1 /*
   2  * Copyright (c) 1997, 2026, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "cds/aotLogging.hpp"
  26 #include "cds/cds_globals.hpp"
  27 #include "cds/cdsConfig.hpp"
  28 #include "classfile/classLoader.hpp"
  29 #include "classfile/javaAssertions.hpp"
  30 #include "classfile/moduleEntry.hpp"
  31 #include "classfile/stringTable.hpp"
  32 #include "classfile/symbolTable.hpp"
  33 #include "compiler/compilerDefinitions.hpp"
  34 #include "cppstdlib/limits.hpp"
  35 #include "gc/shared/gc_globals.hpp"
  36 #include "gc/shared/gcArguments.hpp"
  37 #include "gc/shared/gcConfig.hpp"
  38 #include "gc/shared/genArguments.hpp"
  39 #include "gc/shared/stringdedup/stringDedup.hpp"
  40 #include "gc/shared/tlab_globals.hpp"
  41 #include "jvm.h"
  42 #include "logging/log.hpp"
  43 #include "logging/logConfiguration.hpp"
  44 #include "logging/logStream.hpp"
  45 #include "logging/logTag.hpp"
  46 #include "memory/allocation.inline.hpp"
  47 #include "nmt/nmtCommon.hpp"
  48 #include "oops/compressedKlass.hpp"
  49 #include "oops/instanceKlass.hpp"
  50 #include "oops/objLayout.hpp"
  51 #include "oops/oop.inline.hpp"
  52 #include "prims/jvmtiAgentList.hpp"
  53 #include "prims/jvmtiExport.hpp"
  54 #include "runtime/arguments.hpp"
  55 #include "runtime/flags/jvmFlag.hpp"
  56 #include "runtime/flags/jvmFlagAccess.hpp"
  57 #include "runtime/flags/jvmFlagLimit.hpp"
  58 #include "runtime/globals_extension.hpp"
  59 #include "runtime/java.hpp"
  60 #include "runtime/os.hpp"
  61 #include "runtime/safepoint.hpp"
  62 #include "runtime/safepointMechanism.hpp"
  63 #include "runtime/synchronizer.hpp"
  64 #include "runtime/vm_version.hpp"
  65 #include "services/management.hpp"
  66 #include "utilities/align.hpp"
  67 #include "utilities/debug.hpp"
  68 #include "utilities/defaultStream.hpp"
  69 #include "utilities/macros.hpp"
  70 #include "utilities/parseInteger.hpp"
  71 #include "utilities/powerOfTwo.hpp"
  72 #include "utilities/stringUtils.hpp"
  73 #include "utilities/systemMemoryBarrier.hpp"
  74 #if INCLUDE_JFR
  75 #include "jfr/jfr.hpp"
  76 #endif
  77 
  78 #include <string.h>
  79 
  80 static const char _default_java_launcher[] = "generic";
  81 
  82 #define DEFAULT_JAVA_LAUNCHER _default_java_launcher
  83 
  84 char*  Arguments::_jvm_flags_file               = nullptr;
  85 char** Arguments::_jvm_flags_array              = nullptr;
  86 int    Arguments::_num_jvm_flags                = 0;
  87 char** Arguments::_jvm_args_array               = nullptr;
  88 int    Arguments::_num_jvm_args                 = 0;
  89 unsigned int Arguments::_addmods_count          = 0;
  90 #if INCLUDE_JVMCI
  91 bool   Arguments::_jvmci_module_added           = false;
  92 #endif
  93 char*  Arguments::_java_command                 = nullptr;
  94 SystemProperty* Arguments::_system_properties   = nullptr;
  95 size_t Arguments::_conservative_max_heap_alignment = 0;
  96 Arguments::Mode Arguments::_mode                = _mixed;
  97 const char*  Arguments::_java_vendor_url_bug    = nullptr;
  98 const char*  Arguments::_sun_java_launcher      = DEFAULT_JAVA_LAUNCHER;
  99 bool   Arguments::_executing_unit_tests         = false;
 100 
 101 // These parameters are reset in method parse_vm_init_args()
 102 bool   Arguments::_AlwaysCompileLoopMethods     = AlwaysCompileLoopMethods;
 103 bool   Arguments::_UseOnStackReplacement        = UseOnStackReplacement;
 104 bool   Arguments::_BackgroundCompilation        = BackgroundCompilation;
 105 bool   Arguments::_ClipInlining                 = ClipInlining;
 106 size_t Arguments::_default_SharedBaseAddress    = SharedBaseAddress;
 107 
 108 bool   Arguments::_enable_preview               = false;
 109 bool   Arguments::_has_jdwp_agent               = false;
 110 
 111 LegacyGCLogging Arguments::_legacyGCLogging     = { nullptr, 0 };
 112 
 113 // These are not set by the JDK's built-in launchers, but they can be set by
 114 // programs that embed the JVM using JNI_CreateJavaVM. See comments around
 115 // JavaVMOption in jni.h.
 116 abort_hook_t     Arguments::_abort_hook         = nullptr;
 117 exit_hook_t      Arguments::_exit_hook          = nullptr;
 118 vfprintf_hook_t  Arguments::_vfprintf_hook      = nullptr;
 119 
 120 
 121 SystemProperty *Arguments::_sun_boot_library_path = nullptr;
 122 SystemProperty *Arguments::_java_library_path = nullptr;
 123 SystemProperty *Arguments::_java_home = nullptr;
 124 SystemProperty *Arguments::_java_class_path = nullptr;
 125 SystemProperty *Arguments::_jdk_boot_class_path_append = nullptr;
 126 SystemProperty *Arguments::_vm_info = nullptr;
 127 
 128 GrowableArray<ModulePatchPath*> *Arguments::_patch_mod_prefix = nullptr;
 129 PathString *Arguments::_boot_class_path = nullptr;
 130 bool Arguments::_has_jimage = false;
 131 
 132 char* Arguments::_ext_dirs = nullptr;
 133 
 134 // True if -Xshare:auto option was specified.
 135 static bool xshare_auto_cmd_line = false;
 136 
 137 // True if -Xint/-Xmixed/-Xcomp were specified
 138 static bool mode_flag_cmd_line = false;
 139 
 140 struct VMInitArgsGroup {
 141   const JavaVMInitArgs* _args;
 142   JVMFlagOrigin _origin;
 143 };
 144 
 145 bool PathString::set_value(const char *value, AllocFailType alloc_failmode) {
 146   char* new_value = AllocateHeap(strlen(value)+1, mtArguments, alloc_failmode);
 147   if (new_value == nullptr) {
 148     assert(alloc_failmode == AllocFailStrategy::RETURN_NULL, "must be");
 149     return false;
 150   }
 151   if (_value != nullptr) {
 152     FreeHeap(_value);
 153   }
 154   _value = new_value;
 155   strcpy(_value, value);
 156   return true;
 157 }
 158 
 159 void PathString::append_value(const char *value) {
 160   char *sp;
 161   size_t len = 0;
 162   if (value != nullptr) {
 163     len = strlen(value);
 164     if (_value != nullptr) {
 165       len += strlen(_value);
 166     }
 167     sp = AllocateHeap(len+2, mtArguments);
 168     assert(sp != nullptr, "Unable to allocate space for new append path value");
 169     if (sp != nullptr) {
 170       if (_value != nullptr) {
 171         strcpy(sp, _value);
 172         strcat(sp, os::path_separator());
 173         strcat(sp, value);
 174         FreeHeap(_value);
 175       } else {
 176         strcpy(sp, value);
 177       }
 178       _value = sp;
 179     }
 180   }
 181 }
 182 
 183 PathString::PathString(const char* value) {
 184   if (value == nullptr) {
 185     _value = nullptr;
 186   } else {
 187     _value = AllocateHeap(strlen(value)+1, mtArguments);
 188     strcpy(_value, value);
 189   }
 190 }
 191 
 192 PathString::~PathString() {
 193   if (_value != nullptr) {
 194     FreeHeap(_value);
 195     _value = nullptr;
 196   }
 197 }
 198 
 199 ModulePatchPath::ModulePatchPath(const char* module_name, const char* path) {
 200   assert(module_name != nullptr && path != nullptr, "Invalid module name or path value");
 201   size_t len = strlen(module_name) + 1;
 202   _module_name = AllocateHeap(len, mtInternal);
 203   strncpy(_module_name, module_name, len); // copy the trailing null
 204   _path =  new PathString(path);
 205 }
 206 
 207 ModulePatchPath::~ModulePatchPath() {
 208   if (_module_name != nullptr) {
 209     FreeHeap(_module_name);
 210     _module_name = nullptr;
 211   }
 212   if (_path != nullptr) {
 213     delete _path;
 214     _path = nullptr;
 215   }
 216 }
 217 
 218 SystemProperty::SystemProperty(const char* key, const char* value, bool writeable, bool internal) : PathString(value) {
 219   if (key == nullptr) {
 220     _key = nullptr;
 221   } else {
 222     _key = AllocateHeap(strlen(key)+1, mtArguments);
 223     strcpy(_key, key);
 224   }
 225   _next = nullptr;
 226   _internal = internal;
 227   _writeable = writeable;
 228 }
 229 
 230 // Check if head of 'option' matches 'name', and sets 'tail' to the remaining
 231 // part of the option string.
 232 static bool match_option(const JavaVMOption *option, const char* name,
 233                          const char** tail) {
 234   size_t len = strlen(name);
 235   if (strncmp(option->optionString, name, len) == 0) {
 236     *tail = option->optionString + len;
 237     return true;
 238   } else {
 239     return false;
 240   }
 241 }
 242 
 243 // Check if 'option' matches 'name'. No "tail" is allowed.
 244 static bool match_option(const JavaVMOption *option, const char* name) {
 245   const char* tail = nullptr;
 246   bool result = match_option(option, name, &tail);
 247   if (tail != nullptr && *tail == '\0') {
 248     return result;
 249   } else {
 250     return false;
 251   }
 252 }
 253 
 254 // Return true if any of the strings in null-terminated array 'names' matches.
 255 // If tail_allowed is true, then the tail must begin with a colon; otherwise,
 256 // the option must match exactly.
 257 static bool match_option(const JavaVMOption* option, const char** names, const char** tail,
 258   bool tail_allowed) {
 259   for (/* empty */; *names != nullptr; ++names) {
 260   if (match_option(option, *names, tail)) {
 261       if (**tail == '\0' || (tail_allowed && **tail == ':')) {
 262         return true;
 263       }
 264     }
 265   }
 266   return false;
 267 }
 268 
 269 #if INCLUDE_JFR
 270 static bool _has_jfr_option = false;  // is using JFR
 271 
 272 // return true on failure
 273 static bool match_jfr_option(const JavaVMOption** option) {
 274   assert((*option)->optionString != nullptr, "invariant");
 275   char* tail = nullptr;
 276   if (match_option(*option, "-XX:StartFlightRecording", (const char**)&tail)) {
 277     _has_jfr_option = true;
 278     return Jfr::on_start_flight_recording_option(option, tail);
 279   } else if (match_option(*option, "-XX:FlightRecorderOptions", (const char**)&tail)) {
 280     _has_jfr_option = true;
 281     return Jfr::on_flight_recorder_option(option, tail);
 282   }
 283   return false;
 284 }
 285 
 286 bool Arguments::has_jfr_option() {
 287   return _has_jfr_option;
 288 }
 289 #endif
 290 
 291 static void logOption(const char* opt) {
 292   if (PrintVMOptions) {
 293     jio_fprintf(defaultStream::output_stream(), "VM option '%s'\n", opt);
 294   }
 295 }
 296 
 297 bool needs_module_property_warning = false;
 298 
 299 #define MODULE_PROPERTY_PREFIX "jdk.module."
 300 #define MODULE_PROPERTY_PREFIX_LEN 11
 301 #define ADDEXPORTS "addexports"
 302 #define ADDEXPORTS_LEN 10
 303 #define ADDREADS "addreads"
 304 #define ADDREADS_LEN 8
 305 #define ADDOPENS "addopens"
 306 #define ADDOPENS_LEN 8
 307 #define PATCH "patch"
 308 #define PATCH_LEN 5
 309 #define ADDMODS "addmods"
 310 #define ADDMODS_LEN 7
 311 #define LIMITMODS "limitmods"
 312 #define LIMITMODS_LEN 9
 313 #define PATH "path"
 314 #define PATH_LEN 4
 315 #define UPGRADE_PATH "upgrade.path"
 316 #define UPGRADE_PATH_LEN 12
 317 #define ENABLE_NATIVE_ACCESS "enable.native.access"
 318 #define ENABLE_NATIVE_ACCESS_LEN 20
 319 #define ILLEGAL_NATIVE_ACCESS "illegal.native.access"
 320 #define ILLEGAL_NATIVE_ACCESS_LEN 21
 321 #define ENABLE_FINAL_FIELD_MUTATION "enable.final.field.mutation"
 322 #define ENABLE_FINAL_FIELD_MUTATION_LEN 27
 323 #define ILLEGAL_FINAL_FIELD_MUTATION "illegal.final.field.mutation"
 324 #define ILLEGAL_FINAL_FIELD_MUTATION_LEN 28
 325 
 326 // Return TRUE if option matches 'property', or 'property=', or 'property.'.
 327 static bool matches_property_suffix(const char* option, const char* property, size_t len) {
 328   return ((strncmp(option, property, len) == 0) &&
 329           (option[len] == '=' || option[len] == '.' || option[len] == '\0'));
 330 }
 331 
 332 // Return true if property starts with "jdk.module." and its ensuing chars match
 333 // any of the reserved module properties.
 334 // property should be passed without the leading "-D".
 335 bool Arguments::is_internal_module_property(const char* property) {
 336   return internal_module_property_helper(property, false);
 337 }
 338 
 339 // Returns true if property is one of those recognized by is_internal_module_property() but
 340 // is not supported by CDS archived full module graph.
 341 bool Arguments::is_incompatible_cds_internal_module_property(const char* property) {
 342   return internal_module_property_helper(property, true);
 343 }
 344 
 345 bool Arguments::internal_module_property_helper(const char* property, bool check_for_cds) {
 346   if (strncmp(property, MODULE_PROPERTY_PREFIX, MODULE_PROPERTY_PREFIX_LEN) == 0) {
 347     const char* property_suffix = property + MODULE_PROPERTY_PREFIX_LEN;
 348     if (matches_property_suffix(property_suffix, PATCH, PATCH_LEN) ||
 349         matches_property_suffix(property_suffix, LIMITMODS, LIMITMODS_LEN) ||
 350         matches_property_suffix(property_suffix, UPGRADE_PATH, UPGRADE_PATH_LEN) ||
 351         matches_property_suffix(property_suffix, ILLEGAL_NATIVE_ACCESS, ILLEGAL_NATIVE_ACCESS_LEN) ||
 352         matches_property_suffix(property_suffix, ENABLE_FINAL_FIELD_MUTATION, ENABLE_FINAL_FIELD_MUTATION_LEN) ||
 353         matches_property_suffix(property_suffix, ILLEGAL_FINAL_FIELD_MUTATION, ILLEGAL_FINAL_FIELD_MUTATION_LEN)) {
 354       return true;
 355     }
 356 
 357     if (!check_for_cds) {
 358       // CDS notes: these properties are supported by CDS archived full module graph.
 359       if (matches_property_suffix(property_suffix, ADDEXPORTS, ADDEXPORTS_LEN) ||
 360           matches_property_suffix(property_suffix, ADDOPENS, ADDOPENS_LEN) ||
 361           matches_property_suffix(property_suffix, ADDREADS, ADDREADS_LEN) ||
 362           matches_property_suffix(property_suffix, PATH, PATH_LEN) ||
 363           matches_property_suffix(property_suffix, ADDMODS, ADDMODS_LEN) ||
 364           matches_property_suffix(property_suffix, ENABLE_NATIVE_ACCESS, ENABLE_NATIVE_ACCESS_LEN)) {
 365         return true;
 366       }
 367     }
 368   }
 369   return false;
 370 }
 371 
 372 // Process java launcher properties.
 373 void Arguments::process_sun_java_launcher_properties(JavaVMInitArgs* args) {
 374   // See if sun.java.launcher is defined.
 375   // Must do this before setting up other system properties,
 376   // as some of them may depend on launcher type.
 377   for (int index = 0; index < args->nOptions; index++) {
 378     const JavaVMOption* option = args->options + index;
 379     const char* tail;
 380 
 381     if (match_option(option, "-Dsun.java.launcher=", &tail)) {
 382       process_java_launcher_argument(tail, option->extraInfo);
 383       continue;
 384     }
 385     if (match_option(option, "-XX:+ExecutingUnitTests")) {
 386       _executing_unit_tests = true;
 387       continue;
 388     }
 389   }
 390 }
 391 
 392 // Initialize system properties key and value.
 393 void Arguments::init_system_properties() {
 394 
 395   // Set up _boot_class_path which is not a property but
 396   // relies heavily on argument processing and the jdk.boot.class.path.append
 397   // property. It is used to store the underlying boot class path.
 398   _boot_class_path = new PathString(nullptr);
 399 
 400   PropertyList_add(&_system_properties, new SystemProperty("java.vm.specification.name",
 401                                                            "Java Virtual Machine Specification",  false));
 402   PropertyList_add(&_system_properties, new SystemProperty("java.vm.version", VM_Version::vm_release(),  false));
 403   PropertyList_add(&_system_properties, new SystemProperty("java.vm.name", VM_Version::vm_name(),  false));
 404   PropertyList_add(&_system_properties, new SystemProperty("jdk.debug", VM_Version::jdk_debug_level(),  false));
 405 
 406   // Initialize the vm.info now, but it will need updating after argument parsing.
 407   _vm_info = new SystemProperty("java.vm.info", VM_Version::vm_info_string(), true);
 408 
 409   // Following are JVMTI agent writable properties.
 410   // Properties values are set to nullptr and they are
 411   // os specific they are initialized in os::init_system_properties_values().
 412   _sun_boot_library_path = new SystemProperty("sun.boot.library.path", nullptr,  true);
 413   _java_library_path = new SystemProperty("java.library.path", nullptr,  true);
 414   _java_home =  new SystemProperty("java.home", nullptr,  true);
 415   _java_class_path = new SystemProperty("java.class.path", "",  true);
 416   // jdk.boot.class.path.append is a non-writeable, internal property.
 417   // It can only be set by either:
 418   //    - -Xbootclasspath/a:
 419   //    - AddToBootstrapClassLoaderSearch during JVMTI OnLoad phase
 420   _jdk_boot_class_path_append = new SystemProperty("jdk.boot.class.path.append", nullptr, false, true);
 421 
 422   // Add to System Property list.
 423   PropertyList_add(&_system_properties, _sun_boot_library_path);
 424   PropertyList_add(&_system_properties, _java_library_path);
 425   PropertyList_add(&_system_properties, _java_home);
 426   PropertyList_add(&_system_properties, _java_class_path);
 427   PropertyList_add(&_system_properties, _jdk_boot_class_path_append);
 428   PropertyList_add(&_system_properties, _vm_info);
 429 
 430   // Set OS specific system properties values
 431   os::init_system_properties_values();
 432 }
 433 
 434 // Update/Initialize System properties after JDK version number is known
 435 void Arguments::init_version_specific_system_properties() {
 436   enum { bufsz = 16 };
 437   char buffer[bufsz];
 438   const char* spec_vendor = "Oracle Corporation";
 439   uint32_t spec_version = JDK_Version::current().major_version();
 440 
 441   jio_snprintf(buffer, bufsz, UINT32_FORMAT, spec_version);
 442 
 443   PropertyList_add(&_system_properties,
 444       new SystemProperty("java.vm.specification.vendor",  spec_vendor, false));
 445   PropertyList_add(&_system_properties,
 446       new SystemProperty("java.vm.specification.version", buffer, false));
 447   PropertyList_add(&_system_properties,
 448       new SystemProperty("java.vm.vendor", VM_Version::vm_vendor(),  false));
 449 }
 450 
 451 /*
 452  *  -XX argument processing:
 453  *
 454  *  -XX arguments are defined in several places, such as:
 455  *      globals.hpp, globals_<cpu>.hpp, globals_<os>.hpp, <compiler>_globals.hpp, or <gc>_globals.hpp.
 456  *  -XX arguments are parsed in parse_argument().
 457  *  -XX argument bounds checking is done in check_vm_args_consistency().
 458  *
 459  * Over time -XX arguments may change. There are mechanisms to handle common cases:
 460  *
 461  *      ALIASED: An option that is simply another name for another option. This is often
 462  *               part of the process of deprecating a flag, but not all aliases need
 463  *               to be deprecated.
 464  *
 465  *               Create an alias for an option by adding the old and new option names to the
 466  *               "aliased_jvm_flags" table. Delete the old variable from globals.hpp (etc).
 467  *
 468  *   DEPRECATED: An option that is supported, but a warning is printed to let the user know that
 469  *               support may be removed in the future. Both regular and aliased options may be
 470  *               deprecated.
 471  *
 472  *               Add a deprecation warning for an option (or alias) by adding an entry in the
 473  *               "special_jvm_flags" table and setting the "deprecated_in" field.
 474  *               Often an option "deprecated" in one major release will
 475  *               be made "obsolete" in the next. In this case the entry should also have its
 476  *               "obsolete_in" field set.
 477  *
 478  *     OBSOLETE: An option that has been removed (and deleted from globals.hpp), but is still accepted
 479  *               on the command line. A warning is printed to let the user know that option might not
 480  *               be accepted in the future.
 481  *
 482  *               Add an obsolete warning for an option by adding an entry in the "special_jvm_flags"
 483  *               table and setting the "obsolete_in" field.
 484  *
 485  *      EXPIRED: A deprecated or obsolete option that has an "accept_until" version less than or equal
 486  *               to the current JDK version. The system will flatly refuse to admit the existence of
 487  *               the flag. This allows a flag to die automatically over JDK releases.
 488  *
 489  *               Note that manual cleanup of expired options should be done at major JDK version upgrades:
 490  *                  - Newly expired options should be removed from the special_jvm_flags and aliased_jvm_flags tables.
 491  *                  - Newly obsolete or expired deprecated options should have their global variable
 492  *                    definitions removed (from globals.hpp, etc) and related implementations removed.
 493  *
 494  * Recommended approach for removing options:
 495  *
 496  * To remove options commonly used by customers (e.g. product -XX options), use
 497  * the 3-step model adding major release numbers to the deprecate, obsolete and expire columns.
 498  *
 499  * To remove internal options (e.g. diagnostic, experimental, develop options), use
 500  * a 2-step model adding major release numbers to the obsolete and expire columns.
 501  *
 502  * To change the name of an option, use the alias table as well as a 2-step
 503  * model adding major release numbers to the deprecate and expire columns.
 504  * Think twice about aliasing commonly used customer options.
 505  *
 506  * There are times when it is appropriate to leave a future release number as undefined.
 507  *
 508  * Tests:  Aliases should be tested in VMAliasOptions.java.
 509  *         Deprecated options should be tested in VMDeprecatedOptions.java.
 510  */
 511 
 512 // The special_jvm_flags table declares options that are being deprecated and/or obsoleted. The
 513 // "deprecated_in" or "obsolete_in" fields may be set to "undefined", but not both.
 514 // When the JDK version reaches 'deprecated_in' limit, the JVM will process this flag on
 515 // the command-line as usual, but will issue a warning.
 516 // When the JDK version reaches 'obsolete_in' limit, the JVM will continue accepting this flag on
 517 // the command-line, while issuing a warning and ignoring the flag value.
 518 // Once the JDK version reaches 'expired_in' limit, the JVM will flatly refuse to admit the
 519 // existence of the flag.
