1 /*
   2  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/classLoader.hpp"
  27 #include "classfile/javaAssertions.hpp"
  28 #include "classfile/moduleEntry.hpp"
  29 #include "classfile/stringTable.hpp"
  30 #include "classfile/symbolTable.hpp"
  31 #include "gc/shared/cardTableRS.hpp"
  32 #include "gc/shared/genCollectedHeap.hpp"
  33 #include "gc/shared/referenceProcessor.hpp"
  34 #include "gc/shared/taskqueue.hpp"
  35 #include "logging/log.hpp"
  36 #include "logging/logConfiguration.hpp"
  37 #include "logging/logStream.hpp"
  38 #include "logging/logTag.hpp"
  39 #include "memory/allocation.inline.hpp"
  40 #include "memory/universe.inline.hpp"
  41 #include "oops/oop.inline.hpp"
  42 #include "prims/jvm.h"
  43 #include "prims/jvmtiExport.hpp"
  44 #include "runtime/arguments.hpp"
  45 #include "runtime/arguments_ext.hpp"
  46 #include "runtime/commandLineFlagConstraintList.hpp"
  47 #include "runtime/commandLineFlagWriteableList.hpp"
  48 #include "runtime/commandLineFlagRangeList.hpp"
  49 #include "runtime/globals.hpp"
  50 #include "runtime/globals_extension.hpp"
  51 #include "runtime/java.hpp"
  52 #include "runtime/os.hpp"
  53 #include "runtime/vm_version.hpp"
  54 #include "services/management.hpp"
  55 #include "services/memTracker.hpp"
  56 #include "utilities/align.hpp"
  57 #include "utilities/defaultStream.hpp"
  58 #include "utilities/macros.hpp"
  59 #include "utilities/stringUtils.hpp"
  60 #if INCLUDE_JVMCI
  61 #include "jvmci/jvmciRuntime.hpp"
  62 #endif
  63 #if INCLUDE_ALL_GCS
  64 #include "gc/cms/compactibleFreeListSpace.hpp"
  65 #include "gc/g1/g1CollectedHeap.inline.hpp"
  66 #include "gc/parallel/parallelScavengeHeap.hpp"
  67 #endif // INCLUDE_ALL_GCS
  68 
  69 // Note: This is a special bug reporting site for the JVM
  70 #define DEFAULT_VENDOR_URL_BUG "http://bugreport.java.com/bugreport/crash.jsp"
  71 #define DEFAULT_JAVA_LAUNCHER  "generic"
  72 
  73 char*  Arguments::_jvm_flags_file               = NULL;
  74 char** Arguments::_jvm_flags_array              = NULL;
  75 int    Arguments::_num_jvm_flags                = 0;
  76 char** Arguments::_jvm_args_array               = NULL;
  77 int    Arguments::_num_jvm_args                 = 0;
  78 char*  Arguments::_java_command                 = NULL;
  79 SystemProperty* Arguments::_system_properties   = NULL;
  80 const char*  Arguments::_gc_log_filename        = NULL;
  81 size_t Arguments::_conservative_max_heap_alignment = 0;
  82 size_t Arguments::_min_heap_size                = 0;
  83 Arguments::Mode Arguments::_mode                = _mixed;
  84 bool   Arguments::_java_compiler                = false;
  85 bool   Arguments::_xdebug_mode                  = false;
  86 const char*  Arguments::_java_vendor_url_bug    = DEFAULT_VENDOR_URL_BUG;
  87 const char*  Arguments::_sun_java_launcher      = DEFAULT_JAVA_LAUNCHER;
  88 int    Arguments::_sun_java_launcher_pid        = -1;
  89 bool   Arguments::_sun_java_launcher_is_altjvm  = false;
  90 
  91 // These parameters are reset in method parse_vm_init_args()
  92 bool   Arguments::_AlwaysCompileLoopMethods     = AlwaysCompileLoopMethods;
  93 bool   Arguments::_UseOnStackReplacement        = UseOnStackReplacement;
  94 bool   Arguments::_BackgroundCompilation        = BackgroundCompilation;
  95 bool   Arguments::_ClipInlining                 = ClipInlining;
  96 intx   Arguments::_Tier3InvokeNotifyFreqLog     = Tier3InvokeNotifyFreqLog;
  97 intx   Arguments::_Tier4InvocationThreshold     = Tier4InvocationThreshold;
  98 
  99 char*  Arguments::SharedArchivePath             = NULL;
 100 
 101 AgentLibraryList Arguments::_libraryList;
 102 AgentLibraryList Arguments::_agentList;
 103 
 104 abort_hook_t     Arguments::_abort_hook         = NULL;
 105 exit_hook_t      Arguments::_exit_hook          = NULL;
 106 vfprintf_hook_t  Arguments::_vfprintf_hook      = NULL;
 107 
 108 
 109 SystemProperty *Arguments::_sun_boot_library_path = NULL;
 110 SystemProperty *Arguments::_java_library_path = NULL;
 111 SystemProperty *Arguments::_java_home = NULL;
 112 SystemProperty *Arguments::_java_class_path = NULL;
 113 SystemProperty *Arguments::_jdk_boot_class_path_append = NULL;
 114 
 115 GrowableArray<ModulePatchPath*> *Arguments::_patch_mod_prefix = NULL;
 116 PathString *Arguments::_system_boot_class_path = NULL;
 117 bool Arguments::_has_jimage = false;
 118 
 119 char* Arguments::_ext_dirs = NULL;
 120 
 121 // Check if head of 'option' matches 'name', and sets 'tail' to the remaining
 122 // part of the option string.
 123 static bool match_option(const JavaVMOption *option, const char* name,
 124                          const char** tail) {
 125   size_t len = strlen(name);
 126   if (strncmp(option->optionString, name, len) == 0) {
 127     *tail = option->optionString + len;
 128     return true;
 129   } else {
 130     return false;
 131   }
 132 }
 133 
 134 // Check if 'option' matches 'name'. No "tail" is allowed.
 135 static bool match_option(const JavaVMOption *option, const char* name) {
 136   const char* tail = NULL;
 137   bool result = match_option(option, name, &tail);
 138   if (tail != NULL && *tail == '\0') {
 139     return result;
 140   } else {
 141     return false;
 142   }
 143 }
 144 
 145 // Return true if any of the strings in null-terminated array 'names' matches.
 146 // If tail_allowed is true, then the tail must begin with a colon; otherwise,
 147 // the option must match exactly.
 148 static bool match_option(const JavaVMOption* option, const char** names, const char** tail,
 149   bool tail_allowed) {
 150   for (/* empty */; *names != NULL; ++names) {
 151   if (match_option(option, *names, tail)) {
 152       if (**tail == '\0' || (tail_allowed && **tail == ':')) {
 153         return true;
 154       }
 155     }
 156   }
 157   return false;
 158 }
 159 
 160 static void logOption(const char* opt) {
 161   if (PrintVMOptions) {
 162     jio_fprintf(defaultStream::output_stream(), "VM option '%s'\n", opt);
 163   }
 164 }
 165 
 166 bool needs_module_property_warning = false;
 167 
 168 #define MODULE_PROPERTY_PREFIX "jdk.module."
 169 #define MODULE_PROPERTY_PREFIX_LEN 11
 170 #define ADDEXPORTS "addexports"
 171 #define ADDEXPORTS_LEN 10
 172 #define ADDREADS "addreads"
 173 #define ADDREADS_LEN 8
 174 #define ADDOPENS "addopens"
 175 #define ADDOPENS_LEN 8
 176 #define PATCH "patch"
 177 #define PATCH_LEN 5
 178 #define ADDMODS "addmods"
 179 #define ADDMODS_LEN 7
 180 #define LIMITMODS "limitmods"
 181 #define LIMITMODS_LEN 9
 182 #define PATH "path"
 183 #define PATH_LEN 4
 184 #define UPGRADE_PATH "upgrade.path"
 185 #define UPGRADE_PATH_LEN 12
 186 
 187 // Return TRUE if option matches 'property', or 'property=', or 'property.'.
 188 static bool matches_property_suffix(const char* option, const char* property, size_t len) {
 189   return ((strncmp(option, property, len) == 0) &&
 190           (option[len] == '=' || option[len] == '.' || option[len] == '\0'));
 191 }
 192 
 193 // Return true if property starts with "jdk.module." and its ensuing chars match
 194 // any of the reserved module properties.
 195 // property should be passed without the leading "-D".
