 
2747 
2748 JVM_ENTRY(const char*, JVM_GetCPFieldClassNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2749   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2750   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2751   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2752   switch (cp->tag_at(cp_index).value()) {
2753     case JVM_CONSTANT_Fieldref: {
2754       int class_index = cp->uncached_klass_ref_index_at(cp_index);
2755       Symbol* classname = cp->klass_name_at(class_index);
2756       return classname->as_utf8();
2757     }
2758     default:
2759       fatal("JVM_GetCPFieldClassNameUTF: illegal constant");
2760   }
2761   ShouldNotReachHere();
2762   return nullptr;
2763 JVM_END
2764 
2765 
2766 JVM_ENTRY(const char*, JVM_GetCPMethodClassNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2767   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2768   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2769   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2770   switch (cp->tag_at(cp_index).value()) {
2771     case JVM_CONSTANT_Methodref:
2772     case JVM_CONSTANT_InterfaceMethodref: {
2773       int class_index = cp->uncached_klass_ref_index_at(cp_index);
2774       Symbol* classname = cp->klass_name_at(class_index);
2775       return classname->as_utf8();
2776     }
2777     default:
2778       fatal("JVM_GetCPMethodClassNameUTF: illegal constant");
2779   }
2780   ShouldNotReachHere();
2781   return nullptr;
2782 JVM_END
2783 
2784 
2785 JVM_ENTRY(jint, JVM_GetCPFieldModifiers(JNIEnv *env, jclass cls, int cp_index, jclass called_cls))
2786   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2787   Klass* k_called = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(called_cls));
2788   k        = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2789   k_called = JvmtiThreadState::class_to_verify_considering_redefinition(k_called, thread);
2790   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2791   ConstantPool* cp_called = InstanceKlass::cast(k_called)->constants();
2792   switch (cp->tag_at(cp_index).value()) {
2793     case JVM_CONSTANT_Fieldref: {
2794       Symbol* name      = cp->uncached_name_ref_at(cp_index);
2795       Symbol* signature = cp->uncached_signature_ref_at(cp_index);
2796       InstanceKlass* ik = InstanceKlass::cast(k_called);
2797       for (JavaFieldStream fs(ik); !fs.done(); fs.next()) {
2798         if (fs.name() == name && fs.signature() == signature) {
2799           return fs.access_flags().as_field_flags();
2800         }
2801       }
2802       return -1;
2803     }
2804     default:
2805       fatal("JVM_GetCPFieldModifiers: illegal constant");
2806   }
2807   ShouldNotReachHere();
2808   return 0;
2809 JVM_END
2810 
2811 
2812 JVM_ENTRY(jint, JVM_GetCPMethodModifiers(JNIEnv *env, jclass cls, int cp_index, jclass called_cls))
2813   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2814   Klass* k_called = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(called_cls));
2815   k        = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2816   k_called = JvmtiThreadState::class_to_verify_considering_redefinition(k_called, thread);
2817   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2818   switch (cp->tag_at(cp_index).value()) {
2819     case JVM_CONSTANT_Methodref:
2820     case JVM_CONSTANT_InterfaceMethodref: {
2821       Symbol* name      = cp->uncached_name_ref_at(cp_index);
2822       Symbol* signature = cp->uncached_signature_ref_at(cp_index);
2823       Array<Method*>* methods = InstanceKlass::cast(k_called)->methods();
2824       int methods_count = methods->length();
2825       for (int i = 0; i < methods_count; i++) {
2826         Method* method = methods->at(i);
2827         if (method->name() == name && method->signature() == signature) {
2828             return method->access_flags().as_method_flags();
2829         }
2830       }
2831       return -1;
2832     }
2833     default:
2834       fatal("JVM_GetCPMethodModifiers: illegal constant");
2835   }
2836   ShouldNotReachHere();
2837   return 0;
2838 JVM_END
2839 
2840 
2841 // Misc //////////////////////////////////////////////////////////////////////////////////////////////
2842 
2843 JVM_LEAF(void, JVM_ReleaseUTF(const char *utf))
2844   // So long as UTF8::convert_to_utf8 returns resource strings, we don't have to do anything
2845 JVM_END
2846 
2847 
2848 JVM_ENTRY(jboolean, JVM_IsSameClassPackage(JNIEnv *env, jclass class1, jclass class2))
2849   oop class1_mirror = JNIHandles::resolve_non_null(class1);
2850   oop class2_mirror = JNIHandles::resolve_non_null(class2);
2851   Klass* klass1 = java_lang_Class::as_Klass(class1_mirror);
2852   Klass* klass2 = java_lang_Class::as_Klass(class2_mirror);
2853   return (jboolean) Reflection::is_same_class_package(klass1, klass2);
2854 JVM_END
2855 
2856 // Printing support //////////////////////////////////////////////////
2857 extern "C" {
2858 
2859 ATTRIBUTE_PRINTF(3, 0)
2860 int jio_vsnprintf(char *str, size_t count, const char *fmt, va_list args) {
2861   // Reject count values that are negative signed values converted to
2862   // unsigned; see bug 4399518, 4417214
2863   if ((intptr_t)count <= 0) return -1;
2864 
2865   int result = os::vsnprintf(str, count, fmt, args);
2866   if (result > 0 && (size_t)result >= count) {
2867     result = -1;
2868   }
2869 
2870   return result;
2871 }
2872 
2873 ATTRIBUTE_PRINTF(3, 4)
2874 int jio_snprintf(char *str, size_t count, const char *fmt, ...) {
2875   va_list args;
2876   int len;
2877   va_start(args, fmt);
2878   len = jio_vsnprintf(str, count, fmt, args);
2879   va_end(args);
2880   return len;
2881 }
2882 
2883 ATTRIBUTE_PRINTF(2, 3)
2884 int jio_fprintf(FILE* f, const char *fmt, ...) {
2885   int len;
2886   va_list args;
2887   va_start(args, fmt);
2888   len = jio_vfprintf(f, fmt, args);
2889   va_end(args);
2890   return len;
2891 }
2892 
2893 ATTRIBUTE_PRINTF(2, 0)
2894 int jio_vfprintf(FILE* f, const char *fmt, va_list args) {
2895   if (Arguments::vfprintf_hook() != nullptr) {
2896      return Arguments::vfprintf_hook()(f, fmt, args);
2897   } else {
2898     return vfprintf(f, fmt, args);
2899   }
2900 }
2901 
2902 ATTRIBUTE_PRINTF(1, 2)
2903 JNIEXPORT int jio_printf(const char *fmt, ...) {
2904   int len;
2905   va_list args;
2906   va_start(args, fmt);
2907   len = jio_vfprintf(defaultStream::output_stream(), fmt, args);
2908   va_end(args);
2909   return len;
2910 }
2911 
2912 // HotSpot specific jio method
2913 void jio_print(const char* s, size_t len) {
2914   // Try to make this function as atomic as possible.
2915   if (Arguments::vfprintf_hook() != nullptr) {
2916     jio_fprintf(defaultStream::output_stream(), "%.*s", (int)len, s);
2917   } else {
2918     // Make an unused local variable to avoid warning from gcc compiler.
2919     bool dummy = os::write(defaultStream::output_fd(), s, len);
2920   }
2921 }
2922 
2923 } // Extern C
2924 
2925 // java.lang.Thread //////////////////////////////////////////////////////////////////////////////
2926 
2927 // In most of the JVM thread support functions we need to access the
2928 // thread through a ThreadsListHandle to prevent it from exiting and
2929 // being reclaimed while we try to operate on it. The exceptions to this
2930 // rule are when operating on the current thread, or if the monitor of
2931 // the target java.lang.Thread is locked at the Java level - in both
2932 // cases the target cannot exit.
