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_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 (UseArrayFlattening && 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 (UseArrayFlattening && 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 (UseArrayFlattening && 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 JVM_ENTRY(jboolean, JVM_IsIdentityClass(JNIEnv *env, jclass cls))
1393   oop mirror = JNIHandles::resolve_non_null(cls);
1394   if (java_lang_Class::is_primitive(mirror)) {
1395     return JNI_FALSE;
1396   }
1397   Klass* k = java_lang_Class::as_Klass(mirror);
1398   if (EnableValhalla) {
1399     return k->is_array_klass() || k->is_identity_class();
1400   } else {
1401     return k->is_interface() ? JNI_FALSE : JNI_TRUE;
1402   }
1403 JVM_END
1404 
1405 class ScopedValueBindingsResolver {
1406 public:
1407   InstanceKlass* Carrier_klass;
1408   ScopedValueBindingsResolver(JavaThread* THREAD) {
1409     Klass *k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_ScopedValue_Carrier(), true, THREAD);
1410     Carrier_klass = InstanceKlass::cast(k);
1411   }
1412 };
1413 
1414 JVM_ENTRY(jobject, JVM_FindScopedValueBindings(JNIEnv *env, jclass cls))
1415   ResourceMark rm(THREAD);
1416   GrowableArray<Handle>* local_array = new GrowableArray<Handle>(12);
1417   JvmtiVMObjectAllocEventCollector oam;
1418 
1419   static ScopedValueBindingsResolver resolver(THREAD);
1420 
1421   // Iterate through Java frames
1422   vframeStream vfst(thread);
1423   for(; !vfst.at_end(); vfst.next()) {
1424     int loc = -1;
1425     // get method of frame
1426     Method* method = vfst.method();
1427 
1428     Symbol *name = method->name();
1429 
1430     InstanceKlass* holder = method->method_holder();
1431     if (name == vmSymbols::runWith_method_name()) {
1432       if (holder == vmClasses::Thread_klass()
1433           || holder == resolver.Carrier_klass) {
1434         loc = 1;
1435       }
1436     }
1437 
1438     if (loc != -1) {
1439       javaVFrame *frame = vfst.asJavaVFrame();
1440       StackValueCollection* locals = frame->locals();
1441       StackValue* head_sv = locals->at(loc); // java/lang/ScopedValue$Snapshot
1442       Handle result = head_sv->get_obj();
1443       assert(!head_sv->obj_is_scalar_replaced(), "found scalar-replaced object");
1444       if (result() != nullptr) {
1445         return JNIHandles::make_local(THREAD, result());
1446       }
1447     }
1448   }
1449 
1450   return nullptr;
1451 JVM_END
1452 
1453 JVM_ENTRY(jobjectArray, JVM_GetDeclaredClasses(JNIEnv *env, jclass ofClass))
1454   JvmtiVMObjectAllocEventCollector oam;
1455   // ofClass is a reference to a java_lang_Class object. The mirror object
1456   // of an InstanceKlass
1457   oop ofMirror = JNIHandles::resolve_non_null(ofClass);
1458   if (java_lang_Class::is_primitive(ofMirror) ||
1459       ! java_lang_Class::as_Klass(ofMirror)->is_instance_klass()) {
1460     oop result = oopFactory::new_objArray(vmClasses::Class_klass(), 0, CHECK_NULL);
1461     return (jobjectArray)JNIHandles::make_local(THREAD, result);
1462   }
1463 
1464   InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(ofMirror));
1465   InnerClassesIterator iter(k);
1466 
1467   if (iter.length() == 0) {
1468     // Neither an inner nor outer class
1469     oop result = oopFactory::new_objArray(vmClasses::Class_klass(), 0, CHECK_NULL);
1470     return (jobjectArray)JNIHandles::make_local(THREAD, result);
1471   }
1472 
1473   // find inner class info
1474   constantPoolHandle cp(thread, k->constants());
1475   int length = iter.length();
1476 
1477   // Allocate temp. result array
1478   objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(), length/4, CHECK_NULL);
1479   objArrayHandle result (THREAD, r);
1480   int members = 0;
1481 
1482   for (; !iter.done(); iter.next()) {
1483     int ioff = iter.inner_class_info_index();
1484     int ooff = iter.outer_class_info_index();
1485 
1486     if (ioff != 0 && ooff != 0) {
1487       // Check to see if the name matches the class we're looking for
1488       // before attempting to find the class.
1489       if (cp->klass_name_at_matches(k, ooff)) {
1490         Klass* outer_klass = cp->klass_at(ooff, CHECK_NULL);
1491         if (outer_klass == k) {
1492            Klass* ik = cp->klass_at(ioff, CHECK_NULL);
1493            InstanceKlass* inner_klass = InstanceKlass::cast(ik);
1494 
1495            // Throws an exception if outer klass has not declared k as
1496            // an inner klass
1497            Reflection::check_for_inner_class(k, inner_klass, true, CHECK_NULL);
1498 
1499            result->obj_at_put(members, inner_klass->java_mirror());
1500            members++;
1501         }
1502       }
1503     }
1504   }
1505 
1506   if (members != length) {
1507     // Return array of right length
1508     objArrayOop res = oopFactory::new_objArray(vmClasses::Class_klass(), members, CHECK_NULL);
1509     for(int i = 0; i < members; i++) {
1510       res->obj_at_put(i, result->obj_at(i));
1511     }
1512     return (jobjectArray)JNIHandles::make_local(THREAD, res);
1513   }
1514 
1515   return (jobjectArray)JNIHandles::make_local(THREAD, result());
1516 JVM_END
1517 
1518 
1519 JVM_ENTRY(jclass, JVM_GetDeclaringClass(JNIEnv *env, jclass ofClass))
1520 {
1521   // ofClass is a reference to a java_lang_Class object.
1522   oop ofMirror = JNIHandles::resolve_non_null(ofClass);
1523   if (java_lang_Class::is_primitive(ofMirror)) {
1524     return nullptr;
1525   }
1526   Klass* klass = java_lang_Class::as_Klass(ofMirror);
1527   if (!klass->is_instance_klass()) {
1528     return nullptr;
1529   }
1530 
1531   bool inner_is_member = false;
1532   Klass* outer_klass
1533     = InstanceKlass::cast(klass)->compute_enclosing_class(&inner_is_member, CHECK_NULL);
1534   if (outer_klass == nullptr)  return nullptr;  // already a top-level class
1535   if (!inner_is_member)  return nullptr;     // a hidden class (inside a method)
1536   return (jclass) JNIHandles::make_local(THREAD, outer_klass->java_mirror());
1537 }
1538 JVM_END
1539 
1540 JVM_ENTRY(jstring, JVM_GetSimpleBinaryName(JNIEnv *env, jclass cls))
1541 {
1542   oop mirror = JNIHandles::resolve_non_null(cls);
1543   if (java_lang_Class::is_primitive(mirror)) {
1544     return nullptr;
1545   }
1546   Klass* klass = java_lang_Class::as_Klass(mirror);
1547   if (!klass->is_instance_klass()) {
1548     return nullptr;
1549   }
1550   InstanceKlass* k = InstanceKlass::cast(klass);
1551   int ooff = 0, noff = 0;
1552   if (k->find_inner_classes_attr(&ooff, &noff, THREAD)) {
1553     if (noff != 0) {
1554       constantPoolHandle i_cp(thread, k->constants());
1555       Symbol* name = i_cp->symbol_at(noff);
1556       Handle str = java_lang_String::create_from_symbol(name, CHECK_NULL);
1557       return (jstring) JNIHandles::make_local(THREAD, str());
1558     }
1559   }
1560   return nullptr;
1561 }
1562 JVM_END
1563 
1564 JVM_ENTRY(jstring, JVM_GetClassSignature(JNIEnv *env, jclass cls))
1565   assert (cls != nullptr, "illegal class");
1566   JvmtiVMObjectAllocEventCollector oam;
1567   ResourceMark rm(THREAD);
1568   oop mirror = JNIHandles::resolve_non_null(cls);
1569   // Return null for arrays and primitives
1570   if (!java_lang_Class::is_primitive(mirror)) {
1571     Klass* k = java_lang_Class::as_Klass(mirror);
1572     if (k->is_instance_klass()) {
1573       Symbol* sym = InstanceKlass::cast(k)->generic_signature();
1574       if (sym == nullptr) return nullptr;
1575       Handle str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
1576       return (jstring) JNIHandles::make_local(THREAD, str());
1577     }
1578   }
1579   return nullptr;
1580 JVM_END
1581 
1582 
1583 JVM_ENTRY(jbyteArray, JVM_GetClassAnnotations(JNIEnv *env, jclass cls))
1584   assert (cls != nullptr, "illegal class");
1585   oop mirror = JNIHandles::resolve_non_null(cls);
1586   // Return null for arrays and primitives
1587   if (!java_lang_Class::is_primitive(mirror)) {
1588     Klass* k = java_lang_Class::as_Klass(mirror);
1589     if (k->is_instance_klass()) {
1590       typeArrayOop a = Annotations::make_java_array(InstanceKlass::cast(k)->class_annotations(), CHECK_NULL);
1591       return (jbyteArray) JNIHandles::make_local(THREAD, a);
1592     }
1593   }
1594   return nullptr;
1595 JVM_END
1596 
1597 
1598 static bool jvm_get_field_common(jobject field, fieldDescriptor& fd) {
1599   // some of this code was adapted from from jni_FromReflectedField
1600 
1601   oop reflected = JNIHandles::resolve_non_null(field);
1602   oop mirror    = java_lang_reflect_Field::clazz(reflected);
1603   Klass* k    = java_lang_Class::as_Klass(mirror);
1604   int slot      = java_lang_reflect_Field::slot(reflected);
1605   int modifiers = java_lang_reflect_Field::modifiers(reflected);
1606 
1607   InstanceKlass* ik = InstanceKlass::cast(k);
1608   int offset = ik->field_offset(slot);
1609 
1610   if (modifiers & JVM_ACC_STATIC) {
1611     // for static fields we only look in the current class
1612     if (!ik->find_local_field_from_offset(offset, true, &fd)) {
1613       assert(false, "cannot find static field");
1614       return false;
1615     }
1616   } else {
1617     // for instance fields we start with the current class and work
1618     // our way up through the superclass chain
1619     if (!ik->find_field_from_offset(offset, false, &fd)) {
1620       assert(false, "cannot find instance field");
1621       return false;
1622     }
1623   }
1624   return true;
1625 }
1626 
1627 static Method* jvm_get_method_common(jobject method) {
1628   // some of this code was adapted from from jni_FromReflectedMethod
1629 
1630   oop reflected = JNIHandles::resolve_non_null(method);
1631   oop mirror    = nullptr;
1632   int slot      = 0;
1633 
1634   if (reflected->klass() == vmClasses::reflect_Constructor_klass()) {
1635     mirror = java_lang_reflect_Constructor::clazz(reflected);
1636     slot   = java_lang_reflect_Constructor::slot(reflected);
1637   } else {
1638     assert(reflected->klass() == vmClasses::reflect_Method_klass(),
1639            "wrong type");
1640     mirror = java_lang_reflect_Method::clazz(reflected);
1641     slot   = java_lang_reflect_Method::slot(reflected);
1642   }
1643   Klass* k = java_lang_Class::as_Klass(mirror);
1644 
1645   Method* m = InstanceKlass::cast(k)->method_with_idnum(slot);
1646   assert(m != nullptr, "cannot find method");
1647   return m;  // caller has to deal with null in product mode
1648 }
1649 
1650 /* Type use annotations support (JDK 1.8) */
1651 
1652 JVM_ENTRY(jbyteArray, JVM_GetClassTypeAnnotations(JNIEnv *env, jclass cls))
1653   assert (cls != nullptr, "illegal class");
1654   ResourceMark rm(THREAD);
1655   // Return null for arrays and primitives
1656   if (!java_lang_Class::is_primitive(JNIHandles::resolve(cls))) {
1657     Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve(cls));
1658     if (k->is_instance_klass()) {
1659       AnnotationArray* type_annotations = InstanceKlass::cast(k)->class_type_annotations();
1660       if (type_annotations != nullptr) {
1661         typeArrayOop a = Annotations::make_java_array(type_annotations, CHECK_NULL);
1662         return (jbyteArray) JNIHandles::make_local(THREAD, a);
1663       }
1664     }
1665   }
1666   return nullptr;
1667 JVM_END
1668 
1669 JVM_ENTRY(jbyteArray, JVM_GetMethodTypeAnnotations(JNIEnv *env, jobject method))
1670   assert (method != nullptr, "illegal method");
1671   // method is a handle to a java.lang.reflect.Method object
1672   Method* m = jvm_get_method_common(method);
1673   if (m == nullptr) {
1674     return nullptr;
1675   }
1676 
1677   AnnotationArray* type_annotations = m->type_annotations();
1678   if (type_annotations != nullptr) {
1679     typeArrayOop a = Annotations::make_java_array(type_annotations, CHECK_NULL);
1680     return (jbyteArray) JNIHandles::make_local(THREAD, a);
1681   }
1682 
1683   return nullptr;
1684 JVM_END
1685 
1686 JVM_ENTRY(jbyteArray, JVM_GetFieldTypeAnnotations(JNIEnv *env, jobject field))
1687   assert (field != nullptr, "illegal field");
1688   fieldDescriptor fd;
1689   bool gotFd = jvm_get_field_common(field, fd);
1690   if (!gotFd) {
1691     return nullptr;
1692   }
1693 
1694   return (jbyteArray) JNIHandles::make_local(THREAD, Annotations::make_java_array(fd.type_annotations(), THREAD));
1695 JVM_END
1696 
1697 static void bounds_check(const constantPoolHandle& cp, jint index, TRAPS) {
1698   if (!cp->is_within_bounds(index)) {
1699     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "Constant pool index out of bounds");
1700   }
1701 }
1702 
1703 JVM_ENTRY(jobjectArray, JVM_GetMethodParameters(JNIEnv *env, jobject method))
1704 {
1705   // method is a handle to a java.lang.reflect.Method object
1706   Method* method_ptr = jvm_get_method_common(method);
1707   methodHandle mh (THREAD, method_ptr);
1708   Handle reflected_method (THREAD, JNIHandles::resolve_non_null(method));
1709   const int num_params = mh->method_parameters_length();
1710 
1711   if (num_params < 0) {
1712     // A -1 return value from method_parameters_length means there is no
1713     // parameter data.  Return null to indicate this to the reflection
1714     // API.
1715     assert(num_params == -1, "num_params should be -1 if it is less than zero");
1716     return (jobjectArray)nullptr;
1717   } else {
1718     // Otherwise, we return something up to reflection, even if it is
1719     // a zero-length array.  Why?  Because in some cases this can
1720     // trigger a MalformedParametersException.