 196 bool Arguments::is_internal_module_property(const char* property) {
 197   assert((strncmp(property, "-D", 2) != 0), "Unexpected leading -D");
 198   if  (strncmp(property, MODULE_PROPERTY_PREFIX, MODULE_PROPERTY_PREFIX_LEN) == 0) {
 199     const char* property_suffix = property + MODULE_PROPERTY_PREFIX_LEN;
 200     if (matches_property_suffix(property_suffix, ADDEXPORTS, ADDEXPORTS_LEN) ||
 201         matches_property_suffix(property_suffix, ADDREADS, ADDREADS_LEN) ||
 202         matches_property_suffix(property_suffix, ADDOPENS, ADDOPENS_LEN) ||
 203         matches_property_suffix(property_suffix, PATCH, PATCH_LEN) ||
 204         matches_property_suffix(property_suffix, ADDMODS, ADDMODS_LEN) ||
 205         matches_property_suffix(property_suffix, LIMITMODS, LIMITMODS_LEN) ||
 206         matches_property_suffix(property_suffix, PATH, PATH_LEN) ||
 207         matches_property_suffix(property_suffix, UPGRADE_PATH, UPGRADE_PATH_LEN)) {
 208       return true;
 209     }
 210   }
 211   return false;
 212 }
 213 
 214 // Process java launcher properties.
 215 void Arguments::process_sun_java_launcher_properties(JavaVMInitArgs* args) {
 216   // See if sun.java.launcher, sun.java.launcher.is_altjvm or
 217   // sun.java.launcher.pid is defined.
 218   // Must do this before setting up other system properties,
 219   // as some of them may depend on launcher type.
 220   for (int index = 0; index < args->nOptions; index++) {
 221     const JavaVMOption* option = args->options + index;
 222     const char* tail;
 223 
 224     if (match_option(option, "-Dsun.java.launcher=", &tail)) {
 225       process_java_launcher_argument(tail, option->extraInfo);
 226       continue;
 227     }
 228     if (match_option(option, "-Dsun.java.launcher.is_altjvm=", &tail)) {
 229       if (strcmp(tail, "true") == 0) {
 230         _sun_java_launcher_is_altjvm = true;
 231       }
 232       continue;
 233     }
 234     if (match_option(option, "-Dsun.java.launcher.pid=", &tail)) {
 235       _sun_java_launcher_pid = atoi(tail);
 236       continue;
 237     }
 238   }
 239 }
 240 
 241 // Initialize system properties key and value.
 242 void Arguments::init_system_properties() {
 243 
 244   // Set up _system_boot_class_path which is not a property but
 245   // relies heavily on argument processing and the jdk.boot.class.path.append
 246   // property. It is used to store the underlying system boot class path.
 247   _system_boot_class_path = new PathString(NULL);
 248 
 249   PropertyList_add(&_system_properties, new SystemProperty("java.vm.specification.name",
 250                                                            "Java Virtual Machine Specification",  false));
 251   PropertyList_add(&_system_properties, new SystemProperty("java.vm.version", VM_Version::vm_release(),  false));
 252   PropertyList_add(&_system_properties, new SystemProperty("java.vm.name", VM_Version::vm_name(),  false));
 253   PropertyList_add(&_system_properties, new SystemProperty("java.vm.info", VM_Version::vm_info_string(),  true));
 254   PropertyList_add(&_system_properties, new SystemProperty("jdk.debug", VM_Version::jdk_debug_level(),  false));
 255 
 256   // Following are JVMTI agent writable properties.
 257   // Properties values are set to NULL and they are
 258   // os specific they are initialized in os::init_system_properties_values().
 259   _sun_boot_library_path = new SystemProperty("sun.boot.library.path", NULL,  true);
 260   _java_library_path = new SystemProperty("java.library.path", NULL,  true);
 261   _java_home =  new SystemProperty("java.home", NULL,  true);
 262   _java_class_path = new SystemProperty("java.class.path", "",  true);
 263   // jdk.boot.class.path.append is a non-writeable, internal property.
 264   // It can only be set by either:
 265   //    - -Xbootclasspath/a:
 266   //    - AddToBootstrapClassLoaderSearch during JVMTI OnLoad phase
 267   _jdk_boot_class_path_append = new SystemProperty("jdk.boot.class.path.append", "", false, true);
 268 
 269   // Add to System Property list.
 270   PropertyList_add(&_system_properties, _sun_boot_library_path);
 271   PropertyList_add(&_system_properties, _java_library_path);
 272   PropertyList_add(&_system_properties, _java_home);
 273   PropertyList_add(&_system_properties, _java_class_path);
 274   PropertyList_add(&_system_properties, _jdk_boot_class_path_append);
 275 
 276   // Set OS specific system properties values
 277   os::init_system_properties_values();
 278 }
 279 
 280 // Update/Initialize System properties after JDK version number is known
 281 void Arguments::init_version_specific_system_properties() {
 282   enum { bufsz = 16 };
 283   char buffer[bufsz];
 284   const char* spec_vendor = "Oracle Corporation";
 285   uint32_t spec_version = JDK_Version::current().major_version();
 286 
 287   jio_snprintf(buffer, bufsz, UINT32_FORMAT, spec_version);
 288 
 289   PropertyList_add(&_system_properties,
 290       new SystemProperty("java.vm.specification.vendor",  spec_vendor, false));
 291   PropertyList_add(&_system_properties,
 292       new SystemProperty("java.vm.specification.version", buffer, false));
 293   PropertyList_add(&_system_properties,
 294       new SystemProperty("java.vm.vendor", VM_Version::vm_vendor(),  false));
 295 }
 296 
 297 /*
 298  *  -XX argument processing:
 299  *
 300  *  -XX arguments are defined in several places, such as:
 301  *      globals.hpp, globals_<cpu>.hpp, globals_<os>.hpp, <compiler>_globals.hpp, or <gc>_globals.hpp.
 302  *  -XX arguments are parsed in parse_argument().
 303  *  -XX argument bounds checking is done in check_vm_args_consistency().
 304  *
 305  * Over time -XX arguments may change. There are mechanisms to handle common cases:
 306  *
 307  *      ALIASED: An option that is simply another name for another option. This is often
 308  *               part of the process of deprecating a flag, but not all aliases need
 309  *               to be deprecated.
 310  *
 311  *               Create an alias for an option by adding the old and new option names to the
 312  *               "aliased_jvm_flags" table. Delete the old variable from globals.hpp (etc).
 313  *
 314  *   DEPRECATED: An option that is supported, but a warning is printed to let the user know that
 315  *               support may be removed in the future. Both regular and aliased options may be
 316  *               deprecated.
 317  *
 318  *               Add a deprecation warning for an option (or alias) by adding an entry in the
 319  *               "special_jvm_flags" table and setting the "deprecated_in" field.
 320  *               Often an option "deprecated" in one major release will
 321  *               be made "obsolete" in the next. In this case the entry should also have its
 322  *               "obsolete_in" field set.
 323  *
 324  *     OBSOLETE: An option that has been removed (and deleted from globals.hpp), but is still accepted
 325  *               on the command line. A warning is printed to let the user know that option might not
 326  *               be accepted in the future.
 327  *
 328  *               Add an obsolete warning for an option by adding an entry in the "special_jvm_flags"
 329  *               table and setting the "obsolete_in" field.
 330  *
 331  *      EXPIRED: A deprecated or obsolete option that has an "accept_until" version less than or equal
 332  *               to the current JDK version. The system will flatly refuse to admit the existence of
 333  *               the flag. This allows a flag to die automatically over JDK releases.
 334  *
 335  *               Note that manual cleanup of expired options should be done at major JDK version upgrades:
 336  *                  - Newly expired options should be removed from the special_jvm_flags and aliased_jvm_flags tables.
 337  *                  - Newly obsolete or expired deprecated options should have their global variable
 338  *                    definitions removed (from globals.hpp, etc) and related implementations removed.
 339  *
 340  * Recommended approach for removing options:
 341  *
 342  * To remove options commonly used by customers (e.g. product, commercial -XX options), use
 343  * the 3-step model adding major release numbers to the deprecate, obsolete and expire columns.
 344  *
 345  * To remove internal options (e.g. diagnostic, experimental, develop options), use
 346  * a 2-step model adding major release numbers to the obsolete and expire columns.
 347  *
 348  * To change the name of an option, use the alias table as well as a 2-step
 349  * model adding major release numbers to the deprecate and expire columns.
 350  * Think twice about aliasing commonly used customer options.
 351  *
 352  * There are times when it is appropriate to leave a future release number as undefined.
 353  *
 354  * Tests:  Aliases should be tested in VMAliasOptions.java.
 355  *         Deprecated options should be tested in VMDeprecatedOptions.java.
 356  */
 357 
 358 // The special_jvm_flags table declares options that are being deprecated and/or obsoleted. The
 359 // "deprecated_in" or "obsolete_in" fields may be set to "undefined", but not both.
 360 // When the JDK version reaches 'deprecated_in' limit, the JVM will process this flag on
 361 // the command-line as usual, but will issue a warning.