2933 
2934 static void thread_entry(JavaThread* thread, TRAPS) {
2935   HandleMark hm(THREAD);
2936   Handle obj(THREAD, thread->threadObj());
2937   JavaValue result(T_VOID);
2938   JavaCalls::call_virtual(&result,
2939                           obj,
2940                           vmClasses::Thread_klass(),
2941                           vmSymbols::run_method_name(),
2942                           vmSymbols::void_method_signature(),
2943                           THREAD);
2944 }
2945 
2946 
2947 JVM_ENTRY(void, JVM_StartThread(JNIEnv* env, jobject jthread))
2948 #if INCLUDE_CDS
2949   if (CDSConfig::allow_only_single_java_thread()) {
2950     // During java -Xshare:dump, if we allow multiple Java threads to
2951     // execute in parallel, symbols and classes may be loaded in
2952     // random orders which will make the resulting CDS archive
2953     // non-deterministic.
2954     //
2955     // Lucikly, during java -Xshare:dump, it's important to run only
2956     // the code in the main Java thread (which is NOT started here) that
2957     // creates the module graph, etc. It's safe to not start the other
2958     // threads which are launched by class static initializers
2959     // (ReferenceHandler, FinalizerThread and CleanerImpl).
2960     if (log_is_enabled(Info, cds)) {
2961       ResourceMark rm;
2962       oop t = JNIHandles::resolve_non_null(jthread);
2963       log_info(cds)("JVM_StartThread() ignored: %s", t->klass()->external_name());
2964     }
2965     return;
2966   }
2967 #endif
2968   JavaThread *native_thread = nullptr;
2969 
2970   // We cannot hold the Threads_lock when we throw an exception,
2971   // due to rank ordering issues. Example:  we might need to grab the
2972   // Heap_lock while we construct the exception.
2973   bool throw_illegal_thread_state = false;
2974 
2975   // We must release the Threads_lock before we can post a jvmti event
2976   // in Thread::start.
2977   {
2978     ConditionalMutexLocker throttle_ml(ThreadsLockThrottle_lock, UseThreadsLockThrottleLock);
2979     // Ensure that the C++ Thread and OSThread structures aren't freed before
2980     // we operate.
2981     MutexLocker ml(Threads_lock);
2982 
2983     // Since JDK 5 the java.lang.Thread threadStatus is used to prevent
2984     // re-starting an already started thread, so we should usually find
2985     // that the JavaThread is null. However for a JNI attached thread
2986     // there is a small window between the Thread object being created
2987     // (with its JavaThread set) and the update to its threadStatus, so we
2988     // have to check for this
2989     if (java_lang_Thread::thread(JNIHandles::resolve_non_null(jthread)) != nullptr) {
2990       throw_illegal_thread_state = true;
2991     } else {
2992       jlong size =
2993              java_lang_Thread::stackSize(JNIHandles::resolve_non_null(jthread));
2994       // Allocate the C++ Thread structure and create the native thread.  The
2995       // stack size retrieved from java is 64-bit signed, but the constructor takes
2996       // size_t (an unsigned type), which may be 32 or 64-bit depending on the platform.
2997       //  - Avoid truncating on 32-bit platforms if size is greater than UINT_MAX.
2998       //  - Avoid passing negative values which would result in really large stacks.
2999       NOT_LP64(if (size > SIZE_MAX) size = SIZE_MAX;)
3000       size_t sz = size > 0 ? (size_t) size : 0;
3001       native_thread = new JavaThread(&thread_entry, sz);
3002 
3003       // At this point it may be possible that no osthread was created for the
3004       // JavaThread due to lack of memory. Check for this situation and throw
3005       // an exception if necessary. Eventually we may want to change this so
3006       // that we only grab the lock if the thread was created successfully -
3007       // then we can also do this check and throw the exception in the
3008       // JavaThread constructor.
3009       if (native_thread->osthread() != nullptr) {
3010         // Note: the current thread is not being used within "prepare".
3011         native_thread->prepare(jthread);
3012       }
3013     }
3014   }
3015 
3016   if (throw_illegal_thread_state) {
3017     THROW(vmSymbols::java_lang_IllegalThreadStateException());
3018   }
3019 
3020   assert(native_thread != nullptr, "Starting null thread?");
3021 
3022   if (native_thread->osthread() == nullptr) {
3023     ResourceMark rm(thread);
3024     log_warning(os, thread)("Failed to start the native thread for java.lang.Thread \"%s\"",
3025                             JavaThread::name_for(JNIHandles::resolve_non_null(jthread)));
3026     // No one should hold a reference to the 'native_thread'.
3027     native_thread->smr_delete();
3028     if (JvmtiExport::should_post_resource_exhausted()) {
3029       JvmtiExport::post_resource_exhausted(
3030         JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_THREADS,
3031         os::native_thread_creation_failed_msg());
3032     }
3033     THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(),
3034               os::native_thread_creation_failed_msg());
3035   }
3036 
3037   JFR_ONLY(Jfr::on_java_thread_start(thread, native_thread);)
3038 
3039   Thread::start(native_thread);
3040 
3041 JVM_END
3042 
3043 
3044 JVM_ENTRY(void, JVM_SetThreadPriority(JNIEnv* env, jobject jthread, jint prio))
3045   ThreadsListHandle tlh(thread);
3046   oop java_thread = nullptr;
3047   JavaThread* receiver = nullptr;
3048   bool is_alive = tlh.cv_internal_thread_to_JavaThread(jthread, &receiver, &java_thread);
3049   java_lang_Thread::set_priority(java_thread, (ThreadPriority)prio);
3050 
3051   if (is_alive) {
3052     // jthread refers to a live JavaThread.
3053     Thread::set_priority(receiver, (ThreadPriority)prio);
3054   }
3055   // Implied else: If the JavaThread hasn't started yet, then the
3056   // priority set in the java.lang.Thread object above will be pushed
3057   // down when it does start.
3058 JVM_END
3059 
3060 
3061 JVM_LEAF(void, JVM_Yield(JNIEnv *env, jclass threadClass))
3062   HOTSPOT_THREAD_YIELD();
3063   os::naked_yield();
3064 JVM_END
3065 
3066 JVM_ENTRY(void, JVM_SleepNanos(JNIEnv* env, jclass threadClass, jlong nanos))
3067   if (nanos < 0) {
3068     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nanosecond timeout value out of range");
3069   }
3070 
3071   if (thread->is_interrupted(true) && !HAS_PENDING_EXCEPTION) {
3072     THROW_MSG(vmSymbols::java_lang_InterruptedException(), "sleep interrupted");
3073   }
3074 
3075   // Save current thread state and restore it at the end of this block.
3076   // And set new thread state to SLEEPING.
3077   JavaThreadSleepState jtss(thread);
3078 
3079   HOTSPOT_THREAD_SLEEP_BEGIN(nanos / NANOSECS_PER_MILLISEC);
3080 
3081   if (nanos == 0) {
3082     os::naked_yield();
3083   } else {
3084     ThreadState old_state = thread->osthread()->get_state();
3085     thread->osthread()->set_state(SLEEPING);
3086     if (!thread->sleep_nanos(nanos)) { // interrupted
3087       // An asynchronous exception could have been thrown on
3088       // us while we were sleeping. We do not overwrite those.
3089       if (!HAS_PENDING_EXCEPTION) {
3090         HOTSPOT_THREAD_SLEEP_END(1);
3091 
3092         // TODO-FIXME: THROW_MSG returns which means we will not call set_state()
3093         // to properly restore the thread state.  That's likely wrong.