1721 
1722     // make sure all the symbols are properly formatted
1723     for (int i = 0; i < num_params; i++) {
1724       MethodParametersElement* params = mh->method_parameters_start();
1725       int index = params[i].name_cp_index;
1726       constantPoolHandle cp(THREAD, mh->constants());
1727       bounds_check(cp, index, CHECK_NULL);
1728 
1729       if (0 != index && !mh->constants()->tag_at(index).is_utf8()) {
1730         THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(),
1731                        "Wrong type at constant pool index");
1732       }
1733 
1734     }
1735 
1736     objArrayOop result_oop = oopFactory::new_objArray(vmClasses::reflect_Parameter_klass(), num_params, CHECK_NULL);
1737     objArrayHandle result (THREAD, result_oop);
1738 
1739     for (int i = 0; i < num_params; i++) {
1740       MethodParametersElement* params = mh->method_parameters_start();
1741       // For a 0 index, give a null symbol
1742       Symbol* sym = 0 != params[i].name_cp_index ?
1743         mh->constants()->symbol_at(params[i].name_cp_index) : nullptr;
1744       int flags = params[i].flags;
1745       oop param = Reflection::new_parameter(reflected_method, i, sym,
1746                                             flags, CHECK_NULL);
1747       result->obj_at_put(i, param);
1748     }
1749     return (jobjectArray)JNIHandles::make_local(THREAD, result());
1750   }
1751 }
1752 JVM_END
1753 
1754 // New (JDK 1.4) reflection implementation /////////////////////////////////////
1755 
1756 JVM_ENTRY(jobjectArray, JVM_GetClassDeclaredFields(JNIEnv *env, jclass ofClass, jboolean publicOnly))
1757 {
1758   JvmtiVMObjectAllocEventCollector oam;
1759 
1760   oop ofMirror = JNIHandles::resolve_non_null(ofClass);
1761   // Exclude primitive types and array types
1762   if (java_lang_Class::is_primitive(ofMirror) ||
1763       java_lang_Class::as_Klass(ofMirror)->is_array_klass()) {
1764     // Return empty array
1765     oop res = oopFactory::new_objArray(vmClasses::reflect_Field_klass(), 0, CHECK_NULL);
1766     return (jobjectArray) JNIHandles::make_local(THREAD, res);
1767   }
1768 
1769   InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(ofMirror));
1770   constantPoolHandle cp(THREAD, k->constants());
1771 
1772   // Ensure class is linked
1773   k->link_class(CHECK_NULL);
1774 
1775   // Allocate result
1776   int num_fields;
1777 
1778   if (publicOnly) {
1779     num_fields = 0;
1780     for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
1781       if (fs.access_flags().is_public()) ++num_fields;
1782     }
1783   } else {
1784     num_fields = k->java_fields_count();
1785   }
1786 
1787   objArrayOop r = oopFactory::new_objArray(vmClasses::reflect_Field_klass(), num_fields, CHECK_NULL);
1788   objArrayHandle result (THREAD, r);
1789 
1790   int out_idx = 0;
1791   fieldDescriptor fd;
1792   for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
1793     if (!publicOnly || fs.access_flags().is_public()) {
1794       fd.reinitialize(k, fs.index());
1795       oop field = Reflection::new_field(&fd, CHECK_NULL);
1796       result->obj_at_put(out_idx, field);
1797       ++out_idx;
1798     }
1799   }
1800   assert(out_idx == num_fields, "just checking");
1801   return (jobjectArray) JNIHandles::make_local(THREAD, result());
1802 }
1803 JVM_END
1804 
1805 // A class is a record if and only if it is final and a direct subclass of
1806 // java.lang.Record and has a Record attribute; otherwise, it is not a record.
1807 JVM_ENTRY(jboolean, JVM_IsRecord(JNIEnv *env, jclass cls))
1808 {
1809   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
1810   if (k != nullptr && k->is_instance_klass()) {
1811     InstanceKlass* ik = InstanceKlass::cast(k);
1812     return ik->is_record();
1813   } else {
1814     return false;
1815   }
1816 }
1817 JVM_END
1818 
1819 // Returns an array containing the components of the Record attribute,
1820 // or null if the attribute is not present.
1821 //
1822 // Note that this function returns the components of the Record attribute
1823 // even if the class is not a record.
1824 JVM_ENTRY(jobjectArray, JVM_GetRecordComponents(JNIEnv* env, jclass ofClass))
1825 {
1826   Klass* c = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(ofClass));
1827   assert(c->is_instance_klass(), "must be");
1828   InstanceKlass* ik = InstanceKlass::cast(c);
1829 
1830   Array<RecordComponent*>* components = ik->record_components();
1831   if (components != nullptr) {
1832     JvmtiVMObjectAllocEventCollector oam;
1833     constantPoolHandle cp(THREAD, ik->constants());
1834     int length = components->length();
1835     assert(length >= 0, "unexpected record_components length");
1836     objArrayOop record_components =
1837       oopFactory::new_objArray(vmClasses::RecordComponent_klass(), length, CHECK_NULL);
1838     objArrayHandle components_h (THREAD, record_components);
1839 
1840     for (int x = 0; x < length; x++) {
1841       RecordComponent* component = components->at(x);
1842       assert(component != nullptr, "unexpected null record component");
1843       oop component_oop = java_lang_reflect_RecordComponent::create(ik, component, CHECK_NULL);
1844       components_h->obj_at_put(x, component_oop);
1845     }
1846     return (jobjectArray)JNIHandles::make_local(THREAD, components_h());
1847   }
1848 
1849   return nullptr;
1850 }
1851 JVM_END
1852 
1853 static jobjectArray get_class_declared_methods_helper(
1854                                   JNIEnv *env,
1855                                   jclass ofClass, jboolean publicOnly,
1856                                   bool want_constructor,
1857                                   Klass* klass, TRAPS) {
1858 
1859   JvmtiVMObjectAllocEventCollector oam;
1860 
1861   oop ofMirror = JNIHandles::resolve_non_null(ofClass);
1862   // Exclude primitive types and array types
1863   if (java_lang_Class::is_primitive(ofMirror)
1864       || java_lang_Class::as_Klass(ofMirror)->is_array_klass()) {
1865     // Return empty array
1866     oop res = oopFactory::new_objArray(klass, 0, CHECK_NULL);
1867     return (jobjectArray) JNIHandles::make_local(THREAD, res);
1868   }
1869 
1870   InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(ofMirror));
1871 
1872   // Ensure class is linked
1873   k->link_class(CHECK_NULL);
1874 
1875   Array<Method*>* methods = k->methods();
1876   int methods_length = methods->length();
1877 
1878   // Save original method_idnum in case of redefinition, which can change
1879   // the idnum of obsolete methods.  The new method will have the same idnum
1880   // but if we refresh the methods array, the counts will be wrong.
1881   ResourceMark rm(THREAD);
1882   GrowableArray<int>* idnums = new GrowableArray<int>(methods_length);
1883   int num_methods = 0;
1884 
1885   // Select methods matching the criteria.
1886   for (int i = 0; i < methods_length; i++) {
1887     Method* method = methods->at(i);
1888     if (want_constructor && !method->is_object_constructor()) {
1889       continue;
1890     }
1891     if (!want_constructor &&
1892         (method->is_object_constructor() || method->is_class_initializer() ||
1893          method->is_overpass())) {
1894       continue;
1895     }
1896     if (publicOnly && !method->is_public()) {
1897       continue;
1898     }
1899     idnums->push(method->method_idnum());
1900     ++num_methods;
1901   }
1902 
1903   // Allocate result
1904   objArrayOop r = oopFactory::new_objArray(klass, num_methods, CHECK_NULL);
1905   objArrayHandle result (THREAD, r);
1906 
1907   // Now just put the methods that we selected above, but go by their idnum
1908   // in case of redefinition.  The methods can be redefined at any safepoint,
1909   // so above when allocating the oop array and below when creating reflect
1910   // objects.
1911   for (int i = 0; i < num_methods; i++) {
1912     methodHandle method(THREAD, k->method_with_idnum(idnums->at(i)));
1913     if (method.is_null()) {
1914       // Method may have been deleted and seems this API can handle null
1915       // Otherwise should probably put a method that throws NSME
1916       result->obj_at_put(i, nullptr);
1917     } else {
1918       oop m;
1919       if (want_constructor) {
1920         assert(method->is_object_constructor(), "must be");
1921         m = Reflection::new_constructor(method, CHECK_NULL);
1922       } else {
1923         m = Reflection::new_method(method, false, CHECK_NULL);
1924       }
1925       result->obj_at_put(i, m);
1926     }
1927   }
1928 
1929   return (jobjectArray) JNIHandles::make_local(THREAD, result());
1930 }
1931 
1932 JVM_ENTRY(jobjectArray, JVM_GetClassDeclaredMethods(JNIEnv *env, jclass ofClass, jboolean publicOnly))
1933 {
1934   return get_class_declared_methods_helper(env, ofClass, publicOnly,
1935                                            /*want_constructor*/ false,
1936                                            vmClasses::reflect_Method_klass(), THREAD);
1937 }
1938 JVM_END
1939 
1940 JVM_ENTRY(jobjectArray, JVM_GetClassDeclaredConstructors(JNIEnv *env, jclass ofClass, jboolean publicOnly))
1941 {
1942   return get_class_declared_methods_helper(env, ofClass, publicOnly,
1943                                            /*want_constructor*/ true,
1944                                            vmClasses::reflect_Constructor_klass(), THREAD);
1945 }
1946 JVM_END
1947 
1948 JVM_ENTRY(jint, JVM_GetClassAccessFlags(JNIEnv *env, jclass cls))
1949 {
1950   oop mirror = JNIHandles::resolve_non_null(cls);
1951   if (java_lang_Class::is_primitive(mirror)) {
1952     // Primitive type
1953     return JVM_ACC_ABSTRACT | JVM_ACC_FINAL | JVM_ACC_PUBLIC;
1954   }
1955 
1956   Klass* k = java_lang_Class::as_Klass(mirror);
1957   return k->access_flags().as_class_flags();
1958 }
1959 JVM_END
1960 
1961 JVM_ENTRY(jboolean, JVM_AreNestMates(JNIEnv *env, jclass current, jclass member))
1962 {
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   Klass* m = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(member));
1967   assert(m->is_instance_klass(), "must be");
1968   InstanceKlass* mk = InstanceKlass::cast(m);
1969   return ck->has_nestmate_access_to(mk, THREAD);
1970 }
1971 JVM_END
1972 
1973 JVM_ENTRY(jclass, JVM_GetNestHost(JNIEnv* env, jclass current))
1974 {
1975   // current is not a primitive or array class
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   return (jclass) (host == nullptr ? nullptr :
1981                    JNIHandles::make_local(THREAD, host->java_mirror()));
1982 }
1983 JVM_END
1984 
1985 JVM_ENTRY(jobjectArray, JVM_GetNestMembers(JNIEnv* env, jclass current))
1986 {
1987   // current is not a primitive or array class
1988   ResourceMark rm(THREAD);
1989   Klass* c = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(current));
1990   assert(c->is_instance_klass(), "must be");
1991   InstanceKlass* ck = InstanceKlass::cast(c);
1992   InstanceKlass* host = ck->nest_host(THREAD);
1993 
1994   log_trace(class, nestmates)("Calling GetNestMembers for type %s with nest-host %s",
1995                               ck->external_name(), host->external_name());
1996   {
1997     JvmtiVMObjectAllocEventCollector oam;
1998     Array<u2>* members = host->nest_members();
1999     int length = members == nullptr ? 0 : members->length();
2000 
2001     log_trace(class, nestmates)(" - host has %d listed nest members", length);
2002 
2003     // nest host is first in the array so make it one bigger
2004     objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(),
2005                                              length + 1, CHECK_NULL);
2006     objArrayHandle result(THREAD, r);
2007     result->obj_at_put(0, host->java_mirror());
2008     if (length != 0) {
2009       int count = 0;
2010       for (int i = 0; i < length; i++) {
2011         int cp_index = members->at(i);
2012         Klass* k = host->constants()->klass_at(cp_index, THREAD);
2013         if (HAS_PENDING_EXCEPTION) {
2014           if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
2015             return nullptr; // propagate VMEs
2016           }
2017           if (log_is_enabled(Trace, class, nestmates)) {
2018             stringStream ss;
2019             char* target_member_class = host->constants()->klass_name_at(cp_index)->as_C_string();
2020             ss.print(" - resolution of nest member %s failed: ", target_member_class);
2021             java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
2022             log_trace(class, nestmates)("%s", ss.as_string());
2023           }
2024           CLEAR_PENDING_EXCEPTION;
2025           continue;
2026         }
2027         if (k->is_instance_klass()) {
2028           InstanceKlass* ik = InstanceKlass::cast(k);
2029           InstanceKlass* nest_host_k = ik->nest_host(CHECK_NULL);
2030           if (nest_host_k == host) {
2031             result->obj_at_put(count+1, k->java_mirror());
2032             count++;
2033             log_trace(class, nestmates)(" - [%d] = %s", count, ik->external_name());
2034           } else {
2035             log_trace(class, nestmates)(" - skipping member %s with different host %s",
2036                                         ik->external_name(), nest_host_k->external_name());
2037           }
2038         } else {
2039           log_trace(class, nestmates)(" - skipping member %s that is not an instance class",
2040                                       k->external_name());
2041         }
2042       }
2043       if (count < length) {
2044         // we had invalid entries so we need to compact the array
2045         log_trace(class, nestmates)(" - compacting array from length %d to %d",
2046                                     length + 1, count + 1);
2047 
2048         objArrayOop r2 = oopFactory::new_objArray(vmClasses::Class_klass(),
2049                                                   count + 1, CHECK_NULL);
2050         objArrayHandle result2(THREAD, r2);
2051         for (int i = 0; i < count + 1; i++) {
2052           result2->obj_at_put(i, result->obj_at(i));
2053         }
2054         return (jobjectArray)JNIHandles::make_local(THREAD, result2());
2055       }
2056     }
2057     else {
2058       assert(host == ck || ck->is_hidden(), "must be singleton nest or dynamic nestmate");
2059     }
2060     return (jobjectArray)JNIHandles::make_local(THREAD, result());
2061   }
2062 }
2063 JVM_END
2064 
2065 JVM_ENTRY(jobjectArray, JVM_GetPermittedSubclasses(JNIEnv* env, jclass current))
2066 {
2067   oop mirror = JNIHandles::resolve_non_null(current);
2068   assert(!java_lang_Class::is_primitive(mirror), "should not be");
2069   Klass* c = java_lang_Class::as_Klass(mirror);