 362 // When the JDK version reaches 'obsolete_in' limit, the JVM will continue accepting this flag on
 363 // the command-line, while issuing a warning and ignoring the flag value.
 364 // Once the JDK version reaches 'expired_in' limit, the JVM will flatly refuse to admit the
 365 // existence of the flag.
 366 //
 367 // MANUAL CLEANUP ON JDK VERSION UPDATES:
 368 // This table ensures that the handling of options will update automatically when the JDK
 369 // version is incremented, but the source code needs to be cleanup up manually:
 370 // - As "deprecated" options age into "obsolete" or "expired" options, the associated "globals"
 371 //   variable should be removed, as well as users of the variable.
 372 // - As "deprecated" options age into "obsolete" options, move the entry into the
 373 //   "Obsolete Flags" section of the table.
 374 // - All expired options should be removed from the table.
 375 static SpecialFlag const special_jvm_flags[] = {
 376   // -------------- Deprecated Flags --------------
 377   // --- Non-alias flags - sorted by obsolete_in then expired_in:
 378   { "MaxGCMinorPauseMillis",        JDK_Version::jdk(8), JDK_Version::undefined(), JDK_Version::undefined() },
 379   { "UseConcMarkSweepGC",           JDK_Version::jdk(9), JDK_Version::undefined(), JDK_Version::undefined() },
 380   { "MonitorInUseLists",            JDK_Version::jdk(10),JDK_Version::undefined(), JDK_Version::undefined() },
 381   { "MaxRAMFraction",               JDK_Version::jdk(10),  JDK_Version::undefined(), JDK_Version::undefined() },
 382   { "MinRAMFraction",               JDK_Version::jdk(10),  JDK_Version::undefined(), JDK_Version::undefined() },
 383   { "InitialRAMFraction",           JDK_Version::jdk(10),  JDK_Version::undefined(), JDK_Version::undefined() },
 384 
 385   // --- Deprecated alias flags (see also aliased_jvm_flags) - sorted by obsolete_in then expired_in:
 386   { "DefaultMaxRAMFraction",        JDK_Version::jdk(8),  JDK_Version::undefined(), JDK_Version::undefined() },
 387   { "CreateMinidumpOnCrash",        JDK_Version::jdk(9),  JDK_Version::undefined(), JDK_Version::undefined() },
 388   { "MustCallLoadClassInternal",    JDK_Version::jdk(10), JDK_Version::undefined(), JDK_Version::undefined() },
 389   { "UnsyncloadClass",              JDK_Version::jdk(10), JDK_Version::undefined(), JDK_Version::undefined() },
 390 
 391   // -------------- Obsolete Flags - sorted by expired_in --------------
 392   { "ConvertSleepToYield",           JDK_Version::jdk(9),      JDK_Version::jdk(10), JDK_Version::jdk(11) },
 393   { "ConvertYieldToSleep",           JDK_Version::jdk(9),      JDK_Version::jdk(10), JDK_Version::jdk(11) },
 394   { "MinSleepInterval",              JDK_Version::jdk(9),      JDK_Version::jdk(10), JDK_Version::jdk(11) },
 395   { "PermSize",                      JDK_Version::undefined(), JDK_Version::jdk(8),  JDK_Version::undefined() },
 396   { "MaxPermSize",                   JDK_Version::undefined(), JDK_Version::jdk(8),  JDK_Version::undefined() },
 397 
 398 #ifdef TEST_VERIFY_SPECIAL_JVM_FLAGS
 399   { "dep > obs",                    JDK_Version::jdk(9), JDK_Version::jdk(8), JDK_Version::undefined() },
 400   { "dep > exp ",                   JDK_Version::jdk(9), JDK_Version::undefined(), JDK_Version::jdk(8) },
 401   { "obs > exp ",                   JDK_Version::undefined(), JDK_Version::jdk(9), JDK_Version::jdk(8) },
 402   { "not deprecated or obsolete",   JDK_Version::undefined(), JDK_Version::undefined(), JDK_Version::jdk(9) },
 403   { "dup option",                   JDK_Version::jdk(9), JDK_Version::undefined(), JDK_Version::undefined() },
 404   { "dup option",                   JDK_Version::jdk(9), JDK_Version::undefined(), JDK_Version::undefined() },
 405   { "BytecodeVerificationRemote",   JDK_Version::undefined(), JDK_Version::jdk(9), JDK_Version::undefined() },
 406 #endif
 407 
 408   { NULL, JDK_Version(0), JDK_Version(0) }
 409 };
 410 
 411 // Flags that are aliases for other flags.
 412 typedef struct {
 413   const char* alias_name;
 414   const char* real_name;
 415 } AliasedFlag;
 416 
 417 static AliasedFlag const aliased_jvm_flags[] = {
 418   { "DefaultMaxRAMFraction",    "MaxRAMFraction"    },
 419   { "CreateMinidumpOnCrash",    "CreateCoredumpOnCrash" },
 420   { NULL, NULL}
 421 };
 422 
 423 // NOTE: A compatibility request will be necessary for each alias to be removed.
 424 static AliasedLoggingFlag const aliased_logging_flags[] = {
 425   { "PrintCompressedOopsMode",   LogLevel::Info,  true,  LOG_TAGS(gc, heap, coops) },
 426   { "PrintSharedSpaces",         LogLevel::Info,  true,  LOG_TAGS(cds) },
 427   { "TraceBiasedLocking",        LogLevel::Info,  true,  LOG_TAGS(biasedlocking) },
 428   { "TraceClassLoading",         LogLevel::Info,  true,  LOG_TAGS(class, load) },
 429   { "TraceClassLoadingPreorder", LogLevel::Debug, true,  LOG_TAGS(class, preorder) },
 430   { "TraceClassPaths",           LogLevel::Info,  true,  LOG_TAGS(class, path) },
 431   { "TraceClassResolution",      LogLevel::Debug, true,  LOG_TAGS(class, resolve) },
 432   { "TraceClassUnloading",       LogLevel::Info,  true,  LOG_TAGS(class, unload) },
 433   { "TraceExceptions",           LogLevel::Info,  true,  LOG_TAGS(exceptions) },
 434   { "TraceLoaderConstraints",    LogLevel::Info,  true,  LOG_TAGS(class, loader, constraints) },
 435   { "TraceMonitorInflation",     LogLevel::Debug, true,  LOG_TAGS(monitorinflation) },
 436   { "TraceSafepointCleanupTime", LogLevel::Info,  true,  LOG_TAGS(safepoint, cleanup) },
 437   { "TraceJVMTIObjectTagging",   LogLevel::Debug, true,  LOG_TAGS(jvmti, objecttagging) },
 438   { "TraceRedefineClasses",      LogLevel::Info,  false, LOG_TAGS(redefine, class) },
 439   { NULL,                        LogLevel::Off,   false, LOG_TAGS(_NO_TAG) }
 440 };
 441 
 442 #ifndef PRODUCT
 443 // These options are removed in jdk9. Remove this code for jdk10.
 444 static AliasedFlag const removed_develop_logging_flags[] = {
 445   { "TraceClassInitialization",   "-Xlog:class+init" },
 446   { "TraceClassLoaderData",       "-Xlog:class+loader+data" },
 447   { "TraceDefaultMethods",        "-Xlog:defaultmethods=debug" },
 448   { "TraceItables",               "-Xlog:itables=debug" },
 449   { "TraceMonitorMismatch",       "-Xlog:monitormismatch=info" },
 450   { "TraceSafepoint",             "-Xlog:safepoint=debug" },
 451   { "TraceStartupTime",           "-Xlog:startuptime" },
 452   { "TraceVMOperation",           "-Xlog:vmoperation=debug" },
 453   { "PrintVtables",               "-Xlog:vtables=debug" },
 454   { "VerboseVerification",        "-Xlog:verification" },
 455   { NULL, NULL }
 456 };
 457 #endif //PRODUCT
 458 
 459 // Return true if "v" is less than "other", where "other" may be "undefined".