3094         THROW_MSG(vmSymbols::java_lang_InterruptedException(), "sleep interrupted");
3095       }
3096     }
3097     thread->osthread()->set_state(old_state);
3098   }
3099   HOTSPOT_THREAD_SLEEP_END(0);
3100 JVM_END
3101 
3102 JVM_ENTRY(jobject, JVM_CurrentCarrierThread(JNIEnv* env, jclass threadClass))
3103   oop jthread = thread->threadObj();
3104   assert(jthread != nullptr, "no current carrier thread!");
3105   return JNIHandles::make_local(THREAD, jthread);
3106 JVM_END
3107 
3108 JVM_ENTRY(jobject, JVM_CurrentThread(JNIEnv* env, jclass threadClass))
3109   oop theThread = thread->vthread();
3110   assert(theThread != (oop)nullptr, "no current thread!");
3111   return JNIHandles::make_local(THREAD, theThread);
3112 JVM_END
3113 
3114 JVM_ENTRY(void, JVM_SetCurrentThread(JNIEnv* env, jobject thisThread,
3115                                      jobject theThread))
3116   oop threadObj = JNIHandles::resolve(theThread);
3117   thread->set_vthread(threadObj);
3118 
3119   // Set _monitor_owner_id of new current Thread
3120   thread->set_monitor_owner_id(java_lang_Thread::thread_id(threadObj));
3121 
3122   JFR_ONLY(Jfr::on_set_current_thread(thread, threadObj);)
3123 JVM_END
3124 
3125 JVM_ENTRY(jlong, JVM_GetNextThreadIdOffset(JNIEnv* env, jclass threadClass))
3126   return ThreadIdentifier::unsafe_offset();
3127 JVM_END
3128 
3129 JVM_ENTRY(void, JVM_Interrupt(JNIEnv* env, jobject jthread))
3130   ThreadsListHandle tlh(thread);
3131   JavaThread* receiver = nullptr;
3132   bool is_alive = tlh.cv_internal_thread_to_JavaThread(jthread, &receiver, nullptr);
3133   if (is_alive) {
3134     // jthread refers to a live JavaThread.
3135     receiver->interrupt();
3136   }
3137 JVM_END
3138 
3139 // Return true iff the current thread has locked the object passed in
3140 
3141 JVM_ENTRY(jboolean, JVM_HoldsLock(JNIEnv* env, jclass threadClass, jobject obj))
3142   if (obj == nullptr) {
3143     THROW_(vmSymbols::java_lang_NullPointerException(), JNI_FALSE);
3144   }
3145   Handle h_obj(THREAD, JNIHandles::resolve(obj));
3146   return ObjectSynchronizer::current_thread_holds_lock(thread, h_obj);
3147 JVM_END
3148 
3149 JVM_ENTRY(jobject, JVM_GetStackTrace(JNIEnv *env, jobject jthread))
3150   oop trace = java_lang_Thread::async_get_stack_trace(JNIHandles::resolve(jthread), THREAD);
3151   return JNIHandles::make_local(THREAD, trace);
3152 JVM_END
3153 
3154 JVM_ENTRY(void, JVM_SetNativeThreadName(JNIEnv* env, jobject jthread, jstring name))
3155   // We don't use a ThreadsListHandle here because the current thread
3156   // must be alive.
3157   oop java_thread = JNIHandles::resolve_non_null(jthread);
3158   JavaThread* thr = java_lang_Thread::thread(java_thread);
3159   if (thread == thr && !thr->has_attached_via_jni()) {
3160     // Thread naming is only supported for the current thread and
3161     // we don't set the name of an attached thread to avoid stepping
3162     // on other programs.
3163     ResourceMark rm(thread);
3164     const char *thread_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
3165     os::set_native_thread_name(thread_name);
3166   }
3167 JVM_END
3168 
3169 JVM_ENTRY(jobject, JVM_ScopedValueCache(JNIEnv* env, jclass threadClass))
3170   oop theCache = thread->scopedValueCache();
3171   return JNIHandles::make_local(THREAD, theCache);
3172 JVM_END
3173 
3174 JVM_ENTRY(void, JVM_SetScopedValueCache(JNIEnv* env, jclass threadClass,
3175                                        jobject theCache))
3176   arrayOop objs = arrayOop(JNIHandles::resolve(theCache));
3177   thread->set_scopedValueCache(objs);
3178 JVM_END
3179 
3180 
3181 // java.lang.Package ////////////////////////////////////////////////////////////////
3182 
3183 
3184 JVM_ENTRY(jstring, JVM_GetSystemPackage(JNIEnv *env, jstring name))
3185   ResourceMark rm(THREAD);
3186   JvmtiVMObjectAllocEventCollector oam;
3187   char* str = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
3188   oop result = ClassLoader::get_system_package(str, CHECK_NULL);
3189 return (jstring) JNIHandles::make_local(THREAD, result);
3190 JVM_END
3191 
3192 
3193 JVM_ENTRY(jobjectArray, JVM_GetSystemPackages(JNIEnv *env))
3194   JvmtiVMObjectAllocEventCollector oam;
3195   objArrayOop result = ClassLoader::get_system_packages(CHECK_NULL);
3196   return (jobjectArray) JNIHandles::make_local(THREAD, result);
3197 JVM_END
3198 
3199 
3200 // java.lang.ref.Reference ///////////////////////////////////////////////////////////////
3201 
3202 
3203 JVM_ENTRY(jobject, JVM_GetAndClearReferencePendingList(JNIEnv* env))
3204   MonitorLocker ml(Heap_lock);
3205   oop ref = Universe::reference_pending_list();
3206   if (ref != nullptr) {
3207     Universe::clear_reference_pending_list();
3208   }
3209   return JNIHandles::make_local(THREAD, ref);
3210 JVM_END
3211 
3212 JVM_ENTRY(jboolean, JVM_HasReferencePendingList(JNIEnv* env))
3213   MonitorLocker ml(Heap_lock);
3214   return Universe::has_reference_pending_list();
3215 JVM_END
3216 
3217 JVM_ENTRY(void, JVM_WaitForReferencePendingList(JNIEnv* env))
3218   MonitorLocker ml(Heap_lock);
3219   while (!Universe::has_reference_pending_list()) {
3220     ml.wait();
3221   }
3222 JVM_END
3223 
3224 JVM_ENTRY(jboolean, JVM_ReferenceRefersTo(JNIEnv* env, jobject ref, jobject o))
3225   oop ref_oop = JNIHandles::resolve_non_null(ref);
3226   // PhantomReference has it's own implementation of refersTo().
3227   // See: JVM_PhantomReferenceRefersTo
3228   assert(!java_lang_ref_Reference::is_phantom(ref_oop), "precondition");
3229   oop referent = java_lang_ref_Reference::weak_referent_no_keepalive(ref_oop);
3230   return referent == JNIHandles::resolve(o);
3231 JVM_END
3232 
3233 JVM_ENTRY(void, JVM_ReferenceClear(JNIEnv* env, jobject ref))
3234   oop ref_oop = JNIHandles::resolve_non_null(ref);
3235   // FinalReference has it's own implementation of clear().
3236   assert(!java_lang_ref_Reference::is_final(ref_oop), "precondition");
3237   if (java_lang_ref_Reference::unknown_referent_no_keepalive(ref_oop) == nullptr) {
3238     // If the referent has already been cleared then done.
3239     // However, if the referent is dead but has not yet been cleared by
3240     // concurrent reference processing, it should NOT be cleared here.
3241     // Instead, clearing should be left to the GC.  Clearing it here could
3242     // detectably lose an expected notification, which is impossible with
3243     // STW reference processing.  The clearing in enqueue() doesn't have
3244     // this problem, since the enqueue covers the notification, but it's not
3245     // worth the effort to handle that case specially.
3246     return;
3247   }
3248   java_lang_ref_Reference::clear_referent(ref_oop);
3249 JVM_END
3250 
3251 
3252 // java.lang.ref.PhantomReference //////////////////////////////////////////////////
3253 
3254 
3255 JVM_ENTRY(jboolean, JVM_PhantomReferenceRefersTo(JNIEnv* env, jobject ref, jobject o))
3256   oop ref_oop = JNIHandles::resolve_non_null(ref);
3257   oop referent = java_lang_ref_Reference::phantom_referent_no_keepalive(ref_oop);
3258   return referent == JNIHandles::resolve(o);
3259 JVM_END
3260 
3261 
3262 // ObjectInputStream ///////////////////////////////////////////////////////////////
3263 
3264 // Return the first user-defined class loader up the execution stack, or null
3265 // if only code from the bootstrap or platform class loader is on the stack.