2070   assert(c->is_instance_klass(), "must be");
2071   InstanceKlass* ik = InstanceKlass::cast(c);
2072   ResourceMark rm(THREAD);
2073   log_trace(class, sealed)("Calling GetPermittedSubclasses for %s type %s",
2074                            ik->is_sealed() ? "sealed" : "non-sealed", ik->external_name());
2075   if (ik->is_sealed()) {
2076     JvmtiVMObjectAllocEventCollector oam;
2077     Array<u2>* subclasses = ik->permitted_subclasses();
2078     int length = subclasses->length();
2079 
2080     log_trace(class, sealed)(" - sealed class has %d permitted subclasses", length);
2081 
2082     objArrayOop r = oopFactory::new_objArray(vmClasses::Class_klass(),
2083                                              length, CHECK_NULL);
2084     objArrayHandle result(THREAD, r);
2085     int count = 0;
2086     for (int i = 0; i < length; i++) {
2087       int cp_index = subclasses->at(i);
2088       Klass* k = ik->constants()->klass_at(cp_index, THREAD);
2089       if (HAS_PENDING_EXCEPTION) {
2090         if (PENDING_EXCEPTION->is_a(vmClasses::VirtualMachineError_klass())) {
2091           return nullptr; // propagate VMEs
2092         }
2093         if (log_is_enabled(Trace, class, sealed)) {
2094           stringStream ss;
2095           char* permitted_subclass = ik->constants()->klass_name_at(cp_index)->as_C_string();
2096           ss.print(" - resolution of permitted subclass %s failed: ", permitted_subclass);
2097           java_lang_Throwable::print(PENDING_EXCEPTION, &ss);
2098           log_trace(class, sealed)("%s", ss.as_string());
2099         }
2100 
2101         CLEAR_PENDING_EXCEPTION;
2102         continue;
2103       }
2104       if (k->is_instance_klass()) {
2105         result->obj_at_put(count++, k->java_mirror());
2106         log_trace(class, sealed)(" - [%d] = %s", count, k->external_name());
2107       }
2108     }
2109     if (count < length) {
2110       // we had invalid entries so we need to compact the array
2111       objArrayOop r2 = oopFactory::new_objArray(vmClasses::Class_klass(),
2112                                                 count, CHECK_NULL);
2113       objArrayHandle result2(THREAD, r2);
2114       for (int i = 0; i < count; i++) {
2115         result2->obj_at_put(i, result->obj_at(i));
2116       }
2117       return (jobjectArray)JNIHandles::make_local(THREAD, result2());
2118     }
2119     return (jobjectArray)JNIHandles::make_local(THREAD, result());
2120   } else {
2121     return nullptr;
2122   }
2123 }
2124 JVM_END
2125 
2126 // Constant pool access //////////////////////////////////////////////////////////
2127 
2128 JVM_ENTRY(jobject, JVM_GetClassConstantPool(JNIEnv *env, jclass cls))
2129 {
2130   JvmtiVMObjectAllocEventCollector oam;
2131   oop mirror = JNIHandles::resolve_non_null(cls);
2132   // Return null for primitives and arrays
2133   if (!java_lang_Class::is_primitive(mirror)) {
2134     Klass* k = java_lang_Class::as_Klass(mirror);
2135     if (k->is_instance_klass()) {
2136       InstanceKlass* k_h = InstanceKlass::cast(k);
2137       Handle jcp = reflect_ConstantPool::create(CHECK_NULL);
2138       reflect_ConstantPool::set_cp(jcp(), k_h->constants());
2139       return JNIHandles::make_local(THREAD, jcp());
2140     }
2141   }
2142   return nullptr;
2143 }
2144 JVM_END
2145 
2146 
2147 JVM_ENTRY(jint, JVM_ConstantPoolGetSize(JNIEnv *env, jobject obj, jobject unused))
2148 {
2149   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2150   return cp->length();
2151 }
2152 JVM_END
2153 
2154 
2155 JVM_ENTRY(jclass, JVM_ConstantPoolGetClassAt(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 = cp->klass_at(index, CHECK_NULL);
2164   return (jclass) JNIHandles::make_local(THREAD, k->java_mirror());
2165 }
2166 JVM_END
2167 
2168 JVM_ENTRY(jclass, JVM_ConstantPoolGetClassAtIfLoaded(JNIEnv *env, jobject obj, jobject unused, jint index))
2169 {
2170   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2171   bounds_check(cp, index, CHECK_NULL);
2172   constantTag tag = cp->tag_at(index);
2173   if (!tag.is_klass() && !tag.is_unresolved_klass()) {
2174     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2175   }
2176   Klass* k = ConstantPool::klass_at_if_loaded(cp, index);
2177   if (k == nullptr) return nullptr;
2178   return (jclass) JNIHandles::make_local(THREAD, k->java_mirror());
2179 }
2180 JVM_END
2181 
2182 static jobject get_method_at_helper(const constantPoolHandle& cp, jint index, bool force_resolution, TRAPS) {
2183   constantTag tag = cp->tag_at(index);
2184   if (!tag.is_method() && !tag.is_interface_method()) {
2185     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2186   }
2187   int klass_ref  = cp->uncached_klass_ref_index_at(index);
2188   Klass* k_o;
2189   if (force_resolution) {
2190     k_o = cp->klass_at(klass_ref, CHECK_NULL);
2191   } else {
2192     k_o = ConstantPool::klass_at_if_loaded(cp, klass_ref);
2193     if (k_o == nullptr) return nullptr;
2194   }
2195   InstanceKlass* k = InstanceKlass::cast(k_o);
2196   Symbol* name = cp->uncached_name_ref_at(index);
2197   Symbol* sig  = cp->uncached_signature_ref_at(index);
2198   methodHandle m (THREAD, k->find_method(name, sig));
2199   if (m.is_null()) {
2200     THROW_MSG_NULL(vmSymbols::java_lang_RuntimeException(), "Unable to look up method in target class");
2201   }
2202   oop method;
2203   if (m->is_object_constructor()) {
2204     method = Reflection::new_constructor(m, CHECK_NULL);
2205   } else {
2206     method = Reflection::new_method(m, true, CHECK_NULL);
2207   }
2208   return JNIHandles::make_local(THREAD, method);
2209 }
2210 
2211 JVM_ENTRY(jobject, JVM_ConstantPoolGetMethodAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2212 {
2213   JvmtiVMObjectAllocEventCollector oam;
2214   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2215   bounds_check(cp, index, CHECK_NULL);
2216   jobject res = get_method_at_helper(cp, index, true, CHECK_NULL);
2217   return res;
2218 }
2219 JVM_END
2220 
2221 JVM_ENTRY(jobject, JVM_ConstantPoolGetMethodAtIfLoaded(JNIEnv *env, jobject obj, jobject unused, jint index))
2222 {
2223   JvmtiVMObjectAllocEventCollector oam;
2224   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2225   bounds_check(cp, index, CHECK_NULL);
2226   jobject res = get_method_at_helper(cp, index, false, CHECK_NULL);
2227   return res;
2228 }
2229 JVM_END
2230 
2231 static jobject get_field_at_helper(constantPoolHandle cp, jint index, bool force_resolution, TRAPS) {
2232   constantTag tag = cp->tag_at(index);
2233   if (!tag.is_field()) {
2234     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2235   }
2236   int klass_ref  = cp->uncached_klass_ref_index_at(index);
2237   Klass* k_o;
2238   if (force_resolution) {
2239     k_o = cp->klass_at(klass_ref, CHECK_NULL);
2240   } else {
2241     k_o = ConstantPool::klass_at_if_loaded(cp, klass_ref);
2242     if (k_o == nullptr) return nullptr;
2243   }
2244   InstanceKlass* k = InstanceKlass::cast(k_o);
2245   Symbol* name = cp->uncached_name_ref_at(index);
2246   Symbol* sig  = cp->uncached_signature_ref_at(index);
2247   fieldDescriptor fd;
2248   Klass* target_klass = k->find_field(name, sig, &fd);
2249   if (target_klass == nullptr) {
2250     THROW_MSG_NULL(vmSymbols::java_lang_RuntimeException(), "Unable to look up field in target class");
2251   }
2252   oop field = Reflection::new_field(&fd, CHECK_NULL);
2253   return JNIHandles::make_local(THREAD, field);
2254 }
2255 
2256 JVM_ENTRY(jobject, JVM_ConstantPoolGetFieldAt(JNIEnv *env, jobject obj, jobject unusedl, jint index))
2257 {
2258   JvmtiVMObjectAllocEventCollector oam;
2259   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2260   bounds_check(cp, index, CHECK_NULL);
2261   jobject res = get_field_at_helper(cp, index, true, CHECK_NULL);
2262   return res;
2263 }
2264 JVM_END
2265 
2266 JVM_ENTRY(jobject, JVM_ConstantPoolGetFieldAtIfLoaded(JNIEnv *env, jobject obj, jobject unused, jint index))
2267 {
2268   JvmtiVMObjectAllocEventCollector oam;
2269   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2270   bounds_check(cp, index, CHECK_NULL);
2271   jobject res = get_field_at_helper(cp, index, false, CHECK_NULL);
2272   return res;
2273 }
2274 JVM_END
2275 
2276 JVM_ENTRY(jobjectArray, JVM_ConstantPoolGetMemberRefInfoAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2277 {
2278   JvmtiVMObjectAllocEventCollector oam;
2279   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2280   bounds_check(cp, index, CHECK_NULL);
2281   constantTag tag = cp->tag_at(index);
2282   if (!tag.is_field_or_method()) {
2283     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2284   }
2285   int klass_ref = cp->uncached_klass_ref_index_at(index);
2286   Symbol*  klass_name  = cp->klass_name_at(klass_ref);
2287   Symbol*  member_name = cp->uncached_name_ref_at(index);
2288   Symbol*  member_sig  = cp->uncached_signature_ref_at(index);
2289   objArrayOop  dest_o = oopFactory::new_objArray(vmClasses::String_klass(), 3, CHECK_NULL);
2290   objArrayHandle dest(THREAD, dest_o);
2291   Handle str = java_lang_String::create_from_symbol(klass_name, CHECK_NULL);
2292   dest->obj_at_put(0, str());
2293   str = java_lang_String::create_from_symbol(member_name, CHECK_NULL);
2294   dest->obj_at_put(1, str());
2295   str = java_lang_String::create_from_symbol(member_sig, CHECK_NULL);
2296   dest->obj_at_put(2, str());
2297   return (jobjectArray) JNIHandles::make_local(THREAD, dest());
2298 }
2299 JVM_END
2300 
2301 JVM_ENTRY(jint, JVM_ConstantPoolGetClassRefIndexAt(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_field_or_method()) {
2308     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2309   }
2310   return (jint) cp->uncached_klass_ref_index_at(index);
2311 }
2312 JVM_END
2313 
2314 JVM_ENTRY(jint, JVM_ConstantPoolGetNameAndTypeRefIndexAt(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_0);
2319   constantTag tag = cp->tag_at(index);
2320   if (!tag.is_invoke_dynamic() && !tag.is_field_or_method()) {
2321     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2322   }
2323   return (jint) cp->uncached_name_and_type_ref_index_at(index);
2324 }
2325 JVM_END
2326 
2327 JVM_ENTRY(jobjectArray, JVM_ConstantPoolGetNameAndTypeRefInfoAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2328 {
2329   JvmtiVMObjectAllocEventCollector oam;
2330   constantPoolHandle cp(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2331   bounds_check(cp, index, CHECK_NULL);
2332   constantTag tag = cp->tag_at(index);
2333   if (!tag.is_name_and_type()) {
2334     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2335   }
2336   Symbol* member_name = cp->symbol_at(cp->name_ref_index_at(index));
2337   Symbol* member_sig = cp->symbol_at(cp->signature_ref_index_at(index));
2338   objArrayOop dest_o = oopFactory::new_objArray(vmClasses::String_klass(), 2, CHECK_NULL);
2339   objArrayHandle dest(THREAD, dest_o);
2340   Handle str = java_lang_String::create_from_symbol(member_name, CHECK_NULL);
2341   dest->obj_at_put(0, str());
2342   str = java_lang_String::create_from_symbol(member_sig, CHECK_NULL);
2343   dest->obj_at_put(1, str());
2344   return (jobjectArray) JNIHandles::make_local(THREAD, dest());
2345 }
2346 JVM_END
2347 
2348 JVM_ENTRY(jint, JVM_ConstantPoolGetIntAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2349 {
2350   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2351   bounds_check(cp, index, CHECK_0);
2352   constantTag tag = cp->tag_at(index);
2353   if (!tag.is_int()) {
2354     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2355   }
2356   return cp->int_at(index);
2357 }
2358 JVM_END
2359 
2360 JVM_ENTRY(jlong, JVM_ConstantPoolGetLongAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2361 {
2362   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2363   bounds_check(cp, index, CHECK_(0L));
2364   constantTag tag = cp->tag_at(index);
2365   if (!tag.is_long()) {
2366     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2367   }
2368   return cp->long_at(index);
2369 }
2370 JVM_END
2371 
2372 JVM_ENTRY(jfloat, JVM_ConstantPoolGetFloatAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2373 {
2374   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2375   bounds_check(cp, index, CHECK_(0.0f));
2376   constantTag tag = cp->tag_at(index);
2377   if (!tag.is_float()) {
2378     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2379   }
2380   return cp->float_at(index);
2381 }
2382 JVM_END
2383 
2384 JVM_ENTRY(jdouble, JVM_ConstantPoolGetDoubleAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2385 {
2386   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2387   bounds_check(cp, index, CHECK_(0.0));
2388   constantTag tag = cp->tag_at(index);
2389   if (!tag.is_double()) {
2390     THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2391   }
2392   return cp->double_at(index);
2393 }
2394 JVM_END
2395 
2396 JVM_ENTRY(jstring, JVM_ConstantPoolGetStringAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2397 {
2398   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2399   bounds_check(cp, index, CHECK_NULL);
2400   constantTag tag = cp->tag_at(index);
2401   if (!tag.is_string()) {
2402     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2403   }
2404   oop str = cp->string_at(index, CHECK_NULL);
2405   return (jstring) JNIHandles::make_local(THREAD, str);
2406 }
2407 JVM_END
2408 
2409 JVM_ENTRY(jstring, JVM_ConstantPoolGetUTF8At(JNIEnv *env, jobject obj, jobject unused, jint index))
2410 {
2411   JvmtiVMObjectAllocEventCollector oam;
2412   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2413   bounds_check(cp, index, CHECK_NULL);
2414   constantTag tag = cp->tag_at(index);
2415   if (!tag.is_symbol()) {
2416     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Wrong type at constant pool index");
2417   }
2418   Symbol* sym = cp->symbol_at(index);
2419   Handle str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
2420   return (jstring) JNIHandles::make_local(THREAD, str());
2421 }
2422 JVM_END
2423 
2424 JVM_ENTRY(jbyte, JVM_ConstantPoolGetTagAt(JNIEnv *env, jobject obj, jobject unused, jint index))
2425 {
2426   constantPoolHandle cp = constantPoolHandle(THREAD, reflect_ConstantPool::get_cp(JNIHandles::resolve_non_null(obj)));
2427   bounds_check(cp, index, CHECK_0);
2428   constantTag tag = cp->tag_at(index);
2429   jbyte result = tag.value();
2430   // If returned tag values are not from the JVM spec, e.g. tags from 100 to 105,
2431   // they are changed to the corresponding tags from the JVM spec, so that java code in
2432   // sun.reflect.ConstantPool will return only tags from the JVM spec, not internal ones.