 460 static bool version_less_than(JDK_Version v, JDK_Version other) {
 461   assert(!v.is_undefined(), "must be defined");
 462   if (!other.is_undefined() && v.compare(other) >= 0) {
 463     return false;
 464   } else {
 465     return true;
 466   }
 467 }
 468 
 469 extern bool lookup_special_flag_ext(const char *flag_name, SpecialFlag& flag);
 470 
 471 static bool lookup_special_flag(const char *flag_name, SpecialFlag& flag) {
 472   // Allow extensions to have priority
 473   if (lookup_special_flag_ext(flag_name, flag)) {
 474     return true;
 475   }
 476 
 477   for (size_t i = 0; special_jvm_flags[i].name != NULL; i++) {
 478     if ((strcmp(special_jvm_flags[i].name, flag_name) == 0)) {
 479       flag = special_jvm_flags[i];
 480       return true;
 481     }
 482   }
 483   return false;
 484 }
 485 
 486 bool Arguments::is_obsolete_flag(const char *flag_name, JDK_Version* version) {
 487   assert(version != NULL, "Must provide a version buffer");
 488   SpecialFlag flag;
 489   if (lookup_special_flag(flag_name, flag)) {
 490     if (!flag.obsolete_in.is_undefined()) {
 491       if (version_less_than(JDK_Version::current(), flag.expired_in)) {
 492         *version = flag.obsolete_in;
 493         return true;
 494       }
 495     }
 496   }
 497   return false;
 498 }
 499 
 500 int Arguments::is_deprecated_flag(const char *flag_name, JDK_Version* version) {
 501   assert(version != NULL, "Must provide a version buffer");
 502   SpecialFlag flag;
 503   if (lookup_special_flag(flag_name, flag)) {
 504     if (!flag.deprecated_in.is_undefined()) {
 505       if (version_less_than(JDK_Version::current(), flag.obsolete_in) &&
 506           version_less_than(JDK_Version::current(), flag.expired_in)) {
 507         *version = flag.deprecated_in;
 508         return 1;
 509       } else {
 510         return -1;
 511       }
 512     }
 513   }
 514   return 0;
 515 }
 516 
 517 #ifndef PRODUCT
 518 const char* Arguments::removed_develop_logging_flag_name(const char* name){
 519   for (size_t i = 0; removed_develop_logging_flags[i].alias_name != NULL; i++) {
 520     const AliasedFlag& flag = removed_develop_logging_flags[i];
 521     if (strcmp(flag.alias_name, name) == 0) {
 522       return flag.real_name;
 523     }
 524   }
 525   return NULL;
 526 }
 527 #endif // PRODUCT
 528 
 529 const char* Arguments::real_flag_name(const char *flag_name) {
 530   for (size_t i = 0; aliased_jvm_flags[i].alias_name != NULL; i++) {
 531     const AliasedFlag& flag_status = aliased_jvm_flags[i];
 532     if (strcmp(flag_status.alias_name, flag_name) == 0) {
 533         return flag_status.real_name;
 534     }
 535   }
 536   return flag_name;
 537 }
 538 
 539 #ifdef ASSERT
 540 static bool lookup_special_flag(const char *flag_name, size_t skip_index) {
 541   for (size_t i = 0; special_jvm_flags[i].name != NULL; i++) {
 542     if ((i != skip_index) && (strcmp(special_jvm_flags[i].name, flag_name) == 0)) {
 543       return true;
 544     }
 545   }
 546   return false;
 547 }
 548 
 549 static bool verify_special_jvm_flags() {
 550   bool success = true;
 551   for (size_t i = 0; special_jvm_flags[i].name != NULL; i++) {
 552     const SpecialFlag& flag = special_jvm_flags[i];
 553     if (lookup_special_flag(flag.name, i)) {
 554       warning("Duplicate special flag declaration \"%s\"", flag.name);
 555       success = false;
 556     }
 557     if (flag.deprecated_in.is_undefined() &&
 558         flag.obsolete_in.is_undefined()) {
 559       warning("Special flag entry \"%s\" must declare version deprecated and/or obsoleted in.", flag.name);
 560       success = false;
 561     }
 562 
 563     if (!flag.deprecated_in.is_undefined()) {
 564       if (!version_less_than(flag.deprecated_in, flag.obsolete_in)) {
 565         warning("Special flag entry \"%s\" must be deprecated before obsoleted.", flag.name);
 566         success = false;
 567       }
 568 
 569       if (!version_less_than(flag.deprecated_in, flag.expired_in)) {
 570         warning("Special flag entry \"%s\" must be deprecated before expired.", flag.name);
 571         success = false;
 572       }
 573     }
 574 
 575     if (!flag.obsolete_in.is_undefined()) {
 576       if (!version_less_than(flag.obsolete_in, flag.expired_in)) {
 577         warning("Special flag entry \"%s\" must be obsoleted before expired.", flag.name);
 578         success = false;
 579       }
 580 
 581       // if flag has become obsolete it should not have a "globals" flag defined anymore.
 582       if (!version_less_than(JDK_Version::current(), flag.obsolete_in)) {
 583         if (Flag::find_flag(flag.name) != NULL) {
 584           warning("Global variable for obsolete special flag entry \"%s\" should be removed", flag.name);
 585           success = false;
 586         }
 587       }
 588     }
 589 
 590     if (!flag.expired_in.is_undefined()) {
 591       // if flag has become expired it should not have a "globals" flag defined anymore.
 592       if (!version_less_than(JDK_Version::current(), flag.expired_in)) {
 593         if (Flag::find_flag(flag.name) != NULL) {
 594           warning("Global variable for expired flag entry \"%s\" should be removed", flag.name);
 595           success = false;
 596         }
 597       }
 598     }
 599 
 600   }
 601   return success;
 602 }
 603 #endif
 604 
 605 // Parses a size specification string.
 606 bool Arguments::atojulong(const char *s, julong* result) {
 607   julong n = 0;
 608 
 609   // First char must be a digit. Don't allow negative numbers or leading spaces.
 610   if (!isdigit(*s)) {
 611     return false;
 612   }
 613 
 614   bool is_hex = (s[0] == '0' && (s[1] == 'x' || s[1] == 'X'));
 615   char* remainder;
 616   errno = 0;
 617   n = strtoull(s, &remainder, (is_hex ? 16 : 10));
 618   if (errno != 0) {
 619     return false;
 620   }
 621 
 622   // Fail if no number was read at all or if the remainder contains more than a single non-digit character.
 623   if (remainder == s || strlen(remainder) > 1) {
 624     return false;
 625   }
 626 
 627   switch (*remainder) {
 628     case 'T': case 't':
 629       *result = n * G * K;
 630       // Check for overflow.
 631       if (*result/((julong)G * K) != n) return false;
 632       return true;
 633     case 'G': case 'g':
 634       *result = n * G;
 635       if (*result/G != n) return false;
 636       return true;
 637     case 'M': case 'm':
 638       *result = n * M;
 639       if (*result/M != n) return false;
 640       return true;
 641     case 'K': case 'k':
 642       *result = n * K;
 643       if (*result/K != n) return false;
 644       return true;
 645     case '\0':
 646       *result = n;
 647       return true;
 648     default:
 649       return false;
 650   }
 651 }
 652 
 653 Arguments::ArgsRange Arguments::check_memory_size(julong size, julong min_size, julong max_size) {
 654   if (size < min_size) return arg_too_small;
 655   if (size > max_size) return arg_too_big;
 656   return arg_in_range;
 657 }
 658 
 659 // Describe an argument out of range error
 660 void Arguments::describe_range_error(ArgsRange errcode) {
 661   switch(errcode) {
 662   case arg_too_big:
 663     jio_fprintf(defaultStream::error_stream(),
 664                 "The specified size exceeds the maximum "
 665                 "representable size.\n");
 666     break;
 667   case arg_too_small:
 668   case arg_unreadable:
 669   case arg_in_range:
 670     // do nothing for now
 671     break;
 672   default:
 673     ShouldNotReachHere();
 674   }
 675 }
 676 
 677 static bool set_bool_flag(const char* name, bool value, Flag::Flags origin) {
 678   if (CommandLineFlags::boolAtPut(name, &value, origin) == Flag::SUCCESS) {
 679     return true;
 680   } else {
 681     return false;
 682   }
 683 }
 684 
 685 static bool set_fp_numeric_flag(const char* name, char* value, Flag::Flags origin) {
 686   char* end;
 687   errno = 0;
 688   double v = strtod(value, &end);
 689   if ((errno != 0) || (*end != 0)) {
 690     return false;
 691   }
 692 
 693   if (CommandLineFlags::doubleAtPut(name, &v, origin) == Flag::SUCCESS) {
 694     return true;
 695   }
 696   return false;
 697 }
 698 
 699 static bool set_numeric_flag(const char* name, char* value, Flag::Flags origin) {
 700   julong v;
 701   int int_v;
 702   intx intx_v;
 703   bool is_neg = false;
 704   Flag* result = Flag::find_flag(name, strlen(name));
 705 
 706   if (result == NULL) {
 707     return false;
 708   }
 709 
 710   // Check the sign first since atojulong() parses only unsigned values.