3266 
3267 JVM_ENTRY(jobject, JVM_LatestUserDefinedLoader(JNIEnv *env))
3268   for (vframeStream vfst(thread); !vfst.at_end(); vfst.next()) {
3269     InstanceKlass* ik = vfst.method()->method_holder();
3270     oop loader = ik->class_loader();
3271     if (loader != nullptr && !SystemDictionary::is_platform_class_loader(loader)) {
3272       return JNIHandles::make_local(THREAD, loader);
3273     }
3274   }
3275   return nullptr;
3276 JVM_END
3277 
3278 
3279 // Array ///////////////////////////////////////////////////////////////////////////////////////////
3280 
3281 
3282 // resolve array handle and check arguments
3283 static inline arrayOop check_array(JNIEnv *env, jobject arr, bool type_array_only, TRAPS) {
3284   if (arr == nullptr) {
3285     THROW_NULL(vmSymbols::java_lang_NullPointerException());
3286   }
3287   oop a = JNIHandles::resolve_non_null(arr);
3288   if (!a->is_array()) {
3289     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Argument is not an array");
3290   } else if (type_array_only && !a->is_typeArray()) {
3291     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Argument is not an array of primitive type");
3292   }
3293   return arrayOop(a);
3294 }
3295 
3296 
3297 JVM_ENTRY(jint, JVM_GetArrayLength(JNIEnv *env, jobject arr))
3298   arrayOop a = check_array(env, arr, false, CHECK_0);
3299   return a->length();
3300 JVM_END
3301 
3302 
3303 JVM_ENTRY(jobject, JVM_GetArrayElement(JNIEnv *env, jobject arr, jint index))
3304   JvmtiVMObjectAllocEventCollector oam;
3305   arrayOop a = check_array(env, arr, false, CHECK_NULL);
3306   jvalue value;
3307   BasicType type = Reflection::array_get(&value, a, index, CHECK_NULL);
3308   oop box = Reflection::box(&value, type, CHECK_NULL);
3309   return JNIHandles::make_local(THREAD, box);
3310 JVM_END
3311 
3312 
3313 JVM_ENTRY(jvalue, JVM_GetPrimitiveArrayElement(JNIEnv *env, jobject arr, jint index, jint wCode))
3314   jvalue value;
3315   value.i = 0; // to initialize value before getting used in CHECK
3316   arrayOop a = check_array(env, arr, true, CHECK_(value));
3317   assert(a->is_typeArray(), "just checking");
3318   BasicType type = Reflection::array_get(&value, a, index, CHECK_(value));
3319   BasicType wide_type = (BasicType) wCode;
3320   if (type != wide_type) {
3321     Reflection::widen(&value, type, wide_type, CHECK_(value));
3322   }
3323   return value;
3324 JVM_END
3325 
3326 
3327 JVM_ENTRY(void, JVM_SetArrayElement(JNIEnv *env, jobject arr, jint index, jobject val))
3328   arrayOop a = check_array(env, arr, false, CHECK);
3329   oop box = JNIHandles::resolve(val);
3330   jvalue value;
3331   value.i = 0; // to initialize value before getting used in CHECK
3332   BasicType value_type;
3333   if (a->is_objArray()) {
3334     // Make sure we do no unbox e.g. java/lang/Integer instances when storing into an object array
3335     value_type = Reflection::unbox_for_regular_object(box, &value);
3336   } else {
3337     value_type = Reflection::unbox_for_primitive(box, &value, CHECK);
3338   }
3339   Reflection::array_set(&value, a, index, value_type, CHECK);
3340 JVM_END
3341 
3342 
3343 JVM_ENTRY(void, JVM_SetPrimitiveArrayElement(JNIEnv *env, jobject arr, jint index, jvalue v, unsigned char vCode))
3344   arrayOop a = check_array(env, arr, true, CHECK);
3345   assert(a->is_typeArray(), "just checking");
3346   BasicType value_type = (BasicType) vCode;
3347   Reflection::array_set(&v, a, index, value_type, CHECK);
3348 JVM_END
3349 
3350 
3351 JVM_ENTRY(jobject, JVM_NewArray(JNIEnv *env, jclass eltClass, jint length))
3352   JvmtiVMObjectAllocEventCollector oam;
3353   oop element_mirror = JNIHandles::resolve(eltClass);
3354   oop result = Reflection::reflect_new_array(element_mirror, length, CHECK_NULL);
3355   return JNIHandles::make_local(THREAD, result);
3356 JVM_END
3357 
3358 
3359 JVM_ENTRY(jobject, JVM_NewMultiArray(JNIEnv *env, jclass eltClass, jintArray dim))
3360   JvmtiVMObjectAllocEventCollector oam;
3361   arrayOop dim_array = check_array(env, dim, true, CHECK_NULL);
3362   oop element_mirror = JNIHandles::resolve(eltClass);
3363   assert(dim_array->is_typeArray(), "just checking");
3364   oop result = Reflection::reflect_new_multi_array(element_mirror, typeArrayOop(dim_array), CHECK_NULL);
3365   return JNIHandles::make_local(THREAD, result);
3366 JVM_END
3367 
3368 
3369 // Library support ///////////////////////////////////////////////////////////////////////////
3370 
3371 JVM_LEAF(void*, JVM_LoadZipLibrary())
3372   return ZipLibrary::handle();
3373 JVM_END
3374 
3375 JVM_ENTRY_NO_ENV(void*, JVM_LoadLibrary(const char* name, jboolean throwException))
3376   //%note jvm_ct
3377   char ebuf[1024];
3378   void *load_result;
3379   {
3380     ThreadToNativeFromVM ttnfvm(thread);
3381     load_result = os::dll_load(name, ebuf, sizeof ebuf);
3382   }
3383   if (load_result == nullptr) {
3384     if (throwException) {
3385       char msg[1024];
3386       jio_snprintf(msg, sizeof msg, "%s: %s", name, ebuf);
3387       // Since 'ebuf' may contain a string encoded using
3388       // platform encoding scheme, we need to pass
3389       // Exceptions::unsafe_to_utf8 to the new_exception method
3390       // as the last argument. See bug 6367357.