2433   if (tag.is_klass_or_reference()) {
2434       result = JVM_CONSTANT_Class;
2435   } else if (tag.is_string_index()) {
2436       result = JVM_CONSTANT_String;
2437   } else if (tag.is_method_type_in_error()) {
2438       result = JVM_CONSTANT_MethodType;
2439   } else if (tag.is_method_handle_in_error()) {
2440       result = JVM_CONSTANT_MethodHandle;
2441   } else if (tag.is_dynamic_constant_in_error()) {
2442       result = JVM_CONSTANT_Dynamic;
2443   }
2444   return result;
2445 }
2446 JVM_END
2447 
2448 // Assertion support. //////////////////////////////////////////////////////////
2449 
2450 JVM_ENTRY(jboolean, JVM_DesiredAssertionStatus(JNIEnv *env, jclass unused, jclass cls))
2451   assert(cls != nullptr, "bad class");
2452 
2453   oop r = JNIHandles::resolve(cls);
2454   assert(! java_lang_Class::is_primitive(r), "primitive classes not allowed");
2455   if (java_lang_Class::is_primitive(r)) return false;
2456 
2457   Klass* k = java_lang_Class::as_Klass(r);
2458   assert(k->is_instance_klass(), "must be an instance klass");
2459   if (!k->is_instance_klass()) return false;
2460 
2461   ResourceMark rm(THREAD);
2462   const char* name = k->name()->as_C_string();
2463   bool system_class = k->class_loader() == nullptr;
2464   return JavaAssertions::enabled(name, system_class);
2465 
2466 JVM_END
2467 
2468 
2469 // Return a new AssertionStatusDirectives object with the fields filled in with
2470 // command-line assertion arguments (i.e., -ea, -da).
2471 JVM_ENTRY(jobject, JVM_AssertionStatusDirectives(JNIEnv *env, jclass unused))
2472   JvmtiVMObjectAllocEventCollector oam;
2473   oop asd = JavaAssertions::createAssertionStatusDirectives(CHECK_NULL);
2474   return JNIHandles::make_local(THREAD, asd);
2475 JVM_END
2476 
2477 // Verification ////////////////////////////////////////////////////////////////////////////////
2478 
2479 // Reflection for the verifier /////////////////////////////////////////////////////////////////
2480 
2481 // RedefineClasses support: bug 6214132 caused verification to fail.
2482 // All functions from this section should call the jvmtiThreadSate function:
2483 //   Klass* class_to_verify_considering_redefinition(Klass* klass).
2484 // The function returns a Klass* of the _scratch_class if the verifier
2485 // was invoked in the middle of the class redefinition.
2486 // Otherwise it returns its argument value which is the _the_class Klass*.
2487 // Please, refer to the description in the jvmtiThreadState.hpp.
2488 
2489 JVM_ENTRY(jboolean, JVM_IsInterface(JNIEnv *env, jclass cls))
2490   oop mirror = JNIHandles::resolve_non_null(cls);
2491   if (java_lang_Class::is_primitive(mirror)) {
2492     return JNI_FALSE;
2493   }
2494   Klass* k = java_lang_Class::as_Klass(mirror);
2495   // This isn't necessary since answer is the same since redefinition
2496   // has already checked this matches for the scratch class.
2497   // k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2498   jboolean result = k->is_interface();
2499   assert(!result || k->is_instance_klass(),
2500          "all interfaces are instance types");
2501   return result;
2502 JVM_END
2503 
2504 
2505 JVM_ENTRY(const char*, JVM_GetClassNameUTF(JNIEnv *env, jclass cls))
2506   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2507   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2508   return k->name()->as_utf8();
2509 JVM_END
2510 
2511 
2512 JVM_ENTRY(void, JVM_GetClassCPTypes(JNIEnv *env, jclass cls, unsigned char *types))
2513   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2514   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2515   // types will have length zero if this is not an InstanceKlass
2516   // (length is determined by call to JVM_GetClassCPEntriesCount)
2517   if (k->is_instance_klass()) {
2518     ConstantPool* cp = InstanceKlass::cast(k)->constants();
2519     for (int index = cp->length() - 1; index >= 0; index--) {
2520       constantTag tag = cp->tag_at(index);
2521       types[index] = (tag.is_unresolved_klass()) ? (unsigned char) JVM_CONSTANT_Class : tag.value();
2522     }
2523   }
2524 JVM_END
2525 
2526 
2527 JVM_ENTRY(jint, JVM_GetClassCPEntriesCount(JNIEnv *env, jclass cls))
2528   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2529   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2530   return (!k->is_instance_klass()) ? 0 : InstanceKlass::cast(k)->constants()->length();
2531 JVM_END
2532 
2533 
2534 JVM_ENTRY(jint, JVM_GetClassFieldsCount(JNIEnv *env, jclass cls))
2535   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2536   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2537   return (!k->is_instance_klass()) ? 0 : InstanceKlass::cast(k)->java_fields_count();
2538 JVM_END
2539 
2540 
2541 JVM_ENTRY(jint, JVM_GetClassMethodsCount(JNIEnv *env, jclass cls))
2542   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2543   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2544   return (!k->is_instance_klass()) ? 0 : InstanceKlass::cast(k)->methods()->length();
2545 JVM_END
2546 
2547 
2548 // The following methods, used for the verifier, are never called with
2549 // array klasses, so a direct cast to InstanceKlass is safe.
2550 // Typically, these methods are called in a loop with bounds determined
2551 // by the results of JVM_GetClass{Fields,Methods}Count, which return
2552 // zero for arrays.
2553 JVM_ENTRY(void, JVM_GetMethodIxExceptionIndexes(JNIEnv *env, jclass cls, jint method_index, unsigned short *exceptions))
2554   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2555   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2556   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2557   int length = method->checked_exceptions_length();
2558   if (length > 0) {
2559     CheckedExceptionElement* table= method->checked_exceptions_start();
2560     for (int i = 0; i < length; i++) {
2561       exceptions[i] = table[i].class_cp_index;
2562     }
2563   }
2564 JVM_END
2565 
2566 
2567 JVM_ENTRY(jint, JVM_GetMethodIxExceptionsCount(JNIEnv *env, jclass cls, jint method_index))
2568   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2569   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2570   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2571   return method->checked_exceptions_length();
2572 JVM_END
2573 
2574 
2575 JVM_ENTRY(void, JVM_GetMethodIxByteCode(JNIEnv *env, jclass cls, jint method_index, unsigned char *code))
2576   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2577   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2578   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2579   memcpy(code, method->code_base(), method->code_size());
2580 JVM_END
2581 
2582 
2583 JVM_ENTRY(jint, JVM_GetMethodIxByteCodeLength(JNIEnv *env, jclass cls, jint method_index))
2584   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2585   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2586   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2587   return method->code_size();
2588 JVM_END
2589 
2590 
2591 JVM_ENTRY(void, JVM_GetMethodIxExceptionTableEntry(JNIEnv *env, jclass cls, jint method_index, jint entry_index, JVM_ExceptionTableEntryType *entry))
2592   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2593   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2594   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2595   ExceptionTable extable(method);
2596   entry->start_pc   = extable.start_pc(entry_index);
2597   entry->end_pc     = extable.end_pc(entry_index);
2598   entry->handler_pc = extable.handler_pc(entry_index);
2599   entry->catchType  = extable.catch_type_index(entry_index);
2600 JVM_END
2601 
2602 
2603 JVM_ENTRY(jint, JVM_GetMethodIxExceptionTableLength(JNIEnv *env, jclass cls, int method_index))
2604   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2605   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2606   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2607   return method->exception_table_length();
2608 JVM_END
2609 
2610 
2611 JVM_ENTRY(jint, JVM_GetMethodIxModifiers(JNIEnv *env, jclass cls, int method_index))
2612   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2613   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2614   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2615   return method->access_flags().as_method_flags();
2616 JVM_END
2617 
2618 
2619 JVM_ENTRY(jint, JVM_GetFieldIxModifiers(JNIEnv *env, jclass cls, int field_index))
2620   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2621   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2622   return InstanceKlass::cast(k)->field_access_flags(field_index);
2623 JVM_END
2624 
2625 
2626 JVM_ENTRY(jint, JVM_GetMethodIxLocalsCount(JNIEnv *env, jclass cls, int method_index))
2627   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2628   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2629   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2630   return method->max_locals();
2631 JVM_END
2632 
2633 
2634 JVM_ENTRY(jint, JVM_GetMethodIxArgsSize(JNIEnv *env, jclass cls, int method_index))
2635   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2636   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2637   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2638   return method->size_of_parameters();
2639 JVM_END
2640 
2641 
2642 JVM_ENTRY(jint, JVM_GetMethodIxMaxStack(JNIEnv *env, jclass cls, int method_index))
2643   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2644   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2645   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2646   return method->verifier_max_stack();
2647 JVM_END
2648 
2649 
2650 JVM_ENTRY(jboolean, JVM_IsConstructorIx(JNIEnv *env, jclass cls, int method_index))
2651   ResourceMark rm(THREAD);
2652   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2653   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2654   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2655   return method->is_object_constructor();
2656 JVM_END
2657 
2658 
2659 JVM_ENTRY(jboolean, JVM_IsVMGeneratedMethodIx(JNIEnv *env, jclass cls, int method_index))
2660   ResourceMark rm(THREAD);
2661   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2662   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2663   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2664   return method->is_overpass();
2665 JVM_END
2666 
2667 JVM_ENTRY(const char*, JVM_GetMethodIxNameUTF(JNIEnv *env, jclass cls, jint method_index))
2668   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2669   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2670   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2671   return method->name()->as_utf8();
2672 JVM_END
2673 
2674 
2675 JVM_ENTRY(const char*, JVM_GetMethodIxSignatureUTF(JNIEnv *env, jclass cls, jint method_index))
2676   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2677   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2678   Method* method = InstanceKlass::cast(k)->methods()->at(method_index);
2679   return method->signature()->as_utf8();
2680 JVM_END
2681 
2682 /**
2683  * All of these JVM_GetCP-xxx methods are used by the old verifier to
2684  * read entries in the constant pool.  Since the old verifier always
2685  * works on a copy of the code, it will not see any rewriting that
2686  * may possibly occur in the middle of verification.  So it is important
2687  * that nothing it calls tries to use the cpCache instead of the raw
2688  * constant pool, so we must use cp->uncached_x methods when appropriate.
2689  */
2690 JVM_ENTRY(const char*, JVM_GetCPFieldNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2691   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2692   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2693   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2694   switch (cp->tag_at(cp_index).value()) {
2695     case JVM_CONSTANT_Fieldref:
2696       return cp->uncached_name_ref_at(cp_index)->as_utf8();
2697     default:
2698       fatal("JVM_GetCPFieldNameUTF: illegal constant");
2699   }
2700   ShouldNotReachHere();
2701   return nullptr;
2702 JVM_END
2703 
2704 
2705 JVM_ENTRY(const char*, JVM_GetCPMethodNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2706   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2707   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2708   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2709   switch (cp->tag_at(cp_index).value()) {
2710     case JVM_CONSTANT_InterfaceMethodref:
2711     case JVM_CONSTANT_Methodref:
2712       return cp->uncached_name_ref_at(cp_index)->as_utf8();
2713     default:
2714       fatal("JVM_GetCPMethodNameUTF: illegal constant");
2715   }
2716   ShouldNotReachHere();
2717   return nullptr;
2718 JVM_END
2719 
2720 
2721 JVM_ENTRY(const char*, JVM_GetCPMethodSignatureUTF(JNIEnv *env, jclass cls, jint cp_index))
2722   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2723   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2724   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2725   switch (cp->tag_at(cp_index).value()) {
2726     case JVM_CONSTANT_InterfaceMethodref:
2727     case JVM_CONSTANT_Methodref:
2728       return cp->uncached_signature_ref_at(cp_index)->as_utf8();
2729     default:
2730       fatal("JVM_GetCPMethodSignatureUTF: illegal constant");
2731   }
2732   ShouldNotReachHere();
2733   return nullptr;
2734 JVM_END
2735 
2736 
2737 JVM_ENTRY(const char*, JVM_GetCPFieldSignatureUTF(JNIEnv *env, jclass cls, jint cp_index))
2738   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2739   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2740   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2741   switch (cp->tag_at(cp_index).value()) {
2742     case JVM_CONSTANT_Fieldref:
2743       return cp->uncached_signature_ref_at(cp_index)->as_utf8();
2744     default:
2745       fatal("JVM_GetCPFieldSignatureUTF: illegal constant");
2746   }
2747   ShouldNotReachHere();
2748   return nullptr;
2749 JVM_END
2750 
2751 
2752 JVM_ENTRY(const char*, JVM_GetCPClassNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2753   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2754   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2755   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2756   Symbol* classname = cp->klass_name_at(cp_index);
2757   return classname->as_utf8();
2758 JVM_END
2759 
2760 
2761 JVM_ENTRY(const char*, JVM_GetCPFieldClassNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2762   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2763   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2764   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2765   switch (cp->tag_at(cp_index).value()) {
2766     case JVM_CONSTANT_Fieldref: {
2767       int class_index = cp->uncached_klass_ref_index_at(cp_index);
2768       Symbol* classname = cp->klass_name_at(class_index);
2769       return classname->as_utf8();
2770     }
2771     default:
2772       fatal("JVM_GetCPFieldClassNameUTF: illegal constant");
2773   }
2774   ShouldNotReachHere();
2775   return nullptr;
2776 JVM_END
2777 
2778 
2779 JVM_ENTRY(const char*, JVM_GetCPMethodClassNameUTF(JNIEnv *env, jclass cls, jint cp_index))
2780   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2781   k = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2782   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2783   switch (cp->tag_at(cp_index).value()) {
2784     case JVM_CONSTANT_Methodref:
2785     case JVM_CONSTANT_InterfaceMethodref: {
2786       int class_index = cp->uncached_klass_ref_index_at(cp_index);
2787       Symbol* classname = cp->klass_name_at(class_index);
2788       return classname->as_utf8();
2789     }
2790     default:
2791       fatal("JVM_GetCPMethodClassNameUTF: illegal constant");
2792   }
2793   ShouldNotReachHere();
2794   return nullptr;
2795 JVM_END
2796 
2797 
2798 JVM_ENTRY(jint, JVM_GetCPFieldModifiers(JNIEnv *env, jclass cls, int cp_index, jclass called_cls))
2799   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2800   Klass* k_called = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(called_cls));
2801   k        = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2802   k_called = JvmtiThreadState::class_to_verify_considering_redefinition(k_called, thread);
2803   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2804   ConstantPool* cp_called = InstanceKlass::cast(k_called)->constants();
2805   switch (cp->tag_at(cp_index).value()) {
2806     case JVM_CONSTANT_Fieldref: {
2807       Symbol* name      = cp->uncached_name_ref_at(cp_index);
2808       Symbol* signature = cp->uncached_signature_ref_at(cp_index);
2809       InstanceKlass* ik = InstanceKlass::cast(k_called);
2810       for (JavaFieldStream fs(ik); !fs.done(); fs.next()) {
2811         if (fs.name() == name && fs.signature() == signature) {
2812           return fs.access_flags().as_field_flags();
2813         }
2814       }
2815       return -1;
2816     }
2817     default:
2818       fatal("JVM_GetCPFieldModifiers: illegal constant");
2819   }
2820   ShouldNotReachHere();
2821   return 0;
2822 JVM_END
2823 
2824 
2825 JVM_ENTRY(jint, JVM_GetCPMethodModifiers(JNIEnv *env, jclass cls, int cp_index, jclass called_cls))
2826   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(cls));
2827   Klass* k_called = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(called_cls));
2828   k        = JvmtiThreadState::class_to_verify_considering_redefinition(k, thread);
2829   k_called = JvmtiThreadState::class_to_verify_considering_redefinition(k_called, thread);
2830   ConstantPool* cp = InstanceKlass::cast(k)->constants();
2831   switch (cp->tag_at(cp_index).value()) {
2832     case JVM_CONSTANT_Methodref:
2833     case JVM_CONSTANT_InterfaceMethodref: {
2834       Symbol* name      = cp->uncached_name_ref_at(cp_index);
2835       Symbol* signature = cp->uncached_signature_ref_at(cp_index);
2836       Array<Method*>* methods = InstanceKlass::cast(k_called)->methods();
2837       int methods_count = methods->length();
2838       for (int i = 0; i < methods_count; i++) {
2839         Method* method = methods->at(i);
2840         if (method->name() == name && method->signature() == signature) {
2841             return method->access_flags().as_method_flags();
2842         }
2843       }
2844       return -1;
2845     }
2846     default:
2847       fatal("JVM_GetCPMethodModifiers: illegal constant");
2848   }
2849   ShouldNotReachHere();
2850   return 0;
2851 JVM_END
2852 
2853 
2854 // Misc //////////////////////////////////////////////////////////////////////////////////////////////
2855 
2856 JVM_LEAF(void, JVM_ReleaseUTF(const char *utf))
2857   // So long as UTF8::convert_to_utf8 returns resource strings, we don't have to do anything
2858 JVM_END
2859 
2860 
2861 JVM_ENTRY(jboolean, JVM_IsSameClassPackage(JNIEnv *env, jclass class1, jclass class2))
2862   oop class1_mirror = JNIHandles::resolve_non_null(class1);
2863   oop class2_mirror = JNIHandles::resolve_non_null(class2);
2864   Klass* klass1 = java_lang_Class::as_Klass(class1_mirror);
2865   Klass* klass2 = java_lang_Class::as_Klass(class2_mirror);
2866   return (jboolean) Reflection::is_same_class_package(klass1, klass2);
2867 JVM_END
2868 
2869 // Printing support //////////////////////////////////////////////////
2870 extern "C" {
2871 
2872 ATTRIBUTE_PRINTF(3, 0)
2873 int jio_vsnprintf(char *str, size_t count, const char *fmt, va_list args) {
2874   // Reject count values that are negative signed values converted to
2875   // unsigned; see bug 4399518, 4417214
2876   if ((intptr_t)count <= 0) return -1;
2877 
2878   int result = os::vsnprintf(str, count, fmt, args);
2879   if (result > 0 && (size_t)result >= count) {
2880     result = -1;
2881   }
2882 
2883   return result;
2884 }
2885 
2886 ATTRIBUTE_PRINTF(3, 4)
2887 int jio_snprintf(char *str, size_t count, const char *fmt, ...) {
2888   va_list args;
2889   int len;
2890   va_start(args, fmt);
2891   len = jio_vsnprintf(str, count, fmt, args);
2892   va_end(args);
2893   return len;
2894 }
2895 
2896 ATTRIBUTE_PRINTF(2, 3)
2897 int jio_fprintf(FILE* f, const char *fmt, ...) {
2898   int len;
2899   va_list args;
2900   va_start(args, fmt);
2901   len = jio_vfprintf(f, fmt, args);
2902   va_end(args);
2903   return len;
2904 }
2905 
2906 ATTRIBUTE_PRINTF(2, 0)
2907 int jio_vfprintf(FILE* f, const char *fmt, va_list args) {
2908   if (Arguments::vfprintf_hook() != nullptr) {
2909      return Arguments::vfprintf_hook()(f, fmt, args);
2910   } else {
2911     return vfprintf(f, fmt, args);
2912   }
2913 }
2914 
2915 ATTRIBUTE_PRINTF(1, 2)
2916 JNIEXPORT int jio_printf(const char *fmt, ...) {
2917   int len;
2918   va_list args;
2919   va_start(args, fmt);
2920   len = jio_vfprintf(defaultStream::output_stream(), fmt, args);
2921   va_end(args);
2922   return len;
2923 }
2924 
2925 // HotSpot specific jio method
2926 void jio_print(const char* s, size_t len) {
2927   // Try to make this function as atomic as possible.