 711   if (*value == '-') {
 712     if (!result->is_intx() && !result->is_int()) {
 713       return false;
 714     }
 715     value++;
 716     is_neg = true;
 717   }
 718   if (!Arguments::atojulong(value, &v)) {
 719     return false;
 720   }
 721   if (result->is_int()) {
 722     int_v = (int) v;
 723     if (is_neg) {
 724       int_v = -int_v;
 725     }
 726     return CommandLineFlags::intAtPut(result, &int_v, origin) == Flag::SUCCESS;
 727   } else if (result->is_uint()) {
 728     uint uint_v = (uint) v;
 729     return CommandLineFlags::uintAtPut(result, &uint_v, origin) == Flag::SUCCESS;
 730   } else if (result->is_intx()) {
 731     intx_v = (intx) v;
 732     if (is_neg) {
 733       intx_v = -intx_v;
 734     }
 735     return CommandLineFlags::intxAtPut(result, &intx_v, origin) == Flag::SUCCESS;
 736   } else if (result->is_uintx()) {
 737     uintx uintx_v = (uintx) v;
 738     return CommandLineFlags::uintxAtPut(result, &uintx_v, origin) == Flag::SUCCESS;
 739   } else if (result->is_uint64_t()) {
 740     uint64_t uint64_t_v = (uint64_t) v;
 741     return CommandLineFlags::uint64_tAtPut(result, &uint64_t_v, origin) == Flag::SUCCESS;
 742   } else if (result->is_size_t()) {
 743     size_t size_t_v = (size_t) v;
 744     return CommandLineFlags::size_tAtPut(result, &size_t_v, origin) == Flag::SUCCESS;
 745   } else if (result->is_double()) {
 746     double double_v = (double) v;
 747     return CommandLineFlags::doubleAtPut(result, &double_v, origin) == Flag::SUCCESS;
 748   } else {
 749     return false;
 750   }
 751 }
 752 
 753 static bool set_string_flag(const char* name, const char* value, Flag::Flags origin) {
 754   if (CommandLineFlags::ccstrAtPut(name, &value, origin) != Flag::SUCCESS) return false;
 755   // Contract:  CommandLineFlags always returns a pointer that needs freeing.
 756   FREE_C_HEAP_ARRAY(char, value);
 757   return true;
 758 }
 759 
 760 static bool append_to_string_flag(const char* name, const char* new_value, Flag::Flags origin) {
 761   const char* old_value = "";
 762   if (CommandLineFlags::ccstrAt(name, &old_value) != Flag::SUCCESS) return false;
 763   size_t old_len = old_value != NULL ? strlen(old_value) : 0;
 764   size_t new_len = strlen(new_value);
 765   const char* value;
 766   char* free_this_too = NULL;
 767   if (old_len == 0) {
 768     value = new_value;
 769   } else if (new_len == 0) {
 770     value = old_value;
 771   } else {
 772      size_t length = old_len + 1 + new_len + 1;
 773      char* buf = NEW_C_HEAP_ARRAY(char, length, mtArguments);
 774     // each new setting adds another LINE to the switch:
 775     jio_snprintf(buf, length, "%s\n%s", old_value, new_value);
 776     value = buf;
 777     free_this_too = buf;
 778   }
 779   (void) CommandLineFlags::ccstrAtPut(name, &value, origin);
 780   // CommandLineFlags always returns a pointer that needs freeing.
 781   FREE_C_HEAP_ARRAY(char, value);
 782   if (free_this_too != NULL) {
 783     // CommandLineFlags made its own copy, so I must delete my own temp. buffer.
 784     FREE_C_HEAP_ARRAY(char, free_this_too);
 785   }
 786   return true;
 787 }
 788 
 789 const char* Arguments::handle_aliases_and_deprecation(const char* arg, bool warn) {
 790   const char* real_name = real_flag_name(arg);
 791   JDK_Version since = JDK_Version();
 792   switch (is_deprecated_flag(arg, &since)) {
 793     case -1:
 794       return NULL; // obsolete or expired, don't process normally
 795     case 0:
 796       return real_name;
 797     case 1: {
 798       if (warn) {
 799         char version[256];
 800         since.to_string(version, sizeof(version));
 801         if (real_name != arg) {
 802           warning("Option %s was deprecated in version %s and will likely be removed in a future release. Use option %s instead.",
 803                   arg, version, real_name);
 804         } else {
 805           warning("Option %s was deprecated in version %s and will likely be removed in a future release.",
 806                   arg, version);
 807         }
 808       }
 809       return real_name;
 810     }
 811   }
 812   ShouldNotReachHere();
 813   return NULL;
 814 }
 815 
 816 void log_deprecated_flag(const char* name, bool on, AliasedLoggingFlag alf) {
 817   LogTagType tagSet[] = {alf.tag0, alf.tag1, alf.tag2, alf.tag3, alf.tag4, alf.tag5};
 818   // Set tagset string buffer at max size of 256, large enough for any alias tagset
 819   const int max_tagset_size = 256;
 820   int max_tagset_len = max_tagset_size - 1;
 821   char tagset_buffer[max_tagset_size];
 822   tagset_buffer[0] = '\0';
 823 
 824   // Write tag-set for aliased logging option, in string list form
 825   int max_tags = sizeof(tagSet)/sizeof(tagSet[0]);
 826   for (int i = 0; i < max_tags && tagSet[i] != LogTag::__NO_TAG; i++) {
 827     if (i > 0) {
 828       strncat(tagset_buffer, "+", max_tagset_len - strlen(tagset_buffer));
 829     }
 830     strncat(tagset_buffer, LogTag::name(tagSet[i]), max_tagset_len - strlen(tagset_buffer));
 831   }
 832   if (!alf.exactMatch) {
 833       strncat(tagset_buffer, "*", max_tagset_len - strlen(tagset_buffer));
 834   }
 835   log_warning(arguments)("-XX:%s%s is deprecated. Will use -Xlog:%s=%s instead.",
 836                          (on) ? "+" : "-",
 837                          name,
 838                          tagset_buffer,
 839                          (on) ? LogLevel::name(alf.level) : "off");
 840 }
 841 
 842 AliasedLoggingFlag Arguments::catch_logging_aliases(const char* name, bool on){
 843   for (size_t i = 0; aliased_logging_flags[i].alias_name != NULL; i++) {
 844     const AliasedLoggingFlag& alf = aliased_logging_flags[i];
 845     if (strcmp(alf.alias_name, name) == 0) {
 846       log_deprecated_flag(name, on, alf);
 847       return alf;
 848     }
 849   }
 850   AliasedLoggingFlag a = {NULL, LogLevel::Off, false, LOG_TAGS(_NO_TAG)};
 851   return a;
 852 }
 853 
 854 bool Arguments::parse_argument(const char* arg, Flag::Flags origin) {
 855 
 856   // range of acceptable characters spelled out for portability reasons
 857 #define NAME_RANGE  "[abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_]"
 858 #define BUFLEN 255
 859   char name[BUFLEN+1];
 860   char dummy;
 861   const char* real_name;
 862   bool warn_if_deprecated = true;
 863 
 864   if (sscanf(arg, "-%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
 865     AliasedLoggingFlag alf = catch_logging_aliases(name, false);
 866     if (alf.alias_name != NULL){
 867       LogConfiguration::configure_stdout(LogLevel::Off, alf.exactMatch, alf.tag0, alf.tag1, alf.tag2, alf.tag3, alf.tag4, alf.tag5);
 868       return true;
 869     }
 870     real_name = handle_aliases_and_deprecation(name, warn_if_deprecated);
 871     if (real_name == NULL) {
 872       return false;
 873     }
 874     return set_bool_flag(real_name, false, origin);
 875   }
 876   if (sscanf(arg, "+%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
 877     AliasedLoggingFlag alf = catch_logging_aliases(name, true);
 878     if (alf.alias_name != NULL){
 879       LogConfiguration::configure_stdout(alf.level, alf.exactMatch, alf.tag0, alf.tag1, alf.tag2, alf.tag3, alf.tag4, alf.tag5);
 880       return true;
 881     }
 882     real_name = handle_aliases_and_deprecation(name, warn_if_deprecated);
 883     if (real_name == NULL) {
 884       return false;
 885     }
 886     return set_bool_flag(real_name, true, origin);
 887   }
 888 
 889   char punct;
 890   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "%c", name, &punct) == 2 && punct == '=') {
 891     const char* value = strchr(arg, '=') + 1;
 892     Flag* flag;
 893 
 894     // this scanf pattern matches both strings (handled here) and numbers (handled later))
 895     AliasedLoggingFlag alf = catch_logging_aliases(name, true);
 896     if (alf.alias_name != NULL) {
 897       LogConfiguration::configure_stdout(alf.level, alf.exactMatch, alf.tag0, alf.tag1, alf.tag2, alf.tag3, alf.tag4, alf.tag5);
 898       return true;
 899     }
 900     real_name = handle_aliases_and_deprecation(name, warn_if_deprecated);
 901     if (real_name == NULL) {
 902       return false;
 903     }
 904     flag = Flag::find_flag(real_name);
 905     if (flag != NULL && flag->is_ccstr()) {
 906       if (flag->ccstr_accumulates()) {
 907         return append_to_string_flag(real_name, value, origin);
 908       } else {
 909         if (value[0] == '\0') {
 910           value = NULL;
 911         }
 912         return set_string_flag(real_name, value, origin);
 913       }
 914     } else {
 915       warn_if_deprecated = false; // if arg is deprecated, we've already done warning...