 520 //
 521 // MANUAL CLEANUP ON JDK VERSION UPDATES:
 522 // This table ensures that the handling of options will update automatically when the JDK
 523 // version is incremented, but the source code needs to be cleanup up manually:
 524 // - As "deprecated" options age into "obsolete" or "expired" options, the associated "globals"
 525 //   variable should be removed, as well as users of the variable.
 526 // - As "deprecated" options age into "obsolete" options, move the entry into the
 527 //   "Obsolete Flags" section of the table.
 528 // - All expired options should be removed from the table.
 529 static SpecialFlag const special_jvm_flags[] = {
 530   // -------------- Deprecated Flags --------------
 531   // --- Non-alias flags - sorted by obsolete_in then expired_in:
 532   { "AllowRedefinitionToAddDeleteMethods", JDK_Version::jdk(13), JDK_Version::undefined(), JDK_Version::undefined() },
 533   { "FlightRecorder",               JDK_Version::jdk(13), JDK_Version::undefined(), JDK_Version::undefined() },
 534   { "DumpSharedSpaces",             JDK_Version::jdk(18), JDK_Version::jdk(19), JDK_Version::undefined() },
 535   { "DynamicDumpSharedSpaces",      JDK_Version::jdk(18), JDK_Version::jdk(19), JDK_Version::undefined() },
 536   { "RequireSharedSpaces",          JDK_Version::jdk(18), JDK_Version::jdk(19), JDK_Version::undefined() },
 537   { "UseSharedSpaces",              JDK_Version::jdk(18), JDK_Version::jdk(19), JDK_Version::undefined() },
 538 #ifdef _LP64
 539   { "UseCompressedClassPointers",   JDK_Version::jdk(25),  JDK_Version::jdk(27), JDK_Version::undefined() },
 540 #endif
 541   { "ParallelRefProcEnabled",       JDK_Version::jdk(26),  JDK_Version::jdk(27), JDK_Version::jdk(28) },
 542   { "ParallelRefProcBalancingEnabled", JDK_Version::jdk(26),  JDK_Version::jdk(27), JDK_Version::jdk(28) },
 543   { "MaxRAM",                       JDK_Version::jdk(26),  JDK_Version::jdk(27), JDK_Version::jdk(28) },
 544   { "AggressiveHeap",               JDK_Version::jdk(26),  JDK_Version::jdk(27), JDK_Version::jdk(28) },
 545   { "NeverActAsServerClassMachine", JDK_Version::jdk(26),  JDK_Version::jdk(27), JDK_Version::jdk(28) },
 546   { "AlwaysActAsServerClassMachine", JDK_Version::jdk(26),  JDK_Version::jdk(27), JDK_Version::jdk(28) },
 547   // --- Deprecated alias flags (see also aliased_jvm_flags) - sorted by obsolete_in then expired_in:
 548   { "CreateMinidumpOnCrash",        JDK_Version::jdk(9),  JDK_Version::undefined(), JDK_Version::undefined() },
 549 
 550   // -------------- Obsolete Flags - sorted by expired_in --------------
 551 
 552   { "MetaspaceReclaimPolicy",       JDK_Version::undefined(), JDK_Version::jdk(21), JDK_Version::undefined() },
 553 #if defined(AARCH64)
 554   { "NearCpool",                    JDK_Version::undefined(), JDK_Version::jdk(25), JDK_Version::undefined() },
 555 #endif
 556 
 557   { "PSChunkLargeArrays",           JDK_Version::jdk(26),  JDK_Version::jdk(27), JDK_Version::jdk(28) },
 558 
 559 #ifdef ASSERT
 560   { "DummyObsoleteTestFlag",        JDK_Version::undefined(), JDK_Version::jdk(18), JDK_Version::undefined() },
 561 #endif
 562 
 563 #ifdef TEST_VERIFY_SPECIAL_JVM_FLAGS
 564   // These entries will generate build errors.  Their purpose is to test the macros.
 565   { "dep > obs",                    JDK_Version::jdk(9), JDK_Version::jdk(8), JDK_Version::undefined() },
 566   { "dep > exp ",                   JDK_Version::jdk(9), JDK_Version::undefined(), JDK_Version::jdk(8) },
 567   { "obs > exp ",                   JDK_Version::undefined(), JDK_Version::jdk(9), JDK_Version::jdk(8) },
 568   { "obs > exp",                    JDK_Version::jdk(8), JDK_Version::undefined(), JDK_Version::jdk(10) },
 569   { "not deprecated or obsolete",   JDK_Version::undefined(), JDK_Version::undefined(), JDK_Version::jdk(9) },
 570   { "dup option",                   JDK_Version::jdk(9), JDK_Version::undefined(), JDK_Version::undefined() },
 571   { "dup option",                   JDK_Version::jdk(9), JDK_Version::undefined(), JDK_Version::undefined() },
 572 #endif
 573 
 574   { nullptr, JDK_Version(0), JDK_Version(0) }
 575 };
 576 
 577 // Flags that are aliases for other flags.
 578 typedef struct {
 579   const char* alias_name;
 580   const char* real_name;
 581 } AliasedFlag;
 582 
 583 static AliasedFlag const aliased_jvm_flags[] = {
 584   { "CreateMinidumpOnCrash",    "CreateCoredumpOnCrash" },
 585   { nullptr, nullptr}
 586 };
 587 
 588 // Return true if "v" is less than "other", where "other" may be "undefined".
 589 static bool version_less_than(JDK_Version v, JDK_Version other) {
 590   assert(!v.is_undefined(), "must be defined");
 591   if (!other.is_undefined() && v.compare(other) >= 0) {
 592     return false;
 593   } else {
 594     return true;
 595   }
 596 }
 597 
 598 static bool lookup_special_flag(const char *flag_name, SpecialFlag& flag) {
 599   for (size_t i = 0; special_jvm_flags[i].name != nullptr; i++) {
 600     if ((strcmp(special_jvm_flags[i].name, flag_name) == 0)) {
 601       flag = special_jvm_flags[i];
 602       return true;
 603     }
 604   }
 605   return false;
 606 }
 607 
 608 bool Arguments::is_obsolete_flag(const char *flag_name, JDK_Version* version) {
 609   assert(version != nullptr, "Must provide a version buffer");
 610   SpecialFlag flag;
 611   if (lookup_special_flag(flag_name, flag)) {
 612     if (!flag.obsolete_in.is_undefined()) {
 613       if (!version_less_than(JDK_Version::current(), flag.obsolete_in)) {
 614         *version = flag.obsolete_in;
 615         // This flag may have been marked for obsoletion in this version, but we may not
 616         // have actually removed it yet. Rather than ignoring it as soon as we reach
 617         // this version we allow some time for the removal to happen. So if the flag
 618         // still actually exists we process it as normal, but issue an adjusted warning.
 619         const JVMFlag *real_flag = JVMFlag::find_declared_flag(flag_name);
 620         if (real_flag != nullptr) {
 621           char version_str[256];
 622           version->to_string(version_str, sizeof(version_str));
 623           warning("Temporarily processing option %s; support is scheduled for removal in %s",
 624                   flag_name, version_str);
 625           return false;
 626         }
 627         return true;
 628       }
 629     }
 630   }
 631   return false;
 632 }
 633 
 634 int Arguments::is_deprecated_flag(const char *flag_name, JDK_Version* version) {
 635   assert(version != nullptr, "Must provide a version buffer");
 636   SpecialFlag flag;
 637   if (lookup_special_flag(flag_name, flag)) {
 638     if (!flag.deprecated_in.is_undefined()) {
 639       if (version_less_than(JDK_Version::current(), flag.obsolete_in) &&
 640           version_less_than(JDK_Version::current(), flag.expired_in)) {
 641         *version = flag.deprecated_in;
 642         return 1;
 643       } else {
 644         return -1;
 645       }
 646     }
 647   }
 648   return 0;
 649 }
 650 
 651 const char* Arguments::real_flag_name(const char *flag_name) {
 652   for (size_t i = 0; aliased_jvm_flags[i].alias_name != nullptr; i++) {
 653     const AliasedFlag& flag_status = aliased_jvm_flags[i];
 654     if (strcmp(flag_status.alias_name, flag_name) == 0) {
 655         return flag_status.real_name;
 656     }
 657   }
 658   return flag_name;
 659 }
 660 
 661 #ifdef ASSERT
 662 static bool lookup_special_flag(const char *flag_name, size_t skip_index) {
 663   for (size_t i = 0; special_jvm_flags[i].name != nullptr; i++) {
 664     if ((i != skip_index) && (strcmp(special_jvm_flags[i].name, flag_name) == 0)) {
 665       return true;
 666     }
 667   }
 668   return false;
 669 }
 670 
 671 // Verifies the correctness of the entries in the special_jvm_flags table.
 672 // If there is a semantic error (i.e. a bug in the table) such as the obsoletion
 673 // version being earlier than the deprecation version, then a warning is issued
 674 // and verification fails - by returning false. If it is detected that the table
 675 // is out of date, with respect to the current version, then ideally a warning is
 676 // issued but verification does not fail. This allows the VM to operate when the
 677 // version is first updated, without needing to update all the impacted flags at
 678 // the same time. In practice we can't issue the warning immediately when the version
 679 // is updated as it occurs for every test and some tests are not prepared to handle
 680 // unexpected output - see 8196739. Instead we only check if the table is up-to-date
 681 // if the check_globals flag is true, and in addition allow a grace period and only
 682 // check for stale flags when we hit build 25 (which is far enough into the 6 month
 683 // release cycle that all flag updates should have been processed, whilst still
 684 // leaving time to make the change before RDP2).
 685 // We use a gtest to call this, passing true, so that we can detect stale flags before
 686 // the end of the release cycle.
 687 
 688 static const int SPECIAL_FLAG_VALIDATION_BUILD = 25;
 689 
 690 bool Arguments::verify_special_jvm_flags(bool check_globals) {
 691   bool success = true;
 692   for (size_t i = 0; special_jvm_flags[i].name != nullptr; i++) {
 693     const SpecialFlag& flag = special_jvm_flags[i];
 694     if (lookup_special_flag(flag.name, i)) {
 695       warning("Duplicate special flag declaration \"%s\"", flag.name);
 696       success = false;
 697     }
 698     if (flag.deprecated_in.is_undefined() &&
 699         flag.obsolete_in.is_undefined()) {
 700       warning("Special flag entry \"%s\" must declare version deprecated and/or obsoleted in.", flag.name);
 701       success = false;
 702     }
 703 
 704     if (!flag.deprecated_in.is_undefined()) {
 705       if (!version_less_than(flag.deprecated_in, flag.obsolete_in)) {
 706         warning("Special flag entry \"%s\" must be deprecated before obsoleted.", flag.name);
 707         success = false;
 708       }
 709 
 710       if (!version_less_than(flag.deprecated_in, flag.expired_in)) {
 711         warning("Special flag entry \"%s\" must be deprecated before expired.", flag.name);
 712         success = false;
 713       }
 714     }
 715 
 716     if (!flag.obsolete_in.is_undefined()) {
 717       if (!version_less_than(flag.obsolete_in, flag.expired_in)) {
 718         warning("Special flag entry \"%s\" must be obsoleted before expired.", flag.name);
 719         success = false;
 720       }
 721 
 722       // if flag has become obsolete it should not have a "globals" flag defined anymore.
 723       if (check_globals && VM_Version::vm_build_number() >= SPECIAL_FLAG_VALIDATION_BUILD &&
 724           !version_less_than(JDK_Version::current(), flag.obsolete_in)) {
 725         if (JVMFlag::find_declared_flag(flag.name) != nullptr) {
 726           warning("Global variable for obsolete special flag entry \"%s\" should be removed", flag.name);
 727           success = false;
 728         }
 729       }
 730 
 731     } else if (!flag.expired_in.is_undefined()) {
 732       warning("Special flag entry \"%s\" must be explicitly obsoleted before expired.", flag.name);
 733       success = false;
 734     }
 735 
 736     if (!flag.expired_in.is_undefined()) {
 737       // if flag has become expired it should not have a "globals" flag defined anymore.
 738       if (check_globals && VM_Version::vm_build_number() >= SPECIAL_FLAG_VALIDATION_BUILD &&
 739           !version_less_than(JDK_Version::current(), flag.expired_in)) {
 740         if (JVMFlag::find_declared_flag(flag.name) != nullptr) {
 741           warning("Global variable for expired flag entry \"%s\" should be removed", flag.name);
 742           success = false;
 743         }
 744       }
 745     }
 746   }
 747   return success;
 748 }
 749 #endif
 750 
 751 bool Arguments::atojulong(const char *s, julong* result) {
 752   return parse_integer(s, result);
 753 }
 754 
 755 Arguments::ArgsRange Arguments::check_memory_size(julong size, julong min_size, julong max_size) {
 756   if (size < min_size) return arg_too_small;
 757   if (size > max_size) return arg_too_big;
 758   return arg_in_range;
 759 }
 760 
 761 // Describe an argument out of range error
 762 void Arguments::describe_range_error(ArgsRange errcode) {
 763   switch(errcode) {
 764   case arg_too_big:
 765     jio_fprintf(defaultStream::error_stream(),
 766                 "The specified size exceeds the maximum "
 767                 "representable size.\n");
 768     break;
 769   case arg_too_small:
 770   case arg_unreadable:
 771   case arg_in_range:
 772     // do nothing for now
 773     break;
 774   default:
 775     ShouldNotReachHere();
 776   }
 777 }
 778 
 779 static bool set_bool_flag(JVMFlag* flag, bool value, JVMFlagOrigin origin) {
 780   if (JVMFlagAccess::set_bool(flag, &value, origin) == JVMFlag::SUCCESS) {
 781     return true;
 782   } else {
 783     return false;
 784   }
 785 }
 786 
 787 static bool set_fp_numeric_flag(JVMFlag* flag, const char* value, JVMFlagOrigin origin) {
 788   // strtod allows leading whitespace, but our flag format does not.
 789   if (*value == '\0' || isspace((unsigned char) *value)) {
 790     return false;
 791   }
 792   char* end;
 793   errno = 0;
 794   double v = strtod(value, &end);
 795   if ((errno != 0) || (*end != 0)) {
 796     return false;
 797   }
 798   if (g_isnan(v) || !g_isfinite(v)) {
 799     // Currently we cannot handle these special values.
 800     return false;
 801   }
 802 
 803   if (JVMFlagAccess::set_double(flag, &v, origin) == JVMFlag::SUCCESS) {
 804     return true;
 805   }
 806   return false;
 807 }
 808 
 809 static bool set_numeric_flag(JVMFlag* flag, const char* value, JVMFlagOrigin origin) {
 810   JVMFlag::Error result = JVMFlag::WRONG_FORMAT;
 811 
 812   if (flag->is_int()) {
 813     int v;
 814     if (parse_integer(value, &v)) {
 815       result = JVMFlagAccess::set_int(flag, &v, origin);
 816     }
 817   } else if (flag->is_uint()) {
 818     uint v;
 819     if (parse_integer(value, &v)) {
 820       result = JVMFlagAccess::set_uint(flag, &v, origin);
 821     }
 822   } else if (flag->is_intx()) {
 823     intx v;
 824     if (parse_integer(value, &v)) {
 825       result = JVMFlagAccess::set_intx(flag, &v, origin);
 826     }
 827   } else if (flag->is_uintx()) {
 828     uintx v;
 829     if (parse_integer(value, &v)) {
 830       result = JVMFlagAccess::set_uintx(flag, &v, origin);
 831     }
 832   } else if (flag->is_uint64_t()) {
 833     uint64_t v;
 834     if (parse_integer(value, &v)) {
 835       result = JVMFlagAccess::set_uint64_t(flag, &v, origin);
 836     }
 837   } else if (flag->is_size_t()) {
 838     size_t v;
 839     if (parse_integer(value, &v)) {
 840       result = JVMFlagAccess::set_size_t(flag, &v, origin);
 841     }
 842   }
 843 
 844   return result == JVMFlag::SUCCESS;
 845 }
 846 
 847 static bool set_string_flag(JVMFlag* flag, const char* value, JVMFlagOrigin origin) {
 848   if (value[0] == '\0') {
 849     value = nullptr;
 850   }
 851   if (JVMFlagAccess::set_ccstr(flag, &value, origin) != JVMFlag::SUCCESS) return false;
 852   // Contract:  JVMFlag always returns a pointer that needs freeing.
 853   FREE_C_HEAP_ARRAY(char, value);
 854   return true;
 855 }
 856 
 857 static bool append_to_string_flag(JVMFlag* flag, const char* new_value, JVMFlagOrigin origin) {
 858   const char* old_value = "";
 859   if (JVMFlagAccess::get_ccstr(flag, &old_value) != JVMFlag::SUCCESS) return false;
 860   size_t old_len = old_value != nullptr ? strlen(old_value) : 0;
 861   size_t new_len = strlen(new_value);
 862   const char* value;
 863   char* free_this_too = nullptr;
 864   if (old_len == 0) {
 865     value = new_value;
 866   } else if (new_len == 0) {
 867     value = old_value;
 868   } else {
 869      size_t length = old_len + 1 + new_len + 1;
 870      char* buf = NEW_C_HEAP_ARRAY(char, length, mtArguments);
 871     // each new setting adds another LINE to the switch:
 872     jio_snprintf(buf, length, "%s\n%s", old_value, new_value);
 873     value = buf;
 874     free_this_too = buf;
 875   }
 876   (void) JVMFlagAccess::set_ccstr(flag, &value, origin);
 877   // JVMFlag always returns a pointer that needs freeing.
 878   FREE_C_HEAP_ARRAY(char, value);
 879   // JVMFlag made its own copy, so I must delete my own temp. buffer.
 880   FREE_C_HEAP_ARRAY(char, free_this_too);
 881   return true;
 882 }
 883 
 884 const char* Arguments::handle_aliases_and_deprecation(const char* arg) {
 885   const char* real_name = real_flag_name(arg);
 886   JDK_Version since = JDK_Version();
 887   switch (is_deprecated_flag(arg, &since)) {
 888   case -1: {
 889       // Obsolete or expired, so don't process normally,
 890       // but allow for an obsolete flag we're still
 891       // temporarily allowing.
 892       if (!is_obsolete_flag(arg, &since)) {
 893         return real_name;
 894       }
 895       // Note if we're not considered obsolete then we can't be expired either
 896       // as obsoletion must come first.
 897       return nullptr;
 898     }
 899     case 0:
 900       return real_name;
 901     case 1: {
 902       char version[256];
 903       since.to_string(version, sizeof(version));
 904       if (real_name != arg) {
 905         warning("Option %s was deprecated in version %s and will likely be removed in a future release. Use option %s instead.",
 906                 arg, version, real_name);
 907       } else {
 908         warning("Option %s was deprecated in version %s and will likely be removed in a future release.",
 909                 arg, version);
 910       }
 911       return real_name;
 912     }
 913   }
 914   ShouldNotReachHere();
 915   return nullptr;
 916 }
 917 
 918 #define BUFLEN 255
 919 
 920 JVMFlag* Arguments::find_jvm_flag(const char* name, size_t name_length) {
 921   char name_copied[BUFLEN+1];
 922   if (name[name_length] != 0) {
 923     if (name_length > BUFLEN) {
 924       return nullptr;
 925     } else {
 926       strncpy(name_copied, name, name_length);
 927       name_copied[name_length] = '\0';
 928       name = name_copied;
 929     }
 930   }
 931 
 932   const char* real_name = Arguments::handle_aliases_and_deprecation(name);
 933   if (real_name == nullptr) {
 934     return nullptr;
 935   }
 936   JVMFlag* flag = JVMFlag::find_flag(real_name);
 937   return flag;
 938 }
 939 
 940 bool Arguments::parse_argument(const char* arg, JVMFlagOrigin origin) {
 941   bool is_bool = false;
 942   bool bool_val = false;
 943   char c = *arg;
 944   if (c == '+' || c == '-') {
 945     is_bool = true;
 946     bool_val = (c == '+');
 947     arg++;
 948   }
 949 
 950   const char* name = arg;
 951   while (true) {
 952     c = *arg;
 953     if (isalnum(c) || (c == '_')) {
 954       ++arg;
 955     } else {
 956       break;
 957     }
 958   }
 959 
 960   size_t name_len = size_t(arg - name);
 961   if (name_len == 0) {
 962     return false;
 963   }
 964 
 965   JVMFlag* flag = find_jvm_flag(name, name_len);
 966   if (flag == nullptr) {
 967     return false;
 968   }
 969 
 970   if (is_bool) {
 971     if (*arg != 0) {
 972       // Error -- extra characters such as -XX:+BoolFlag=123
 973       return false;
 974     }
 975     return set_bool_flag(flag, bool_val, origin);
 976   }
 977 
 978   if (arg[0] == '=') {
 979     const char* value = arg + 1;
 980     if (flag->is_ccstr()) {
 981       if (flag->ccstr_accumulates()) {
 982         return append_to_string_flag(flag, value, origin);
 983       } else {
 984         return set_string_flag(flag, value, origin);
 985       }
 986     } else if (flag->is_double()) {
 987       return set_fp_numeric_flag(flag, value, origin);
 988     } else {
 989       return set_numeric_flag(flag, value, origin);
 990     }
 991   }
 992 
 993   if (arg[0] == ':' && arg[1] == '=') {
 994     // -XX:Foo:=xxx will reset the string flag to the given value.
 995     const char* value = arg + 2;
 996     return set_string_flag(flag, value, origin);
 997   }
 998 
 999   return false;
1000 }
1001 
1002 void Arguments::add_string(char*** bldarray, int* count, const char* arg) {
1003   assert(bldarray != nullptr, "illegal argument");
1004 
1005   if (arg == nullptr) {
1006     return;
1007   }
1008 
1009   int new_count = *count + 1;
1010 
1011   // expand the array and add arg to the last element
1012   if (*bldarray == nullptr) {
1013     *bldarray = NEW_C_HEAP_ARRAY(char*, new_count, mtArguments);
1014   } else {
1015     *bldarray = REALLOC_C_HEAP_ARRAY(char*, *bldarray, new_count, mtArguments);
1016   }
1017   (*bldarray)[*count] = os::strdup_check_oom(arg);
1018   *count = new_count;
1019 }
1020 
1021 void Arguments::build_jvm_args(const char* arg) {
1022   add_string(&_jvm_args_array, &_num_jvm_args, arg);
1023 }
1024 
1025 void Arguments::build_jvm_flags(const char* arg) {
1026   add_string(&_jvm_flags_array, &_num_jvm_flags, arg);
1027 }
1028 
1029 // utility function to return a string that concatenates all
1030 // strings in a given char** array
1031 const char* Arguments::build_resource_string(char** args, int count) {
1032   if (args == nullptr || count == 0) {
1033     return nullptr;
1034   }
1035   size_t length = 0;
1036   for (int i = 0; i < count; i++) {
1037     length += strlen(args[i]) + 1; // add 1 for a space or null terminating character
1038   }
1039   char* s = NEW_RESOURCE_ARRAY(char, length);
1040   char* dst = s;
1041   for (int j = 0; j < count; j++) {
1042     size_t offset = strlen(args[j]) + 1; // add 1 for a space or null terminating character
1043     jio_snprintf(dst, length, "%s ", args[j]); // jio_snprintf will replace the last space character with null character
1044     dst += offset;
1045     length -= offset;
1046   }
1047   return (const char*) s;
1048 }
1049 
1050 void Arguments::print_on(outputStream* st) {
1051   st->print_cr("VM Arguments:");
1052   if (num_jvm_flags() > 0) {
1053     st->print("jvm_flags: "); print_jvm_flags_on(st);
1054     st->cr();
1055   }
1056   if (num_jvm_args() > 0) {
1057     st->print("jvm_args: "); print_jvm_args_on(st);
1058     st->cr();
1059   }
1060   st->print_cr("java_command: %s", java_command() ? java_command() : "<unknown>");
1061   if (_java_class_path != nullptr) {
1062     char* path = _java_class_path->value();
1063     size_t len = strlen(path);
1064     st->print("java_class_path (initial): ");
1065     // Avoid using st->print_cr() because path length maybe longer than O_BUFLEN.