3391       Handle h_exception =
3392         Exceptions::new_exception(thread,
3393                                   vmSymbols::java_lang_UnsatisfiedLinkError(),
3394                                   msg, Exceptions::unsafe_to_utf8);
3395 
3396       THROW_HANDLE_NULL(h_exception);
3397     } else {
3398       log_info(library)("Failed to load library %s", name);
3399       return load_result;
3400     }
3401   }
3402   log_info(library)("Loaded library %s, handle " INTPTR_FORMAT, name, p2i(load_result));
3403   return load_result;
3404 JVM_END
3405 
3406 
3407 JVM_LEAF(void, JVM_UnloadLibrary(void* handle))
3408   os::dll_unload(handle);
3409   log_info(library)("Unloaded library with handle " INTPTR_FORMAT, p2i(handle));
3410 JVM_END
3411 
3412 
3413 JVM_LEAF(void*, JVM_FindLibraryEntry(void* handle, const char* name))
3414   void* find_result = os::dll_lookup(handle, name);
3415   log_info(library)("%s %s in library with handle " INTPTR_FORMAT,
3416                     find_result != nullptr ? "Found" : "Failed to find",
3417                     name, p2i(handle));
3418   return find_result;
3419 JVM_END
3420 
3421 
3422 // JNI version ///////////////////////////////////////////////////////////////////////////////
3423 
3424 JVM_LEAF(jboolean, JVM_IsSupportedJNIVersion(jint version))
3425   return Threads::is_supported_jni_version_including_1_1(version);
3426 JVM_END
3427 
3428 
3429 JVM_LEAF(jboolean, JVM_IsPreviewEnabled(void))
3430   return Arguments::enable_preview() ? JNI_TRUE : JNI_FALSE;
3431 JVM_END
3432 
3433 JVM_LEAF(jboolean, JVM_IsValhallaEnabled(void))
3434   return EnableValhalla ? JNI_TRUE : JNI_FALSE;
3435 JVM_END
3436 
3437 JVM_LEAF(jboolean, JVM_IsContinuationsSupported(void))
3438   return VMContinuations ? JNI_TRUE : JNI_FALSE;
3439 JVM_END
3440 
3441 JVM_LEAF(jboolean, JVM_IsForeignLinkerSupported(void))
3442   return ForeignGlobals::is_foreign_linker_supported() ? JNI_TRUE : JNI_FALSE;
3443 JVM_END
3444 
3445 JVM_LEAF(jboolean, JVM_IsStaticallyLinked(void))
3446   return is_vm_statically_linked() ? JNI_TRUE : JNI_FALSE;
3447 JVM_END
3448 
3449 // String support ///////////////////////////////////////////////////////////////////////////
3450 
3451 JVM_ENTRY(jstring, JVM_InternString(JNIEnv *env, jstring str))
3452   JvmtiVMObjectAllocEventCollector oam;
3453   if (str == nullptr) return nullptr;
3454   oop string = JNIHandles::resolve_non_null(str);
3455   oop result = StringTable::intern(string, CHECK_NULL);
3456   return (jstring) JNIHandles::make_local(THREAD, result);
3457 JVM_END
3458 
3459 
3460 // VM Raw monitor support //////////////////////////////////////////////////////////////////////
3461 
3462 // VM Raw monitors (not to be confused with JvmtiRawMonitors) are a simple mutual exclusion
3463 // lock (not actually monitors: no wait/notify) that is exported by the VM for use by JDK
3464 // library code. They may be used by JavaThreads and non-JavaThreads and do not participate
3465 // in the safepoint protocol, thread suspension, thread interruption, or most things of that
3466 // nature, except JavaThreads will be blocked by VM_Exit::block_if_vm_exited if the VM has
3467 // shutdown. JavaThreads will be "in native" when using this API from JDK code.
3468 
3469 
3470 JNIEXPORT void* JNICALL JVM_RawMonitorCreate(void) {
3471   VM_Exit::block_if_vm_exited();
3472   return new PlatformMutex();
3473 }
3474 
3475 
3476 JNIEXPORT void JNICALL  JVM_RawMonitorDestroy(void *mon) {
3477   VM_Exit::block_if_vm_exited();
3478   delete ((PlatformMutex*) mon);
3479 }
3480 
3481 
3482 JNIEXPORT jint JNICALL JVM_RawMonitorEnter(void *mon) {
3483   VM_Exit::block_if_vm_exited();
3484   ((PlatformMutex*) mon)->lock();
3485   return 0;
3486 }
3487 
3488 
3489 JNIEXPORT void JNICALL JVM_RawMonitorExit(void *mon) {
3490   VM_Exit::block_if_vm_exited();
3491   ((PlatformMutex*) mon)->unlock();
3492 }
3493 
3494 
3495 // Shared JNI/JVM entry points //////////////////////////////////////////////////////////////
3496 
3497 jclass find_class_from_class_loader(JNIEnv* env, Symbol* name, jboolean init,
3498                                     Handle loader, jboolean throwError, TRAPS) {
3499   Klass* klass = SystemDictionary::resolve_or_fail(name, loader, throwError != 0, CHECK_NULL);
3500 
3501   // Check if we should initialize the class
3502   if (init && klass->is_instance_klass()) {
3503     klass->initialize(CHECK_NULL);
3504   }
3505   return (jclass) JNIHandles::make_local(THREAD, klass->java_mirror());
3506 }
3507 
3508 
3509 // Method ///////////////////////////////////////////////////////////////////////////////////////////
3510 
3511 JVM_ENTRY(jobject, JVM_InvokeMethod(JNIEnv *env, jobject method, jobject obj, jobjectArray args0))
3512   Handle method_handle;
3513   if (thread->stack_overflow_state()->stack_available((address) &method_handle) >= JVMInvokeMethodSlack) {
3514     method_handle = Handle(THREAD, JNIHandles::resolve(method));
3515     Handle receiver(THREAD, JNIHandles::resolve(obj));
3516     objArrayHandle args(THREAD, (objArrayOop)JNIHandles::resolve(args0));
3517     assert(args() == nullptr || !args->is_flatArray(), "args are never flat or are they???");
3518 
3519     oop result = Reflection::invoke_method(method_handle(), receiver, args, CHECK_NULL);
3520     jobject res = JNIHandles::make_local(THREAD, result);
3521     if (JvmtiExport::should_post_vm_object_alloc()) {
3522       oop ret_type = java_lang_reflect_Method::return_type(method_handle());
3523       assert(ret_type != nullptr, "sanity check: ret_type oop must not be null!");
3524       if (java_lang_Class::is_primitive(ret_type)) {
3525         // Only for primitive type vm allocates memory for java object.
3526         // See box() method.
3527         JvmtiExport::post_vm_object_alloc(thread, result);
3528       }
3529     }
3530     return res;
3531   } else {
3532     THROW_NULL(vmSymbols::java_lang_StackOverflowError());
3533   }
3534 JVM_END
3535 
3536 
3537 JVM_ENTRY(jobject, JVM_NewInstanceFromConstructor(JNIEnv *env, jobject c, jobjectArray args0))
3538   objArrayHandle args(THREAD, (objArrayOop)JNIHandles::resolve(args0));
3539   assert(args() == nullptr || !args->is_flatArray(), "args are never flat or are they???");
3540   oop constructor_mirror = JNIHandles::resolve(c);
3541   oop result = Reflection::invoke_constructor(constructor_mirror, args, CHECK_NULL);
3542   jobject res = JNIHandles::make_local(THREAD, result);
3543   if (JvmtiExport::should_post_vm_object_alloc()) {
3544     JvmtiExport::post_vm_object_alloc(thread, result);
3545   }
3546   return res;
3547 JVM_END
3548 
3549 JVM_ENTRY(void, JVM_InitializeFromArchive(JNIEnv* env, jclass cls))
3550   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve(cls));
3551   HeapShared::initialize_from_archived_subgraph(THREAD, k);
3552 JVM_END
3553 
3554 JVM_ENTRY(void, JVM_RegisterLambdaProxyClassForArchiving(JNIEnv* env,
3555                                               jclass caller,
3556                                               jstring interfaceMethodName,
3557                                               jobject factoryType,
3558                                               jobject interfaceMethodType,
3559                                               jobject implementationMember,
3560                                               jobject dynamicMethodType,
3561                                               jclass lambdaProxyClass))
3562 #if INCLUDE_CDS
3563   if (!CDSConfig::is_dumping_archive() || !CDSConfig::is_dumping_lambdas_in_legacy_mode()) {
3564     return;
3565   }
3566 
3567   Klass* caller_k = java_lang_Class::as_Klass(JNIHandles::resolve(caller));
3568   InstanceKlass* caller_ik = InstanceKlass::cast(caller_k);
3569   if (caller_ik->is_hidden()) {
3570     // Hidden classes not of type lambda proxy classes are currently not being archived.
3571     // If the caller_ik is of one of the above types, the corresponding lambda proxy class won't be
3572     // registered for archiving.