2928   if (Arguments::vfprintf_hook() != nullptr) {
2929     jio_fprintf(defaultStream::output_stream(), "%.*s", (int)len, s);
2930   } else {
2931     // Make an unused local variable to avoid warning from gcc compiler.
2932     bool dummy = os::write(defaultStream::output_fd(), s, len);
2933   }
2934 }
2935 
2936 } // Extern C
2937 
2938 // java.lang.Thread //////////////////////////////////////////////////////////////////////////////
2939 
2940 // In most of the JVM thread support functions we need to access the
2941 // thread through a ThreadsListHandle to prevent it from exiting and
2942 // being reclaimed while we try to operate on it. The exceptions to this
2943 // rule are when operating on the current thread, or if the monitor of
2944 // the target java.lang.Thread is locked at the Java level - in both
2945 // cases the target cannot exit.
2946 
2947 static void thread_entry(JavaThread* thread, TRAPS) {
2948   HandleMark hm(THREAD);
2949   Handle obj(THREAD, thread->threadObj());
2950   JavaValue result(T_VOID);
2951   JavaCalls::call_virtual(&result,
2952                           obj,
2953                           vmClasses::Thread_klass(),
2954                           vmSymbols::run_method_name(),
2955                           vmSymbols::void_method_signature(),
2956                           THREAD);
2957 }
2958 
2959 
2960 JVM_ENTRY(void, JVM_StartThread(JNIEnv* env, jobject jthread))
2961 #if INCLUDE_CDS
2962   if (CDSConfig::allow_only_single_java_thread()) {
2963     // During java -Xshare:dump, if we allow multiple Java threads to
2964     // execute in parallel, symbols and classes may be loaded in
2965     // random orders which will make the resulting CDS archive
2966     // non-deterministic.
2967     //
2968     // Lucikly, during java -Xshare:dump, it's important to run only
2969     // the code in the main Java thread (which is NOT started here) that
2970     // creates the module graph, etc. It's safe to not start the other
2971     // threads which are launched by class static initializers
2972     // (ReferenceHandler, FinalizerThread and CleanerImpl).
2973     if (log_is_enabled(Info, cds)) {
2974       ResourceMark rm;
2975       oop t = JNIHandles::resolve_non_null(jthread);
2976       log_info(cds)("JVM_StartThread() ignored: %s", t->klass()->external_name());
2977     }
2978     return;
2979   }
2980 #endif
2981   JavaThread *native_thread = nullptr;
2982 
2983   // We cannot hold the Threads_lock when we throw an exception,
2984   // due to rank ordering issues. Example:  we might need to grab the
2985   // Heap_lock while we construct the exception.
2986   bool throw_illegal_thread_state = false;
2987 
2988   // We must release the Threads_lock before we can post a jvmti event
2989   // in Thread::start.
2990   {
2991     ConditionalMutexLocker throttle_ml(ThreadsLockThrottle_lock, UseThreadsLockThrottleLock);
2992     // Ensure that the C++ Thread and OSThread structures aren't freed before
2993     // we operate.
2994     MutexLocker ml(Threads_lock);
2995 
2996     // Since JDK 5 the java.lang.Thread threadStatus is used to prevent
2997     // re-starting an already started thread, so we should usually find
2998     // that the JavaThread is null. However for a JNI attached thread
2999     // there is a small window between the Thread object being created
3000     // (with its JavaThread set) and the update to its threadStatus, so we
3001     // have to check for this
3002     if (java_lang_Thread::thread(JNIHandles::resolve_non_null(jthread)) != nullptr) {
3003       throw_illegal_thread_state = true;
3004     } else {
3005       jlong size =
3006              java_lang_Thread::stackSize(JNIHandles::resolve_non_null(jthread));
3007       // Allocate the C++ Thread structure and create the native thread.  The
3008       // stack size retrieved from java is 64-bit signed, but the constructor takes
3009       // size_t (an unsigned type), which may be 32 or 64-bit depending on the platform.
3010       //  - Avoid truncating on 32-bit platforms if size is greater than UINT_MAX.
3011       //  - Avoid passing negative values which would result in really large stacks.
3012       NOT_LP64(if (size > SIZE_MAX) size = SIZE_MAX;)
3013       size_t sz = size > 0 ? (size_t) size : 0;
3014       native_thread = new JavaThread(&thread_entry, sz);
3015 
3016       // At this point it may be possible that no osthread was created for the
3017       // JavaThread due to lack of memory. Check for this situation and throw
3018       // an exception if necessary. Eventually we may want to change this so
3019       // that we only grab the lock if the thread was created successfully -
3020       // then we can also do this check and throw the exception in the
3021       // JavaThread constructor.
3022       if (native_thread->osthread() != nullptr) {
3023         // Note: the current thread is not being used within "prepare".
3024         native_thread->prepare(jthread);
3025       }
3026     }
3027   }
3028 
3029   if (throw_illegal_thread_state) {
3030     THROW(vmSymbols::java_lang_IllegalThreadStateException());
3031   }
3032 
3033   assert(native_thread != nullptr, "Starting null thread?");
3034 
3035   if (native_thread->osthread() == nullptr) {
3036     ResourceMark rm(thread);
3037     log_warning(os, thread)("Failed to start the native thread for java.lang.Thread \"%s\"",
3038                             JavaThread::name_for(JNIHandles::resolve_non_null(jthread)));
3039     // No one should hold a reference to the 'native_thread'.
3040     native_thread->smr_delete();
3041     if (JvmtiExport::should_post_resource_exhausted()) {
3042       JvmtiExport::post_resource_exhausted(
3043         JVMTI_RESOURCE_EXHAUSTED_OOM_ERROR | JVMTI_RESOURCE_EXHAUSTED_THREADS,
3044         os::native_thread_creation_failed_msg());
3045     }
3046     THROW_MSG(vmSymbols::java_lang_OutOfMemoryError(),
3047               os::native_thread_creation_failed_msg());
3048   }
3049 
3050   JFR_ONLY(Jfr::on_java_thread_start(thread, native_thread);)
3051 
3052   Thread::start(native_thread);
3053 
3054 JVM_END
3055 
3056 
3057 JVM_ENTRY(void, JVM_SetThreadPriority(JNIEnv* env, jobject jthread, jint prio))
3058   ThreadsListHandle tlh(thread);
3059   oop java_thread = nullptr;
3060   JavaThread* receiver = nullptr;
3061   bool is_alive = tlh.cv_internal_thread_to_JavaThread(jthread, &receiver, &java_thread);
3062   java_lang_Thread::set_priority(java_thread, (ThreadPriority)prio);
3063 
3064   if (is_alive) {
3065     // jthread refers to a live JavaThread.
3066     Thread::set_priority(receiver, (ThreadPriority)prio);
3067   }
3068   // Implied else: If the JavaThread hasn't started yet, then the
3069   // priority set in the java.lang.Thread object above will be pushed
3070   // down when it does start.
3071 JVM_END
3072 
3073 
3074 JVM_LEAF(void, JVM_Yield(JNIEnv *env, jclass threadClass))
3075   HOTSPOT_THREAD_YIELD();
3076   os::naked_yield();
3077 JVM_END
3078 
3079 JVM_ENTRY(void, JVM_SleepNanos(JNIEnv* env, jclass threadClass, jlong nanos))
3080   if (nanos < 0) {
3081     THROW_MSG(vmSymbols::java_lang_IllegalArgumentException(), "nanosecond timeout value out of range");
3082   }
3083 
3084   if (thread->is_interrupted(true) && !HAS_PENDING_EXCEPTION) {
3085     THROW_MSG(vmSymbols::java_lang_InterruptedException(), "sleep interrupted");
3086   }
3087 
3088   // Save current thread state and restore it at the end of this block.
3089   // And set new thread state to SLEEPING.
3090   JavaThreadSleepState jtss(thread);
3091 
3092   HOTSPOT_THREAD_SLEEP_BEGIN(nanos / NANOSECS_PER_MILLISEC);
3093 
3094   if (nanos == 0) {
3095     os::naked_yield();
3096   } else {
3097     ThreadState old_state = thread->osthread()->get_state();
3098     thread->osthread()->set_state(SLEEPING);
3099     if (!thread->sleep_nanos(nanos)) { // interrupted
3100       // An asynchronous exception could have been thrown on
3101       // us while we were sleeping. We do not overwrite those.
3102       if (!HAS_PENDING_EXCEPTION) {
3103         HOTSPOT_THREAD_SLEEP_END(1);
3104 
3105         // TODO-FIXME: THROW_MSG returns which means we will not call set_state()
3106         // to properly restore the thread state.  That's likely wrong.
3107         THROW_MSG(vmSymbols::java_lang_InterruptedException(), "sleep interrupted");
3108       }
3109     }
3110     thread->osthread()->set_state(old_state);
3111   }
3112   HOTSPOT_THREAD_SLEEP_END(0);
3113 JVM_END
3114 
3115 JVM_ENTRY(jobject, JVM_CurrentCarrierThread(JNIEnv* env, jclass threadClass))
3116   oop jthread = thread->threadObj();
3117   assert(jthread != nullptr, "no current carrier thread!");
3118   return JNIHandles::make_local(THREAD, jthread);
3119 JVM_END
3120 
3121 JVM_ENTRY(jobject, JVM_CurrentThread(JNIEnv* env, jclass threadClass))
3122   oop theThread = thread->vthread();
3123   assert(theThread != (oop)nullptr, "no current thread!");
3124   return JNIHandles::make_local(THREAD, theThread);
3125 JVM_END
3126 
3127 JVM_ENTRY(void, JVM_SetCurrentThread(JNIEnv* env, jobject thisThread,
3128                                      jobject theThread))
3129   oop threadObj = JNIHandles::resolve(theThread);
3130   thread->set_vthread(threadObj);
3131 
3132   // Set _monitor_owner_id of new current Thread
3133   thread->set_monitor_owner_id(java_lang_Thread::thread_id(threadObj));
3134 
3135   JFR_ONLY(Jfr::on_set_current_thread(thread, threadObj);)
3136 JVM_END
3137 
3138 JVM_ENTRY(jlong, JVM_GetNextThreadIdOffset(JNIEnv* env, jclass threadClass))
3139   return ThreadIdentifier::unsafe_offset();
3140 JVM_END
3141 
3142 JVM_ENTRY(void, JVM_Interrupt(JNIEnv* env, jobject jthread))
3143   ThreadsListHandle tlh(thread);
3144   JavaThread* receiver = nullptr;
3145   bool is_alive = tlh.cv_internal_thread_to_JavaThread(jthread, &receiver, nullptr);
3146   if (is_alive) {
3147     // jthread refers to a live JavaThread.