1066     if (len == 0) {
1067       st->print_raw_cr("<not set>");
1068     } else {
1069       st->print_raw_cr(path, len);
1070     }
1071   }
1072   st->print_cr("Launcher Type: %s", _sun_java_launcher);
1073 }
1074 
1075 void Arguments::print_summary_on(outputStream* st) {
1076   // Print the command line.  Environment variables that are helpful for
1077   // reproducing the problem are written later in the hs_err file.
1078   // flags are from setting file
1079   if (num_jvm_flags() > 0) {
1080     st->print_raw("Settings File: ");
1081     print_jvm_flags_on(st);
1082     st->cr();
1083   }
1084   // args are the command line and environment variable arguments.
1085   st->print_raw("Command Line: ");
1086   if (num_jvm_args() > 0) {
1087     print_jvm_args_on(st);
1088   }
1089   // this is the classfile and any arguments to the java program
1090   if (java_command() != nullptr) {
1091     st->print("%s", java_command());
1092   }
1093   st->cr();
1094 }
1095 
1096 void Arguments::set_jvm_flags_file(const char *value) {
1097   if (_jvm_flags_file != nullptr) {
1098     os::free(_jvm_flags_file);
1099   }
1100   _jvm_flags_file = os::strdup_check_oom(value);
1101 }
1102 
1103 void Arguments::print_jvm_flags_on(outputStream* st) {
1104   if (_num_jvm_flags > 0) {
1105     for (int i=0; i < _num_jvm_flags; i++) {
1106       st->print("%s ", _jvm_flags_array[i]);
1107     }
1108   }
1109 }
1110 
1111 void Arguments::print_jvm_args_on(outputStream* st) {
1112   if (_num_jvm_args > 0) {
1113     for (int i=0; i < _num_jvm_args; i++) {
1114       st->print("%s ", _jvm_args_array[i]);
1115     }
1116   }
1117 }
1118 
1119 bool Arguments::process_argument(const char* arg,
1120                                  jboolean ignore_unrecognized,
1121                                  JVMFlagOrigin origin) {
1122   JDK_Version since = JDK_Version();
1123 
1124   if (parse_argument(arg, origin)) {
1125     return true;
1126   }
1127 
1128   // Determine if the flag has '+', '-', or '=' characters.
1129   bool has_plus_minus = (*arg == '+' || *arg == '-');
1130   const char* const argname = has_plus_minus ? arg + 1 : arg;
1131 
1132   size_t arg_len;
1133   const char* equal_sign = strchr(argname, '=');
1134   if (equal_sign == nullptr) {
1135     arg_len = strlen(argname);
1136   } else {
1137     arg_len = equal_sign - argname;
1138   }
1139 
1140   // Only make the obsolete check for valid arguments.
1141   if (arg_len <= BUFLEN) {
1142     // Construct a string which consists only of the argument name without '+', '-', or '='.
1143     char stripped_argname[BUFLEN+1]; // +1 for '\0'
1144     jio_snprintf(stripped_argname, arg_len+1, "%s", argname); // +1 for '\0'
1145     if (is_obsolete_flag(stripped_argname, &since)) {
1146       char version[256];
1147       since.to_string(version, sizeof(version));
1148       warning("Ignoring option %s; support was removed in %s", stripped_argname, version);
1149       return true;
1150     }
1151   }
1152 
1153   // For locked flags, report a custom error message if available.
1154   // Otherwise, report the standard unrecognized VM option.
1155   const JVMFlag* found_flag = JVMFlag::find_declared_flag((const char*)argname, arg_len);
1156   if (found_flag != nullptr) {
1157     char locked_message_buf[BUFLEN];
1158     JVMFlag::MsgType msg_type = found_flag->get_locked_message(locked_message_buf, BUFLEN);
1159     if (strlen(locked_message_buf) != 0) {
1160 #ifdef PRODUCT
1161       bool mismatched = msg_type == JVMFlag::DEVELOPER_FLAG_BUT_PRODUCT_BUILD;
1162       if (ignore_unrecognized && mismatched) {
1163         return true;
1164       }
1165 #endif
1166       jio_fprintf(defaultStream::error_stream(), "%s", locked_message_buf);
1167     }
1168     if (found_flag->is_bool() && !has_plus_minus) {
1169       jio_fprintf(defaultStream::error_stream(),
1170         "Missing +/- setting for VM option '%s'\n", argname);
1171     } else if (!found_flag->is_bool() && has_plus_minus) {
1172       jio_fprintf(defaultStream::error_stream(),
1173         "Unexpected +/- setting in VM option '%s'\n", argname);
1174     } else {
1175       jio_fprintf(defaultStream::error_stream(),
1176         "Improperly specified VM option '%s'\n", argname);
1177     }
1178   } else {
1179     if (ignore_unrecognized) {
1180       return true;
1181     }
1182     jio_fprintf(defaultStream::error_stream(),
1183                 "Unrecognized VM option '%s'\n", argname);
1184     JVMFlag* fuzzy_matched = JVMFlag::fuzzy_match((const char*)argname, arg_len, true);
1185     if (fuzzy_matched != nullptr) {
1186       jio_fprintf(defaultStream::error_stream(),
1187                   "Did you mean '%s%s%s'?\n",
1188                   (fuzzy_matched->is_bool()) ? "(+/-)" : "",
1189                   fuzzy_matched->name(),
1190                   (fuzzy_matched->is_bool()) ? "" : "=<value>");
1191     }
1192   }
1193 
1194   // allow for commandline "commenting out" options like -XX:#+Verbose
1195   return arg[0] == '#';
1196 }
1197 
1198 bool Arguments::process_settings_file(const char* file_name, bool should_exist, jboolean ignore_unrecognized) {
1199   FILE* stream = os::fopen(file_name, "rb");
1200   if (stream == nullptr) {
1201     if (should_exist) {
1202       jio_fprintf(defaultStream::error_stream(),
1203                   "Could not open settings file %s\n", file_name);
1204       return false;
1205     } else {
1206       return true;
1207     }
1208   }
1209 
1210   char token[1024];
1211   size_t pos = 0;
1212 
1213   bool in_white_space = true;
1214   bool in_comment     = false;
1215   bool in_quote       = false;
1216   char quote_c        = 0;
1217   bool result         = true;
1218 
1219   int c_or_eof = getc(stream);
1220   while (c_or_eof != EOF && pos < (sizeof(token) - 1)) {
1221     // We have checked the c_or_eof for EOF. getc should only ever return the
1222     // EOF or an unsigned char converted to an int. We cast down to a char to
1223     // avoid the char to int promotions we would otherwise do in the comparisons
1224     // below (which would be incorrect if we ever compared to a non-ascii char),
1225     // and the int to char conversions we would otherwise do in the assignments.
1226     const char c = static_cast<char>(c_or_eof);
1227     if (in_white_space) {
1228       if (in_comment) {
1229         if (c == '\n') in_comment = false;
1230       } else {
1231         if (c == '#') in_comment = true;
1232         else if (!isspace((unsigned char) c)) {
1233           in_white_space = false;
1234           token[pos++] = c;
1235         }
1236       }
1237     } else {
1238       if (c == '\n' || (!in_quote && isspace((unsigned char) c))) {
1239         // token ends at newline, or at unquoted whitespace
1240         // this allows a way to include spaces in string-valued options
1241         token[pos] = '\0';
1242         logOption(token);
1243         result &= process_argument(token, ignore_unrecognized, JVMFlagOrigin::CONFIG_FILE);
1244         build_jvm_flags(token);
1245         pos = 0;
1246         in_white_space = true;
1247         in_quote = false;
1248       } else if (!in_quote && (c == '\'' || c == '"')) {
1249         in_quote = true;
1250         quote_c = c;
1251       } else if (in_quote && (c == quote_c)) {
1252         in_quote = false;
1253       } else {
1254         token[pos++] = c;
1255       }
1256     }
1257     c_or_eof = getc(stream);
1258   }
1259   if (pos > 0) {
1260     token[pos] = '\0';
1261     result &= process_argument(token, ignore_unrecognized, JVMFlagOrigin::CONFIG_FILE);
1262     build_jvm_flags(token);
1263   }
1264   fclose(stream);
1265   return result;
1266 }
1267 
1268 //=============================================================================================================
1269 // Parsing of properties (-D)
1270 
1271 const char* Arguments::get_property(const char* key) {
1272   return PropertyList_get_value(system_properties(), key);
1273 }
1274 
1275 bool Arguments::add_property(const char* prop, PropertyWriteable writeable, PropertyInternal internal) {
1276   const char* eq = strchr(prop, '=');
1277   const char* key;
1278   const char* value = "";
1279 
1280   if (eq == nullptr) {
1281     // property doesn't have a value, thus use passed string
1282     key = prop;
1283   } else {
1284     // property have a value, thus extract it and save to the
1285     // allocated string
1286     size_t key_len = eq - prop;
1287     char* tmp_key = AllocateHeap(key_len + 1, mtArguments);
1288 
1289     jio_snprintf(tmp_key, key_len + 1, "%s", prop);
1290     key = tmp_key;
1291 
1292     value = &prop[key_len + 1];
1293   }
1294 
1295   if (internal == ExternalProperty) {
1296     CDSConfig::check_incompatible_property(key, value);
1297   }
1298 
1299   if (strcmp(key, "java.compiler") == 0) {
1300     // we no longer support java.compiler system property, log a warning and let it get
1301     // passed to Java, like any other system property
1302     if (strlen(value) == 0 || strcasecmp(value, "NONE") == 0) {
1303         // for applications using NONE or empty value, log a more informative message
1304         warning("The java.compiler system property is obsolete and no longer supported, use -Xint");
1305     } else {
1306         warning("The java.compiler system property is obsolete and no longer supported.");
1307     }
1308   } else if (strcmp(key, "sun.boot.library.path") == 0) {
1309     // append is true, writable is true, internal is false
1310     PropertyList_unique_add(&_system_properties, key, value, AppendProperty,
1311                             WriteableProperty, ExternalProperty);
1312   } else {
1313     if (strcmp(key, "sun.java.command") == 0) {
1314       char *old_java_command = _java_command;
1315       _java_command = os::strdup_check_oom(value, mtArguments);
1316       if (old_java_command != nullptr) {
1317         os::free(old_java_command);
1318       }
1319     } else if (strcmp(key, "java.vendor.url.bug") == 0) {
1320       // If this property is set on the command line then its value will be
1321       // displayed in VM error logs as the URL at which to submit such logs.
1322       // Normally the URL displayed in error logs is different from the value
1323       // of this system property, so a different property should have been
1324       // used here, but we leave this as-is in case someone depends upon it.
1325       const char* old_java_vendor_url_bug = _java_vendor_url_bug;
1326       // save it in _java_vendor_url_bug, so JVM fatal error handler can access
1327       // its value without going through the property list or making a Java call.
1328       _java_vendor_url_bug = os::strdup_check_oom(value, mtArguments);
1329       if (old_java_vendor_url_bug != nullptr) {
1330         os::free((void *)old_java_vendor_url_bug);
1331       }
1332     }
1333 
1334     // Create new property and add at the end of the list
1335     PropertyList_unique_add(&_system_properties, key, value, AddProperty, writeable, internal);
1336   }
1337 
1338   if (key != prop) {
1339     // SystemProperty copy passed value, thus free previously allocated
1340     // memory
1341     FreeHeap((void *)key);
1342   }
1343 
1344   return true;
1345 }
1346 
1347 //===========================================================================================================
1348 // Setting int/mixed/comp mode flags
1349 
1350 void Arguments::set_mode_flags(Mode mode) {
1351   // Set up default values for all flags.
1352   // If you add a flag to any of the branches below,
1353   // add a default value for it here.
1354   _mode                      = mode;
1355 
1356   // Ensure Agent_OnLoad has the correct initial values.
1357   // This may not be the final mode; mode may change later in onload phase.
1358   PropertyList_unique_add(&_system_properties, "java.vm.info",
1359                           VM_Version::vm_info_string(), AddProperty, UnwriteableProperty, ExternalProperty);
1360 
1361   UseInterpreter             = true;
1362   UseCompiler                = true;
1363   UseLoopCounter             = true;
1364 
1365   // Default values may be platform/compiler dependent -
1366   // use the saved values
1367   ClipInlining               = Arguments::_ClipInlining;
1368   AlwaysCompileLoopMethods   = Arguments::_AlwaysCompileLoopMethods;
1369   UseOnStackReplacement      = Arguments::_UseOnStackReplacement;
1370   BackgroundCompilation      = Arguments::_BackgroundCompilation;
1371 
1372   // Change from defaults based on mode
1373   switch (mode) {
1374   default:
1375     ShouldNotReachHere();
1376     break;
1377   case _int:
1378     UseCompiler              = false;
1379     UseLoopCounter           = false;
1380     AlwaysCompileLoopMethods = false;
1381     UseOnStackReplacement    = false;
1382     break;
1383   case _mixed:
1384     // same as default
1385     break;
1386   case _comp:
1387     UseInterpreter           = false;
1388     BackgroundCompilation    = false;
1389     ClipInlining             = false;
1390     break;
1391   }
1392 }
1393 
1394 // Conflict: required to use shared spaces (-Xshare:on), but
1395 // incompatible command line options were chosen.
1396 void Arguments::no_shared_spaces(const char* message) {
1397   if (RequireSharedSpaces) {
1398     aot_log_error(aot)("%s is incompatible with other specified options.",
1399                    CDSConfig::new_aot_flags_used() ? "AOT cache" : "CDS");
1400     if (CDSConfig::new_aot_flags_used()) {
1401       vm_exit_during_initialization("Unable to use AOT cache", message);
1402     } else {
1403       vm_exit_during_initialization("Unable to use shared archive", message);
1404     }
1405   } else {
1406     if (CDSConfig::new_aot_flags_used()) {
1407       log_warning(aot)("Unable to use AOT cache: %s", message);
1408     } else {
1409       aot_log_info(aot)("Unable to use shared archive: %s", message);
1410     }
1411     UseSharedSpaces = false;
1412   }
1413 }
1414 
1415 static void set_object_alignment() {
1416   // Object alignment.
1417   assert(is_power_of_2(ObjectAlignmentInBytes), "ObjectAlignmentInBytes must be power of 2");
1418   MinObjAlignmentInBytes     = ObjectAlignmentInBytes;
1419   assert(MinObjAlignmentInBytes >= HeapWordsPerLong * HeapWordSize, "ObjectAlignmentInBytes value is too small");
1420   MinObjAlignment            = MinObjAlignmentInBytes / HeapWordSize;
1421   assert(MinObjAlignmentInBytes == MinObjAlignment * HeapWordSize, "ObjectAlignmentInBytes value is incorrect");
1422   MinObjAlignmentInBytesMask = MinObjAlignmentInBytes - 1;
1423 
1424   LogMinObjAlignmentInBytes  = exact_log2(ObjectAlignmentInBytes);
1425   LogMinObjAlignment         = LogMinObjAlignmentInBytes - LogHeapWordSize;
1426 
1427   // Oop encoding heap max
1428   OopEncodingHeapMax = (uint64_t(max_juint) + 1) << LogMinObjAlignmentInBytes;
1429 }
1430 
1431 size_t Arguments::max_heap_for_compressed_oops() {
1432   // Avoid sign flip.
1433   assert(OopEncodingHeapMax > (uint64_t)os::vm_page_size(), "Unusual page size");
1434   // We need to fit both the null page and the heap into the memory budget, while
1435   // keeping alignment constraints of the heap. To guarantee the latter, as the
1436   // null page is located before the heap, we pad the null page to the conservative
1437   // maximum alignment that the GC may ever impose upon the heap.
1438   size_t displacement_due_to_null_page = align_up(os::vm_page_size(),
1439                                                   _conservative_max_heap_alignment);
1440 
1441   LP64_ONLY(return OopEncodingHeapMax - displacement_due_to_null_page);
1442   NOT_LP64(ShouldNotReachHere(); return 0);
1443 }
1444 
1445 void Arguments::set_use_compressed_oops() {
1446 #ifdef _LP64
1447   // MaxHeapSize is not set up properly at this point, but
1448   // the only value that can override MaxHeapSize if we are
1449   // to use UseCompressedOops are InitialHeapSize and MinHeapSize.
1450   size_t max_heap_size = MAX3(MaxHeapSize, InitialHeapSize, MinHeapSize);
1451 
1452   if (max_heap_size <= max_heap_for_compressed_oops()) {
1453     if (FLAG_IS_DEFAULT(UseCompressedOops)) {
1454       FLAG_SET_ERGO(UseCompressedOops, true);
1455     }
1456   } else {
1457     if (UseCompressedOops && !FLAG_IS_DEFAULT(UseCompressedOops)) {
1458       warning("Max heap size too large for Compressed Oops");
1459       FLAG_SET_DEFAULT(UseCompressedOops, false);
1460     }
1461   }
1462 #endif // _LP64
1463 }
1464 
1465 void Arguments::set_conservative_max_heap_alignment() {
1466   // The conservative maximum required alignment for the heap is the maximum of
1467   // the alignments imposed by several sources: any requirements from the heap
1468   // itself and the maximum page size we may run the VM with.
1469   size_t heap_alignment = GCConfig::arguments()->conservative_max_heap_alignment();
1470   _conservative_max_heap_alignment = MAX3(heap_alignment,
1471                                           os::vm_allocation_granularity(),
1472                                           os::max_page_size());
1473   assert(is_power_of_2(_conservative_max_heap_alignment), "Expected to be a power-of-2");
1474 }
1475 
1476 jint Arguments::set_ergonomics_flags() {
1477   GCConfig::initialize();
1478 
1479   set_conservative_max_heap_alignment();
1480 
1481 #ifdef _LP64
1482   set_use_compressed_oops();
1483 
1484   // Also checks that certain machines are slower with compressed oops
1485   // in vm_version initialization code.
1486 #endif // _LP64
1487 
1488   return JNI_OK;
1489 }
1490 
1491 size_t Arguments::limit_heap_by_allocatable_memory(size_t limit) {
1492   // The AggressiveHeap check is a temporary workaround to avoid calling
1493   // GCarguments::heap_virtual_to_physical_ratio() before a GC has been
1494   // selected. This works because AggressiveHeap implies UseParallelGC
1495   // where we know the ratio will be 1. Once the AggressiveHeap option is
1496   // removed, this can be cleaned up.
1497   size_t heap_virtual_to_physical_ratio = (AggressiveHeap ? 1 : GCConfig::arguments()->heap_virtual_to_physical_ratio());
1498   size_t fraction = MaxVirtMemFraction * heap_virtual_to_physical_ratio;
1499   size_t max_allocatable = os::commit_memory_limit();
1500 
1501   return MIN2(limit, max_allocatable / fraction);
1502 }
1503 
1504 // Use static initialization to get the default before parsing
1505 static const size_t DefaultHeapBaseMinAddress = HeapBaseMinAddress;
1506 
1507 static size_t clamp_by_size_t_max(uint64_t value) {
1508   return (size_t)MIN2(value, (uint64_t)std::numeric_limits<size_t>::max());
1509 }
1510 
1511 void Arguments::set_heap_size() {
1512   // Check if the user has configured any limit on the amount of RAM we may use.
1513   bool has_ram_limit = !FLAG_IS_DEFAULT(MaxRAMPercentage) ||
1514                        !FLAG_IS_DEFAULT(MinRAMPercentage) ||
1515                        !FLAG_IS_DEFAULT(InitialRAMPercentage) ||
1516                        !FLAG_IS_DEFAULT(MaxRAM);
1517 
1518   if (FLAG_IS_DEFAULT(MaxRAM)) {
1519     if (CompilerConfig::should_set_client_emulation_mode_flags()) {
1520       // Limit the available memory if client emulation mode is enabled.
1521       FLAG_SET_ERGO(MaxRAM, 1ULL*G);
1522     } else {
1523       // Use the available physical memory on the system.
1524       FLAG_SET_ERGO(MaxRAM, os::physical_memory());
1525     }
1526   }
1527 
1528   // If the maximum heap size has not been set with -Xmx, then set it as
1529   // fraction of the size of physical memory, respecting the maximum and
1530   // minimum sizes of the heap.
1531   if (FLAG_IS_DEFAULT(MaxHeapSize)) {
1532     uint64_t min_memory = (uint64_t)(((double)MaxRAM * MinRAMPercentage) / 100);
1533     uint64_t max_memory = (uint64_t)(((double)MaxRAM * MaxRAMPercentage) / 100);
1534 
1535     const size_t reasonable_min = clamp_by_size_t_max(min_memory);
1536     size_t reasonable_max = clamp_by_size_t_max(max_memory);
1537 
1538     if (reasonable_min < MaxHeapSize) {
1539       // Small physical memory, so use a minimum fraction of it for the heap
1540       reasonable_max = reasonable_min;
1541     } else {
1542       // Not-small physical memory, so require a heap at least
1543       // as large as MaxHeapSize
1544       reasonable_max = MAX2(reasonable_max, MaxHeapSize);
1545     }
1546 
1547     if (!FLAG_IS_DEFAULT(ErgoHeapSizeLimit) && ErgoHeapSizeLimit != 0) {
1548       // Limit the heap size to ErgoHeapSizeLimit
1549       reasonable_max = MIN2(reasonable_max, ErgoHeapSizeLimit);
1550     }
1551 
1552     reasonable_max = limit_heap_by_allocatable_memory(reasonable_max);
1553 
1554     if (!FLAG_IS_DEFAULT(InitialHeapSize)) {
1555       // An initial heap size was specified on the command line,
1556       // so be sure that the maximum size is consistent.  Done
1557       // after call to limit_heap_by_allocatable_memory because that
1558       // method might reduce the allocation size.
1559       reasonable_max = MAX2(reasonable_max, InitialHeapSize);
1560     } else if (!FLAG_IS_DEFAULT(MinHeapSize)) {
1561       reasonable_max = MAX2(reasonable_max, MinHeapSize);
1562     }
1563 
1564 #ifdef _LP64
1565     if (UseCompressedOops || UseCompressedClassPointers) {
1566       // HeapBaseMinAddress can be greater than default but not less than.
1567       if (!FLAG_IS_DEFAULT(HeapBaseMinAddress)) {
1568         if (HeapBaseMinAddress < DefaultHeapBaseMinAddress) {
1569           // matches compressed oops printing flags
1570           log_debug(gc, heap, coops)("HeapBaseMinAddress must be at least %zu "
1571                                      "(%zuG) which is greater than value given %zu",
1572                                      DefaultHeapBaseMinAddress,
1573                                      DefaultHeapBaseMinAddress/G,
1574                                      HeapBaseMinAddress);
1575           FLAG_SET_ERGO(HeapBaseMinAddress, DefaultHeapBaseMinAddress);
1576         }
1577       }
1578     }
1579 
1580     if (UseCompressedOops) {
1581       uintptr_t heap_end = HeapBaseMinAddress + MaxHeapSize;
1582       uintptr_t max_coop_heap = max_heap_for_compressed_oops();
1583 
1584       // Limit the heap size to the maximum possible when using compressed oops
1585       if (heap_end < max_coop_heap) {
1586         // Heap should be above HeapBaseMinAddress to get zero based compressed
1587         // oops but it should be not less than default MaxHeapSize.