 916     }
 917   }
 918 
 919   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE ":%c", name, &punct) == 2 && punct == '=') {
 920     const char* value = strchr(arg, '=') + 1;
 921     // -XX:Foo:=xxx will reset the string flag to the given value.
 922     if (value[0] == '\0') {
 923       value = NULL;
 924     }
 925     real_name = handle_aliases_and_deprecation(name, warn_if_deprecated);
 926     if (real_name == NULL) {
 927       return false;
 928     }
 929     return set_string_flag(real_name, value, origin);
 930   }
 931 
 932 #define SIGNED_FP_NUMBER_RANGE "[-0123456789.eE+]"
 933 #define SIGNED_NUMBER_RANGE    "[-0123456789]"
 934 #define        NUMBER_RANGE    "[0123456789eE+-]"
 935   char value[BUFLEN + 1];
 936   char value2[BUFLEN + 1];
 937   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_NUMBER_RANGE "." "%" XSTR(BUFLEN) NUMBER_RANGE "%c", name, value, value2, &dummy) == 3) {
 938     // Looks like a floating-point number -- try again with more lenient format string
 939     if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_FP_NUMBER_RANGE "%c", name, value, &dummy) == 2) {
 940       real_name = handle_aliases_and_deprecation(name, warn_if_deprecated);
 941       if (real_name == NULL) {
 942         return false;
 943       }
 944       return set_fp_numeric_flag(real_name, value, origin);
 945     }
 946   }
 947 
 948 #define VALUE_RANGE "[-kmgtxKMGTX0123456789abcdefABCDEF]"
 949   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) VALUE_RANGE "%c", name, value, &dummy) == 2) {
 950     real_name = handle_aliases_and_deprecation(name, warn_if_deprecated);
 951     if (real_name == NULL) {
 952       return false;
 953     }
 954     return set_numeric_flag(real_name, value, origin);
 955   }
 956 
 957   return false;
 958 }
 959 
 960 void Arguments::add_string(char*** bldarray, int* count, const char* arg) {
 961   assert(bldarray != NULL, "illegal argument");
 962 
 963   if (arg == NULL) {
 964     return;
 965   }
 966 
 967   int new_count = *count + 1;
 968 
 969   // expand the array and add arg to the last element
 970   if (*bldarray == NULL) {
 971     *bldarray = NEW_C_HEAP_ARRAY(char*, new_count, mtArguments);
 972   } else {
 973     *bldarray = REALLOC_C_HEAP_ARRAY(char*, *bldarray, new_count, mtArguments);
 974   }
 975   (*bldarray)[*count] = os::strdup_check_oom(arg);
 976   *count = new_count;
 977 }
 978 
 979 void Arguments::build_jvm_args(const char* arg) {
 980   add_string(&_jvm_args_array, &_num_jvm_args, arg);
 981 }
 982 
 983 void Arguments::build_jvm_flags(const char* arg) {
 984   add_string(&_jvm_flags_array, &_num_jvm_flags, arg);
 985 }
 986 
 987 // utility function to return a string that concatenates all
 988 // strings in a given char** array
 989 const char* Arguments::build_resource_string(char** args, int count) {
 990   if (args == NULL || count == 0) {
 991     return NULL;
 992   }
 993   size_t length = 0;
 994   for (int i = 0; i < count; i++) {
 995     length += strlen(args[i]) + 1; // add 1 for a space or NULL terminating character
 996   }
 997   char* s = NEW_RESOURCE_ARRAY(char, length);
 998   char* dst = s;
 999   for (int j = 0; j < count; j++) {
1000     size_t offset = strlen(args[j]) + 1; // add 1 for a space or NULL terminating character
1001     jio_snprintf(dst, length, "%s ", args[j]); // jio_snprintf will replace the last space character with NULL character
1002     dst += offset;
1003     length -= offset;
1004   }
1005   return (const char*) s;
1006 }
1007 
1008 void Arguments::print_on(outputStream* st) {
1009   st->print_cr("VM Arguments:");
1010   if (num_jvm_flags() > 0) {
1011     st->print("jvm_flags: "); print_jvm_flags_on(st);
1012     st->cr();
1013   }
1014   if (num_jvm_args() > 0) {
1015     st->print("jvm_args: "); print_jvm_args_on(st);
1016     st->cr();
1017   }
1018   st->print_cr("java_command: %s", java_command() ? java_command() : "<unknown>");
1019   if (_java_class_path != NULL) {
1020     char* path = _java_class_path->value();
1021     st->print_cr("java_class_path (initial): %s", strlen(path) == 0 ? "<not set>" : path );
1022   }
1023   st->print_cr("Launcher Type: %s", _sun_java_launcher);
1024 }
1025 
1026 void Arguments::print_summary_on(outputStream* st) {
1027   // Print the command line.  Environment variables that are helpful for
1028   // reproducing the problem are written later in the hs_err file.
1029   // flags are from setting file
1030   if (num_jvm_flags() > 0) {
1031     st->print_raw("Settings File: ");
1032     print_jvm_flags_on(st);
1033     st->cr();
1034   }
1035   // args are the command line and environment variable arguments.
1036   st->print_raw("Command Line: ");
1037   if (num_jvm_args() > 0) {
1038     print_jvm_args_on(st);
1039   }
1040   // this is the classfile and any arguments to the java program
1041   if (java_command() != NULL) {
1042     st->print("%s", java_command());
1043   }
1044   st->cr();
1045 }
1046 
1047 void Arguments::print_jvm_flags_on(outputStream* st) {
1048   if (_num_jvm_flags > 0) {
1049     for (int i=0; i < _num_jvm_flags; i++) {
1050       st->print("%s ", _jvm_flags_array[i]);
1051     }
1052   }
1053 }
1054 
1055 void Arguments::print_jvm_args_on(outputStream* st) {
1056   if (_num_jvm_args > 0) {
1057     for (int i=0; i < _num_jvm_args; i++) {
1058       st->print("%s ", _jvm_args_array[i]);
1059     }
1060   }
1061 }
1062 
1063 bool Arguments::process_argument(const char* arg,
1064                                  jboolean ignore_unrecognized,
1065                                  Flag::Flags origin) {
1066   JDK_Version since = JDK_Version();
1067 
1068   if (parse_argument(arg, origin)) {
1069     return true;
1070   }
1071 
1072   // Determine if the flag has '+', '-', or '=' characters.
1073   bool has_plus_minus = (*arg == '+' || *arg == '-');
1074   const char* const argname = has_plus_minus ? arg + 1 : arg;
1075 
1076   size_t arg_len;
1077   const char* equal_sign = strchr(argname, '=');
1078   if (equal_sign == NULL) {
1079     arg_len = strlen(argname);
1080   } else {
1081     arg_len = equal_sign - argname;
1082   }
1083 
1084   // Only make the obsolete check for valid arguments.
1085   if (arg_len <= BUFLEN) {
1086     // Construct a string which consists only of the argument name without '+', '-', or '='.
1087     char stripped_argname[BUFLEN+1]; // +1 for '\0'
1088     jio_snprintf(stripped_argname, arg_len+1, "%s", argname); // +1 for '\0'
1089     if (is_obsolete_flag(stripped_argname, &since)) {
1090       char version[256];
1091       since.to_string(version, sizeof(version));
1092       warning("Ignoring option %s; support was removed in %s", stripped_argname, version);
1093       return true;
1094     }
1095 #ifndef PRODUCT
1096     else {
1097       const char* replacement;
1098       if ((replacement = removed_develop_logging_flag_name(stripped_argname)) != NULL){
1099         log_warning(arguments)("%s has been removed. Please use %s instead.",
1100                                stripped_argname,
1101                                replacement);
1102         return false;
1103       }
1104     }
1105 #endif //PRODUCT
1106   }
1107 
1108   // For locked flags, report a custom error message if available.
1109   // Otherwise, report the standard unrecognized VM option.