3148     receiver->interrupt();
3149   }
3150 JVM_END
3151 
3152 // Return true iff the current thread has locked the object passed in
3153 
3154 JVM_ENTRY(jboolean, JVM_HoldsLock(JNIEnv* env, jclass threadClass, jobject obj))
3155   if (obj == nullptr) {
3156     THROW_(vmSymbols::java_lang_NullPointerException(), JNI_FALSE);
3157   }
3158   Handle h_obj(THREAD, JNIHandles::resolve(obj));
3159   return ObjectSynchronizer::current_thread_holds_lock(thread, h_obj);
3160 JVM_END
3161 
3162 JVM_ENTRY(jobject, JVM_GetStackTrace(JNIEnv *env, jobject jthread))
3163   oop trace = java_lang_Thread::async_get_stack_trace(JNIHandles::resolve(jthread), THREAD);
3164   return JNIHandles::make_local(THREAD, trace);
3165 JVM_END
3166 
3167 JVM_ENTRY(void, JVM_SetNativeThreadName(JNIEnv* env, jobject jthread, jstring name))
3168   // We don't use a ThreadsListHandle here because the current thread
3169   // must be alive.
3170   oop java_thread = JNIHandles::resolve_non_null(jthread);
3171   JavaThread* thr = java_lang_Thread::thread(java_thread);
3172   if (thread == thr && !thr->has_attached_via_jni()) {
3173     // Thread naming is only supported for the current thread and
3174     // we don't set the name of an attached thread to avoid stepping
3175     // on other programs.
3176     ResourceMark rm(thread);
3177     const char *thread_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
3178     os::set_native_thread_name(thread_name);
3179   }
3180 JVM_END
3181 
3182 JVM_ENTRY(jobject, JVM_ScopedValueCache(JNIEnv* env, jclass threadClass))
3183   oop theCache = thread->scopedValueCache();
3184   return JNIHandles::make_local(THREAD, theCache);
3185 JVM_END
3186 
3187 JVM_ENTRY(void, JVM_SetScopedValueCache(JNIEnv* env, jclass threadClass,
3188                                        jobject theCache))
3189   arrayOop objs = arrayOop(JNIHandles::resolve(theCache));
3190   thread->set_scopedValueCache(objs);
3191 JVM_END
3192 
3193 
3194 // java.lang.Package ////////////////////////////////////////////////////////////////
3195 
3196 
3197 JVM_ENTRY(jstring, JVM_GetSystemPackage(JNIEnv *env, jstring name))
3198   ResourceMark rm(THREAD);
3199   JvmtiVMObjectAllocEventCollector oam;
3200   char* str = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
3201   oop result = ClassLoader::get_system_package(str, CHECK_NULL);
3202 return (jstring) JNIHandles::make_local(THREAD, result);
3203 JVM_END
3204 
3205 
3206 JVM_ENTRY(jobjectArray, JVM_GetSystemPackages(JNIEnv *env))
3207   JvmtiVMObjectAllocEventCollector oam;
3208   objArrayOop result = ClassLoader::get_system_packages(CHECK_NULL);
3209   return (jobjectArray) JNIHandles::make_local(THREAD, result);
3210 JVM_END
3211 
3212 
3213 // java.lang.ref.Reference ///////////////////////////////////////////////////////////////
3214 
3215 
3216 JVM_ENTRY(jobject, JVM_GetAndClearReferencePendingList(JNIEnv* env))
3217   MonitorLocker ml(Heap_lock);
3218   oop ref = Universe::reference_pending_list();
3219   if (ref != nullptr) {
3220     Universe::clear_reference_pending_list();
3221   }
3222   return JNIHandles::make_local(THREAD, ref);
3223 JVM_END
3224 
3225 JVM_ENTRY(jboolean, JVM_HasReferencePendingList(JNIEnv* env))
3226   MonitorLocker ml(Heap_lock);
3227   return Universe::has_reference_pending_list();
3228 JVM_END
3229 
3230 JVM_ENTRY(void, JVM_WaitForReferencePendingList(JNIEnv* env))
3231   MonitorLocker ml(Heap_lock);
3232   while (!Universe::has_reference_pending_list()) {
3233     ml.wait();
3234   }
3235 JVM_END
3236 
3237 JVM_ENTRY(jboolean, JVM_ReferenceRefersTo(JNIEnv* env, jobject ref, jobject o))
3238   oop ref_oop = JNIHandles::resolve_non_null(ref);
3239   // PhantomReference has it's own implementation of refersTo().
3240   // See: JVM_PhantomReferenceRefersTo
3241   assert(!java_lang_ref_Reference::is_phantom(ref_oop), "precondition");
3242   oop referent = java_lang_ref_Reference::weak_referent_no_keepalive(ref_oop);
3243   return referent == JNIHandles::resolve(o);
3244 JVM_END
3245 
3246 JVM_ENTRY(void, JVM_ReferenceClear(JNIEnv* env, jobject ref))
3247   oop ref_oop = JNIHandles::resolve_non_null(ref);
3248   // FinalReference has it's own implementation of clear().
3249   assert(!java_lang_ref_Reference::is_final(ref_oop), "precondition");
3250   if (java_lang_ref_Reference::unknown_referent_no_keepalive(ref_oop) == nullptr) {
3251     // If the referent has already been cleared then done.
3252     // However, if the referent is dead but has not yet been cleared by
3253     // concurrent reference processing, it should NOT be cleared here.
3254     // Instead, clearing should be left to the GC.  Clearing it here could
3255     // detectably lose an expected notification, which is impossible with
3256     // STW reference processing.  The clearing in enqueue() doesn't have
3257     // this problem, since the enqueue covers the notification, but it's not
3258     // worth the effort to handle that case specially.
3259     return;
3260   }
3261   java_lang_ref_Reference::clear_referent(ref_oop);
3262 JVM_END
3263 
3264 
3265 // java.lang.ref.PhantomReference //////////////////////////////////////////////////
3266 
3267 
3268 JVM_ENTRY(jboolean, JVM_PhantomReferenceRefersTo(JNIEnv* env, jobject ref, jobject o))
3269   oop ref_oop = JNIHandles::resolve_non_null(ref);
3270   oop referent = java_lang_ref_Reference::phantom_referent_no_keepalive(ref_oop);
3271   return referent == JNIHandles::resolve(o);
3272 JVM_END
3273 
3274 
3275 // ObjectInputStream ///////////////////////////////////////////////////////////////
3276 
3277 // Return the first user-defined class loader up the execution stack, or null
3278 // if only code from the bootstrap or platform class loader is on the stack.
3279 
3280 JVM_ENTRY(jobject, JVM_LatestUserDefinedLoader(JNIEnv *env))
3281   for (vframeStream vfst(thread); !vfst.at_end(); vfst.next()) {
3282     InstanceKlass* ik = vfst.method()->method_holder();
3283     oop loader = ik->class_loader();
3284     if (loader != nullptr && !SystemDictionary::is_platform_class_loader(loader)) {
3285       return JNIHandles::make_local(THREAD, loader);
3286     }
3287   }
3288   return nullptr;
3289 JVM_END
3290 
3291 
3292 // Array ///////////////////////////////////////////////////////////////////////////////////////////
3293 
3294 
3295 // resolve array handle and check arguments
3296 static inline arrayOop check_array(JNIEnv *env, jobject arr, bool type_array_only, TRAPS) {
3297   if (arr == nullptr) {
3298     THROW_NULL(vmSymbols::java_lang_NullPointerException());
3299   }
3300   oop a = JNIHandles::resolve_non_null(arr);
3301   if (!a->is_array()) {
3302     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Argument is not an array");
3303   } else if (type_array_only && !a->is_typeArray()) {
3304     THROW_MSG_NULL(vmSymbols::java_lang_IllegalArgumentException(), "Argument is not an array of primitive type");
3305   }
3306   return arrayOop(a);
3307 }
3308 
3309 
3310 JVM_ENTRY(jint, JVM_GetArrayLength(JNIEnv *env, jobject arr))
3311   arrayOop a = check_array(env, arr, false, CHECK_0);
3312   return a->length();
3313 JVM_END
3314 
3315 
3316 JVM_ENTRY(jobject, JVM_GetArrayElement(JNIEnv *env, jobject arr, jint index))
3317   JvmtiVMObjectAllocEventCollector oam;
3318   arrayOop a = check_array(env, arr, false, CHECK_NULL);
3319   jvalue value;
3320   BasicType type = Reflection::array_get(&value, a, index, CHECK_NULL);
3321   oop box = Reflection::box(&value, type, CHECK_NULL);
3322   return JNIHandles::make_local(THREAD, box);
3323 JVM_END
3324 
3325 
3326 JVM_ENTRY(jvalue, JVM_GetPrimitiveArrayElement(JNIEnv *env, jobject arr, jint index, jint wCode))
3327   jvalue value;
3328   value.i = 0; // to initialize value before getting used in CHECK
3329   arrayOop a = check_array(env, arr, true, CHECK_(value));
3330   assert(a->is_typeArray(), "just checking");
3331   BasicType type = Reflection::array_get(&value, a, index, CHECK_(value));
3332   BasicType wide_type = (BasicType) wCode;
3333   if (type != wide_type) {
3334     Reflection::widen(&value, type, wide_type, CHECK_(value));
3335   }
3336   return value;
3337 JVM_END
3338 
3339 
3340 JVM_ENTRY(void, JVM_SetArrayElement(JNIEnv *env, jobject arr, jint index, jobject val))
3341   arrayOop a = check_array(env, arr, false, CHECK);
3342   oop box = JNIHandles::resolve(val);
3343   jvalue value;
3344   value.i = 0; // to initialize value before getting used in CHECK
3345   BasicType value_type;
3346   if (a->is_objArray()) {
3347     // Make sure we do no unbox e.g. java/lang/Integer instances when storing into an object array
3348     value_type = Reflection::unbox_for_regular_object(box, &value);
3349   } else {
3350     value_type = Reflection::unbox_for_primitive(box, &value, CHECK);
3351   }
3352   Reflection::array_set(&value, a, index, value_type, CHECK);
3353 JVM_END
3354 
3355 
3356 JVM_ENTRY(void, JVM_SetPrimitiveArrayElement(JNIEnv *env, jobject arr, jint index, jvalue v, unsigned char vCode))
3357   arrayOop a = check_array(env, arr, true, CHECK);
3358   assert(a->is_typeArray(), "just checking");
3359   BasicType value_type = (BasicType) vCode;
3360   Reflection::array_set(&v, a, index, value_type, CHECK);
3361 JVM_END
3362 
3363 
3364 JVM_ENTRY(jobject, JVM_NewArray(JNIEnv *env, jclass eltClass, jint length))
3365   JvmtiVMObjectAllocEventCollector oam;
3366   oop element_mirror = JNIHandles::resolve(eltClass);
3367   oop result = Reflection::reflect_new_array(element_mirror, length, CHECK_NULL);
3368   return JNIHandles::make_local(THREAD, result);
3369 JVM_END
3370 
3371 
3372 JVM_ENTRY(jobject, JVM_NewMultiArray(JNIEnv *env, jclass eltClass, jintArray dim))
3373   JvmtiVMObjectAllocEventCollector oam;
3374   arrayOop dim_array = check_array(env, dim, true, CHECK_NULL);
3375   oop element_mirror = JNIHandles::resolve(eltClass);
3376   assert(dim_array->is_typeArray(), "just checking");
3377   oop result = Reflection::reflect_new_multi_array(element_mirror, typeArrayOop(dim_array), CHECK_NULL);
3378   return JNIHandles::make_local(THREAD, result);
3379 JVM_END
3380 
3381 
3382 // Library support ///////////////////////////////////////////////////////////////////////////
3383 
3384 JVM_LEAF(void*, JVM_LoadZipLibrary())
3385   return ZipLibrary::handle();
3386 JVM_END
3387 
3388 JVM_ENTRY_NO_ENV(void*, JVM_LoadLibrary(const char* name, jboolean throwException))
3389   //%note jvm_ct
3390   char ebuf[1024];
3391   void *load_result;
3392   {
3393     ThreadToNativeFromVM ttnfvm(thread);
3394     load_result = os::dll_load(name, ebuf, sizeof ebuf);
3395   }
3396   if (load_result == nullptr) {
3397     if (throwException) {
3398       char msg[1024];
3399       jio_snprintf(msg, sizeof msg, "%s: %s", name, ebuf);
3400       // Since 'ebuf' may contain a string encoded using
3401       // platform encoding scheme, we need to pass
3402       // Exceptions::unsafe_to_utf8 to the new_exception method
3403       // as the last argument. See bug 6367357.
3404       Handle h_exception =
3405         Exceptions::new_exception(thread,
3406                                   vmSymbols::java_lang_UnsatisfiedLinkError(),
3407                                   msg, Exceptions::unsafe_to_utf8);
3408 
3409       THROW_HANDLE_NULL(h_exception);
3410     } else {
3411       log_info(library)("Failed to load library %s", name);
3412       return load_result;
3413     }
3414   }
3415   log_info(library)("Loaded library %s, handle " INTPTR_FORMAT, name, p2i(load_result));
3416   return load_result;
3417 JVM_END
3418 
3419 
3420 JVM_LEAF(void, JVM_UnloadLibrary(void* handle))
3421   os::dll_unload(handle);
3422   log_info(library)("Unloaded library with handle " INTPTR_FORMAT, p2i(handle));
3423 JVM_END
3424 
3425 
3426 JVM_LEAF(void*, JVM_FindLibraryEntry(void* handle, const char* name))
3427   void* find_result = os::dll_lookup(handle, name);
3428   log_info(library)("%s %s in library with handle " INTPTR_FORMAT,
3429                     find_result != nullptr ? "Found" : "Failed to find",
3430                     name, p2i(handle));
3431   return find_result;
3432 JVM_END
3433 
3434 
3435 // JNI version ///////////////////////////////////////////////////////////////////////////////
3436 
3437 JVM_LEAF(jboolean, JVM_IsSupportedJNIVersion(jint version))
3438   return Threads::is_supported_jni_version_including_1_1(version);
3439 JVM_END
3440 
3441 
3442 JVM_LEAF(jboolean, JVM_IsPreviewEnabled(void))
3443   return Arguments::enable_preview() ? JNI_TRUE : JNI_FALSE;
3444 JVM_END
3445 
3446 JVM_LEAF(jboolean, JVM_IsValhallaEnabled(void))
3447   return EnableValhalla ? JNI_TRUE : JNI_FALSE;
3448 JVM_END
3449 
3450 JVM_LEAF(jboolean, JVM_IsContinuationsSupported(void))
3451   return VMContinuations ? JNI_TRUE : JNI_FALSE;
3452 JVM_END
3453 
3454 JVM_LEAF(jboolean, JVM_IsForeignLinkerSupported(void))
3455   return ForeignGlobals::is_foreign_linker_supported() ? JNI_TRUE : JNI_FALSE;
3456 JVM_END
3457 
3458 JVM_LEAF(jboolean, JVM_IsStaticallyLinked(void))
3459   return is_vm_statically_linked() ? JNI_TRUE : JNI_FALSE;
3460 JVM_END
3461 
3462 // String support ///////////////////////////////////////////////////////////////////////////
3463 
3464 JVM_ENTRY(jstring, JVM_InternString(JNIEnv *env, jstring str))
3465   JvmtiVMObjectAllocEventCollector oam;
3466   if (str == nullptr) return nullptr;
3467   oop string = JNIHandles::resolve_non_null(str);
3468   oop result = StringTable::intern(string, CHECK_NULL);
3469   return (jstring) JNIHandles::make_local(THREAD, result);
3470 JVM_END
3471 
3472 
3473 // VM Raw monitor support //////////////////////////////////////////////////////////////////////
3474 
3475 // VM Raw monitors (not to be confused with JvmtiRawMonitors) are a simple mutual exclusion
3476 // lock (not actually monitors: no wait/notify) that is exported by the VM for use by JDK
3477 // library code. They may be used by JavaThreads and non-JavaThreads and do not participate
3478 // in the safepoint protocol, thread suspension, thread interruption, or most things of that
3479 // nature, except JavaThreads will be blocked by VM_Exit::block_if_vm_exited if the VM has
3480 // shutdown. JavaThreads will be "in native" when using this API from JDK code.