1588         max_coop_heap -= HeapBaseMinAddress;
1589       }
1590 
1591       // If the user has configured any limit on the amount of RAM we may use,
1592       // then disable compressed oops if the calculated max exceeds max_coop_heap
1593       // and UseCompressedOops was not specified.
1594       if (reasonable_max > max_coop_heap) {
1595         if (FLAG_IS_ERGO(UseCompressedOops) && has_ram_limit) {
1596           log_debug(gc, heap, coops)("UseCompressedOops disabled due to "
1597                                      "max heap %zu > compressed oop heap %zu. "
1598                                      "Please check the setting of MaxRAMPercentage %5.2f.",
1599                                      reasonable_max, (size_t)max_coop_heap, MaxRAMPercentage);
1600           FLAG_SET_ERGO(UseCompressedOops, false);
1601         } else {
1602           reasonable_max = max_coop_heap;
1603         }
1604       }
1605     }
1606 #endif // _LP64
1607 
1608     log_trace(gc, heap)("  Maximum heap size %zu", reasonable_max);
1609     FLAG_SET_ERGO(MaxHeapSize, reasonable_max);
1610   }
1611 
1612   // If the minimum or initial heap_size have not been set or requested to be set
1613   // ergonomically, set them accordingly.
1614   if (InitialHeapSize == 0 || MinHeapSize == 0) {
1615     size_t reasonable_minimum = clamp_by_size_t_max((uint64_t)OldSize + (uint64_t)NewSize);
1616     reasonable_minimum = MIN2(reasonable_minimum, MaxHeapSize);
1617     reasonable_minimum = limit_heap_by_allocatable_memory(reasonable_minimum);
1618 
1619     if (InitialHeapSize == 0) {
1620       uint64_t initial_memory = (uint64_t)(((double)MaxRAM * InitialRAMPercentage) / 100);
1621       size_t reasonable_initial = clamp_by_size_t_max(initial_memory);
1622       reasonable_initial = limit_heap_by_allocatable_memory(reasonable_initial);
1623 
1624       reasonable_initial = MAX3(reasonable_initial, reasonable_minimum, MinHeapSize);
1625       reasonable_initial = MIN2(reasonable_initial, MaxHeapSize);
1626 
1627       FLAG_SET_ERGO(InitialHeapSize, (size_t)reasonable_initial);
1628       log_trace(gc, heap)("  Initial heap size %zu", InitialHeapSize);
1629     }
1630 
1631     // If the minimum heap size has not been set (via -Xms or -XX:MinHeapSize),
1632     // synchronize with InitialHeapSize to avoid errors with the default value.
1633     if (MinHeapSize == 0) {
1634       FLAG_SET_ERGO(MinHeapSize, MIN2(reasonable_minimum, InitialHeapSize));
1635       log_trace(gc, heap)("  Minimum heap size %zu", MinHeapSize);
1636     }
1637   }
1638 }
1639 
1640 // This option inspects the machine and attempts to set various
1641 // parameters to be optimal for long-running, memory allocation
1642 // intensive jobs.  It is intended for machines with large
1643 // amounts of cpu and memory.
1644 jint Arguments::set_aggressive_heap_flags() {
1645   // initHeapSize is needed since _initial_heap_size is 4 bytes on a 32 bit
1646   // VM, but we may not be able to represent the total physical memory
1647   // available (like having 8gb of memory on a box but using a 32bit VM).
1648   // Thus, we need to make sure we're using a julong for intermediate
1649   // calculations.
1650   julong initHeapSize;
1651   physical_memory_size_type phys_mem = os::physical_memory();
1652   julong total_memory = static_cast<julong>(phys_mem);
1653 
1654   if (total_memory < (julong) 256 * M) {
1655     jio_fprintf(defaultStream::error_stream(),
1656             "You need at least 256mb of memory to use -XX:+AggressiveHeap\n");
1657     vm_exit(1);
1658   }
1659 
1660   // The heap size is half of available memory, or (at most)
1661   // all of possible memory less 160mb (leaving room for the OS
1662   // when using ISM).  This is the maximum; because adaptive sizing
1663   // is turned on below, the actual space used may be smaller.
1664 
1665   initHeapSize = MIN2(total_memory / (julong) 2,
1666           total_memory - (julong) 160 * M);
1667 
1668   initHeapSize = limit_heap_by_allocatable_memory(initHeapSize);
1669 
1670   if (FLAG_IS_DEFAULT(MaxHeapSize)) {
1671     if (FLAG_SET_CMDLINE(MaxHeapSize, initHeapSize) != JVMFlag::SUCCESS) {
1672       return JNI_EINVAL;
1673     }
1674     if (FLAG_SET_CMDLINE(InitialHeapSize, initHeapSize) != JVMFlag::SUCCESS) {
1675       return JNI_EINVAL;
1676     }
1677     if (FLAG_SET_CMDLINE(MinHeapSize, initHeapSize) != JVMFlag::SUCCESS) {
1678       return JNI_EINVAL;
1679     }
1680   }
1681   if (FLAG_IS_DEFAULT(NewSize)) {
1682     // Make the young generation 3/8ths of the total heap.
1683     if (FLAG_SET_CMDLINE(NewSize,
1684             ((julong) MaxHeapSize / (julong) 8) * (julong) 3) != JVMFlag::SUCCESS) {
1685       return JNI_EINVAL;
1686     }
1687     if (FLAG_SET_CMDLINE(MaxNewSize, NewSize) != JVMFlag::SUCCESS) {
1688       return JNI_EINVAL;
1689     }
1690   }
1691 
1692 #if !defined(_ALLBSD_SOURCE) && !defined(AIX)  // UseLargePages is not yet supported on BSD and AIX.
1693   FLAG_SET_DEFAULT(UseLargePages, true);
1694 #endif
1695 
1696   // Increase some data structure sizes for efficiency
1697   if (FLAG_SET_CMDLINE(ResizeTLAB, false) != JVMFlag::SUCCESS) {
1698     return JNI_EINVAL;
1699   }
1700   if (FLAG_SET_CMDLINE(TLABSize, 256 * K) != JVMFlag::SUCCESS) {
1701     return JNI_EINVAL;
1702   }
1703 
1704   // See the OldPLABSize comment below, but replace 'after promotion'
1705   // with 'after copying'.  YoungPLABSize is the size of the survivor
1706   // space per-gc-thread buffers.  The default is 4kw.
1707   if (FLAG_SET_CMDLINE(YoungPLABSize, 256 * K) != JVMFlag::SUCCESS) { // Note: this is in words
1708     return JNI_EINVAL;
1709   }
1710 
1711   // OldPLABSize is the size of the buffers in the old gen that
1712   // UseParallelGC uses to promote live data that doesn't fit in the
1713   // survivor spaces.  At any given time, there's one for each gc thread.
1714   // The default size is 1kw. These buffers are rarely used, since the
1715   // survivor spaces are usually big enough.  For specjbb, however, there
1716   // are occasions when there's lots of live data in the young gen
1717   // and we end up promoting some of it.  We don't have a definite
1718   // explanation for why bumping OldPLABSize helps, but the theory
1719   // is that a bigger PLAB results in retaining something like the
1720   // original allocation order after promotion, which improves mutator
1721   // locality.  A minor effect may be that larger PLABs reduce the
1722   // number of PLAB allocation events during gc.  The value of 8kw
1723   // was arrived at by experimenting with specjbb.
1724   if (FLAG_SET_CMDLINE(OldPLABSize, 8 * K) != JVMFlag::SUCCESS) { // Note: this is in words
1725     return JNI_EINVAL;
1726   }
1727 
1728   // Enable parallel GC and adaptive generation sizing
1729   if (FLAG_SET_CMDLINE(UseParallelGC, true) != JVMFlag::SUCCESS) {
1730     return JNI_EINVAL;
1731   }
1732 
1733   // Encourage steady state memory management
1734   if (FLAG_SET_CMDLINE(ThresholdTolerance, 100) != JVMFlag::SUCCESS) {
1735     return JNI_EINVAL;
1736   }
1737 
1738   return JNI_OK;
1739 }
1740 
1741 // This must be called after ergonomics.
1742 void Arguments::set_bytecode_flags() {
1743   if (!RewriteBytecodes) {
1744     FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
1745   }
1746 }
1747 
1748 // Aggressive optimization flags
1749 jint Arguments::set_aggressive_opts_flags() {
1750 #ifdef COMPILER2
1751   if (AggressiveUnboxing) {
1752     if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
1753       FLAG_SET_DEFAULT(EliminateAutoBox, true);
1754     } else if (!EliminateAutoBox) {
1755       // warning("AggressiveUnboxing is disabled because EliminateAutoBox is disabled");
1756       AggressiveUnboxing = false;
1757     }
1758     if (FLAG_IS_DEFAULT(DoEscapeAnalysis)) {
1759       FLAG_SET_DEFAULT(DoEscapeAnalysis, true);
1760     } else if (!DoEscapeAnalysis) {
1761       // warning("AggressiveUnboxing is disabled because DoEscapeAnalysis is disabled");
1762       AggressiveUnboxing = false;
1763     }
1764   }
1765   if (!FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
1766     if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
1767       FLAG_SET_DEFAULT(EliminateAutoBox, true);
1768     }
1769     // Feed the cache size setting into the JDK
1770     char buffer[1024];
1771     jio_snprintf(buffer, 1024, "java.lang.Integer.IntegerCache.high=%zd", AutoBoxCacheMax);
1772     if (!add_property(buffer)) {
1773       return JNI_ENOMEM;
1774     }
1775   }
1776 #endif
1777 
1778   return JNI_OK;
1779 }
1780 
1781 //===========================================================================================================
1782 
1783 void Arguments::process_java_launcher_argument(const char* launcher, void* extra_info) {
1784   if (_sun_java_launcher != _default_java_launcher) {
1785     os::free(const_cast<char*>(_sun_java_launcher));
1786   }
1787   _sun_java_launcher = os::strdup_check_oom(launcher);
1788 }
1789 
1790 bool Arguments::created_by_java_launcher() {
1791   assert(_sun_java_launcher != nullptr, "property must have value");
1792   return strcmp(DEFAULT_JAVA_LAUNCHER, _sun_java_launcher) != 0;
1793 }
1794 
1795 bool Arguments::executing_unit_tests() {
1796   return _executing_unit_tests;
1797 }
1798 
1799 //===========================================================================================================
1800 // Parsing of main arguments
1801 
1802 static unsigned int addreads_count = 0;
1803 static unsigned int addexports_count = 0;
1804 static unsigned int addopens_count = 0;
1805 static unsigned int patch_mod_count = 0;
1806 static unsigned int enable_native_access_count = 0;
1807 static unsigned int enable_final_field_mutation = 0;
1808 static bool patch_mod_javabase = false;
1809 
1810 // Check the consistency of vm_init_args
1811 bool Arguments::check_vm_args_consistency() {
1812   // This may modify compiler flags. Must be called before CompilerConfig::check_args_consistency()
1813   if (!CDSConfig::check_vm_args_consistency(patch_mod_javabase, mode_flag_cmd_line)) {
1814     return false;
1815   }
1816 
1817   // Method for adding checks for flag consistency.
1818   // The intent is to warn the user of all possible conflicts,
1819   // before returning an error.
1820   // Note: Needs platform-dependent factoring.
1821   bool status = true;
1822 
1823   if (TLABRefillWasteFraction == 0) {
1824     jio_fprintf(defaultStream::error_stream(),
1825                 "TLABRefillWasteFraction should be a denominator, "
1826                 "not %zu\n",
1827                 TLABRefillWasteFraction);
1828     status = false;
1829   }
1830 
1831   status = CompilerConfig::check_args_consistency(status);
1832 #if INCLUDE_JVMCI
1833   if (status && EnableJVMCI) {
1834     // Add the JVMCI module if not using libjvmci or EnableJVMCI
1835     // was explicitly set on the command line or in the jimage.
1836     if ((!UseJVMCINativeLibrary || FLAG_IS_CMDLINE(EnableJVMCI) || FLAG_IS_JIMAGE_RESOURCE(EnableJVMCI)) && ClassLoader::is_module_observable("jdk.internal.vm.ci") && !_jvmci_module_added) {
1837       if (!create_numbered_module_property("jdk.module.addmods", "jdk.internal.vm.ci", _addmods_count++)) {
1838         return false;
1839       }
1840     }
1841   }
1842 #endif
1843 
1844 #if INCLUDE_JFR
1845   if (status && (FlightRecorderOptions || StartFlightRecording)) {
1846     if (!create_numbered_module_property("jdk.module.addmods", "jdk.jfr", _addmods_count++)) {
1847       return false;
1848     }
1849   }
1850 #endif
1851 
1852 #ifndef SUPPORT_RESERVED_STACK_AREA
1853   if (StackReservedPages != 0) {
1854     FLAG_SET_CMDLINE(StackReservedPages, 0);
1855     warning("Reserved Stack Area not supported on this platform");
1856   }
1857 #endif
1858 
1859   return status;
1860 }
1861 
1862 bool Arguments::is_bad_option(const JavaVMOption* option, jboolean ignore,
1863   const char* option_type) {
1864   if (ignore) return false;
1865 
1866   const char* spacer = " ";
1867   if (option_type == nullptr) {
1868     option_type = ++spacer; // Set both to the empty string.
1869   }
1870 
1871   jio_fprintf(defaultStream::error_stream(),
1872               "Unrecognized %s%soption: %s\n", option_type, spacer,
1873               option->optionString);
1874   return true;
1875 }
1876 
1877 static const char* user_assertion_options[] = {
1878   "-da", "-ea", "-disableassertions", "-enableassertions", nullptr
1879 };
1880 
1881 static const char* system_assertion_options[] = {
1882   "-dsa", "-esa", "-disablesystemassertions", "-enablesystemassertions", nullptr
1883 };
1884 
1885 bool Arguments::parse_uint(const char* value,
1886                            uint* uint_arg,
1887                            uint min_size) {
1888   uint n;
1889   if (!parse_integer(value, &n)) {
1890     return false;
1891   }
1892   if (n >= min_size) {
1893     *uint_arg = n;
1894     return true;
1895   } else {
1896     return false;
1897   }
1898 }
1899 
1900 bool Arguments::create_module_property(const char* prop_name, const char* prop_value, PropertyInternal internal) {
1901   assert(is_internal_module_property(prop_name), "unknown module property: '%s'", prop_name);
1902   CDSConfig::check_internal_module_property(prop_name, prop_value);
1903   size_t prop_len = strlen(prop_name) + strlen(prop_value) + 2;
1904   char* property = AllocateHeap(prop_len, mtArguments);
1905   int ret = jio_snprintf(property, prop_len, "%s=%s", prop_name, prop_value);
1906   if (ret < 0 || ret >= (int)prop_len) {
1907     FreeHeap(property);
1908     return false;
1909   }
1910   // These are not strictly writeable properties as they cannot be set via -Dprop=val. But that
1911   // is enforced by checking is_internal_module_property(). We need the property to be writeable so
1912   // that multiple occurrences of the associated flag just causes the existing property value to be
1913   // replaced ("last option wins"). Otherwise we would need to keep track of the flags and only convert
1914   // to a property after we have finished flag processing.
1915   bool added = add_property(property, WriteableProperty, internal);
1916   FreeHeap(property);
1917   return added;
1918 }
1919 
1920 bool Arguments::create_numbered_module_property(const char* prop_base_name, const char* prop_value, unsigned int count) {
1921   assert(is_internal_module_property(prop_base_name), "unknown module property: '%s'", prop_base_name);
1922   CDSConfig::check_internal_module_property(prop_base_name, prop_value);
1923   const unsigned int props_count_limit = 1000;
1924   const int max_digits = 3;
1925   const int extra_symbols_count = 3; // includes '.', '=', '\0'
1926 
1927   // Make sure count is < props_count_limit. Otherwise, memory allocation will be too small.
1928   if (count < props_count_limit) {
1929     size_t prop_len = strlen(prop_base_name) + strlen(prop_value) + max_digits + extra_symbols_count;
1930     char* property = AllocateHeap(prop_len, mtArguments);
1931     int ret = jio_snprintf(property, prop_len, "%s.%d=%s", prop_base_name, count, prop_value);
1932     if (ret < 0 || ret >= (int)prop_len) {
1933       FreeHeap(property);
1934       jio_fprintf(defaultStream::error_stream(), "Failed to create property %s.%d=%s\n", prop_base_name, count, prop_value);
1935       return false;
1936     }
1937     bool added = add_property(property, UnwriteableProperty, InternalProperty);
1938     FreeHeap(property);
1939     return added;
1940   }
1941 
1942   jio_fprintf(defaultStream::error_stream(), "Property count limit exceeded: %s, limit=%d\n", prop_base_name, props_count_limit);
1943   return false;
1944 }
1945 
1946 Arguments::ArgsRange Arguments::parse_memory_size(const char* s,
1947                                                   julong* long_arg,
1948                                                   julong min_size,
1949                                                   julong max_size) {
1950   if (!parse_integer(s, long_arg)) return arg_unreadable;
1951   return check_memory_size(*long_arg, min_size, max_size);
1952 }
1953 
1954 jint Arguments::parse_vm_init_args(GrowableArrayCHeap<VMInitArgsGroup, mtArguments>* all_args) {
1955   // Save default settings for some mode flags
1956   Arguments::_AlwaysCompileLoopMethods = AlwaysCompileLoopMethods;
1957   Arguments::_UseOnStackReplacement    = UseOnStackReplacement;
1958   Arguments::_ClipInlining             = ClipInlining;
1959   Arguments::_BackgroundCompilation    = BackgroundCompilation;
1960 
1961   // Remember the default value of SharedBaseAddress.
1962   Arguments::_default_SharedBaseAddress = SharedBaseAddress;
1963 
1964   // Setup flags for mixed which is the default
1965   set_mode_flags(_mixed);
1966 
1967   jint result;
1968   for (int i = 0; i < all_args->length(); i++) {
1969     result = parse_each_vm_init_arg(all_args->at(i)._args, all_args->at(i)._origin);
1970     if (result != JNI_OK) {
1971       return result;
1972     }
1973   }
1974 
1975   // Disable CDS for exploded image
1976   if (!has_jimage()) {
1977     no_shared_spaces("CDS disabled on exploded JDK");
1978   }
1979 
1980   // We need to ensure processor and memory resources have been properly
1981   // configured - which may rely on arguments we just processed - before
1982   // doing the final argument processing. Any argument processing that
1983   // needs to know about processor and memory resources must occur after
1984   // this point.
1985 
1986   os::init_container_support();
1987 
1988   SystemMemoryBarrier::initialize();
1989 
1990   // Do final processing now that all arguments have been parsed
1991   result = finalize_vm_init_args();
1992   if (result != JNI_OK) {
1993     return result;
1994   }
1995 
1996   return JNI_OK;
1997 }
1998 
1999 #if !INCLUDE_JVMTI || INCLUDE_CDS
2000 // Checks if name in command-line argument -agent{lib,path}:name[=options]
2001 // represents a valid JDWP agent.  is_path==true denotes that we
2002 // are dealing with -agentpath (case where name is a path), otherwise with
2003 // -agentlib
2004 static bool valid_jdwp_agent(char *name, bool is_path) {
2005   char *_name;
2006   const char *_jdwp = "jdwp";
2007   size_t _len_jdwp, _len_prefix;
2008 
2009   if (is_path) {
2010     if ((_name = strrchr(name, (int) *os::file_separator())) == nullptr) {
2011       return false;
2012     }
2013 
2014     _name++;  // skip past last path separator
2015     _len_prefix = strlen(JNI_LIB_PREFIX);
2016 
2017     if (strncmp(_name, JNI_LIB_PREFIX, _len_prefix) != 0) {
2018       return false;
2019     }
2020 
2021     _name += _len_prefix;
2022     _len_jdwp = strlen(_jdwp);
2023 
2024     if (strncmp(_name, _jdwp, _len_jdwp) == 0) {
2025       _name += _len_jdwp;
2026     }
2027     else {
2028       return false;
2029     }
2030 
2031     if (strcmp(_name, JNI_LIB_SUFFIX) != 0) {
2032       return false;
2033     }
2034 
2035     return true;
2036   }
2037 
2038   if (strcmp(name, _jdwp) == 0) {
2039     return true;
2040   }
2041 
2042   return false;
2043 }
2044 #endif
2045 
2046 int Arguments::process_patch_mod_option(const char* patch_mod_tail) {
2047   // --patch-module=<module>=<file>(<pathsep><file>)*
2048   assert(patch_mod_tail != nullptr, "Unexpected null patch-module value");
2049   // Find the equal sign between the module name and the path specification
2050   const char* module_equal = strchr(patch_mod_tail, '=');
2051   if (module_equal == nullptr) {
2052     jio_fprintf(defaultStream::output_stream(), "Missing '=' in --patch-module specification\n");
2053     return JNI_ERR;
2054   } else {
2055     // Pick out the module name
2056     size_t module_len = module_equal - patch_mod_tail;
2057     char* module_name = NEW_C_HEAP_ARRAY_RETURN_NULL(char, module_len+1, mtArguments);
2058     if (module_name != nullptr) {
2059       memcpy(module_name, patch_mod_tail, module_len);
2060       *(module_name + module_len) = '\0';
2061       // The path piece begins one past the module_equal sign
2062       add_patch_mod_prefix(module_name, module_equal + 1);
2063       FREE_C_HEAP_ARRAY(char, module_name);
2064       if (!create_numbered_module_property("jdk.module.patch", patch_mod_tail, patch_mod_count++)) {
2065         return JNI_ENOMEM;
2066       }
2067     } else {
2068       return JNI_ENOMEM;
2069     }
2070   }
2071   return JNI_OK;
2072 }
2073 
2074 // Parse -Xss memory string parameter and convert to ThreadStackSize in K.
2075 jint Arguments::parse_xss(const JavaVMOption* option, const char* tail, intx* out_ThreadStackSize) {
2076   // The min and max sizes match the values in globals.hpp, but scaled
2077   // with K. The values have been chosen so that alignment with page
2078   // size doesn't change the max value, which makes the conversions
2079   // back and forth between Xss value and ThreadStackSize value easier.
2080   // The values have also been chosen to fit inside a 32-bit signed type.
2081   const julong min_ThreadStackSize = 0;
2082   const julong max_ThreadStackSize = 1 * M;
2083 
2084   // Make sure the above values match the range set in globals.hpp
2085   const JVMTypedFlagLimit<intx>* limit = JVMFlagLimit::get_range_at(FLAG_MEMBER_ENUM(ThreadStackSize))->cast<intx>();
2086   assert(min_ThreadStackSize == static_cast<julong>(limit->min()), "must be");
2087   assert(max_ThreadStackSize == static_cast<julong>(limit->max()), "must be");
2088 
2089   const julong min_size = min_ThreadStackSize * K;
2090   const julong max_size = max_ThreadStackSize * K;
2091 
2092   assert(is_aligned(max_size, os::vm_page_size()), "Implementation assumption");
2093 
2094   julong size = 0;
2095   ArgsRange errcode = parse_memory_size(tail, &size, min_size, max_size);
2096   if (errcode != arg_in_range) {
2097     bool silent = (option == nullptr); // Allow testing to silence error messages
2098     if (!silent) {
2099       jio_fprintf(defaultStream::error_stream(),
2100                   "Invalid thread stack size: %s\n", option->optionString);
2101       describe_range_error(errcode);
2102     }
2103     return JNI_EINVAL;
2104   }
2105 
2106   // Internally track ThreadStackSize in units of 1024 bytes.