3573     return;
3574   }
3575   Klass* lambda_k = java_lang_Class::as_Klass(JNIHandles::resolve(lambdaProxyClass));
3576   InstanceKlass* lambda_ik = InstanceKlass::cast(lambda_k);
3577   assert(lambda_ik->is_hidden(), "must be a hidden class");
3578   assert(!lambda_ik->is_non_strong_hidden(), "expected a strong hidden class");
3579 
3580   Symbol* interface_method_name = nullptr;
3581   if (interfaceMethodName != nullptr) {
3582     interface_method_name = java_lang_String::as_symbol(JNIHandles::resolve_non_null(interfaceMethodName));
3583   }
3584   Handle factory_type_oop(THREAD, JNIHandles::resolve_non_null(factoryType));
3585   Symbol* factory_type = java_lang_invoke_MethodType::as_signature(factory_type_oop(), true);
3586 
3587   Handle interface_method_type_oop(THREAD, JNIHandles::resolve_non_null(interfaceMethodType));
3588   Symbol* interface_method_type = java_lang_invoke_MethodType::as_signature(interface_method_type_oop(), true);
3589 
3590   Handle implementation_member_oop(THREAD, JNIHandles::resolve_non_null(implementationMember));
3591   assert(java_lang_invoke_MemberName::is_method(implementation_member_oop()), "must be");
3592   Method* m = java_lang_invoke_MemberName::vmtarget(implementation_member_oop());
3593 
3594   Handle dynamic_method_type_oop(THREAD, JNIHandles::resolve_non_null(dynamicMethodType));
3595   Symbol* dynamic_method_type = java_lang_invoke_MethodType::as_signature(dynamic_method_type_oop(), true);
3596 
3597   LambdaProxyClassDictionary::add_lambda_proxy_class(caller_ik, lambda_ik, interface_method_name, factory_type,
3598                                                      interface_method_type, m, dynamic_method_type, THREAD);
3599 #endif // INCLUDE_CDS
3600 JVM_END
3601 
3602 JVM_ENTRY(jclass, JVM_LookupLambdaProxyClassFromArchive(JNIEnv* env,
3603                                                         jclass caller,
3604                                                         jstring interfaceMethodName,
3605                                                         jobject factoryType,
3606                                                         jobject interfaceMethodType,
3607                                                         jobject implementationMember,
3608                                                         jobject dynamicMethodType))
3609 #if INCLUDE_CDS
3610 
3611   if (interfaceMethodName == nullptr || factoryType == nullptr || interfaceMethodType == nullptr ||
3612       implementationMember == nullptr || dynamicMethodType == nullptr) {
3613     THROW_(vmSymbols::java_lang_NullPointerException(), nullptr);
3614   }
3615 
3616   Klass* caller_k = java_lang_Class::as_Klass(JNIHandles::resolve(caller));
3617   InstanceKlass* caller_ik = InstanceKlass::cast(caller_k);
3618   if (!caller_ik->is_shared()) {
3619     // there won't be a shared lambda class if the caller_ik is not in the shared archive.
3620     return nullptr;
3621   }
3622 
3623   Symbol* interface_method_name = java_lang_String::as_symbol(JNIHandles::resolve_non_null(interfaceMethodName));
3624   Handle factory_type_oop(THREAD, JNIHandles::resolve_non_null(factoryType));
3625   Symbol* factory_type = java_lang_invoke_MethodType::as_signature(factory_type_oop(), true);
3626 
3627   Handle interface_method_type_oop(THREAD, JNIHandles::resolve_non_null(interfaceMethodType));
3628   Symbol* interface_method_type = java_lang_invoke_MethodType::as_signature(interface_method_type_oop(), true);
3629 
3630   Handle implementation_member_oop(THREAD, JNIHandles::resolve_non_null(implementationMember));
3631   assert(java_lang_invoke_MemberName::is_method(implementation_member_oop()), "must be");
3632   Method* m = java_lang_invoke_MemberName::vmtarget(implementation_member_oop());
3633 
3634   Handle dynamic_method_type_oop(THREAD, JNIHandles::resolve_non_null(dynamicMethodType));
3635   Symbol* dynamic_method_type = java_lang_invoke_MethodType::as_signature(dynamic_method_type_oop(), true);
3636 
3637   InstanceKlass* loaded_lambda =
3638     LambdaProxyClassDictionary::load_shared_lambda_proxy_class(caller_ik, interface_method_name, factory_type,
3639                                                                interface_method_type, m, dynamic_method_type,
3640                                                                CHECK_(nullptr));
3641   return loaded_lambda == nullptr ? nullptr : (jclass) JNIHandles::make_local(THREAD, loaded_lambda->java_mirror());
3642 #else
3643   return nullptr;
3644 #endif // INCLUDE_CDS
3645 JVM_END
3646 
3647 JVM_ENTRY_NO_ENV(jlong, JVM_GetRandomSeedForDumping())
3648   if (CDSConfig::is_dumping_static_archive()) {
3649     // We do this so that the default CDS archive can be deterministic.
3650     const char* release = VM_Version::vm_release();
3651     const char* dbg_level = VM_Version::jdk_debug_level();
3652     const char* version = VM_Version::internal_vm_info_string();
3653     jlong seed = (jlong)(java_lang_String::hash_code((const jbyte*)release, (int)strlen(release)) ^
3654                          java_lang_String::hash_code((const jbyte*)dbg_level, (int)strlen(dbg_level)) ^
3655                          java_lang_String::hash_code((const jbyte*)version, (int)strlen(version)));
3656     seed += (jlong)VM_Version::vm_major_version();
3657     seed += (jlong)VM_Version::vm_minor_version();
3658     seed += (jlong)VM_Version::vm_security_version();
3659     seed += (jlong)VM_Version::vm_patch_version();
3660     if (seed == 0) { // don't let this ever be zero.
3661       seed = 0x87654321;
3662     }
3663     log_debug(cds)("JVM_GetRandomSeedForDumping() = " JLONG_FORMAT, seed);
3664     return seed;
3665   } else {
3666     return 0;
3667   }
3668 JVM_END
3669 
3670 JVM_ENTRY_NO_ENV(jint, JVM_GetCDSConfigStatus())
3671   return CDSConfig::get_status();
3672 JVM_END
3673 
3674 JVM_ENTRY(void, JVM_LogLambdaFormInvoker(JNIEnv *env, jstring line))
3675 #if INCLUDE_CDS
3676   assert(CDSConfig::is_logging_lambda_form_invokers(), "sanity");
3677   if (line != nullptr) {
3678     ResourceMark rm(THREAD);
3679     Handle h_line (THREAD, JNIHandles::resolve_non_null(line));
3680     char* c_line = java_lang_String::as_utf8_string(h_line());
3681     if (CDSConfig::is_dumping_dynamic_archive()) {
3682       // Note: LambdaFormInvokers::append take same format which is not
3683       // same as below the print format. The line does not include LAMBDA_FORM_TAG.
3684       LambdaFormInvokers::append(os::strdup((const char*)c_line, mtInternal));
3685     }
3686     if (ClassListWriter::is_enabled()) {
3687       ClassListWriter w;
3688       w.stream()->print_cr("%s %s", ClassListParser::lambda_form_tag(), c_line);
3689     }
3690   }
3691 #endif // INCLUDE_CDS
3692 JVM_END
3693 
3694 JVM_ENTRY(void, JVM_DumpClassListToFile(JNIEnv *env, jstring listFileName))
3695 #if INCLUDE_CDS
3696   ResourceMark rm(THREAD);
3697   Handle file_handle(THREAD, JNIHandles::resolve_non_null(listFileName));
3698   char* file_name  = java_lang_String::as_utf8_string(file_handle());
3699   MetaspaceShared::dump_loaded_classes(file_name, THREAD);
3700 #endif // INCLUDE_CDS
3701 JVM_END
3702 
3703 JVM_ENTRY(void, JVM_DumpDynamicArchive(JNIEnv *env, jstring archiveName))
3704 #if INCLUDE_CDS
3705   ResourceMark rm(THREAD);
3706   Handle file_handle(THREAD, JNIHandles::resolve_non_null(archiveName));
3707   char* archive_name  = java_lang_String::as_utf8_string(file_handle());
3708   DynamicArchive::dump_for_jcmd(archive_name, CHECK);
3709 #endif // INCLUDE_CDS
3710 JVM_END
3711 
3712 JVM_ENTRY(jboolean, JVM_NeedsClassInitBarrierForCDS(JNIEnv* env, jclass cls))
3713 #if INCLUDE_CDS
3714   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve(cls));
3715   if (!k->is_instance_klass()) {
3716     return false;
3717   } else {
3718     if (InstanceKlass::cast(k)->is_enum_subclass() ||
3719         AOTClassInitializer::can_archive_initialized_mirror(InstanceKlass::cast(k))) {
3720       // This class will be cached in AOT-initialized state. No need for init barriers.