1110   Flag* found_flag = Flag::find_flag((const char*)argname, arg_len, true, true);
1111   if (found_flag != NULL) {
1112     char locked_message_buf[BUFLEN];
1113     Flag::MsgType msg_type = found_flag->get_locked_message(locked_message_buf, BUFLEN);
1114     if (strlen(locked_message_buf) == 0) {
1115       if (found_flag->is_bool() && !has_plus_minus) {
1116         jio_fprintf(defaultStream::error_stream(),
1117           "Missing +/- setting for VM option '%s'\n", argname);
1118       } else if (!found_flag->is_bool() && has_plus_minus) {
1119         jio_fprintf(defaultStream::error_stream(),
1120           "Unexpected +/- setting in VM option '%s'\n", argname);
1121       } else {
1122         jio_fprintf(defaultStream::error_stream(),
1123           "Improperly specified VM option '%s'\n", argname);
1124       }
1125     } else {
1126 #ifdef PRODUCT
1127       bool mismatched = ((msg_type == Flag::NOTPRODUCT_FLAG_BUT_PRODUCT_BUILD) ||
1128                          (msg_type == Flag::DEVELOPER_FLAG_BUT_PRODUCT_BUILD));
1129       if (ignore_unrecognized && mismatched) {
1130         return true;
1131       }
1132 #endif
1133       jio_fprintf(defaultStream::error_stream(), "%s", locked_message_buf);
1134     }
1135   } else {
1136     if (ignore_unrecognized) {
1137       return true;
1138     }
1139     jio_fprintf(defaultStream::error_stream(),
1140                 "Unrecognized VM option '%s'\n", argname);
1141     Flag* fuzzy_matched = Flag::fuzzy_match((const char*)argname, arg_len, true);
1142     if (fuzzy_matched != NULL) {
1143       jio_fprintf(defaultStream::error_stream(),
1144                   "Did you mean '%s%s%s'? ",
1145                   (fuzzy_matched->is_bool()) ? "(+/-)" : "",
1146                   fuzzy_matched->_name,
1147                   (fuzzy_matched->is_bool()) ? "" : "=<value>");
1148     }
1149   }
1150 
1151   // allow for commandline "commenting out" options like -XX:#+Verbose
1152   return arg[0] == '#';
1153 }
1154 
1155 bool Arguments::process_settings_file(const char* file_name, bool should_exist, jboolean ignore_unrecognized) {
1156   FILE* stream = fopen(file_name, "rb");
1157   if (stream == NULL) {
1158     if (should_exist) {
1159       jio_fprintf(defaultStream::error_stream(),
1160                   "Could not open settings file %s\n", file_name);
1161       return false;
1162     } else {
1163       return true;
1164     }
1165   }
1166 
1167   char token[1024];
1168   int  pos = 0;
1169 
1170   bool in_white_space = true;
1171   bool in_comment     = false;
1172   bool in_quote       = false;
1173   char quote_c        = 0;
1174   bool result         = true;
1175 
1176   int c = getc(stream);
1177   while(c != EOF && pos < (int)(sizeof(token)-1)) {
1178     if (in_white_space) {
1179       if (in_comment) {
1180         if (c == '\n') in_comment = false;
1181       } else {
1182         if (c == '#') in_comment = true;
1183         else if (!isspace(c)) {
1184           in_white_space = false;
1185           token[pos++] = c;
1186         }
1187       }
1188     } else {
1189       if (c == '\n' || (!in_quote && isspace(c))) {
1190         // token ends at newline, or at unquoted whitespace
1191         // this allows a way to include spaces in string-valued options
1192         token[pos] = '\0';
1193         logOption(token);
1194         result &= process_argument(token, ignore_unrecognized, Flag::CONFIG_FILE);
1195         build_jvm_flags(token);
1196         pos = 0;
1197         in_white_space = true;
1198         in_quote = false;
1199       } else if (!in_quote && (c == '\'' || c == '"')) {
1200         in_quote = true;
1201         quote_c = c;
1202       } else if (in_quote && (c == quote_c)) {
1203         in_quote = false;
1204       } else {
1205         token[pos++] = c;
1206       }
1207     }
1208     c = getc(stream);
1209   }
1210   if (pos > 0) {
1211     token[pos] = '\0';
1212     result &= process_argument(token, ignore_unrecognized, Flag::CONFIG_FILE);
1213     build_jvm_flags(token);
1214   }
1215   fclose(stream);
1216   return result;
1217 }
1218 
1219 //=============================================================================================================
1220 // Parsing of properties (-D)
1221 
1222 const char* Arguments::get_property(const char* key) {
1223   return PropertyList_get_value(system_properties(), key);
1224 }
1225 
1226 bool Arguments::add_property(const char* prop, PropertyWriteable writeable, PropertyInternal internal) {
1227   const char* eq = strchr(prop, '=');
1228   const char* key;
1229   const char* value = "";
1230 
1231   if (eq == NULL) {
1232     // property doesn't have a value, thus use passed string
1233     key = prop;
1234   } else {
1235     // property have a value, thus extract it and save to the
1236     // allocated string
1237     size_t key_len = eq - prop;
1238     char* tmp_key = AllocateHeap(key_len + 1, mtArguments);
1239 
1240     jio_snprintf(tmp_key, key_len + 1, "%s", prop);
1241     key = tmp_key;
1242 
1243     value = &prop[key_len + 1];
1244   }
1245 
1246   if (strcmp(key, "java.compiler") == 0) {
1247     process_java_compiler_argument(value);
1248     // Record value in Arguments, but let it get passed to Java.
1249   } else if (strcmp(key, "sun.java.launcher.is_altjvm") == 0 ||
1250              strcmp(key, "sun.java.launcher.pid") == 0) {
1251     // sun.java.launcher.is_altjvm and sun.java.launcher.pid property are
1252     // private and are processed in process_sun_java_launcher_properties();
1253     // the sun.java.launcher property is passed on to the java application
1254   } else if (strcmp(key, "sun.boot.library.path") == 0) {
1255     // append is true, writable is true, internal is false
1256     PropertyList_unique_add(&_system_properties, key, value, AppendProperty,
1257                             WriteableProperty, ExternalProperty);
1258   } else {
1259     if (strcmp(key, "sun.java.command") == 0) {
1260       char *old_java_command = _java_command;
1261       _java_command = os::strdup_check_oom(value, mtArguments);
1262       if (old_java_command != NULL) {
1263         os::free(old_java_command);
1264       }
1265     } else if (strcmp(key, "java.vendor.url.bug") == 0) {
1266       const char* old_java_vendor_url_bug = _java_vendor_url_bug;
1267       // save it in _java_vendor_url_bug, so JVM fatal error handler can access
1268       // its value without going through the property list or making a Java call.
1269       _java_vendor_url_bug = os::strdup_check_oom(value, mtArguments);
1270       if (old_java_vendor_url_bug != DEFAULT_VENDOR_URL_BUG) {
1271         assert(old_java_vendor_url_bug != NULL, "_java_vendor_url_bug is NULL");
1272         os::free((void *)old_java_vendor_url_bug);
1273       }
1274     }
1275 
1276     // Create new property and add at the end of the list
1277     PropertyList_unique_add(&_system_properties, key, value, AddProperty, writeable, internal);
1278   }
1279 
1280   if (key != prop) {
1281     // SystemProperty copy passed value, thus free previously allocated
1282     // memory
1283     FreeHeap((void *)key);
1284   }
1285 
1286   return true;
1287 }
1288 
1289 #if INCLUDE_CDS
1290 void Arguments::check_unsupported_dumping_properties() {
1291   assert(DumpSharedSpaces, "this function is only used with -Xshare:dump");
1292   const char* unsupported_properties[] = { "jdk.module.main",
1293                                            "jdk.module.limitmods",
1294                                            "jdk.module.path",
1295                                            "jdk.module.upgrade.path",
1296                                            "jdk.module.patch.0" };
1297   const char* unsupported_options[] = { "-m", // cannot use at dump time
1298                                         "--limit-modules", // ignored at dump time
1299                                         "--module-path", // ignored at dump time
1300                                         "--upgrade-module-path", // ignored at dump time
1301                                         "--patch-module" // ignored at dump time
1302                                       };
1303   assert(ARRAY_SIZE(unsupported_properties) == ARRAY_SIZE(unsupported_options), "must be");
1304   // If a vm option is found in the unsupported_options array with index less than the info_idx,
1305   // vm will exit with an error message. Otherwise, it will print an informational message if
1306   // -Xlog:cds is enabled.
1307   uint info_idx = 1;
1308   SystemProperty* sp = system_properties();
1309   while (sp != NULL) {
1310     for (uint i = 0; i < ARRAY_SIZE(unsupported_properties); i++) {
1311       if (strcmp(sp->key(), unsupported_properties[i]) == 0) {
1312         if (i < info_idx) {
1313           vm_exit_during_initialization(
1314             "Cannot use the following option when dumping the shared archive", unsupported_options[i]);
1315         } else {
1316           log_info(cds)("Info: the %s option is ignored when dumping the shared archive",
1317                         unsupported_options[i]);
1318         }
1319       }
1320     }
1321     sp = sp->next();
1322   }
1323 
1324   // Check for an exploded module build in use with -Xshare:dump.
1325   if (!has_jimage()) {
1326     vm_exit_during_initialization("Dumping the shared archive is not supported with an exploded module build");
1327   }
1328 }
1329 #endif
1330 
1331 //===========================================================================================================
1332 // Setting int/mixed/comp mode flags
1333 
1334 void Arguments::set_mode_flags(Mode mode) {
1335   // Set up default values for all flags.