2107   const julong size_aligned = align_up(size, K);
2108   assert(size <= size_aligned,
2109          "Overflow: " JULONG_FORMAT " " JULONG_FORMAT,
2110          size, size_aligned);
2111 
2112   const julong size_in_K = size_aligned / K;
2113   assert(size_in_K < (julong)max_intx,
2114          "size_in_K doesn't fit in the type of ThreadStackSize: " JULONG_FORMAT,
2115          size_in_K);
2116 
2117   // Check that code expanding ThreadStackSize to a page aligned number of bytes won't overflow.
2118   const julong max_expanded = align_up(size_in_K * K, os::vm_page_size());
2119   assert(max_expanded < max_uintx && max_expanded >= size_in_K,
2120          "Expansion overflowed: " JULONG_FORMAT " " JULONG_FORMAT,
2121          max_expanded, size_in_K);
2122 
2123   *out_ThreadStackSize = (intx)size_in_K;
2124 
2125   return JNI_OK;
2126 }
2127 
2128 jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args, JVMFlagOrigin origin) {
2129   // For match_option to return remaining or value part of option string
2130   const char* tail;
2131 
2132   // iterate over arguments
2133   for (int index = 0; index < args->nOptions; index++) {
2134     bool is_absolute_path = false;  // for -agentpath vs -agentlib
2135 
2136     const JavaVMOption* option = args->options + index;
2137 
2138     if (!match_option(option, "-Djava.class.path", &tail) &&
2139         !match_option(option, "-Dsun.java.command", &tail) &&
2140         !match_option(option, "-Dsun.java.launcher", &tail)) {
2141 
2142         // add all jvm options to the jvm_args string. This string
2143         // is used later to set the java.vm.args PerfData string constant.
2144         // the -Djava.class.path and the -Dsun.java.command options are
2145         // omitted from jvm_args string as each have their own PerfData
2146         // string constant object.
2147         build_jvm_args(option->optionString);
2148     }
2149 
2150     // -verbose:[class/module/gc/jni]
2151     if (match_option(option, "-verbose", &tail)) {
2152       if (!strcmp(tail, ":class") || !strcmp(tail, "")) {
2153         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(class, load));
2154         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(class, unload));
2155       } else if (!strcmp(tail, ":module")) {
2156         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(module, load));
2157         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(module, unload));
2158       } else if (!strcmp(tail, ":gc")) {
2159         if (_legacyGCLogging.lastFlag == 0) {
2160           _legacyGCLogging.lastFlag = 1;
2161         }
2162       } else if (!strcmp(tail, ":jni")) {
2163         LogConfiguration::configure_stdout(LogLevel::Debug, true, LOG_TAGS(jni, resolve));
2164       }
2165     // -da / -ea / -disableassertions / -enableassertions
2166     // These accept an optional class/package name separated by a colon, e.g.,
2167     // -da:java.lang.Thread.
2168     } else if (match_option(option, user_assertion_options, &tail, true)) {
2169       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2170       if (*tail == '\0') {
2171         JavaAssertions::setUserClassDefault(enable);
2172       } else {
2173         assert(*tail == ':', "bogus match by match_option()");
2174         JavaAssertions::addOption(tail + 1, enable);
2175       }
2176     // -dsa / -esa / -disablesystemassertions / -enablesystemassertions
2177     } else if (match_option(option, system_assertion_options, &tail, false)) {
2178       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2179       JavaAssertions::setSystemClassDefault(enable);
2180     // -bootclasspath:
2181     } else if (match_option(option, "-Xbootclasspath:", &tail)) {
2182         jio_fprintf(defaultStream::output_stream(),
2183           "-Xbootclasspath is no longer a supported option.\n");
2184         return JNI_EINVAL;
2185     // -bootclasspath/a:
2186     } else if (match_option(option, "-Xbootclasspath/a:", &tail)) {
2187       Arguments::append_sysclasspath(tail);
2188     // -bootclasspath/p:
2189     } else if (match_option(option, "-Xbootclasspath/p:", &tail)) {
2190         jio_fprintf(defaultStream::output_stream(),
2191           "-Xbootclasspath/p is no longer a supported option.\n");
2192         return JNI_EINVAL;
2193     // -Xrun
2194     } else if (match_option(option, "-Xrun", &tail)) {
2195       if (tail != nullptr) {
2196         const char* pos = strchr(tail, ':');
2197         size_t len = (pos == nullptr) ? strlen(tail) : pos - tail;
2198         char* name = NEW_C_HEAP_ARRAY(char, len + 1, mtArguments);
2199         jio_snprintf(name, len + 1, "%s", tail);
2200 
2201         char *options = nullptr;
2202         if(pos != nullptr) {
2203           size_t len2 = strlen(pos+1) + 1; // options start after ':'.  Final zero must be copied.
2204           options = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len2, mtArguments), pos+1, len2);
2205         }
2206 #if !INCLUDE_JVMTI
2207         if (strcmp(name, "jdwp") == 0) {
2208           jio_fprintf(defaultStream::error_stream(),
2209             "Debugging agents are not supported in this VM\n");
2210           return JNI_ERR;
2211         }
2212 #endif // !INCLUDE_JVMTI
2213         JvmtiAgentList::add_xrun(name, options, false);
2214         FREE_C_HEAP_ARRAY(char, name);
2215         FREE_C_HEAP_ARRAY(char, options);
2216       }
2217     } else if (match_option(option, "--add-reads=", &tail)) {
2218       if (!create_numbered_module_property("jdk.module.addreads", tail, addreads_count++)) {
2219         return JNI_ENOMEM;
2220       }
2221     } else if (match_option(option, "--add-exports=", &tail)) {
2222       if (!create_numbered_module_property("jdk.module.addexports", tail, addexports_count++)) {
2223         return JNI_ENOMEM;
2224       }
2225     } else if (match_option(option, "--add-opens=", &tail)) {
2226       if (!create_numbered_module_property("jdk.module.addopens", tail, addopens_count++)) {
2227         return JNI_ENOMEM;
2228       }
2229     } else if (match_option(option, "--add-modules=", &tail)) {
2230       if (!create_numbered_module_property("jdk.module.addmods", tail, _addmods_count++)) {
2231         return JNI_ENOMEM;
2232       }
2233 #if INCLUDE_JVMCI
2234       if (!_jvmci_module_added) {
2235         const char *jvmci_module = strstr(tail, "jdk.internal.vm.ci");
2236         if (jvmci_module != nullptr) {
2237           char before = *(jvmci_module - 1);
2238           char after  = *(jvmci_module + strlen("jdk.internal.vm.ci"));
2239           if ((before == '=' || before == ',') && (after == '\0' || after == ',')) {
2240             FLAG_SET_DEFAULT(EnableJVMCI, true);
2241             _jvmci_module_added = true;
2242           }
2243         }
2244       }
2245 #endif
2246     } else if (match_option(option, "--enable-native-access=", &tail)) {
2247       if (!create_numbered_module_property("jdk.module.enable.native.access", tail, enable_native_access_count++)) {
2248         return JNI_ENOMEM;
2249       }
2250     } else if (match_option(option, "--illegal-native-access=", &tail)) {
2251       if (!create_module_property("jdk.module.illegal.native.access", tail, InternalProperty)) {
2252         return JNI_ENOMEM;
2253       }
2254     } else if (match_option(option, "--limit-modules=", &tail)) {
2255       if (!create_module_property("jdk.module.limitmods", tail, InternalProperty)) {
2256         return JNI_ENOMEM;
2257       }
2258     } else if (match_option(option, "--module-path=", &tail)) {
2259       if (!create_module_property("jdk.module.path", tail, ExternalProperty)) {
2260         return JNI_ENOMEM;
2261       }
2262     } else if (match_option(option, "--upgrade-module-path=", &tail)) {
2263       if (!create_module_property("jdk.module.upgrade.path", tail, ExternalProperty)) {
2264         return JNI_ENOMEM;
2265       }
2266     } else if (match_option(option, "--patch-module=", &tail)) {
2267       // --patch-module=<module>=<file>(<pathsep><file>)*
2268       int res = process_patch_mod_option(tail);
2269       if (res != JNI_OK) {
2270         return res;
2271       }
2272     } else if (match_option(option, "--enable-final-field-mutation=", &tail)) {
2273       if (!create_numbered_module_property("jdk.module.enable.final.field.mutation", tail, enable_final_field_mutation++)) {
2274         return JNI_ENOMEM;
2275       }
2276     } else if (match_option(option, "--illegal-final-field-mutation=", &tail)) {
2277       if (strcmp(tail, "allow") == 0 || strcmp(tail, "warn") == 0 || strcmp(tail, "debug") == 0 || strcmp(tail, "deny") == 0) {
2278         PropertyList_unique_add(&_system_properties, "jdk.module.illegal.final.field.mutation", tail,
2279                                 AddProperty, WriteableProperty, InternalProperty);
2280       } else {
2281         jio_fprintf(defaultStream::error_stream(),
2282                     "Value specified to --illegal-final-field-mutation not recognized: '%s'\n", tail);
2283         return JNI_ERR;
2284       }
2285     } else if (match_option(option, "--sun-misc-unsafe-memory-access=", &tail)) {
2286       if (strcmp(tail, "allow") == 0 || strcmp(tail, "warn") == 0 || strcmp(tail, "debug") == 0 || strcmp(tail, "deny") == 0) {
2287         PropertyList_unique_add(&_system_properties, "sun.misc.unsafe.memory.access", tail,
2288                                 AddProperty, WriteableProperty, InternalProperty);
2289       } else {
2290         jio_fprintf(defaultStream::error_stream(),
2291                     "Value specified to --sun-misc-unsafe-memory-access not recognized: '%s'\n", tail);
2292         return JNI_ERR;
2293       }
2294     } else if (match_option(option, "--illegal-access=", &tail)) {
2295       char version[256];
2296       JDK_Version::jdk(17).to_string(version, sizeof(version));
2297       warning("Ignoring option %s; support was removed in %s", option->optionString, version);
2298     // -agentlib and -agentpath
2299     } else if (match_option(option, "-agentlib:", &tail) ||
2300           (is_absolute_path = match_option(option, "-agentpath:", &tail))) {
2301       if(tail != nullptr) {
2302         const char* pos = strchr(tail, '=');
2303         char* name;
2304         if (pos == nullptr) {
2305           name = os::strdup_check_oom(tail, mtArguments);
2306         } else {
2307           size_t len = pos - tail;
2308           name = NEW_C_HEAP_ARRAY(char, len + 1, mtArguments);
2309           memcpy(name, tail, len);
2310           name[len] = '\0';
2311         }
2312 
2313         char *options = nullptr;
2314         if(pos != nullptr) {
2315           options = os::strdup_check_oom(pos + 1, mtArguments);
2316         }
2317 #if !INCLUDE_JVMTI
2318         if (valid_jdwp_agent(name, is_absolute_path)) {
2319           jio_fprintf(defaultStream::error_stream(),
2320             "Debugging agents are not supported in this VM\n");
2321           return JNI_ERR;
2322         }
2323 #elif INCLUDE_CDS
2324         if (valid_jdwp_agent(name, is_absolute_path)) {
2325           _has_jdwp_agent = true;
2326         }
2327 #endif // !INCLUDE_JVMTI
2328         JvmtiAgentList::add(name, options, is_absolute_path);
2329         os::free(name);
2330         os::free(options);
2331       }
2332     // -javaagent
2333     } else if (match_option(option, "-javaagent:", &tail)) {
2334 #if !INCLUDE_JVMTI
2335       jio_fprintf(defaultStream::error_stream(),
2336         "Instrumentation agents are not supported in this VM\n");
2337       return JNI_ERR;
2338 #else
2339       if (tail != nullptr) {
2340         size_t length = strlen(tail) + 1;
2341         char *options = NEW_C_HEAP_ARRAY(char, length, mtArguments);
2342         jio_snprintf(options, length, "%s", tail);
2343         JvmtiAgentList::add("instrument", options, false);
2344         FREE_C_HEAP_ARRAY(char, options);
2345 
2346         // java agents need module java.instrument
2347         if (!create_numbered_module_property("jdk.module.addmods", "java.instrument", _addmods_count++)) {
2348           return JNI_ENOMEM;
2349         }
2350       }
2351 #endif // !INCLUDE_JVMTI
2352     // --enable_preview
2353     } else if (match_option(option, "--enable-preview")) {
2354       set_enable_preview();
2355     // -Xnoclassgc
2356     } else if (match_option(option, "-Xnoclassgc")) {
2357       if (FLAG_SET_CMDLINE(ClassUnloading, false) != JVMFlag::SUCCESS) {
2358         return JNI_EINVAL;
2359       }
2360     // -Xbatch
2361     } else if (match_option(option, "-Xbatch")) {
2362       if (FLAG_SET_CMDLINE(BackgroundCompilation, false) != JVMFlag::SUCCESS) {
2363         return JNI_EINVAL;
2364       }
2365     // -Xmn for compatibility with other JVM vendors
2366     } else if (match_option(option, "-Xmn", &tail)) {
2367       julong long_initial_young_size = 0;
2368       ArgsRange errcode = parse_memory_size(tail, &long_initial_young_size, 1);
2369       if (errcode != arg_in_range) {
2370         jio_fprintf(defaultStream::error_stream(),
2371                     "Invalid initial young generation size: %s\n", option->optionString);
2372         describe_range_error(errcode);
2373         return JNI_EINVAL;
2374       }
2375       if (FLAG_SET_CMDLINE(MaxNewSize, (size_t)long_initial_young_size) != JVMFlag::SUCCESS) {
2376         return JNI_EINVAL;
2377       }
2378       if (FLAG_SET_CMDLINE(NewSize, (size_t)long_initial_young_size) != JVMFlag::SUCCESS) {
2379         return JNI_EINVAL;
2380       }
2381     // -Xms
2382     } else if (match_option(option, "-Xms", &tail)) {
2383       julong size = 0;
2384       // an initial heap size of 0 means automatically determine
2385       ArgsRange errcode = parse_memory_size(tail, &size, 0);
2386       if (errcode != arg_in_range) {
2387         jio_fprintf(defaultStream::error_stream(),
2388                     "Invalid initial heap size: %s\n", option->optionString);
2389         describe_range_error(errcode);
2390         return JNI_EINVAL;
2391       }
2392       if (FLAG_SET_CMDLINE(MinHeapSize, (size_t)size) != JVMFlag::SUCCESS) {
2393         return JNI_EINVAL;
2394       }
2395       if (FLAG_SET_CMDLINE(InitialHeapSize, (size_t)size) != JVMFlag::SUCCESS) {
2396         return JNI_EINVAL;
2397       }
2398     // -Xmx
2399     } else if (match_option(option, "-Xmx", &tail) || match_option(option, "-XX:MaxHeapSize=", &tail)) {
2400       julong long_max_heap_size = 0;
2401       ArgsRange errcode = parse_memory_size(tail, &long_max_heap_size, 1);
2402       if (errcode != arg_in_range) {
2403         jio_fprintf(defaultStream::error_stream(),
2404                     "Invalid maximum heap size: %s\n", option->optionString);
2405         describe_range_error(errcode);
2406         return JNI_EINVAL;
2407       }
2408       if (FLAG_SET_CMDLINE(MaxHeapSize, (size_t)long_max_heap_size) != JVMFlag::SUCCESS) {
2409         return JNI_EINVAL;
2410       }
2411     // Xmaxf
2412     } else if (match_option(option, "-Xmaxf", &tail)) {
2413       char* err;
2414       double dmaxf = strtod(tail, &err);
2415       if (*err != '\0' || *tail == '\0') {
2416         jio_fprintf(defaultStream::error_stream(),
2417                     "Bad max heap free ratio: %s\n",
2418                     option->optionString);
2419         return JNI_EINVAL;
2420       }
2421       if (dmaxf < 0.0 || dmaxf > 1.0) {
2422         jio_fprintf(defaultStream::error_stream(),
2423                     "-Xmaxf value (%s) is outside the allowed range [ 0.0 ... 1.0 ]\n",
2424                     option->optionString);
2425         return JNI_EINVAL;
2426       }
2427       const uintx umaxf = (uintx)(dmaxf * 100);
2428       if (MinHeapFreeRatio > umaxf) {
2429         jio_fprintf(defaultStream::error_stream(),
2430                     "-Xmaxf value (%s) must be greater than or equal to the implicit -Xminf value (%.2f)\n",
2431                     tail, MinHeapFreeRatio / 100.0f);
2432         return JNI_EINVAL;
2433       }
2434       if (FLAG_SET_CMDLINE(MaxHeapFreeRatio, umaxf) != JVMFlag::SUCCESS) {
2435         return JNI_EINVAL;
2436       }
2437     // Xminf
2438     } else if (match_option(option, "-Xminf", &tail)) {
2439       char* err;
2440       double dminf = strtod(tail, &err);
2441       if (*err != '\0' || *tail == '\0') {
2442         jio_fprintf(defaultStream::error_stream(),
2443                     "Bad min heap free ratio: %s\n",
2444                     option->optionString);
2445         return JNI_EINVAL;
2446       }
2447       if (dminf < 0.0 || dminf > 1.0) {
2448         jio_fprintf(defaultStream::error_stream(),
2449                     "-Xminf value (%s) is outside the allowed range [ 0.0 ... 1.0 ]\n",
2450                     tail);
2451         return JNI_EINVAL;
2452       }
2453       const uintx uminf = (uintx)(dminf * 100);
2454       if (MaxHeapFreeRatio < uminf) {
2455         jio_fprintf(defaultStream::error_stream(),
2456                     "-Xminf value (%s) must be less than or equal to the implicit -Xmaxf value (%.2f)\n",
2457                     tail, MaxHeapFreeRatio / 100.0f);
2458         return JNI_EINVAL;
2459       }
2460       if (FLAG_SET_CMDLINE(MinHeapFreeRatio, uminf) != JVMFlag::SUCCESS) {
2461         return JNI_EINVAL;
2462       }
2463     // -Xss
2464     } else if (match_option(option, "-Xss", &tail)) {
2465       intx value = 0;
2466       jint err = parse_xss(option, tail, &value);
2467       if (err != JNI_OK) {
2468         return err;
2469       }
2470       if (FLAG_SET_CMDLINE(ThreadStackSize, value) != JVMFlag::SUCCESS) {
2471         return JNI_EINVAL;
2472       }
2473     } else if (match_option(option, "-Xmaxjitcodesize", &tail) ||
2474                match_option(option, "-XX:ReservedCodeCacheSize=", &tail)) {
2475       if (match_option(option, "-Xmaxjitcodesize", &tail)) {
2476         warning("Option -Xmaxjitcodesize was deprecated in JDK 26 and will likely be removed in a future release.");
2477       }
2478       julong long_ReservedCodeCacheSize = 0;
2479 
2480       ArgsRange errcode = parse_memory_size(tail, &long_ReservedCodeCacheSize, 1);
2481       if (errcode != arg_in_range) {
2482         jio_fprintf(defaultStream::error_stream(),
2483                     "Invalid maximum code cache size: %s.\n", option->optionString);
2484         return JNI_EINVAL;
2485       }
2486       if (FLAG_SET_CMDLINE(ReservedCodeCacheSize, (size_t)long_ReservedCodeCacheSize) != JVMFlag::SUCCESS) {
2487         return JNI_EINVAL;
2488       }
2489     // -green
2490     } else if (match_option(option, "-green")) {
2491       jio_fprintf(defaultStream::error_stream(),
2492                   "Green threads support not available\n");
2493           return JNI_EINVAL;
2494     // -native
2495     } else if (match_option(option, "-native")) {
2496           // HotSpot always uses native threads, ignore silently for compatibility
2497     // -Xrs
2498     } else if (match_option(option, "-Xrs")) {
2499           // Classic/EVM option, new functionality
2500       if (FLAG_SET_CMDLINE(ReduceSignalUsage, true) != JVMFlag::SUCCESS) {
2501         return JNI_EINVAL;
2502       }
2503       // -Xprof
2504     } else if (match_option(option, "-Xprof")) {
2505       char version[256];
2506       // Obsolete in JDK 10
2507       JDK_Version::jdk(10).to_string(version, sizeof(version));
2508       warning("Ignoring option %s; support was removed in %s", option->optionString, version);
2509     // -Xinternalversion
2510     } else if (match_option(option, "-Xinternalversion")) {
2511       jio_fprintf(defaultStream::output_stream(), "%s\n",
2512                   VM_Version::internal_vm_info_string());
2513       vm_exit(0);
2514 #ifndef PRODUCT
2515     // -Xprintflags
2516     } else if (match_option(option, "-Xprintflags")) {
2517       JVMFlag::printFlags(tty, false);
2518       vm_exit(0);
2519 #endif
2520     // -D
2521     } else if (match_option(option, "-D", &tail)) {
2522       const char* value;
2523       if (match_option(option, "-Djava.endorsed.dirs=", &value) &&
2524             *value!= '\0' && strcmp(value, "\"\"") != 0) {
2525         // abort if -Djava.endorsed.dirs is set
2526         jio_fprintf(defaultStream::output_stream(),
2527           "-Djava.endorsed.dirs=%s is not supported. Endorsed standards and standalone APIs\n"
2528           "in modular form will be supported via the concept of upgradeable modules.\n", value);
2529         return JNI_EINVAL;
2530       }
2531       if (match_option(option, "-Djava.ext.dirs=", &value) &&
2532             *value != '\0' && strcmp(value, "\"\"") != 0) {
2533         // abort if -Djava.ext.dirs is set
2534         jio_fprintf(defaultStream::output_stream(),
2535           "-Djava.ext.dirs=%s is not supported.  Use -classpath instead.\n", value);
2536         return JNI_EINVAL;
2537       }
2538       // Check for module related properties.  They must be set using the modules
2539       // options. For example: use "--add-modules=java.sql", not
2540       // "-Djdk.module.addmods=java.sql"
2541       if (is_internal_module_property(option->optionString + 2)) {
2542         needs_module_property_warning = true;
2543         continue;
2544       }
2545       if (!add_property(tail)) {
2546         return JNI_ENOMEM;
2547       }
2548       // Out of the box management support
2549       if (match_option(option, "-Dcom.sun.management", &tail)) {
2550 #if INCLUDE_MANAGEMENT
2551         if (FLAG_SET_CMDLINE(ManagementServer, true) != JVMFlag::SUCCESS) {
2552           return JNI_EINVAL;
2553         }
2554         // management agent in module jdk.management.agent
2555         if (!create_numbered_module_property("jdk.module.addmods", "jdk.management.agent", _addmods_count++)) {
2556           return JNI_ENOMEM;
2557         }
2558 #else
2559         jio_fprintf(defaultStream::output_stream(),
2560           "-Dcom.sun.management is not supported in this VM.\n");
2561         return JNI_ERR;
2562 #endif
2563       }
2564     // -Xint
2565     } else if (match_option(option, "-Xint")) {
2566           set_mode_flags(_int);
2567           mode_flag_cmd_line = true;
2568     // -Xmixed
2569     } else if (match_option(option, "-Xmixed")) {
2570           set_mode_flags(_mixed);
2571           mode_flag_cmd_line = true;
2572     // -Xcomp
2573     } else if (match_option(option, "-Xcomp")) {
2574       // for testing the compiler; turn off all flags that inhibit compilation
2575           set_mode_flags(_comp);
2576           mode_flag_cmd_line = true;
2577     // -Xshare:dump
2578     } else if (match_option(option, "-Xshare:dump")) {
2579       CDSConfig::enable_dumping_static_archive();
2580       CDSConfig::set_old_cds_flags_used();
2581     // -Xshare:on
2582     } else if (match_option(option, "-Xshare:on")) {
2583       UseSharedSpaces = true;
2584       RequireSharedSpaces = true;
2585       CDSConfig::set_old_cds_flags_used();
2586     // -Xshare:auto || -XX:ArchiveClassesAtExit=<archive file>
2587     } else if (match_option(option, "-Xshare:auto")) {
2588       UseSharedSpaces = true;
2589       RequireSharedSpaces = false;
2590       xshare_auto_cmd_line = true;
2591       CDSConfig::set_old_cds_flags_used();
2592     // -Xshare:off
2593     } else if (match_option(option, "-Xshare:off")) {
2594       UseSharedSpaces = false;
2595       RequireSharedSpaces = false;
2596       CDSConfig::set_old_cds_flags_used();
2597     // -Xverify
2598     } else if (match_option(option, "-Xverify", &tail)) {
2599       if (strcmp(tail, ":all") == 0 || strcmp(tail, "") == 0) {
2600         if (FLAG_SET_CMDLINE(BytecodeVerificationLocal, true) != JVMFlag::SUCCESS) {
2601           return JNI_EINVAL;
2602         }
2603         if (FLAG_SET_CMDLINE(BytecodeVerificationRemote, true) != JVMFlag::SUCCESS) {
2604           return JNI_EINVAL;
2605         }
2606       } else if (strcmp(tail, ":remote") == 0) {
2607         if (FLAG_SET_CMDLINE(BytecodeVerificationLocal, false) != JVMFlag::SUCCESS) {
2608           return JNI_EINVAL;
2609         }
2610         if (FLAG_SET_CMDLINE(BytecodeVerificationRemote, true) != JVMFlag::SUCCESS) {
2611           return JNI_EINVAL;
2612         }
2613       } else if (strcmp(tail, ":none") == 0) {
2614         if (FLAG_SET_CMDLINE(BytecodeVerificationLocal, false) != JVMFlag::SUCCESS) {
2615           return JNI_EINVAL;
2616         }
2617         if (FLAG_SET_CMDLINE(BytecodeVerificationRemote, false) != JVMFlag::SUCCESS) {
2618           return JNI_EINVAL;
2619         }
2620         warning("Options -Xverify:none and -noverify were deprecated in JDK 13 and will likely be removed in a future release.");
2621       } else if (is_bad_option(option, args->ignoreUnrecognized, "verification")) {
2622         return JNI_EINVAL;
2623       }
2624     // -Xdebug
2625     } else if (match_option(option, "-Xdebug")) {
2626       warning("Option -Xdebug was deprecated in JDK 22 and will likely be removed in a future release.");
2627     } else if (match_option(option, "-Xloggc:", &tail)) {
2628       // Deprecated flag to redirect GC output to a file. -Xloggc:<filename>
2629       log_warning(gc)("-Xloggc is deprecated. Will use -Xlog:gc:%s instead.", tail);
2630       _legacyGCLogging.lastFlag = 2;
2631       _legacyGCLogging.file = os::strdup_check_oom(tail);
2632     } else if (match_option(option, "-Xlog", &tail)) {
2633       bool ret = false;
2634       if (strcmp(tail, ":help") == 0) {
2635         fileStream stream(defaultStream::output_stream());
2636         LogConfiguration::print_command_line_help(&stream);
2637         vm_exit(0);
2638       } else if (strcmp(tail, ":disable") == 0) {
2639         LogConfiguration::disable_logging();
2640         ret = true;
2641       } else if (strncmp(tail, ":async", strlen(":async")) == 0) {
2642         const char* async_tail = tail + strlen(":async");
2643         ret = LogConfiguration::parse_async_argument(async_tail);
2644       } else if (*tail == '\0') {
2645         ret = LogConfiguration::parse_command_line_arguments();
2646         assert(ret, "-Xlog without arguments should never fail to parse");
2647       } else if (*tail == ':') {
2648         ret = LogConfiguration::parse_command_line_arguments(tail + 1);
2649       }
2650       if (ret == false) {
2651         jio_fprintf(defaultStream::error_stream(),
2652                     "Invalid -Xlog option '-Xlog%s', see error log for details.\n",
2653                     tail);
2654         return JNI_EINVAL;
2655       }
2656     // JNI hooks
2657     } else if (match_option(option, "-Xcheck", &tail)) {
2658       if (!strcmp(tail, ":jni")) {
2659 #if !INCLUDE_JNI_CHECK
2660         warning("JNI CHECKING is not supported in this VM");
2661 #else
2662         CheckJNICalls = true;
2663 #endif // INCLUDE_JNI_CHECK
2664       } else if (is_bad_option(option, args->ignoreUnrecognized,
2665                                      "check")) {
2666         return JNI_EINVAL;
2667       }
2668     } else if (match_option(option, "vfprintf")) {
2669       _vfprintf_hook = CAST_TO_FN_PTR(vfprintf_hook_t, option->extraInfo);
2670     } else if (match_option(option, "exit")) {
2671       _exit_hook = CAST_TO_FN_PTR(exit_hook_t, option->extraInfo);
2672     } else if (match_option(option, "abort")) {
2673       _abort_hook = CAST_TO_FN_PTR(abort_hook_t, option->extraInfo);
2674     // Need to keep consistency of MaxTenuringThreshold and AlwaysTenure/NeverTenure;
2675     // and the last option wins.