3721       return false;
3722     } else {
3723       // If we cannot cache the class in AOT-initialized state, java.lang.invoke handles
3724       // must emit barriers to ensure class initialization during production run.
3725       ResourceMark rm(THREAD);
3726       log_debug(cds)("NeedsClassInitBarrierForCDS: %s", k->external_name());
3727       return true;
3728     }
3729   }
3730 #else
3731   return false;
3732 #endif // INCLUDE_CDS
3733 JVM_END
3734 
3735 // Returns an array of all live Thread objects (VM internal JavaThreads,
3736 // jvmti agent threads, and JNI attaching threads  are skipped)
3737 // See CR 6404306 regarding JNI attaching threads
3738 JVM_ENTRY(jobjectArray, JVM_GetAllThreads(JNIEnv *env, jclass dummy))
3739   ResourceMark rm(THREAD);
3740   ThreadsListEnumerator tle(THREAD, false, false);
3741   JvmtiVMObjectAllocEventCollector oam;
3742 
3743   int num_threads = tle.num_threads();
3744   objArrayOop r = oopFactory::new_objArray(vmClasses::Thread_klass(), num_threads, CHECK_NULL);
3745   objArrayHandle threads_ah(THREAD, r);
3746 
3747   for (int i = 0; i < num_threads; i++) {
3748     Handle h = tle.get_threadObj(i);
3749     threads_ah->obj_at_put(i, h());
3750   }
3751 
3752   return (jobjectArray) JNIHandles::make_local(THREAD, threads_ah());
3753 JVM_END
3754 
3755 
3756 // Support for java.lang.Thread.getStackTrace() and getAllStackTraces() methods
3757 // Return StackTraceElement[][], each element is the stack trace of a thread in
3758 // the corresponding entry in the given threads array
3759 JVM_ENTRY(jobjectArray, JVM_DumpThreads(JNIEnv *env, jclass threadClass, jobjectArray threads))
3760   JvmtiVMObjectAllocEventCollector oam;
3761 
3762   // Check if threads is null
3763   if (threads == nullptr) {
3764     THROW_NULL(vmSymbols::java_lang_NullPointerException());
3765   }
3766 
3767   objArrayOop a = objArrayOop(JNIHandles::resolve_non_null(threads));
3768   objArrayHandle ah(THREAD, a);
3769   int num_threads = ah->length();
3770   // check if threads is non-empty array
3771   if (num_threads == 0) {
3772     THROW_NULL(vmSymbols::java_lang_IllegalArgumentException());
3773   }
3774 
3775   // check if threads is not an array of objects of Thread class
3776   Klass* k = ObjArrayKlass::cast(ah->klass())->element_klass();
3777   if (k != vmClasses::Thread_klass()) {
3778     THROW_NULL(vmSymbols::java_lang_IllegalArgumentException());
3779   }
3780 
3781   ResourceMark rm(THREAD);
3782 
3783   GrowableArray<instanceHandle>* thread_handle_array = new GrowableArray<instanceHandle>(num_threads);
3784   for (int i = 0; i < num_threads; i++) {
3785     oop thread_obj = ah->obj_at(i);
3786     instanceHandle h(THREAD, (instanceOop) thread_obj);
3787     thread_handle_array->append(h);
3788   }
3789 
3790   // The JavaThread references in thread_handle_array are validated
3791   // in VM_ThreadDump::doit().
3792   Handle stacktraces = ThreadService::dump_stack_traces(thread_handle_array, num_threads, CHECK_NULL);
3793   return (jobjectArray)JNIHandles::make_local(THREAD, stacktraces());
3794 
3795 JVM_END
3796 
3797 // JVM monitoring and management support
3798 JVM_LEAF(void*, JVM_GetManagement(jint version))
3799   return Management::get_jmm_interface(version);
3800 JVM_END
3801 
3802 // com.sun.tools.attach.VirtualMachine agent properties support
3803 //
3804 // Initialize the agent properties with the properties maintained in the VM
3805 JVM_ENTRY(jobject, JVM_InitAgentProperties(JNIEnv *env, jobject properties))
3806   ResourceMark rm;
3807 
3808   Handle props(THREAD, JNIHandles::resolve_non_null(properties));
3809 
3810   PUTPROP(props, "sun.java.command", Arguments::java_command());
3811   PUTPROP(props, "sun.jvm.flags", Arguments::jvm_flags());
3812   PUTPROP(props, "sun.jvm.args", Arguments::jvm_args());
3813   return properties;
3814 JVM_END
3815 
3816 JVM_ENTRY(jobjectArray, JVM_GetEnclosingMethodInfo(JNIEnv *env, jclass ofClass))
3817 {
3818   JvmtiVMObjectAllocEventCollector oam;
3819 
3820   if (ofClass == nullptr) {
3821     return nullptr;
3822   }
3823   Handle mirror(THREAD, JNIHandles::resolve_non_null(ofClass));
3824   // Special handling for primitive objects
3825   if (java_lang_Class::is_primitive(mirror())) {
3826     return nullptr;
3827   }
3828   Klass* k = java_lang_Class::as_Klass(mirror());
3829   if (!k->is_instance_klass()) {
3830     return nullptr;
3831   }
3832   InstanceKlass* ik = InstanceKlass::cast(k);
3833   int encl_method_class_idx = ik->enclosing_method_class_index();
3834   if (encl_method_class_idx == 0) {
3835     return nullptr;
3836   }
3837   objArrayOop dest_o = oopFactory::new_objArray(vmClasses::Object_klass(), 3, CHECK_NULL);
3838   objArrayHandle dest(THREAD, dest_o);
3839   Klass* enc_k = ik->constants()->klass_at(encl_method_class_idx, CHECK_NULL);
3840   dest->obj_at_put(0, enc_k->java_mirror());
3841   int encl_method_method_idx = ik->enclosing_method_method_index();
3842   if (encl_method_method_idx != 0) {
3843     Symbol* sym = ik->constants()->symbol_at(
3844                         extract_low_short_from_int(
3845                           ik->constants()->name_and_type_at(encl_method_method_idx)));
3846     Handle str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
3847     dest->obj_at_put(1, str());
3848     sym = ik->constants()->symbol_at(
3849               extract_high_short_from_int(
3850                 ik->constants()->name_and_type_at(encl_method_method_idx)));
3851     str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
3852     dest->obj_at_put(2, str());
3853   }
3854   return (jobjectArray) JNIHandles::make_local(THREAD, dest());
3855 }
3856 JVM_END
3857 
3858 // Returns an array of java.lang.String objects containing the input arguments to the VM.
