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