3481 
3482 
3483 JNIEXPORT void* JNICALL JVM_RawMonitorCreate(void) {
3484   VM_Exit::block_if_vm_exited();
3485   return new PlatformMutex();
3486 }
3487 
3488 
3489 JNIEXPORT void JNICALL  JVM_RawMonitorDestroy(void *mon) {
3490   VM_Exit::block_if_vm_exited();
3491   delete ((PlatformMutex*) mon);
3492 }
3493 
3494 
3495 JNIEXPORT jint JNICALL JVM_RawMonitorEnter(void *mon) {
3496   VM_Exit::block_if_vm_exited();
3497   ((PlatformMutex*) mon)->lock();
3498   return 0;
3499 }
3500 
3501 
3502 JNIEXPORT void JNICALL JVM_RawMonitorExit(void *mon) {
3503   VM_Exit::block_if_vm_exited();
3504   ((PlatformMutex*) mon)->unlock();
3505 }
3506 
3507 
3508 // Shared JNI/JVM entry points //////////////////////////////////////////////////////////////
3509 
3510 jclass find_class_from_class_loader(JNIEnv* env, Symbol* name, jboolean init,
3511                                     Handle loader, jboolean throwError, TRAPS) {
3512   Klass* klass = SystemDictionary::resolve_or_fail(name, loader, throwError != 0, CHECK_NULL);
3513 
3514   // Check if we should initialize the class
3515   if (init && klass->is_instance_klass()) {
3516     klass->initialize(CHECK_NULL);
3517   }
3518   return (jclass) JNIHandles::make_local(THREAD, klass->java_mirror());
3519 }
3520 
3521 
3522 // Method ///////////////////////////////////////////////////////////////////////////////////////////
3523 
3524 JVM_ENTRY(jobject, JVM_InvokeMethod(JNIEnv *env, jobject method, jobject obj, jobjectArray args0))
3525   Handle method_handle;
3526   if (thread->stack_overflow_state()->stack_available((address) &method_handle) >= JVMInvokeMethodSlack) {
3527     method_handle = Handle(THREAD, JNIHandles::resolve(method));
3528     Handle receiver(THREAD, JNIHandles::resolve(obj));
3529     objArrayHandle args = oopFactory::ensure_objArray(JNIHandles::resolve(args0), CHECK_NULL);
3530     oop result = Reflection::invoke_method(method_handle(), receiver, args, CHECK_NULL);
3531     jobject res = JNIHandles::make_local(THREAD, result);
3532     if (JvmtiExport::should_post_vm_object_alloc()) {
3533       oop ret_type = java_lang_reflect_Method::return_type(method_handle());
3534       assert(ret_type != nullptr, "sanity check: ret_type oop must not be null!");
3535       if (java_lang_Class::is_primitive(ret_type)) {
3536         // Only for primitive type vm allocates memory for java object.
3537         // See box() method.
3538         JvmtiExport::post_vm_object_alloc(thread, result);
3539       }
3540     }
3541     return res;
3542   } else {
3543     THROW_NULL(vmSymbols::java_lang_StackOverflowError());
3544   }
3545 JVM_END
3546 
3547 
3548 JVM_ENTRY(jobject, JVM_NewInstanceFromConstructor(JNIEnv *env, jobject c, jobjectArray args0))
3549   objArrayHandle args = oopFactory::ensure_objArray(JNIHandles::resolve(args0), CHECK_NULL);
3550   oop constructor_mirror = JNIHandles::resolve(c);
3551   oop result = Reflection::invoke_constructor(constructor_mirror, args, CHECK_NULL);
3552   jobject res = JNIHandles::make_local(THREAD, result);
3553   if (JvmtiExport::should_post_vm_object_alloc()) {
3554     JvmtiExport::post_vm_object_alloc(thread, result);
3555   }
3556   return res;
3557 JVM_END
3558 
3559 JVM_ENTRY(void, JVM_InitializeFromArchive(JNIEnv* env, jclass cls))
3560   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve(cls));
3561   HeapShared::initialize_from_archived_subgraph(THREAD, k);
3562 JVM_END
3563 
3564 JVM_ENTRY(void, JVM_RegisterLambdaProxyClassForArchiving(JNIEnv* env,
3565                                               jclass caller,
3566                                               jstring interfaceMethodName,
3567                                               jobject factoryType,
3568                                               jobject interfaceMethodType,
3569                                               jobject implementationMember,
3570                                               jobject dynamicMethodType,
3571                                               jclass lambdaProxyClass))
3572 #if INCLUDE_CDS
3573   if (!CDSConfig::is_dumping_archive() || !CDSConfig::is_dumping_lambdas_in_legacy_mode()) {
3574     return;
3575   }
3576 
3577   Klass* caller_k = java_lang_Class::as_Klass(JNIHandles::resolve(caller));
3578   InstanceKlass* caller_ik = InstanceKlass::cast(caller_k);
3579   if (caller_ik->is_hidden()) {
3580     // Hidden classes not of type lambda proxy classes are currently not being archived.
3581     // If the caller_ik is of one of the above types, the corresponding lambda proxy class won't be
3582     // registered for archiving.
3583     return;
3584   }
3585   Klass* lambda_k = java_lang_Class::as_Klass(JNIHandles::resolve(lambdaProxyClass));
3586   InstanceKlass* lambda_ik = InstanceKlass::cast(lambda_k);
3587   assert(lambda_ik->is_hidden(), "must be a hidden class");
3588   assert(!lambda_ik->is_non_strong_hidden(), "expected a strong hidden class");
3589 
3590   Symbol* interface_method_name = nullptr;
3591   if (interfaceMethodName != nullptr) {
3592     interface_method_name = java_lang_String::as_symbol(JNIHandles::resolve_non_null(interfaceMethodName));
3593   }
3594   Handle factory_type_oop(THREAD, JNIHandles::resolve_non_null(factoryType));
3595   Symbol* factory_type = java_lang_invoke_MethodType::as_signature(factory_type_oop(), true);
3596 
3597   Handle interface_method_type_oop(THREAD, JNIHandles::resolve_non_null(interfaceMethodType));
3598   Symbol* interface_method_type = java_lang_invoke_MethodType::as_signature(interface_method_type_oop(), true);
3599 
3600   Handle implementation_member_oop(THREAD, JNIHandles::resolve_non_null(implementationMember));
3601   assert(java_lang_invoke_MemberName::is_method(implementation_member_oop()), "must be");
3602   Method* m = java_lang_invoke_MemberName::vmtarget(implementation_member_oop());
3603 
3604   Handle dynamic_method_type_oop(THREAD, JNIHandles::resolve_non_null(dynamicMethodType));
3605   Symbol* dynamic_method_type = java_lang_invoke_MethodType::as_signature(dynamic_method_type_oop(), true);
3606 
3607   LambdaProxyClassDictionary::add_lambda_proxy_class(caller_ik, lambda_ik, interface_method_name, factory_type,
3608                                                      interface_method_type, m, dynamic_method_type, THREAD);
3609 #endif // INCLUDE_CDS
3610 JVM_END
3611 
3612 JVM_ENTRY(jclass, JVM_LookupLambdaProxyClassFromArchive(JNIEnv* env,
3613                                                         jclass caller,
3614                                                         jstring interfaceMethodName,
3615                                                         jobject factoryType,
3616                                                         jobject interfaceMethodType,
3617                                                         jobject implementationMember,
3618                                                         jobject dynamicMethodType))
3619 #if INCLUDE_CDS
3620 
3621   if (interfaceMethodName == nullptr || factoryType == nullptr || interfaceMethodType == nullptr ||
3622       implementationMember == nullptr || dynamicMethodType == nullptr) {
3623     THROW_(vmSymbols::java_lang_NullPointerException(), nullptr);
3624   }
3625 
3626   Klass* caller_k = java_lang_Class::as_Klass(JNIHandles::resolve(caller));
3627   InstanceKlass* caller_ik = InstanceKlass::cast(caller_k);
3628   if (!caller_ik->is_shared()) {
3629     // there won't be a shared lambda class if the caller_ik is not in the shared archive.
3630     return nullptr;
3631   }
3632 
3633   Symbol* interface_method_name = java_lang_String::as_symbol(JNIHandles::resolve_non_null(interfaceMethodName));
3634   Handle factory_type_oop(THREAD, JNIHandles::resolve_non_null(factoryType));
3635   Symbol* factory_type = java_lang_invoke_MethodType::as_signature(factory_type_oop(), true);
3636 
3637   Handle interface_method_type_oop(THREAD, JNIHandles::resolve_non_null(interfaceMethodType));
3638   Symbol* interface_method_type = java_lang_invoke_MethodType::as_signature(interface_method_type_oop(), true);
3639 
3640   Handle implementation_member_oop(THREAD, JNIHandles::resolve_non_null(implementationMember));
3641   assert(java_lang_invoke_MemberName::is_method(implementation_member_oop()), "must be");
3642   Method* m = java_lang_invoke_MemberName::vmtarget(implementation_member_oop());
3643 
3644   Handle dynamic_method_type_oop(THREAD, JNIHandles::resolve_non_null(dynamicMethodType));
3645   Symbol* dynamic_method_type = java_lang_invoke_MethodType::as_signature(dynamic_method_type_oop(), true);
3646 
3647   InstanceKlass* loaded_lambda =
3648     LambdaProxyClassDictionary::load_shared_lambda_proxy_class(caller_ik, interface_method_name, factory_type,
3649                                                                interface_method_type, m, dynamic_method_type,
3650                                                                CHECK_(nullptr));
3651   return loaded_lambda == nullptr ? nullptr : (jclass) JNIHandles::make_local(THREAD, loaded_lambda->java_mirror());
3652 #else
3653   return nullptr;
3654 #endif // INCLUDE_CDS
3655 JVM_END
3656 
3657 JVM_ENTRY_NO_ENV(jlong, JVM_GetRandomSeedForDumping())
3658   if (CDSConfig::is_dumping_static_archive()) {
3659     // We do this so that the default CDS archive can be deterministic.
3660     const char* release = VM_Version::vm_release();
3661     const char* dbg_level = VM_Version::jdk_debug_level();
3662     const char* version = VM_Version::internal_vm_info_string();
3663     jlong seed = (jlong)(java_lang_String::hash_code((const jbyte*)release, (int)strlen(release)) ^
3664                          java_lang_String::hash_code((const jbyte*)dbg_level, (int)strlen(dbg_level)) ^
3665                          java_lang_String::hash_code((const jbyte*)version, (int)strlen(version)));
3666     seed += (jlong)VM_Version::vm_major_version();
3667     seed += (jlong)VM_Version::vm_minor_version();
3668     seed += (jlong)VM_Version::vm_security_version();
3669     seed += (jlong)VM_Version::vm_patch_version();
3670     if (seed == 0) { // don't let this ever be zero.
3671       seed = 0x87654321;
3672     }
3673     log_debug(cds)("JVM_GetRandomSeedForDumping() = " JLONG_FORMAT, seed);
3674     return seed;
3675   } else {
3676     return 0;
3677   }
3678 JVM_END
3679 
3680 JVM_ENTRY_NO_ENV(jint, JVM_GetCDSConfigStatus())
3681   return CDSConfig::get_status();
3682 JVM_END
3683 
3684 JVM_ENTRY(void, JVM_LogLambdaFormInvoker(JNIEnv *env, jstring line))
3685 #if INCLUDE_CDS
3686   assert(CDSConfig::is_logging_lambda_form_invokers(), "sanity");
3687   if (line != nullptr) {
3688     ResourceMark rm(THREAD);
3689     Handle h_line (THREAD, JNIHandles::resolve_non_null(line));
3690     char* c_line = java_lang_String::as_utf8_string(h_line());
3691     if (CDSConfig::is_dumping_dynamic_archive()) {
3692       // Note: LambdaFormInvokers::append take same format which is not
3693       // same as below the print format. The line does not include LAMBDA_FORM_TAG.
3694       LambdaFormInvokers::append(os::strdup((const char*)c_line, mtInternal));
3695     }
3696     if (ClassListWriter::is_enabled()) {
3697       ClassListWriter w;
3698       w.stream()->print_cr("%s %s", ClassListParser::lambda_form_tag(), c_line);
3699     }
3700   }
3701 #endif // INCLUDE_CDS
3702 JVM_END
3703 
3704 JVM_ENTRY(void, JVM_DumpClassListToFile(JNIEnv *env, jstring listFileName))
3705 #if INCLUDE_CDS
3706   ResourceMark rm(THREAD);
3707   Handle file_handle(THREAD, JNIHandles::resolve_non_null(listFileName));
3708   char* file_name  = java_lang_String::as_utf8_string(file_handle());
3709   MetaspaceShared::dump_loaded_classes(file_name, THREAD);
3710 #endif // INCLUDE_CDS
3711 JVM_END
3712 
3713 JVM_ENTRY(void, JVM_DumpDynamicArchive(JNIEnv *env, jstring archiveName))
3714 #if INCLUDE_CDS
3715   ResourceMark rm(THREAD);
3716   Handle file_handle(THREAD, JNIHandles::resolve_non_null(archiveName));
3717   char* archive_name  = java_lang_String::as_utf8_string(file_handle());
3718   DynamicArchive::dump_for_jcmd(archive_name, CHECK);
3719 #endif // INCLUDE_CDS
3720 JVM_END
3721 
3722 JVM_ENTRY(jboolean, JVM_NeedsClassInitBarrierForCDS(JNIEnv* env, jclass cls))
3723 #if INCLUDE_CDS
3724   Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve(cls));
3725   if (!k->is_instance_klass()) {
3726     return false;
3727   } else {
3728     if (InstanceKlass::cast(k)->is_enum_subclass() ||
3729         AOTClassInitializer::can_archive_initialized_mirror(InstanceKlass::cast(k))) {
3730       // This class will be cached in AOT-initialized state. No need for init barriers.
3731       return false;
3732     } else {
3733       // If we cannot cache the class in AOT-initialized state, java.lang.invoke handles
3734       // must emit barriers to ensure class initialization during production run.