2676     } else if (match_option(option, "-XX:+NeverTenure")) {
2677       if (FLAG_SET_CMDLINE(NeverTenure, true) != JVMFlag::SUCCESS) {
2678         return JNI_EINVAL;
2679       }
2680       if (FLAG_SET_CMDLINE(AlwaysTenure, false) != JVMFlag::SUCCESS) {
2681         return JNI_EINVAL;
2682       }
2683       if (FLAG_SET_CMDLINE(MaxTenuringThreshold, markWord::max_age + 1) != JVMFlag::SUCCESS) {
2684         return JNI_EINVAL;
2685       }
2686     } else if (match_option(option, "-XX:+AlwaysTenure")) {
2687       if (FLAG_SET_CMDLINE(NeverTenure, false) != JVMFlag::SUCCESS) {
2688         return JNI_EINVAL;
2689       }
2690       if (FLAG_SET_CMDLINE(AlwaysTenure, true) != JVMFlag::SUCCESS) {
2691         return JNI_EINVAL;
2692       }
2693       if (FLAG_SET_CMDLINE(MaxTenuringThreshold, 0) != JVMFlag::SUCCESS) {
2694         return JNI_EINVAL;
2695       }
2696     } else if (match_option(option, "-XX:MaxTenuringThreshold=", &tail)) {
2697       uint max_tenuring_thresh = 0;
2698       if (!parse_uint(tail, &max_tenuring_thresh, 0)) {
2699         jio_fprintf(defaultStream::error_stream(),
2700                     "Improperly specified VM option \'MaxTenuringThreshold=%s\'\n", tail);
2701         return JNI_EINVAL;
2702       }
2703 
2704       if (FLAG_SET_CMDLINE(MaxTenuringThreshold, max_tenuring_thresh) != JVMFlag::SUCCESS) {
2705         return JNI_EINVAL;
2706       }
2707 
2708       if (MaxTenuringThreshold == 0) {
2709         if (FLAG_SET_CMDLINE(NeverTenure, false) != JVMFlag::SUCCESS) {
2710           return JNI_EINVAL;
2711         }
2712         if (FLAG_SET_CMDLINE(AlwaysTenure, true) != JVMFlag::SUCCESS) {
2713           return JNI_EINVAL;
2714         }
2715       } else {
2716         if (FLAG_SET_CMDLINE(NeverTenure, false) != JVMFlag::SUCCESS) {
2717           return JNI_EINVAL;
2718         }
2719         if (FLAG_SET_CMDLINE(AlwaysTenure, false) != JVMFlag::SUCCESS) {
2720           return JNI_EINVAL;
2721         }
2722       }
2723     } else if (match_option(option, "-XX:+DisplayVMOutputToStderr")) {
2724       if (FLAG_SET_CMDLINE(DisplayVMOutputToStdout, false) != JVMFlag::SUCCESS) {
2725         return JNI_EINVAL;
2726       }
2727       if (FLAG_SET_CMDLINE(DisplayVMOutputToStderr, true) != JVMFlag::SUCCESS) {
2728         return JNI_EINVAL;
2729       }
2730     } else if (match_option(option, "-XX:+DisplayVMOutputToStdout")) {
2731       if (FLAG_SET_CMDLINE(DisplayVMOutputToStderr, false) != JVMFlag::SUCCESS) {
2732         return JNI_EINVAL;
2733       }
2734       if (FLAG_SET_CMDLINE(DisplayVMOutputToStdout, true) != JVMFlag::SUCCESS) {
2735         return JNI_EINVAL;
2736       }
2737     } else if (match_option(option, "-XX:+ErrorFileToStderr")) {
2738       if (FLAG_SET_CMDLINE(ErrorFileToStdout, false) != JVMFlag::SUCCESS) {
2739         return JNI_EINVAL;
2740       }
2741       if (FLAG_SET_CMDLINE(ErrorFileToStderr, true) != JVMFlag::SUCCESS) {
2742         return JNI_EINVAL;
2743       }
2744     } else if (match_option(option, "-XX:+ErrorFileToStdout")) {
2745       if (FLAG_SET_CMDLINE(ErrorFileToStderr, false) != JVMFlag::SUCCESS) {
2746         return JNI_EINVAL;
2747       }
2748       if (FLAG_SET_CMDLINE(ErrorFileToStdout, true) != JVMFlag::SUCCESS) {
2749         return JNI_EINVAL;
2750       }
2751     } else if (match_option(option, "--finalization=", &tail)) {
2752       if (strcmp(tail, "enabled") == 0) {
2753         InstanceKlass::set_finalization_enabled(true);
2754       } else if (strcmp(tail, "disabled") == 0) {
2755         InstanceKlass::set_finalization_enabled(false);
2756       } else {
2757         jio_fprintf(defaultStream::error_stream(),
2758                     "Invalid finalization value '%s', must be 'disabled' or 'enabled'.\n",
2759                     tail);
2760         return JNI_EINVAL;
2761       }
2762 #if !defined(DTRACE_ENABLED)
2763     } else if (match_option(option, "-XX:+DTraceMethodProbes")) {
2764       jio_fprintf(defaultStream::error_stream(),
2765                   "DTraceMethodProbes flag is not applicable for this configuration\n");
2766       return JNI_EINVAL;
2767     } else if (match_option(option, "-XX:+DTraceAllocProbes")) {
2768       jio_fprintf(defaultStream::error_stream(),
2769                   "DTraceAllocProbes flag is not applicable for this configuration\n");
2770       return JNI_EINVAL;
2771     } else if (match_option(option, "-XX:+DTraceMonitorProbes")) {
2772       jio_fprintf(defaultStream::error_stream(),
2773                   "DTraceMonitorProbes flag is not applicable for this configuration\n");
2774       return JNI_EINVAL;
2775 #endif // !defined(DTRACE_ENABLED)
2776 #ifdef ASSERT
2777     } else if (match_option(option, "-XX:+FullGCALot")) {
2778       if (FLAG_SET_CMDLINE(FullGCALot, true) != JVMFlag::SUCCESS) {
2779         return JNI_EINVAL;
2780       }
2781 #endif
2782 #if !INCLUDE_MANAGEMENT
2783     } else if (match_option(option, "-XX:+ManagementServer")) {
2784         jio_fprintf(defaultStream::error_stream(),
2785           "ManagementServer is not supported in this VM.\n");
2786         return JNI_ERR;
2787 #endif // INCLUDE_MANAGEMENT
2788 #if INCLUDE_JVMCI
2789     } else if (match_option(option, "-XX:-EnableJVMCIProduct") || match_option(option, "-XX:-UseGraalJIT")) {
2790       if (EnableJVMCIProduct) {
2791         jio_fprintf(defaultStream::error_stream(),
2792                   "-XX:-EnableJVMCIProduct or -XX:-UseGraalJIT cannot come after -XX:+EnableJVMCIProduct or -XX:+UseGraalJIT\n");
2793         return JNI_EINVAL;
2794       }
2795     } else if (match_option(option, "-XX:+EnableJVMCIProduct") || match_option(option, "-XX:+UseGraalJIT")) {
2796       bool use_graal_jit = match_option(option, "-XX:+UseGraalJIT");
2797       if (use_graal_jit) {
2798         const char* jvmci_compiler = get_property("jvmci.Compiler");
2799         if (jvmci_compiler != nullptr) {
2800           if (strncmp(jvmci_compiler, "graal", strlen("graal")) != 0) {
2801             jio_fprintf(defaultStream::error_stream(),
2802               "Value of jvmci.Compiler incompatible with +UseGraalJIT: %s\n", jvmci_compiler);
2803             return JNI_ERR;
2804           }
2805         } else if (!add_property("jvmci.Compiler=graal")) {
2806             return JNI_ENOMEM;
2807         }
2808       }
2809 
2810       // Just continue, since "-XX:+EnableJVMCIProduct" or "-XX:+UseGraalJIT" has been specified before
2811       if (EnableJVMCIProduct) {
2812         continue;
2813       }
2814       JVMFlag *jvmciFlag = JVMFlag::find_flag("EnableJVMCIProduct");
2815       // Allow this flag if it has been unlocked.
2816       if (jvmciFlag != nullptr && jvmciFlag->is_unlocked()) {
2817         if (!JVMCIGlobals::enable_jvmci_product_mode(origin, use_graal_jit)) {
2818           jio_fprintf(defaultStream::error_stream(),
2819             "Unable to enable JVMCI in product mode\n");
2820           return JNI_ERR;
2821         }
2822       }
2823       // The flag was locked so process normally to report that error
2824       else if (!process_argument(use_graal_jit ? "UseGraalJIT" : "EnableJVMCIProduct", args->ignoreUnrecognized, origin)) {
2825         return JNI_EINVAL;
2826       }
2827 #endif // INCLUDE_JVMCI
2828 #if INCLUDE_JFR
2829     } else if (match_jfr_option(&option)) {
2830       return JNI_EINVAL;
2831 #endif
2832     } else if (match_option(option, "-XX:", &tail)) { // -XX:xxxx
2833       // Skip -XX:Flags= and -XX:VMOptionsFile= since those cases have
2834       // already been handled
2835       if ((strncmp(tail, "Flags=", strlen("Flags=")) != 0) &&
2836           (strncmp(tail, "VMOptionsFile=", strlen("VMOptionsFile=")) != 0)) {
2837         if (!process_argument(tail, args->ignoreUnrecognized, origin)) {
2838           return JNI_EINVAL;
2839         }
2840       }
2841     // Unknown option
2842     } else if (is_bad_option(option, args->ignoreUnrecognized)) {
2843       return JNI_ERR;
2844     }
2845   }
2846 
2847   // PrintSharedArchiveAndExit will turn on
2848   //   -Xshare:on
2849   //   -Xlog:class+path=info
2850   if (PrintSharedArchiveAndExit) {
2851     UseSharedSpaces = true;
2852     RequireSharedSpaces = true;
2853     LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(class, path));
2854   }
2855 
2856   fix_appclasspath();
2857 
2858   return JNI_OK;
2859 }
2860 
2861 void Arguments::set_ext_dirs(char *value) {
2862   _ext_dirs = os::strdup_check_oom(value);
2863 }
2864 
2865 void Arguments::add_patch_mod_prefix(const char* module_name, const char* path) {
2866   // For java.base check for duplicate --patch-module options being specified on the command line.
2867   // This check is only required for java.base, all other duplicate module specifications
2868   // will be checked during module system initialization.  The module system initialization
2869   // will throw an ExceptionInInitializerError if this situation occurs.
2870   if (strcmp(module_name, JAVA_BASE_NAME) == 0) {
2871     if (patch_mod_javabase) {
2872       vm_exit_during_initialization("Cannot specify " JAVA_BASE_NAME " more than once to --patch-module");
2873     } else {
2874       patch_mod_javabase = true;
2875     }
2876   }
2877 
2878   // Create GrowableArray lazily, only if --patch-module has been specified
2879   if (_patch_mod_prefix == nullptr) {
2880     _patch_mod_prefix = new (mtArguments) GrowableArray<ModulePatchPath*>(10, mtArguments);
2881   }
2882 
2883   _patch_mod_prefix->push(new ModulePatchPath(module_name, path));
2884 }
2885 
2886 // Remove all empty paths from the app classpath (if IgnoreEmptyClassPaths is enabled)
2887 //
2888 // This is necessary because some apps like to specify classpath like -cp foo.jar:${XYZ}:bar.jar
2889 // in their start-up scripts. If XYZ is empty, the classpath will look like "-cp foo.jar::bar.jar".
2890 // Java treats such empty paths as if the user specified "-cp foo.jar:.:bar.jar". I.e., an empty
2891 // path is treated as the current directory.
2892 //
2893 // This causes problems with CDS, which requires that all directories specified in the classpath
2894 // must be empty. In most cases, applications do NOT want to load classes from the current
2895 // directory anyway. Adding -XX:+IgnoreEmptyClassPaths will make these applications' start-up
2896 // scripts compatible with CDS.
2897 void Arguments::fix_appclasspath() {
2898   if (IgnoreEmptyClassPaths) {
2899     const char separator = *os::path_separator();
2900     const char* src = _java_class_path->value();
2901 
2902     // skip over all the leading empty paths
2903     while (*src == separator) {
2904       src ++;
2905     }
2906 
2907     char* copy = os::strdup_check_oom(src, mtArguments);
2908 
2909     // trim all trailing empty paths
2910     for (char* tail = copy + strlen(copy) - 1; tail >= copy && *tail == separator; tail--) {
2911       *tail = '\0';
2912     }
2913 
2914     char from[3] = {separator, separator, '\0'};
2915     char to  [2] = {separator, '\0'};
2916     while (StringUtils::replace_no_expand(copy, from, to) > 0) {
2917       // Keep replacing "::" -> ":" until we have no more "::" (non-windows)
2918       // Keep replacing ";;" -> ";" until we have no more ";;" (windows)
2919     }
2920 
2921     _java_class_path->set_writeable_value(copy);
2922     FreeHeap(copy); // a copy was made by set_value, so don't need this anymore
2923   }
2924 }
2925 
2926 jint Arguments::finalize_vm_init_args() {
2927   // check if the default lib/endorsed directory exists; if so, error
2928   char path[JVM_MAXPATHLEN];
2929   const char* fileSep = os::file_separator();
2930   jio_snprintf(path, JVM_MAXPATHLEN, "%s%slib%sendorsed", Arguments::get_java_home(), fileSep, fileSep);
2931 
2932   DIR* dir = os::opendir(path);
2933   if (dir != nullptr) {
2934     jio_fprintf(defaultStream::output_stream(),
2935       "<JAVA_HOME>/lib/endorsed is not supported. Endorsed standards and standalone APIs\n"
2936       "in modular form will be supported via the concept of upgradeable modules.\n");
2937     os::closedir(dir);
2938     return JNI_ERR;
2939   }
2940 
2941   jio_snprintf(path, JVM_MAXPATHLEN, "%s%slib%sext", Arguments::get_java_home(), fileSep, fileSep);
2942   dir = os::opendir(path);
2943   if (dir != nullptr) {
2944     jio_fprintf(defaultStream::output_stream(),
2945       "<JAVA_HOME>/lib/ext exists, extensions mechanism no longer supported; "
2946       "Use -classpath instead.\n.");
2947     os::closedir(dir);
2948     return JNI_ERR;
2949   }
2950 
2951   // This must be done after all arguments have been processed
2952   // and the container support has been initialized since AggressiveHeap
2953   // relies on the amount of total memory available.
2954   if (AggressiveHeap) {
2955     jint result = set_aggressive_heap_flags();
2956     if (result != JNI_OK) {
2957       return result;
2958     }
2959   }
2960 
2961   // CompileThresholdScaling == 0.0 is same as -Xint: Disable compilation (enable interpreter-only mode),
2962   // but like -Xint, leave compilation thresholds unaffected.
2963   // With tiered compilation disabled, setting CompileThreshold to 0 disables compilation as well.
2964   if ((CompileThresholdScaling == 0.0) || (!TieredCompilation && CompileThreshold == 0)) {
2965     set_mode_flags(_int);
2966   }
2967 
2968 #ifdef ZERO
2969   // Zero always runs in interpreted mode
2970   set_mode_flags(_int);
2971 #endif
2972 
2973   // eventually fix up InitialTenuringThreshold if only MaxTenuringThreshold is set
2974   if (FLAG_IS_DEFAULT(InitialTenuringThreshold) && (InitialTenuringThreshold > MaxTenuringThreshold)) {
2975     FLAG_SET_ERGO(InitialTenuringThreshold, MaxTenuringThreshold);
2976   }
2977 
2978 #if !COMPILER2_OR_JVMCI
2979   // Don't degrade server performance for footprint
2980   if (FLAG_IS_DEFAULT(UseLargePages) &&
2981       MaxHeapSize < LargePageHeapSizeThreshold) {
2982     // No need for large granularity pages w/small heaps.
2983     // Note that large pages are enabled/disabled for both the
2984     // Java heap and the code cache.
2985     FLAG_SET_DEFAULT(UseLargePages, false);
2986   }
2987 
2988   UNSUPPORTED_OPTION(ProfileInterpreter);
2989 #endif
2990 
2991   // Parse the CompilationMode flag
2992   if (!CompilationModeFlag::initialize()) {
2993     return JNI_ERR;
2994   }
2995 
2996   ClassLoader::set_preview_mode(is_valhalla_enabled());
2997 
2998   if (!check_vm_args_consistency()) {
2999     return JNI_ERR;
3000   }
3001 
3002 #ifndef CAN_SHOW_REGISTERS_ON_ASSERT
3003   UNSUPPORTED_OPTION(ShowRegistersOnAssert);
3004 #endif // CAN_SHOW_REGISTERS_ON_ASSERT
3005 
3006   return JNI_OK;
3007 }
3008 
3009 // Helper class for controlling the lifetime of JavaVMInitArgs
3010 // objects.  The contents of the JavaVMInitArgs are guaranteed to be
3011 // deleted on the destruction of the ScopedVMInitArgs object.
3012 class ScopedVMInitArgs : public StackObj {
3013  private:
3014   JavaVMInitArgs _args;
3015   char*          _container_name;
3016   bool           _is_set;
3017   char*          _vm_options_file_arg;
3018 
3019  public:
3020   ScopedVMInitArgs(const char *container_name) {
3021     _args.version = JNI_VERSION_1_2;
3022     _args.nOptions = 0;
3023     _args.options = nullptr;
3024     _args.ignoreUnrecognized = false;
3025     _container_name = (char *)container_name;
3026     _is_set = false;
3027     _vm_options_file_arg = nullptr;
3028   }
3029 
3030   // Populates the JavaVMInitArgs object represented by this
3031   // ScopedVMInitArgs object with the arguments in options.  The
3032   // allocated memory is deleted by the destructor.  If this method
3033   // returns anything other than JNI_OK, then this object is in a
3034   // partially constructed state, and should be abandoned.
3035   jint set_args(const GrowableArrayView<JavaVMOption>* options) {
3036     _is_set = true;
3037     JavaVMOption* options_arr = NEW_C_HEAP_ARRAY_RETURN_NULL(
3038         JavaVMOption, options->length(), mtArguments);
3039     if (options_arr == nullptr) {
3040       return JNI_ENOMEM;
3041     }
3042     _args.options = options_arr;
3043 
3044     for (int i = 0; i < options->length(); i++) {
3045       options_arr[i] = options->at(i);
3046       options_arr[i].optionString = os::strdup(options_arr[i].optionString);
3047       if (options_arr[i].optionString == nullptr) {
3048         // Rely on the destructor to do cleanup.