3859 JVM_ENTRY(jobjectArray, JVM_GetVmArguments(JNIEnv *env))
3860   ResourceMark rm(THREAD);
3861 
3862   if (Arguments::num_jvm_args() == 0 && Arguments::num_jvm_flags() == 0) {
3863     return nullptr;
3864   }
3865 
3866   char** vm_flags = Arguments::jvm_flags_array();
3867   char** vm_args = Arguments::jvm_args_array();
3868   int num_flags = Arguments::num_jvm_flags();
3869   int num_args = Arguments::num_jvm_args();
3870 
3871   InstanceKlass* ik = vmClasses::String_klass();
3872   objArrayOop r = oopFactory::new_objArray(ik, num_args + num_flags, CHECK_NULL);
3873   objArrayHandle result_h(THREAD, r);
3874 
3875   int index = 0;
3876   for (int j = 0; j < num_flags; j++, index++) {
3877     Handle h = java_lang_String::create_from_platform_dependent_str(vm_flags[j], CHECK_NULL);
3878     result_h->obj_at_put(index, h());
3879   }
3880   for (int i = 0; i < num_args; i++, index++) {
3881     Handle h = java_lang_String::create_from_platform_dependent_str(vm_args[i], CHECK_NULL);
3882     result_h->obj_at_put(index, h());
3883   }
3884   return (jobjectArray) JNIHandles::make_local(THREAD, result_h());
3885 JVM_END
3886 
3887 JVM_LEAF(jint, JVM_FindSignal(const char *name))
3888   return os::get_signal_number(name);
3889 JVM_END
3890 
3891 JVM_ENTRY(void, JVM_VirtualThreadStart(JNIEnv* env, jobject vthread))
3892 #if INCLUDE_JVMTI
3893   if (!DoJVMTIVirtualThreadTransitions) {
3894     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
3895     return;
3896   }
3897   if (JvmtiVTMSTransitionDisabler::VTMS_notify_jvmti_events()) {
3898     JvmtiVTMSTransitionDisabler::VTMS_vthread_start(vthread);
3899   } else {
3900     // set VTMS transition bit value in JavaThread and java.lang.VirtualThread object
3901     JvmtiVTMSTransitionDisabler::set_is_in_VTMS_transition(thread, vthread, false);
3902   }
3903 #endif
3904 JVM_END
3905 
3906 JVM_ENTRY(void, JVM_VirtualThreadEnd(JNIEnv* env, jobject vthread))
3907 #if INCLUDE_JVMTI
3908   if (!DoJVMTIVirtualThreadTransitions) {
3909     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
3910     return;
3911   }
3912   if (JvmtiVTMSTransitionDisabler::VTMS_notify_jvmti_events()) {
3913     JvmtiVTMSTransitionDisabler::VTMS_vthread_end(vthread);
3914   } else {
3915     // set VTMS transition bit value in JavaThread and java.lang.VirtualThread object
3916     JvmtiVTMSTransitionDisabler::set_is_in_VTMS_transition(thread, vthread, true);
3917   }
3918 #endif
3919 JVM_END
3920 
3921 // If notifications are disabled then just update the VTMS transition bit and return.
3922 // Otherwise, the bit is updated in the given jvmtiVTMSTransitionDisabler function call.
3923 JVM_ENTRY(void, JVM_VirtualThreadMount(JNIEnv* env, jobject vthread, jboolean hide))
3924 #if INCLUDE_JVMTI
3925   if (!DoJVMTIVirtualThreadTransitions) {
3926     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
3927     return;
3928   }
3929   if (JvmtiVTMSTransitionDisabler::VTMS_notify_jvmti_events()) {
3930     JvmtiVTMSTransitionDisabler::VTMS_vthread_mount(vthread, hide);
3931   } else {
3932     // set VTMS transition bit value in JavaThread and java.lang.VirtualThread object
3933     JvmtiVTMSTransitionDisabler::set_is_in_VTMS_transition(thread, vthread, hide);
3934   }
3935 #endif
3936 JVM_END
3937 
3938 // If notifications are disabled then just update the VTMS transition bit and return.
3939 // Otherwise, the bit is updated in the given jvmtiVTMSTransitionDisabler function call below.
3940 JVM_ENTRY(void, JVM_VirtualThreadUnmount(JNIEnv* env, jobject vthread, jboolean hide))
3941 #if INCLUDE_JVMTI
3942   if (!DoJVMTIVirtualThreadTransitions) {
3943     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
3944     return;
3945   }
3946   if (JvmtiVTMSTransitionDisabler::VTMS_notify_jvmti_events()) {
3947     JvmtiVTMSTransitionDisabler::VTMS_vthread_unmount(vthread, hide);
3948   } else {
3949     // set VTMS transition bit value in JavaThread and java.lang.VirtualThread object
3950     JvmtiVTMSTransitionDisabler::set_is_in_VTMS_transition(thread, vthread, hide);
3951   }
3952 #endif
3953 JVM_END
3954 
3955 // Notification from VirtualThread about disabling JVMTI Suspend in a sync critical section.
3956 // Needed to avoid deadlocks with JVMTI suspend mechanism.
3957 JVM_ENTRY(void, JVM_VirtualThreadDisableSuspend(JNIEnv* env, jclass clazz, jboolean enter))
3958 #if INCLUDE_JVMTI
3959   if (!DoJVMTIVirtualThreadTransitions) {
3960     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
3961     return;
3962   }
3963   assert(thread->is_disable_suspend() != (bool)enter,
3964          "nested or unbalanced monitor enter/exit is not allowed");
3965   thread->toggle_is_disable_suspend();
3966 #endif
3967 JVM_END
3968 
3969 JVM_ENTRY(void, JVM_VirtualThreadPinnedEvent(JNIEnv* env, jclass ignored, jstring op))
3970 #if INCLUDE_JFR
3971   freeze_result result = THREAD->last_freeze_fail_result();
3972   assert(result != freeze_ok, "sanity check");
3973   EventVirtualThreadPinned event(UNTIMED);
3974   event.set_starttime(THREAD->last_freeze_fail_time());
3975   if (event.should_commit()) {
3976     ResourceMark rm(THREAD);
3977     const char *str = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(op));
3978     THREAD->post_vthread_pinned_event(&event, str, result);
3979   }
3980 #endif
3981 JVM_END
3982 
3983 JVM_ENTRY(jobject, JVM_TakeVirtualThreadListToUnblock(JNIEnv* env, jclass ignored))
3984   ParkEvent* parkEvent = ObjectMonitor::vthread_unparker_ParkEvent();
3985   assert(parkEvent != nullptr, "not initialized");
3986 
3987   OopHandle& list_head = ObjectMonitor::vthread_list_head();
3988   oop vthread_head = nullptr;
3989   while (true) {
3990     if (list_head.peek() != nullptr) {
3991       for (;;) {
3992         oop head = list_head.resolve();
3993         if (list_head.cmpxchg(head, nullptr) == head) {
3994           return JNIHandles::make_local(THREAD, head);
3995         }
3996       }
3997     }
3998     ThreadBlockInVM tbivm(THREAD);
3999     parkEvent->park();
4000   }
4001 JVM_END
4002 /*
4003  * Return the current class's class file version.  The low order 16 bits of the
4004  * returned jint contain the class's major version.  The high order 16 bits
4005  * contain the class's minor version.
4006  */
4007 JVM_ENTRY(jint, JVM_GetClassFileVersion(JNIEnv* env, jclass current))
4008   oop mirror = JNIHandles::resolve_non_null(current);
4009   if (java_lang_Class::is_primitive(mirror)) {
4010     // return latest major version and minor version of 0.
4011     return JVM_CLASSFILE_MAJOR_VERSION;
4012   }
4013   assert(!java_lang_Class::as_Klass(mirror)->is_array_klass(), "unexpected array class");
4014 
4015   Klass* c = java_lang_Class::as_Klass(mirror);
4016   assert(c->is_instance_klass(), "must be");
4017   InstanceKlass* ik = InstanceKlass::cast(c);
4018   return (ik->minor_version() << 16) | ik->major_version();
4019 JVM_END
4020 
4021 /*
4022  * Ensure that code doing a stackwalk and using javaVFrame::locals() to
4023  * get the value will see a materialized value and not a scalar-replaced
4024  * null value.
4025  */
4026 JVM_ENTRY(void, JVM_EnsureMaterializedForStackWalk_func(JNIEnv* env, jobject vthread, jobject value))
4027   JVM_EnsureMaterializedForStackWalk(env, value);
4028 JVM_END
4029 
4030 /*
4031  * Return JNI_TRUE if warnings are printed when agents are dynamically loaded.
4032  */
4033 JVM_LEAF(jboolean, JVM_PrintWarningAtDynamicAgentLoad(void))
4034   return (EnableDynamicAgentLoading && !FLAG_IS_CMDLINE(EnableDynamicAgentLoading)) ? JNI_TRUE : JNI_FALSE;
4035 JVM_END