3735       ResourceMark rm(THREAD);
3736       log_debug(cds)("NeedsClassInitBarrierForCDS: %s", k->external_name());
3737       return true;
3738     }
3739   }
3740 #else
3741   return false;
3742 #endif // INCLUDE_CDS
3743 JVM_END
3744 
3745 // Returns an array of all live Thread objects (VM internal JavaThreads,
3746 // jvmti agent threads, and JNI attaching threads  are skipped)
3747 // See CR 6404306 regarding JNI attaching threads
3748 JVM_ENTRY(jobjectArray, JVM_GetAllThreads(JNIEnv *env, jclass dummy))
3749   ResourceMark rm(THREAD);
3750   ThreadsListEnumerator tle(THREAD, false, false);
3751   JvmtiVMObjectAllocEventCollector oam;
3752 
3753   int num_threads = tle.num_threads();
3754   objArrayOop r = oopFactory::new_objArray(vmClasses::Thread_klass(), num_threads, CHECK_NULL);
3755   objArrayHandle threads_ah(THREAD, r);
3756 
3757   for (int i = 0; i < num_threads; i++) {
3758     Handle h = tle.get_threadObj(i);
3759     threads_ah->obj_at_put(i, h());
3760   }
3761 
3762   return (jobjectArray) JNIHandles::make_local(THREAD, threads_ah());
3763 JVM_END
3764 
3765 
3766 // Support for java.lang.Thread.getStackTrace() and getAllStackTraces() methods
3767 // Return StackTraceElement[][], each element is the stack trace of a thread in
3768 // the corresponding entry in the given threads array
3769 JVM_ENTRY(jobjectArray, JVM_DumpThreads(JNIEnv *env, jclass threadClass, jobjectArray threads))
3770   JvmtiVMObjectAllocEventCollector oam;
3771 
3772   // Check if threads is null
3773   if (threads == nullptr) {
3774     THROW_NULL(vmSymbols::java_lang_NullPointerException());
3775   }
3776 
3777   objArrayOop a = objArrayOop(JNIHandles::resolve_non_null(threads));
3778   objArrayHandle ah(THREAD, a);
3779   int num_threads = ah->length();
3780   // check if threads is non-empty array
3781   if (num_threads == 0) {
3782     THROW_NULL(vmSymbols::java_lang_IllegalArgumentException());
3783   }
3784 
3785   // check if threads is not an array of objects of Thread class
3786   Klass* k = ObjArrayKlass::cast(ah->klass())->element_klass();
3787   if (k != vmClasses::Thread_klass()) {
3788     THROW_NULL(vmSymbols::java_lang_IllegalArgumentException());
3789   }
3790 
3791   ResourceMark rm(THREAD);
3792 
3793   GrowableArray<instanceHandle>* thread_handle_array = new GrowableArray<instanceHandle>(num_threads);
3794   for (int i = 0; i < num_threads; i++) {
3795     oop thread_obj = ah->obj_at(i);
3796     instanceHandle h(THREAD, (instanceOop) thread_obj);
3797     thread_handle_array->append(h);
3798   }
3799 
3800   // The JavaThread references in thread_handle_array are validated
3801   // in VM_ThreadDump::doit().
3802   Handle stacktraces = ThreadService::dump_stack_traces(thread_handle_array, num_threads, CHECK_NULL);
3803   return (jobjectArray)JNIHandles::make_local(THREAD, stacktraces());
3804 
3805 JVM_END
3806 
3807 // JVM monitoring and management support
3808 JVM_LEAF(void*, JVM_GetManagement(jint version))
3809   return Management::get_jmm_interface(version);
3810 JVM_END
3811 
3812 // com.sun.tools.attach.VirtualMachine agent properties support
3813 //
3814 // Initialize the agent properties with the properties maintained in the VM
3815 JVM_ENTRY(jobject, JVM_InitAgentProperties(JNIEnv *env, jobject properties))
3816   ResourceMark rm;
3817 
3818   Handle props(THREAD, JNIHandles::resolve_non_null(properties));
3819 
3820   PUTPROP(props, "sun.java.command", Arguments::java_command());
3821   PUTPROP(props, "sun.jvm.flags", Arguments::jvm_flags());
3822   PUTPROP(props, "sun.jvm.args", Arguments::jvm_args());
3823   return properties;
3824 JVM_END
3825 
3826 JVM_ENTRY(jobjectArray, JVM_GetEnclosingMethodInfo(JNIEnv *env, jclass ofClass))
3827 {
3828   JvmtiVMObjectAllocEventCollector oam;
3829 
3830   if (ofClass == nullptr) {
3831     return nullptr;
3832   }
3833   Handle mirror(THREAD, JNIHandles::resolve_non_null(ofClass));
3834   // Special handling for primitive objects
3835   if (java_lang_Class::is_primitive(mirror())) {
3836     return nullptr;
3837   }
3838   Klass* k = java_lang_Class::as_Klass(mirror());
3839   if (!k->is_instance_klass()) {
3840     return nullptr;
3841   }
3842   InstanceKlass* ik = InstanceKlass::cast(k);
3843   int encl_method_class_idx = ik->enclosing_method_class_index();
3844   if (encl_method_class_idx == 0) {
3845     return nullptr;
3846   }
3847   objArrayOop dest_o = oopFactory::new_objArray(vmClasses::Object_klass(), 3, CHECK_NULL);
3848   objArrayHandle dest(THREAD, dest_o);
3849   Klass* enc_k = ik->constants()->klass_at(encl_method_class_idx, CHECK_NULL);
3850   dest->obj_at_put(0, enc_k->java_mirror());
3851   int encl_method_method_idx = ik->enclosing_method_method_index();
3852   if (encl_method_method_idx != 0) {
3853     Symbol* sym = ik->constants()->symbol_at(
3854                         extract_low_short_from_int(
3855                           ik->constants()->name_and_type_at(encl_method_method_idx)));
3856     Handle str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
3857     dest->obj_at_put(1, str());
3858     sym = ik->constants()->symbol_at(
3859               extract_high_short_from_int(
3860                 ik->constants()->name_and_type_at(encl_method_method_idx)));
3861     str = java_lang_String::create_from_symbol(sym, CHECK_NULL);
3862     dest->obj_at_put(2, str());
3863   }
3864   return (jobjectArray) JNIHandles::make_local(THREAD, dest());
3865 }
3866 JVM_END
3867 
3868 // Returns an array of java.lang.String objects containing the input arguments to the VM.
3869 JVM_ENTRY(jobjectArray, JVM_GetVmArguments(JNIEnv *env))
3870   ResourceMark rm(THREAD);
3871 
3872   if (Arguments::num_jvm_args() == 0 && Arguments::num_jvm_flags() == 0) {
3873     return nullptr;
3874   }
3875 
3876   char** vm_flags = Arguments::jvm_flags_array();
3877   char** vm_args = Arguments::jvm_args_array();
3878   int num_flags = Arguments::num_jvm_flags();
3879   int num_args = Arguments::num_jvm_args();
3880 
3881   InstanceKlass* ik = vmClasses::String_klass();
3882   objArrayOop r = oopFactory::new_objArray(ik, num_args + num_flags, CHECK_NULL);
3883   objArrayHandle result_h(THREAD, r);
3884 
3885   int index = 0;
3886   for (int j = 0; j < num_flags; j++, index++) {
3887     Handle h = java_lang_String::create_from_platform_dependent_str(vm_flags[j], CHECK_NULL);
3888     result_h->obj_at_put(index, h());
3889   }
3890   for (int i = 0; i < num_args; i++, index++) {
3891     Handle h = java_lang_String::create_from_platform_dependent_str(vm_args[i], CHECK_NULL);
3892     result_h->obj_at_put(index, h());
3893   }
3894   return (jobjectArray) JNIHandles::make_local(THREAD, result_h());
3895 JVM_END
3896 
3897 JVM_LEAF(jint, JVM_FindSignal(const char *name))
3898   return os::get_signal_number(name);
3899 JVM_END
3900 
3901 JVM_ENTRY(void, JVM_VirtualThreadStart(JNIEnv* env, jobject vthread))
3902 #if INCLUDE_JVMTI
3903   if (!DoJVMTIVirtualThreadTransitions) {
3904     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
3905     return;
3906   }
3907   if (JvmtiVTMSTransitionDisabler::VTMS_notify_jvmti_events()) {
3908     JvmtiVTMSTransitionDisabler::VTMS_vthread_start(vthread);
3909   } else {
3910     // set VTMS transition bit value in JavaThread and java.lang.VirtualThread object
3911     JvmtiVTMSTransitionDisabler::set_is_in_VTMS_transition(thread, vthread, false);
3912   }
3913 #endif
3914 JVM_END
3915 
3916 JVM_ENTRY(void, JVM_VirtualThreadEnd(JNIEnv* env, jobject vthread))
3917 #if INCLUDE_JVMTI
3918   if (!DoJVMTIVirtualThreadTransitions) {
3919     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
3920     return;
3921   }
3922   if (JvmtiVTMSTransitionDisabler::VTMS_notify_jvmti_events()) {
3923     JvmtiVTMSTransitionDisabler::VTMS_vthread_end(vthread);
3924   } else {
3925     // set VTMS transition bit value in JavaThread and java.lang.VirtualThread object
3926     JvmtiVTMSTransitionDisabler::set_is_in_VTMS_transition(thread, vthread, true);
3927   }
3928 #endif
3929 JVM_END
3930 
3931 // If notifications are disabled then just update the VTMS transition bit and return.
3932 // Otherwise, the bit is updated in the given jvmtiVTMSTransitionDisabler function call.
3933 JVM_ENTRY(void, JVM_VirtualThreadMount(JNIEnv* env, jobject vthread, jboolean hide))
3934 #if INCLUDE_JVMTI
3935   if (!DoJVMTIVirtualThreadTransitions) {
3936     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
3937     return;
3938   }
3939   if (JvmtiVTMSTransitionDisabler::VTMS_notify_jvmti_events()) {
3940     JvmtiVTMSTransitionDisabler::VTMS_vthread_mount(vthread, hide);
3941   } else {
3942     // set VTMS transition bit value in JavaThread and java.lang.VirtualThread object
3943     JvmtiVTMSTransitionDisabler::set_is_in_VTMS_transition(thread, vthread, hide);
3944   }
3945 #endif
3946 JVM_END
3947 
3948 // If notifications are disabled then just update the VTMS transition bit and return.
3949 // Otherwise, the bit is updated in the given jvmtiVTMSTransitionDisabler function call below.
3950 JVM_ENTRY(void, JVM_VirtualThreadUnmount(JNIEnv* env, jobject vthread, jboolean hide))
3951 #if INCLUDE_JVMTI
3952   if (!DoJVMTIVirtualThreadTransitions) {
3953     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
3954     return;
3955   }
3956   if (JvmtiVTMSTransitionDisabler::VTMS_notify_jvmti_events()) {
3957     JvmtiVTMSTransitionDisabler::VTMS_vthread_unmount(vthread, hide);
3958   } else {
3959     // set VTMS transition bit value in JavaThread and java.lang.VirtualThread object
3960     JvmtiVTMSTransitionDisabler::set_is_in_VTMS_transition(thread, vthread, hide);
3961   }
3962 #endif
3963 JVM_END
3964 
3965 // Notification from VirtualThread about disabling JVMTI Suspend in a sync critical section.
3966 // Needed to avoid deadlocks with JVMTI suspend mechanism.
3967 JVM_ENTRY(void, JVM_VirtualThreadDisableSuspend(JNIEnv* env, jclass clazz, jboolean enter))
3968 #if INCLUDE_JVMTI
3969   if (!DoJVMTIVirtualThreadTransitions) {
3970     assert(!JvmtiExport::can_support_virtual_threads(), "sanity check");
3971     return;
3972   }
3973   assert(thread->is_disable_suspend() != (bool)enter,
3974          "nested or unbalanced monitor enter/exit is not allowed");
3975   thread->toggle_is_disable_suspend();
3976 #endif
3977 JVM_END
3978 
3979 JVM_ENTRY(void, JVM_VirtualThreadPinnedEvent(JNIEnv* env, jclass ignored, jstring op))
3980 #if INCLUDE_JFR
3981   freeze_result result = THREAD->last_freeze_fail_result();
3982   assert(result != freeze_ok, "sanity check");
3983   EventVirtualThreadPinned event(UNTIMED);
3984   event.set_starttime(THREAD->last_freeze_fail_time());
3985   if (event.should_commit()) {
3986     ResourceMark rm(THREAD);
3987     const char *str = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(op));
3988     THREAD->post_vthread_pinned_event(&event, str, result);
3989   }
3990 #endif
3991 JVM_END
3992 
3993 JVM_ENTRY(jobject, JVM_TakeVirtualThreadListToUnblock(JNIEnv* env, jclass ignored))
3994   ParkEvent* parkEvent = ObjectMonitor::vthread_unparker_ParkEvent();
3995   assert(parkEvent != nullptr, "not initialized");
3996 
3997   OopHandle& list_head = ObjectMonitor::vthread_list_head();
3998   oop vthread_head = nullptr;
3999   while (true) {
4000     if (list_head.peek() != nullptr) {
4001       for (;;) {
4002         oop head = list_head.resolve();
4003         if (list_head.cmpxchg(head, nullptr) == head) {
4004           return JNIHandles::make_local(THREAD, head);
4005         }
4006       }
4007     }
4008     ThreadBlockInVM tbivm(THREAD);
4009     parkEvent->park();
4010   }
4011 JVM_END
4012 /*
4013  * Return the current class's class file version.  The low order 16 bits of the
4014  * returned jint contain the class's major version.  The high order 16 bits
4015  * contain the class's minor version.
4016  */
4017 JVM_ENTRY(jint, JVM_GetClassFileVersion(JNIEnv* env, jclass current))
4018   oop mirror = JNIHandles::resolve_non_null(current);
4019   if (java_lang_Class::is_primitive(mirror)) {
4020     // return latest major version and minor version of 0.
4021     return JVM_CLASSFILE_MAJOR_VERSION;
4022   }
4023   assert(!java_lang_Class::as_Klass(mirror)->is_array_klass(), "unexpected array class");
4024 
4025   Klass* c = java_lang_Class::as_Klass(mirror);
4026   assert(c->is_instance_klass(), "must be");
4027   InstanceKlass* ik = InstanceKlass::cast(c);
4028   return (ik->minor_version() << 16) | ik->major_version();
4029 JVM_END
4030 
4031 /*
4032  * Ensure that code doing a stackwalk and using javaVFrame::locals() to
4033  * get the value will see a materialized value and not a scalar-replaced
4034  * null value.
4035  */
4036 JVM_ENTRY(void, JVM_EnsureMaterializedForStackWalk_func(JNIEnv* env, jobject vthread, jobject value))
4037   JVM_EnsureMaterializedForStackWalk(env, value);
4038 JVM_END
4039 
4040 /*
4041  * Return JNI_TRUE if warnings are printed when agents are dynamically loaded.
4042  */
4043 JVM_LEAF(jboolean, JVM_PrintWarningAtDynamicAgentLoad(void))
4044   return (EnableDynamicAgentLoading && !FLAG_IS_CMDLINE(EnableDynamicAgentLoading)) ? JNI_TRUE : JNI_FALSE;
4045 JVM_END