3049         _args.nOptions = i;
3050         return JNI_ENOMEM;
3051       }
3052     }
3053 
3054     _args.nOptions = options->length();
3055     _args.ignoreUnrecognized = IgnoreUnrecognizedVMOptions;
3056     return JNI_OK;
3057   }
3058 
3059   JavaVMInitArgs* get()             { return &_args; }
3060   char* container_name()            { return _container_name; }
3061   bool  is_set()                    { return _is_set; }
3062   bool  found_vm_options_file_arg() { return _vm_options_file_arg != nullptr; }
3063   char* vm_options_file_arg()       { return _vm_options_file_arg; }
3064 
3065   void set_vm_options_file_arg(const char *vm_options_file_arg) {
3066     if (_vm_options_file_arg != nullptr) {
3067       os::free(_vm_options_file_arg);
3068     }
3069     _vm_options_file_arg = os::strdup_check_oom(vm_options_file_arg);
3070   }
3071 
3072   ~ScopedVMInitArgs() {
3073     if (_vm_options_file_arg != nullptr) {
3074       os::free(_vm_options_file_arg);
3075     }
3076     if (_args.options == nullptr) return;
3077     for (int i = 0; i < _args.nOptions; i++) {
3078       os::free(_args.options[i].optionString);
3079     }
3080     FREE_C_HEAP_ARRAY(JavaVMOption, _args.options);
3081   }
3082 
3083   // Insert options into this option list, to replace option at
3084   // vm_options_file_pos (-XX:VMOptionsFile)
3085   jint insert(const JavaVMInitArgs* args,
3086               const JavaVMInitArgs* args_to_insert,
3087               const int vm_options_file_pos) {
3088     assert(_args.options == nullptr, "shouldn't be set yet");
3089     assert(args_to_insert->nOptions != 0, "there should be args to insert");
3090     assert(vm_options_file_pos != -1, "vm_options_file_pos should be set");
3091 
3092     int length = args->nOptions + args_to_insert->nOptions - 1;
3093     // Construct new option array
3094     GrowableArrayCHeap<JavaVMOption, mtArguments> options(length);
3095     for (int i = 0; i < args->nOptions; i++) {
3096       if (i == vm_options_file_pos) {
3097         // insert the new options starting at the same place as the
3098         // -XX:VMOptionsFile option
3099         for (int j = 0; j < args_to_insert->nOptions; j++) {
3100           options.push(args_to_insert->options[j]);
3101         }
3102       } else {
3103         options.push(args->options[i]);
3104       }
3105     }
3106     // make into options array
3107     return set_args(&options);
3108   }
3109 };
3110 
3111 jint Arguments::parse_java_options_environment_variable(ScopedVMInitArgs* args) {
3112   return parse_options_environment_variable("_JAVA_OPTIONS", args);
3113 }
3114 
3115 jint Arguments::parse_java_tool_options_environment_variable(ScopedVMInitArgs* args) {
3116   return parse_options_environment_variable("JAVA_TOOL_OPTIONS", args);
3117 }
3118 
3119 static JavaVMOption* get_last_aotmode_arg(const JavaVMInitArgs* args) {
3120   for (int index = args->nOptions - 1; index >= 0; index--) {
3121     JavaVMOption* option = args->options + index;
3122     if (strstr(option->optionString, "-XX:AOTMode=") == option->optionString) {
3123       return option;
3124     }
3125   }
3126 
3127   return nullptr;
3128 }
3129 
3130 jint Arguments::parse_jdk_aot_vm_options_environment_variable(GrowableArrayCHeap<VMInitArgsGroup, mtArguments>* all_args,
3131                                                             ScopedVMInitArgs* jdk_aot_vm_options_args) {
3132   // Don't bother scanning all the args if this env variable is not set
3133   if (::getenv("JDK_AOT_VM_OPTIONS") == nullptr) {
3134     return JNI_OK;
3135   }
3136 
3137   // Scan backwards and find the last occurrence of -XX:AOTMode=xxx, which will decide the value
3138   // of AOTMode.
3139   JavaVMOption* option = nullptr;
3140   for (int i = all_args->length() - 1; i >= 0; i--) {
3141     if ((option = get_last_aotmode_arg(all_args->at(i)._args)) != nullptr) {
3142       break;
3143     }
3144   }
3145 
3146   if (option != nullptr) {
3147     // We have found the last -XX:AOTMode=xxx. At this point <option> has NOT been parsed yet,
3148     // so its value is not reflected inside the global variable AOTMode.
3149     if (strcmp(option->optionString, "-XX:AOTMode=create") != 0) {
3150       return JNI_OK; // Do not parse JDK_AOT_VM_OPTIONS
3151     }
3152   } else {
3153     // -XX:AOTMode is not specified in any of 4 options_args, let's check AOTMode,
3154     // which would have been set inside process_settings_file();
3155     if (AOTMode == nullptr || strcmp(AOTMode, "create") != 0) {
3156       return JNI_OK; // Do not parse JDK_AOT_VM_OPTIONS
3157     }
3158   }
3159 
3160   return parse_options_environment_variable("JDK_AOT_VM_OPTIONS", jdk_aot_vm_options_args);
3161 }
3162 
3163 jint Arguments::parse_options_environment_variable(const char* name,
3164                                                    ScopedVMInitArgs* vm_args) {
3165   char *buffer = ::getenv(name);
3166 
3167   // Don't check this environment variable if user has special privileges
3168   // (e.g. unix su command).
3169   if (buffer == nullptr || os::have_special_privileges()) {
3170     return JNI_OK;
3171   }
3172 
3173   if ((buffer = os::strdup(buffer)) == nullptr) {
3174     return JNI_ENOMEM;
3175   }
3176 
3177   jio_fprintf(defaultStream::error_stream(),
3178               "Picked up %s: %s\n", name, buffer);
3179 
3180   int retcode = parse_options_buffer(name, buffer, strlen(buffer), vm_args);
3181 
3182   os::free(buffer);
3183   return retcode;
3184 }
3185 
3186 jint Arguments::parse_vm_options_file(const char* file_name, ScopedVMInitArgs* vm_args) {
3187   // read file into buffer
3188   int fd = ::open(file_name, O_RDONLY);
3189   if (fd < 0) {
3190     jio_fprintf(defaultStream::error_stream(),
3191                 "Could not open options file '%s'\n",
3192                 file_name);
3193     return JNI_ERR;
3194   }
3195 
3196   struct stat stbuf;
3197   int retcode = os::stat(file_name, &stbuf);
3198   if (retcode != 0) {
3199     jio_fprintf(defaultStream::error_stream(),
3200                 "Could not stat options file '%s'\n",
3201                 file_name);
3202     ::close(fd);
3203     return JNI_ERR;
3204   }
3205 
3206   if (stbuf.st_size == 0) {
3207     // tell caller there is no option data and that is ok
3208     ::close(fd);
3209     return JNI_OK;
3210   }
3211 
3212   // '+ 1' for null termination even with max bytes
3213   size_t bytes_alloc = stbuf.st_size + 1;
3214 
3215   char *buf = NEW_C_HEAP_ARRAY_RETURN_NULL(char, bytes_alloc, mtArguments);
3216   if (nullptr == buf) {
3217     jio_fprintf(defaultStream::error_stream(),
3218                 "Could not allocate read buffer for options file parse\n");
3219     ::close(fd);
3220     return JNI_ENOMEM;
3221   }
3222 
3223   memset(buf, 0, bytes_alloc);
3224 
3225   // Fill buffer
3226   ssize_t bytes_read = ::read(fd, (void *)buf, (unsigned)bytes_alloc);
3227   ::close(fd);
3228   if (bytes_read < 0) {
3229     FREE_C_HEAP_ARRAY(char, buf);
3230     jio_fprintf(defaultStream::error_stream(),
3231                 "Could not read options file '%s'\n", file_name);
3232     return JNI_ERR;
3233   }
3234 
3235   if (bytes_read == 0) {
3236     // tell caller there is no option data and that is ok
3237     FREE_C_HEAP_ARRAY(char, buf);
3238     return JNI_OK;
3239   }
3240 
3241   retcode = parse_options_buffer(file_name, buf, bytes_read, vm_args);
3242 
3243   FREE_C_HEAP_ARRAY(char, buf);
3244   return retcode;
3245 }
3246 
3247 jint Arguments::parse_options_buffer(const char* name, char* buffer, const size_t buf_len, ScopedVMInitArgs* vm_args) {
3248   // Construct option array
3249   GrowableArrayCHeap<JavaVMOption, mtArguments> options(2);
3250 
3251   // some pointers to help with parsing
3252   char *buffer_end = buffer + buf_len;
3253   char *opt_hd = buffer;
3254   char *wrt = buffer;
3255   char *rd = buffer;
3256 
3257   // parse all options
3258   while (rd < buffer_end) {
3259     // skip leading white space from the input string
3260     while (rd < buffer_end && isspace((unsigned char) *rd)) {
3261       rd++;
3262     }
3263 
3264     if (rd >= buffer_end) {
3265       break;
3266     }
3267 
3268     // Remember this is where we found the head of the token.
3269     opt_hd = wrt;
3270 
3271     // Tokens are strings of non white space characters separated
3272     // by one or more white spaces.
3273     while (rd < buffer_end && !isspace((unsigned char) *rd)) {
3274       if (*rd == '\'' || *rd == '"') {      // handle a quoted string
3275         int quote = *rd;                    // matching quote to look for
3276         rd++;                               // don't copy open quote
3277         while (rd < buffer_end && *rd != quote) {
3278                                             // include everything (even spaces)
3279                                             // up until the close quote
3280           *wrt++ = *rd++;                   // copy to option string
3281         }
3282 
3283         if (rd < buffer_end) {
3284           rd++;                             // don't copy close quote
3285         } else {
3286                                             // did not see closing quote
3287           jio_fprintf(defaultStream::error_stream(),
3288                       "Unmatched quote in %s\n", name);
3289           return JNI_ERR;
3290         }
3291       } else {
3292         *wrt++ = *rd++;                     // copy to option string
3293       }
3294     }
3295 
3296     // steal a white space character and set it to null
3297     *wrt++ = '\0';
3298     // We now have a complete token
3299 
3300     JavaVMOption option;
3301     option.optionString = opt_hd;
3302     option.extraInfo = nullptr;
3303 
3304     options.append(option);                // Fill in option
3305 
3306     rd++;  // Advance to next character
3307   }
3308 
3309   // Fill out JavaVMInitArgs structure.
3310   return vm_args->set_args(&options);
3311 }
3312 
3313 #ifndef PRODUCT
3314 // Determine whether LogVMOutput should be implicitly turned on.
3315 static bool use_vm_log() {
3316   if (LogCompilation || !FLAG_IS_DEFAULT(LogFile) ||
3317       PrintCompilation || PrintInlining || PrintDependencies || PrintNativeNMethods ||
3318       PrintDebugInfo || PrintRelocations || PrintNMethods || PrintExceptionHandlers ||
3319       PrintAssembly || TraceDeoptimization ||
3320       (VerifyDependencies && FLAG_IS_CMDLINE(VerifyDependencies))) {
3321     return true;
3322   }
3323 
3324 #ifdef COMPILER1
3325   if (PrintC1Statistics) {
3326     return true;
3327   }
3328 #endif // COMPILER1
3329 
3330 #ifdef COMPILER2
3331   if (PrintOptoAssembly || PrintOptoStatistics) {
3332     return true;
3333   }
3334 #endif // COMPILER2
3335 
3336   return false;
3337 }
3338 
3339 #endif // PRODUCT
3340 
3341 bool Arguments::args_contains_vm_options_file_arg(const JavaVMInitArgs* args) {
3342   for (int index = 0; index < args->nOptions; index++) {
3343     const JavaVMOption* option = args->options + index;
3344     const char* tail;
3345     if (match_option(option, "-XX:VMOptionsFile=", &tail)) {
3346       return true;
3347     }
3348   }
3349   return false;
3350 }
3351 
3352 jint Arguments::insert_vm_options_file(const JavaVMInitArgs* args,
3353                                        const char* vm_options_file,
3354                                        const int vm_options_file_pos,
3355                                        ScopedVMInitArgs* vm_options_file_args,
3356                                        ScopedVMInitArgs* args_out) {
3357   jint code = parse_vm_options_file(vm_options_file, vm_options_file_args);
3358   if (code != JNI_OK) {
3359     return code;
3360   }
3361 
3362   if (vm_options_file_args->get()->nOptions < 1) {
3363     return JNI_OK;
3364   }
3365 
3366   if (args_contains_vm_options_file_arg(vm_options_file_args->get())) {
3367     jio_fprintf(defaultStream::error_stream(),
3368                 "A VM options file may not refer to a VM options file. "
3369                 "Specification of '-XX:VMOptionsFile=<file-name>' in the "
3370                 "options file '%s' in options container '%s' is an error.\n",
3371                 vm_options_file_args->vm_options_file_arg(),
3372                 vm_options_file_args->container_name());
3373     return JNI_EINVAL;
3374   }
3375 
3376   return args_out->insert(args, vm_options_file_args->get(),
3377                           vm_options_file_pos);
3378 }
3379 
3380 // Expand -XX:VMOptionsFile found in args_in as needed.
3381 // mod_args and args_out parameters may return values as needed.
3382 jint Arguments::expand_vm_options_as_needed(const JavaVMInitArgs* args_in,
3383                                             ScopedVMInitArgs* mod_args,
3384                                             JavaVMInitArgs** args_out) {
3385   jint code = match_special_option_and_act(args_in, mod_args);
3386   if (code != JNI_OK) {
3387     return code;
3388   }
3389 
3390   if (mod_args->is_set()) {
3391     // args_in contains -XX:VMOptionsFile and mod_args contains the
3392     // original options from args_in along with the options expanded
3393     // from the VMOptionsFile. Return a short-hand to the caller.
3394     *args_out = mod_args->get();
3395   } else {
3396     *args_out = (JavaVMInitArgs *)args_in;  // no changes so use args_in
3397   }
3398   return JNI_OK;
3399 }
3400 
3401 jint Arguments::match_special_option_and_act(const JavaVMInitArgs* args,
3402                                              ScopedVMInitArgs* args_out) {
3403   // Remaining part of option string
3404   const char* tail;
3405   ScopedVMInitArgs vm_options_file_args(args_out->container_name());
3406 
3407   for (int index = 0; index < args->nOptions; index++) {
3408     const JavaVMOption* option = args->options + index;
3409     if (match_option(option, "-XX:Flags=", &tail)) {
3410       Arguments::set_jvm_flags_file(tail);
3411       continue;
3412     }
3413     if (match_option(option, "-XX:VMOptionsFile=", &tail)) {
3414       if (vm_options_file_args.found_vm_options_file_arg()) {
3415         jio_fprintf(defaultStream::error_stream(),
3416                     "The option '%s' is already specified in the options "
3417                     "container '%s' so the specification of '%s' in the "
3418                     "same options container is an error.\n",
3419                     vm_options_file_args.vm_options_file_arg(),
3420                     vm_options_file_args.container_name(),
3421                     option->optionString);
3422         return JNI_EINVAL;
3423       }
3424       vm_options_file_args.set_vm_options_file_arg(option->optionString);
3425       // If there's a VMOptionsFile, parse that
3426       jint code = insert_vm_options_file(args, tail, index,
3427                                          &vm_options_file_args, args_out);
3428       if (code != JNI_OK) {
3429         return code;
3430       }
3431       args_out->set_vm_options_file_arg(vm_options_file_args.vm_options_file_arg());
3432       if (args_out->is_set()) {
3433         // The VMOptions file inserted some options so switch 'args'
3434         // to the new set of options, and continue processing which
3435         // preserves "last option wins" semantics.
3436         args = args_out->get();
3437         // The first option from the VMOptionsFile replaces the
3438         // current option.  So we back track to process the
3439         // replacement option.
3440         index--;
3441       }
3442       continue;
3443     }
3444     if (match_option(option, "-XX:+PrintVMOptions")) {
3445       PrintVMOptions = true;
3446       continue;
3447     }
3448     if (match_option(option, "-XX:-PrintVMOptions")) {
3449       PrintVMOptions = false;
3450       continue;
3451     }
3452     if (match_option(option, "-XX:+IgnoreUnrecognizedVMOptions")) {
3453       IgnoreUnrecognizedVMOptions = true;
3454       continue;
3455     }
3456     if (match_option(option, "-XX:-IgnoreUnrecognizedVMOptions")) {
3457       IgnoreUnrecognizedVMOptions = false;
3458       continue;
3459     }
3460     if (match_option(option, "-XX:+PrintFlagsInitial")) {
3461       JVMFlag::printFlags(tty, false);
3462       vm_exit(0);
3463     }
3464 
3465 #ifndef PRODUCT
3466     if (match_option(option, "-XX:+PrintFlagsWithComments")) {
3467       JVMFlag::printFlags(tty, true);
3468       vm_exit(0);
3469     }
3470 #endif
3471   }
3472   return JNI_OK;
3473 }
3474 
3475 static void print_options(const JavaVMInitArgs *args) {
3476   const char* tail;
3477   for (int index = 0; index < args->nOptions; index++) {
3478     const JavaVMOption *option = args->options + index;
3479     if (match_option(option, "-XX:", &tail)) {
3480       logOption(tail);
3481     }
3482   }
3483 }
3484 
3485 bool Arguments::handle_deprecated_print_gc_flags() {
3486   if (PrintGC) {
3487     log_warning(gc)("-XX:+PrintGC is deprecated. Will use -Xlog:gc instead.");
3488   }
3489   if (PrintGCDetails) {
3490     log_warning(gc)("-XX:+PrintGCDetails is deprecated. Will use -Xlog:gc* instead.");
3491   }
3492 
3493   if (_legacyGCLogging.lastFlag == 2) {
3494     // -Xloggc was used to specify a filename
3495     const char* gc_conf = PrintGCDetails ? "gc*" : "gc";
3496 
3497     LogTarget(Error, logging) target;
3498     LogStream errstream(target);
3499     return LogConfiguration::parse_log_arguments(_legacyGCLogging.file, gc_conf, nullptr, nullptr, &errstream);
3500   } else if (PrintGC || PrintGCDetails || (_legacyGCLogging.lastFlag == 1)) {
3501     LogConfiguration::configure_stdout(LogLevel::Info, !PrintGCDetails, LOG_TAGS(gc));
3502   }
3503   return true;
3504 }
3505 
3506 static void apply_debugger_ergo() {
3507 #ifdef ASSERT
3508   if (ReplayCompiles) {
3509     FLAG_SET_ERGO_IF_DEFAULT(UseDebuggerErgo, true);
3510   }
3511 
3512   if (UseDebuggerErgo) {
3513     // Turn on sub-flags
3514     FLAG_SET_ERGO_IF_DEFAULT(UseDebuggerErgo1, true);
3515     FLAG_SET_ERGO_IF_DEFAULT(UseDebuggerErgo2, true);
3516   }
3517 
3518   if (UseDebuggerErgo2) {
3519     // Debugging with limited number of CPUs
3520     FLAG_SET_ERGO_IF_DEFAULT(UseNUMA, false);
3521     FLAG_SET_ERGO_IF_DEFAULT(ConcGCThreads, 1);
3522     FLAG_SET_ERGO_IF_DEFAULT(ParallelGCThreads, 1);
3523     FLAG_SET_ERGO_IF_DEFAULT(CICompilerCount, 2);
3524   }
3525 #endif // ASSERT
3526 }
3527 
3528 // Parse entry point called from JNI_CreateJavaVM
3529 
3530 jint Arguments::parse(const JavaVMInitArgs* initial_cmd_args) {
3531   assert(verify_special_jvm_flags(false), "deprecated and obsolete flag table inconsistent");
3532   JVMFlag::check_all_flag_declarations();
3533 
3534   // If flag "-XX:Flags=flags-file" is used it will be the first option to be processed.
3535   const char* hotspotrc = ".hotspotrc";
3536   bool settings_file_specified = false;
3537   bool needs_hotspotrc_warning = false;
3538   ScopedVMInitArgs initial_vm_options_args("");
3539   ScopedVMInitArgs initial_java_tool_options_args("env_var='JAVA_TOOL_OPTIONS'");
3540   ScopedVMInitArgs initial_java_options_args("env_var='_JAVA_OPTIONS'");
3541   ScopedVMInitArgs initial_jdk_aot_vm_options_args("env_var='JDK_AOT_VM_OPTIONS'");
3542 
3543   // Pointers to current working set of containers
3544   JavaVMInitArgs* cur_cmd_args;
3545   JavaVMInitArgs* cur_vm_options_args;
3546   JavaVMInitArgs* cur_java_options_args;
3547   JavaVMInitArgs* cur_java_tool_options_args;
3548   JavaVMInitArgs* cur_jdk_aot_vm_options_args;
3549 
3550   // Containers for modified/expanded options
3551   ScopedVMInitArgs mod_cmd_args("cmd_line_args");
3552   ScopedVMInitArgs mod_vm_options_args("vm_options_args");
3553   ScopedVMInitArgs mod_java_tool_options_args("env_var='JAVA_TOOL_OPTIONS'");
3554   ScopedVMInitArgs mod_java_options_args("env_var='_JAVA_OPTIONS'");
3555   ScopedVMInitArgs mod_jdk_aot_vm_options_args("env_var='_JDK_AOT_VM_OPTIONS'");
3556 
3557   GrowableArrayCHeap<VMInitArgsGroup, mtArguments> all_args;
3558 
3559   jint code =
3560       parse_java_tool_options_environment_variable(&initial_java_tool_options_args);
3561   if (code != JNI_OK) {
3562     return code;
3563   }
3564 
3565   // Yet another environment variable: _JAVA_OPTIONS. This mimics the classic VM.
3566   // This is an undocumented feature.
3567   code = parse_java_options_environment_variable(&initial_java_options_args);
3568   if (code != JNI_OK) {
3569     return code;
3570   }
3571 
3572   // Parse the options in the /java.base/jdk/internal/vm/options resource, if present
3573   char *vmoptions = ClassLoader::lookup_vm_options();
3574   if (vmoptions != nullptr) {
3575     code = parse_options_buffer("vm options resource", vmoptions, strlen(vmoptions), &initial_vm_options_args);
3576     FREE_C_HEAP_ARRAY(char, vmoptions);
3577     if (code != JNI_OK) {
3578       return code;
3579     }
3580   }
3581 
3582   code = expand_vm_options_as_needed(initial_java_tool_options_args.get(),
3583                                      &mod_java_tool_options_args,
3584                                      &cur_java_tool_options_args);
3585   if (code != JNI_OK) {
3586     return code;
3587   }
3588 
3589   code = expand_vm_options_as_needed(initial_cmd_args,
3590                                      &mod_cmd_args,
3591                                      &cur_cmd_args);
3592   if (code != JNI_OK) {
3593     return code;
3594   }
3595 
3596   code = expand_vm_options_as_needed(initial_java_options_args.get(),
3597                                      &mod_java_options_args,
3598                                      &cur_java_options_args);
3599   if (code != JNI_OK) {
3600     return code;
3601   }
3602 
3603   code = expand_vm_options_as_needed(initial_vm_options_args.get(),
3604                                      &mod_vm_options_args,
3605                                      &cur_vm_options_args);
3606   if (code != JNI_OK) {
3607     return code;
3608   }
3609 
3610   const char* flags_file = Arguments::get_jvm_flags_file();
3611   settings_file_specified = (flags_file != nullptr);
3612 
3613   // Parse specified settings file (s) -- the effects are applied immediately into the JVM global flags.
3614   if (settings_file_specified) {
3615     if (!process_settings_file(flags_file, true,
3616                                IgnoreUnrecognizedVMOptions)) {
3617       return JNI_EINVAL;
3618     }
3619   } else {
3620 #ifdef ASSERT
3621     // Parse default .hotspotrc settings file
3622     if (!process_settings_file(".hotspotrc", false,
3623                                IgnoreUnrecognizedVMOptions)) {
3624       return JNI_EINVAL;
3625     }
3626 #else
3627     struct stat buf;
3628     if (os::stat(hotspotrc, &buf) == 0) {
3629       needs_hotspotrc_warning = true;
3630     }
3631 #endif
3632   }
3633 
3634   // The settings in the args are applied in this order to the the JVM global flags.
3635   // For historical reasons, the order is DIFFERENT than the scanning order of
3636   // the above expand_vm_options_as_needed() calls.
3637   all_args.append({cur_vm_options_args, JVMFlagOrigin::JIMAGE_RESOURCE});
3638   all_args.append({cur_java_tool_options_args, JVMFlagOrigin::ENVIRON_VAR});
3639   all_args.append({cur_cmd_args, JVMFlagOrigin::COMMAND_LINE});
3640   all_args.append({cur_java_options_args, JVMFlagOrigin::ENVIRON_VAR});
3641 
3642   // JDK_AOT_VM_OPTIONS are parsed only if -XX:AOTMode=create has been detected from all
3643   // the options that have been gathered above.
3644   code = parse_jdk_aot_vm_options_environment_variable(&all_args, &initial_jdk_aot_vm_options_args);
3645   if (code != JNI_OK) {
3646     return code;
3647   }
3648   code = expand_vm_options_as_needed(initial_jdk_aot_vm_options_args.get(),
3649                                      &mod_jdk_aot_vm_options_args,
3650                                      &cur_jdk_aot_vm_options_args);
3651   if (code != JNI_OK) {
3652     return code;
3653   }
3654 
3655   for (int index = 0; index < cur_jdk_aot_vm_options_args->nOptions; index++) {
3656     JavaVMOption* option = cur_jdk_aot_vm_options_args->options + index;
3657     const char* optionString = option->optionString;
3658     if (strstr(optionString, "-XX:AOTMode=") == optionString &&
3659         strcmp(optionString, "-XX:AOTMode=create") != 0) {
3660       jio_fprintf(defaultStream::error_stream(),
3661                   "Option %s cannot be specified in JDK_AOT_VM_OPTIONS\n", optionString);
3662       return JNI_ERR;
3663     }
3664   }
3665 
3666   all_args.append({cur_jdk_aot_vm_options_args, JVMFlagOrigin::ENVIRON_VAR});
3667 
3668   if (IgnoreUnrecognizedVMOptions) {
3669     // Note: unrecognized options in cur_vm_options_arg cannot be ignored. They are part of
3670     // the JDK so it shouldn't have bad options.
3671     cur_cmd_args->ignoreUnrecognized = true;
3672     cur_java_tool_options_args->ignoreUnrecognized = true;
3673     cur_java_options_args->ignoreUnrecognized = true;
3674     cur_jdk_aot_vm_options_args->ignoreUnrecognized = true;
3675   }
3676 
3677   if (PrintVMOptions) {
3678     // For historical reasons, options specified in cur_vm_options_arg and -XX:Flags are not printed.
3679     print_options(cur_java_tool_options_args);
3680     print_options(cur_cmd_args);
3681     print_options(cur_java_options_args);
3682     print_options(cur_jdk_aot_vm_options_args);
3683   }
3684 
3685   // Apply the settings in these args to the JVM global flags.
3686   jint result = parse_vm_init_args(&all_args);
3687 
3688   if (result != JNI_OK) {
3689     return result;
3690   }
3691 
3692   // Delay warning until here so that we've had a chance to process
3693   // the -XX:-PrintWarnings flag
3694   if (needs_hotspotrc_warning) {
3695     warning("%s file is present but has been ignored.  "
3696             "Run with -XX:Flags=%s to load the file.",
3697             hotspotrc, hotspotrc);
3698   }
3699 
3700   if (needs_module_property_warning) {
3701     warning("Ignoring system property options whose names match the '-Djdk.module.*'."
3702             " names that are reserved for internal use.");
3703   }
3704 
3705 #if defined(_ALLBSD_SOURCE) || defined(AIX)  // UseLargePages is not yet supported on BSD and AIX.
3706   UNSUPPORTED_OPTION(UseLargePages);
3707 #endif
3708 
3709 #if defined(AIX)
3710   UNSUPPORTED_OPTION_NULL(AllocateHeapAt);
3711 #endif
3712 
3713 #ifndef PRODUCT
3714   if (TraceBytecodesAt != 0) {
3715     TraceBytecodes = true;
3716   }
3717 #endif // PRODUCT
3718 
3719   if (ScavengeRootsInCode == 0) {
3720     if (!FLAG_IS_DEFAULT(ScavengeRootsInCode)) {
3721       warning("Forcing ScavengeRootsInCode non-zero");
3722     }
3723     ScavengeRootsInCode = 1;
3724   }
3725 
3726   if (!handle_deprecated_print_gc_flags()) {
3727     return JNI_EINVAL;
3728   }
3729 
3730   // Set object alignment values.
3731   set_object_alignment();
3732 
3733 #if !INCLUDE_CDS
3734   if (CDSConfig::is_dumping_static_archive() || RequireSharedSpaces) {
3735     jio_fprintf(defaultStream::error_stream(),
3736       "Shared spaces are not supported in this VM\n");
3737     return JNI_ERR;
3738   }
3739   if (DumpLoadedClassList != nullptr) {
3740     jio_fprintf(defaultStream::error_stream(),
3741       "DumpLoadedClassList is not supported in this VM\n");
3742     return JNI_ERR;
3743   }
3744   if ((CDSConfig::is_using_archive() && xshare_auto_cmd_line) ||
3745       log_is_enabled(Info, cds) || log_is_enabled(Info, aot)) {
3746     warning("Shared spaces are not supported in this VM");
3747     UseSharedSpaces = false;
3748     LogConfiguration::configure_stdout(LogLevel::Off, true, LOG_TAGS(cds));
3749     LogConfiguration::configure_stdout(LogLevel::Off, true, LOG_TAGS(aot));
3750   }
3751   no_shared_spaces("CDS Disabled");
3752 #endif // INCLUDE_CDS
3753 
3754   // Verify NMT arguments
3755   const NMT_TrackingLevel lvl = NMTUtil::parse_tracking_level(NativeMemoryTracking);
3756   if (lvl == NMT_unknown) {
3757     jio_fprintf(defaultStream::error_stream(),
3758                 "Syntax error, expecting -XX:NativeMemoryTracking=[off|summary|detail]\n");
3759     return JNI_ERR;
3760   }
3761   if (PrintNMTStatistics && lvl == NMT_off) {
3762     warning("PrintNMTStatistics is disabled, because native memory tracking is not enabled");
3763     FLAG_SET_DEFAULT(PrintNMTStatistics, false);
3764   }
3765 
3766   bool trace_dependencies = log_is_enabled(Debug, dependencies);
3767   if (trace_dependencies && VerifyDependencies) {
3768     warning("dependency logging results may be inflated by VerifyDependencies");
3769   }
3770 
3771   bool log_class_load_cause = log_is_enabled(Info, class, load, cause, native) ||
3772                               log_is_enabled(Info, class, load, cause);
3773   if (log_class_load_cause && LogClassLoadingCauseFor == nullptr) {
3774     warning("class load cause logging will not produce output without LogClassLoadingCauseFor");
3775   }
3776 
3777   apply_debugger_ergo();
3778 
3779   // The VMThread needs to stop now and then to execute these debug options.
3780   if ((HandshakeALot || SafepointALot) && FLAG_IS_DEFAULT(GuaranteedSafepointInterval)) {
3781     FLAG_SET_DEFAULT(GuaranteedSafepointInterval, 1000);
3782   }
3783 
3784   if (log_is_enabled(Info, arguments)) {
3785     LogStream st(Log(arguments)::info());
3786     Arguments::print_on(&st);
3787   }
3788 
3789   return JNI_OK;
3790 }
3791 
3792 void Arguments::set_compact_headers_flags() {
3793 #ifdef _LP64
3794   if (UseCompactObjectHeaders && FLAG_IS_CMDLINE(UseCompressedClassPointers) && !UseCompressedClassPointers) {
3795     warning("Compact object headers require compressed class pointers. Disabling compact object headers.");
3796     FLAG_SET_DEFAULT(UseCompactObjectHeaders, false);
3797   }
3798   if (UseCompactObjectHeaders && !UseObjectMonitorTable) {
3799     // If UseCompactObjectHeaders is on the command line, turn on UseObjectMonitorTable.
3800     if (FLAG_IS_CMDLINE(UseCompactObjectHeaders)) {
3801       FLAG_SET_DEFAULT(UseObjectMonitorTable, true);
3802 
3803       // If UseObjectMonitorTable is on the command line, turn off UseCompactObjectHeaders.
3804     } else if (FLAG_IS_CMDLINE(UseObjectMonitorTable)) {
3805       FLAG_SET_DEFAULT(UseCompactObjectHeaders, false);
3806       // If neither on the command line, the defaults are incompatible, but turn on UseObjectMonitorTable.
3807     } else {
3808       FLAG_SET_DEFAULT(UseObjectMonitorTable, true);
3809     }
3810   }
3811   if (UseCompactObjectHeaders && !UseCompressedClassPointers) {
3812     FLAG_SET_DEFAULT(UseCompressedClassPointers, true);
3813   }
3814 #endif
3815 }
3816 
3817 jint Arguments::apply_ergo() {
3818   // Set flags based on ergonomics.
3819   jint result = set_ergonomics_flags();
3820   if (result != JNI_OK) return result;
3821 
3822   // Set heap size based on available physical memory
3823   set_heap_size();
3824 
3825   GCConfig::arguments()->initialize();
3826 
3827   set_compact_headers_flags();
3828 
3829   if (UseCompressedClassPointers) {
3830     CompressedKlassPointers::pre_initialize();
3831   }
3832 
3833   CDSConfig::ergo_initialize();
3834 
3835   // Initialize Metaspace flags and alignments
3836   Metaspace::ergo_initialize();
3837 
3838   if (!StringDedup::ergo_initialize()) {
3839     return JNI_EINVAL;
3840   }
3841 
3842   // Set compiler flags after GC is selected and GC specific
3843   // flags (LoopStripMiningIter) are set.
3844   CompilerConfig::ergo_initialize();
3845 
3846   // Set bytecode rewriting flags
3847   set_bytecode_flags();
3848 
3849   // Set flags if aggressive optimization flags are enabled
3850   jint code = set_aggressive_opts_flags();
3851   if (code != JNI_OK) {
3852     return code;
3853   }
3854 
3855   if (FLAG_IS_DEFAULT(UseSecondarySupersTable)) {
3856     FLAG_SET_DEFAULT(UseSecondarySupersTable, VM_Version::supports_secondary_supers_table());
3857   } else if (UseSecondarySupersTable && !VM_Version::supports_secondary_supers_table()) {
3858     warning("UseSecondarySupersTable is not supported");
3859     FLAG_SET_DEFAULT(UseSecondarySupersTable, false);
3860   }
3861   if (!UseSecondarySupersTable) {
3862     FLAG_SET_DEFAULT(StressSecondarySupers, false);
3863     FLAG_SET_DEFAULT(VerifySecondarySupers, false);
3864   }
3865 
3866 #ifdef ZERO
3867   // Clear flags not supported on zero.
3868   FLAG_SET_DEFAULT(ProfileInterpreter, false);
3869 #endif // ZERO
3870 
3871   if (PrintAssembly && FLAG_IS_DEFAULT(DebugNonSafepoints)) {
3872     warning("PrintAssembly is enabled; turning on DebugNonSafepoints to gain additional output");
3873     DebugNonSafepoints = true;
3874   }
3875 
3876   if (FLAG_IS_CMDLINE(CompressedClassSpaceSize) && !UseCompressedClassPointers) {
3877     warning("Setting CompressedClassSpaceSize has no effect when compressed class pointers are not used");
3878   }
3879 
3880   // Treat the odd case where local verification is enabled but remote
3881   // verification is not as if both were enabled.
3882   if (BytecodeVerificationLocal && !BytecodeVerificationRemote) {
3883     log_info(verification)("Turning on remote verification because local verification is on");
3884     FLAG_SET_DEFAULT(BytecodeVerificationRemote, true);
3885   }
3886   if (!is_valhalla_enabled()) {
3887 #define WARN_IF_NOT_DEFAULT_FLAG(flag)                                                                       \
3888     if (!FLAG_IS_DEFAULT(flag)) {                                                                            \
3889       warning("Valhalla-specific flag \"%s\" has no effect when --enable-preview is not specified.", #flag); \
3890     }
3891 
3892 #define DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(flag)  \
3893     WARN_IF_NOT_DEFAULT_FLAG(flag)                  \
3894     FLAG_SET_DEFAULT(flag, false);
3895 
3896     DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(InlineTypePassFieldsAsArgs);
3897     DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(InlineTypeReturnedAsFields);
3898     DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(UseArrayFlattening);
3899     DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(UseFieldFlattening);
3900     DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(UseNonAtomicValueFlattening);
3901     DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(UseNullableValueFlattening);
3902     DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(UseAtomicValueFlattening);
3903     DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(PrintInlineLayout);
3904     DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(PrintFlatArrayLayout);
3905     WARN_IF_NOT_DEFAULT_FLAG(FlatArrayElementMaxOops);
3906 #ifdef ASSERT
3907     DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(StressCallingConvention);
3908     DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(PreloadClasses);
3909     WARN_IF_NOT_DEFAULT_FLAG(PrintInlineKlassFields);
3910 #endif
3911 #ifdef COMPILER1
3912     DEBUG_ONLY(DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(C1UseDelayedFlattenedFieldReads);)
3913 #endif
3914 #ifdef COMPILER2
3915     DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(UseArrayLoadStoreProfile);
3916     DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT(UseACmpProfile);
3917 #endif
3918 #undef DISABLE_FLAG_AND_WARN_IF_NOT_DEFAULT
3919 #undef WARN_IF_NOT_DEFAULT_FLAG
3920   } else {
3921     if (is_interpreter_only() && !CDSConfig::is_dumping_archive() && !UseSharedSpaces) {
3922       // Disable calling convention optimizations if inline types are not supported.
3923       // Also these aren't useful in -Xint. However, don't disable them when dumping or using
3924       // the CDS archive, as the values must match between dumptime and runtime.
3925       FLAG_SET_DEFAULT(InlineTypePassFieldsAsArgs, false);
3926       FLAG_SET_DEFAULT(InlineTypeReturnedAsFields, false);
3927     }
3928     if (!UseNonAtomicValueFlattening && !UseNullableValueFlattening && !UseAtomicValueFlattening) {
3929       // Flattening is disabled
3930       FLAG_SET_DEFAULT(UseArrayFlattening, false);
3931       FLAG_SET_DEFAULT(UseFieldFlattening, false);
3932     }
3933   }
3934 
3935 #ifndef PRODUCT
3936   if (!LogVMOutput && FLAG_IS_DEFAULT(LogVMOutput)) {
3937     if (use_vm_log()) {
3938       LogVMOutput = true;
3939     }
3940   }
3941 #endif // PRODUCT
3942 
3943   if (PrintCommandLineFlags) {
3944     JVMFlag::printSetFlags(tty);
3945   }
3946 
3947 #if COMPILER2_OR_JVMCI
3948   if (!FLAG_IS_DEFAULT(EnableVectorSupport) && !EnableVectorSupport) {
3949     if (!FLAG_IS_DEFAULT(EnableVectorReboxing) && EnableVectorReboxing) {
3950       warning("Disabling EnableVectorReboxing since EnableVectorSupport is turned off.");
3951     }
3952     FLAG_SET_DEFAULT(EnableVectorReboxing, false);
3953 
3954     if (!FLAG_IS_DEFAULT(EnableVectorAggressiveReboxing) && EnableVectorAggressiveReboxing) {
3955       if (!EnableVectorReboxing) {
3956         warning("Disabling EnableVectorAggressiveReboxing since EnableVectorReboxing is turned off.");
3957       } else {
3958         warning("Disabling EnableVectorAggressiveReboxing since EnableVectorSupport is turned off.");
3959       }
3960     }
3961     FLAG_SET_DEFAULT(EnableVectorAggressiveReboxing, false);
3962   }
3963 #endif // COMPILER2_OR_JVMCI
3964 
3965 #ifdef COMPILER2
3966   if (!FLAG_IS_DEFAULT(UseLoopPredicate) && !UseLoopPredicate && UseProfiledLoopPredicate) {
3967     warning("Disabling UseProfiledLoopPredicate since UseLoopPredicate is turned off.");
3968     FLAG_SET_ERGO(UseProfiledLoopPredicate, false);
3969   }
3970 #endif // COMPILER2
3971 
3972   if (log_is_enabled(Info, perf, class, link)) {
3973     if (!UsePerfData) {
3974       warning("Disabling -Xlog:perf+class+link since UsePerfData is turned off.");
3975       LogConfiguration::disable_tags(false, LOG_TAGS(perf, class, link));
3976       assert(!log_is_enabled(Info, perf, class, link), "sanity");
3977     }
3978   }
3979 
3980   if (FLAG_IS_CMDLINE(DiagnoseSyncOnValueBasedClasses)) {
3981     if (DiagnoseSyncOnValueBasedClasses == ObjectSynchronizer::LOG_WARNING && !log_is_enabled(Info, valuebasedclasses)) {
3982       LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(valuebasedclasses));
3983     }
3984   }
3985   return JNI_OK;
3986 }
3987 
3988 jint Arguments::adjust_after_os() {
3989   if (UseNUMA) {
3990     if (UseParallelGC) {
3991       if (FLAG_IS_DEFAULT(MinHeapDeltaBytes)) {
3992          FLAG_SET_DEFAULT(MinHeapDeltaBytes, 64*M);
3993       }
3994     }
3995   }
3996   return JNI_OK;
3997 }
3998 
3999 int Arguments::PropertyList_count(SystemProperty* pl) {
4000   int count = 0;
4001   while(pl != nullptr) {
4002     count++;
4003     pl = pl->next();
4004   }
4005   return count;
4006 }
4007 
4008 // Return the number of readable properties.
4009 int Arguments::PropertyList_readable_count(SystemProperty* pl) {
4010   int count = 0;
4011   while(pl != nullptr) {
4012     if (pl->readable()) {
4013       count++;
4014     }
4015     pl = pl->next();
4016   }
4017   return count;
4018 }
4019 
4020 const char* Arguments::PropertyList_get_value(SystemProperty *pl, const char* key) {
4021   assert(key != nullptr, "just checking");
4022   SystemProperty* prop;
4023   for (prop = pl; prop != nullptr; prop = prop->next()) {
4024     if (strcmp(key, prop->key()) == 0) return prop->value();
4025   }
4026   return nullptr;
4027 }
4028 
4029 // Return the value of the requested property provided that it is a readable property.
4030 const char* Arguments::PropertyList_get_readable_value(SystemProperty *pl, const char* key) {
4031   assert(key != nullptr, "just checking");
4032   SystemProperty* prop;
4033   // Return the property value if the keys match and the property is not internal or
4034   // it's the special internal property "jdk.boot.class.path.append".
4035   for (prop = pl; prop != nullptr; prop = prop->next()) {
4036     if (strcmp(key, prop->key()) == 0) {
4037       if (!prop->internal()) {
4038         return prop->value();
4039       } else if (strcmp(key, "jdk.boot.class.path.append") == 0) {
4040         return prop->value();
4041       } else {
4042         // Property is internal and not jdk.boot.class.path.append so return null.
4043         return nullptr;
4044       }
4045     }
4046   }
4047   return nullptr;
4048 }
4049 
4050 void Arguments::PropertyList_add(SystemProperty** plist, SystemProperty *new_p) {
4051   SystemProperty* p = *plist;
4052   if (p == nullptr) {
4053     *plist = new_p;
4054   } else {
4055     while (p->next() != nullptr) {
4056       p = p->next();
4057     }
4058     p->set_next(new_p);
4059   }
4060 }
4061 
4062 void Arguments::PropertyList_add(SystemProperty** plist, const char* k, const char* v,
4063                                  bool writeable, bool internal) {
4064   if (plist == nullptr)
4065     return;
4066 
4067   SystemProperty* new_p = new SystemProperty(k, v, writeable, internal);
4068   PropertyList_add(plist, new_p);
4069 }
4070 
4071 void Arguments::PropertyList_add(SystemProperty *element) {
4072   PropertyList_add(&_system_properties, element);
4073 }
4074 
4075 // This add maintains unique property key in the list.
4076 void Arguments::PropertyList_unique_add(SystemProperty** plist, const char* k, const char* v,
4077                                         PropertyAppendable append, PropertyWriteable writeable,
4078                                         PropertyInternal internal) {
4079   if (plist == nullptr)
4080     return;
4081 
4082   // If property key exists and is writeable, then update with new value.
4083   // Trying to update a non-writeable property is silently ignored.
4084   SystemProperty* prop;
4085   for (prop = *plist; prop != nullptr; prop = prop->next()) {
4086     if (strcmp(k, prop->key()) == 0) {
4087       if (append == AppendProperty) {
4088         prop->append_writeable_value(v);
4089       } else {
4090         prop->set_writeable_value(v);
4091       }
4092       return;
4093     }
4094   }
4095 
4096   PropertyList_add(plist, k, v, writeable == WriteableProperty, internal == InternalProperty);
4097 }
4098 
4099 // Copies src into buf, replacing "%%" with "%" and "%p" with pid
4100 // Returns true if all of the source pointed by src has been copied over to
4101 // the destination buffer pointed by buf. Otherwise, returns false.
4102 // Notes:
4103 // 1. If the length (buflen) of the destination buffer excluding the
4104 // null terminator character is not long enough for holding the expanded
4105 // pid characters, it also returns false instead of returning the partially
4106 // expanded one.
4107 // 2. The passed in "buflen" should be large enough to hold the null terminator.
4108 bool Arguments::copy_expand_pid(const char* src, size_t srclen,
4109                                 char* buf, size_t buflen) {
4110   const char* p = src;
4111   char* b = buf;
4112   const char* src_end = &src[srclen];
4113   char* buf_end = &buf[buflen - 1];
4114 
4115   while (p < src_end && b < buf_end) {
4116     if (*p == '%') {
4117       switch (*(++p)) {
4118       case '%':         // "%%" ==> "%"
4119         *b++ = *p++;
4120         break;
4121       case 'p':  {       //  "%p" ==> current process id
4122         // buf_end points to the character before the last character so
4123         // that we could write '\0' to the end of the buffer.
4124         size_t buf_sz = buf_end - b + 1;
4125         int ret = jio_snprintf(b, buf_sz, "%d", os::current_process_id());
4126 
4127         // if jio_snprintf fails or the buffer is not long enough to hold
4128         // the expanded pid, returns false.
4129         if (ret < 0 || ret >= (int)buf_sz) {
4130           return false;
4131         } else {
4132           b += ret;
4133           assert(*b == '\0', "fail in copy_expand_pid");
4134           if (p == src_end && b == buf_end + 1) {
4135             // reach the end of the buffer.
4136             return true;
4137           }
4138         }
4139         p++;
4140         break;
4141       }
4142       default :
4143         *b++ = '%';
4144       }
4145     } else {
4146       *b++ = *p++;
4147     }
4148   }
4149   *b = '\0';
4150   return (p == src_end); // return false if not all of the source was copied
4151 }