1336   // If you add a flag to any of the branches below,
1337   // add a default value for it here.
1338   set_java_compiler(false);
1339   _mode                      = mode;
1340 
1341   // Ensure Agent_OnLoad has the correct initial values.
1342   // This may not be the final mode; mode may change later in onload phase.
1343   PropertyList_unique_add(&_system_properties, "java.vm.info",
1344                           VM_Version::vm_info_string(), AddProperty, UnwriteableProperty, ExternalProperty);
1345 
1346   UseInterpreter             = true;
1347   UseCompiler                = true;
1348   UseLoopCounter             = true;
1349 
1350   // Default values may be platform/compiler dependent -
1351   // use the saved values
1352   ClipInlining               = Arguments::_ClipInlining;
1353   AlwaysCompileLoopMethods   = Arguments::_AlwaysCompileLoopMethods;
1354   UseOnStackReplacement      = Arguments::_UseOnStackReplacement;
1355   BackgroundCompilation      = Arguments::_BackgroundCompilation;
1356   if (TieredCompilation) {
1357     if (FLAG_IS_DEFAULT(Tier3InvokeNotifyFreqLog)) {
1358       Tier3InvokeNotifyFreqLog = Arguments::_Tier3InvokeNotifyFreqLog;
1359     }
1360     if (FLAG_IS_DEFAULT(Tier4InvocationThreshold)) {
1361       Tier4InvocationThreshold = Arguments::_Tier4InvocationThreshold;
1362     }
1363   }
1364 
1365   // Change from defaults based on mode
1366   switch (mode) {
1367   default:
1368     ShouldNotReachHere();
1369     break;
1370   case _int:
1371     UseCompiler              = false;
1372     UseLoopCounter           = false;
1373     AlwaysCompileLoopMethods = false;
1374     UseOnStackReplacement    = false;
1375     break;
1376   case _mixed:
1377     // same as default
1378     break;
1379   case _comp:
1380     UseInterpreter           = false;
1381     BackgroundCompilation    = false;
1382     ClipInlining             = false;
1383     // Be much more aggressive in tiered mode with -Xcomp and exercise C2 more.
1384     // We will first compile a level 3 version (C1 with full profiling), then do one invocation of it and
1385     // compile a level 4 (C2) and then continue executing it.
1386     if (TieredCompilation) {
1387       Tier3InvokeNotifyFreqLog = 0;
1388       Tier4InvocationThreshold = 0;
1389     }
1390     break;
1391   }
1392 }
1393 
1394 // Conflict: required to use shared spaces (-Xshare:on), but
1395 // incompatible command line options were chosen.
1396 static void no_shared_spaces(const char* message) {
1397   if (RequireSharedSpaces) {
1398     jio_fprintf(defaultStream::error_stream(),
1399       "Class data sharing is inconsistent with other specified options.\n");
1400     vm_exit_during_initialization("Unable to use shared archive.", message);
1401   } else {
1402     FLAG_SET_DEFAULT(UseSharedSpaces, false);
1403   }
1404 }
1405 
1406 // Returns threshold scaled with the value of scale.
1407 // If scale < 0.0, threshold is returned without scaling.
1408 intx Arguments::scaled_compile_threshold(intx threshold, double scale) {
1409   if (scale == 1.0 || scale < 0.0) {
1410     return threshold;
1411   } else {
1412     return (intx)(threshold * scale);
1413   }
1414 }
1415 
1416 // Returns freq_log scaled with the value of scale.
1417 // Returned values are in the range of [0, InvocationCounter::number_of_count_bits + 1].
1418 // If scale < 0.0, freq_log is returned without scaling.
1419 intx Arguments::scaled_freq_log(intx freq_log, double scale) {
1420   // Check if scaling is necessary or if negative value was specified.
1421   if (scale == 1.0 || scale < 0.0) {
1422     return freq_log;
1423   }
1424   // Check values to avoid calculating log2 of 0.
1425   if (scale == 0.0 || freq_log == 0) {
1426     return 0;
1427   }
1428   // Determine the maximum notification frequency value currently supported.
1429   // The largest mask value that the interpreter/C1 can handle is
1430   // of length InvocationCounter::number_of_count_bits. Mask values are always
1431   // one bit shorter then the value of the notification frequency. Set
1432   // max_freq_bits accordingly.
1433   intx max_freq_bits = InvocationCounter::number_of_count_bits + 1;
1434   intx scaled_freq = scaled_compile_threshold((intx)1 << freq_log, scale);
1435   if (scaled_freq == 0) {
1436     // Return 0 right away to avoid calculating log2 of 0.
1437     return 0;
1438   } else if (scaled_freq > nth_bit(max_freq_bits)) {
1439     return max_freq_bits;
1440   } else {
1441     return log2_intptr(scaled_freq);
1442   }
1443 }
1444 
1445 void Arguments::set_tiered_flags() {
1446   // With tiered, set default policy to AdvancedThresholdPolicy, which is 3.
1447   if (FLAG_IS_DEFAULT(CompilationPolicyChoice)) {
1448     FLAG_SET_DEFAULT(CompilationPolicyChoice, 3);
1449   }
1450   if (CompilationPolicyChoice < 2) {
1451     vm_exit_during_initialization(
1452       "Incompatible compilation policy selected", NULL);
1453   }
1454   // Increase the code cache size - tiered compiles a lot more.
1455   if (FLAG_IS_DEFAULT(ReservedCodeCacheSize)) {
1456     FLAG_SET_ERGO(uintx, ReservedCodeCacheSize,
1457                   MIN2(CODE_CACHE_DEFAULT_LIMIT, ReservedCodeCacheSize * 5));
1458   }
1459   // Enable SegmentedCodeCache if TieredCompilation is enabled and ReservedCodeCacheSize >= 240M
1460   if (FLAG_IS_DEFAULT(SegmentedCodeCache) && ReservedCodeCacheSize >= 240*M) {
1461     FLAG_SET_ERGO(bool, SegmentedCodeCache, true);
1462   }
1463   if (!UseInterpreter) { // -Xcomp
1464     Tier3InvokeNotifyFreqLog = 0;
1465     Tier4InvocationThreshold = 0;
1466   }
1467 
1468   if (CompileThresholdScaling < 0) {
1469     vm_exit_during_initialization("Negative value specified for CompileThresholdScaling", NULL);
1470   }
1471 
1472   // Scale tiered compilation thresholds.
1473   // CompileThresholdScaling == 0.0 is equivalent to -Xint and leaves compilation thresholds unchanged.
1474   if (!FLAG_IS_DEFAULT(CompileThresholdScaling) && CompileThresholdScaling > 0.0) {
1475     FLAG_SET_ERGO(intx, Tier0InvokeNotifyFreqLog, scaled_freq_log(Tier0InvokeNotifyFreqLog));
1476     FLAG_SET_ERGO(intx, Tier0BackedgeNotifyFreqLog, scaled_freq_log(Tier0BackedgeNotifyFreqLog));
1477 
1478     FLAG_SET_ERGO(intx, Tier3InvocationThreshold, scaled_compile_threshold(Tier3InvocationThreshold));
1479     FLAG_SET_ERGO(intx, Tier3MinInvocationThreshold, scaled_compile_threshold(Tier3MinInvocationThreshold));
1480     FLAG_SET_ERGO(intx, Tier3CompileThreshold, scaled_compile_threshold(Tier3CompileThreshold));
1481     FLAG_SET_ERGO(intx, Tier3BackEdgeThreshold, scaled_compile_threshold(Tier3BackEdgeThreshold));
1482 
1483     // Tier2{Invocation,MinInvocation,Compile,Backedge}Threshold should be scaled here
1484     // once these thresholds become supported.
1485 
1486     FLAG_SET_ERGO(intx, Tier2InvokeNotifyFreqLog, scaled_freq_log(Tier2InvokeNotifyFreqLog));
1487     FLAG_SET_ERGO(intx, Tier2BackedgeNotifyFreqLog, scaled_freq_log(Tier2BackedgeNotifyFreqLog));
1488 
1489     FLAG_SET_ERGO(intx, Tier3InvokeNotifyFreqLog, scaled_freq_log(Tier3InvokeNotifyFreqLog));
1490     FLAG_SET_ERGO(intx, Tier3BackedgeNotifyFreqLog, scaled_freq_log(Tier3BackedgeNotifyFreqLog));
1491 
1492     FLAG_SET_ERGO(intx, Tier23InlineeNotifyFreqLog, scaled_freq_log(Tier23InlineeNotifyFreqLog));
1493 
1494     FLAG_SET_ERGO(intx, Tier4InvocationThreshold, scaled_compile_threshold(Tier4InvocationThreshold));
1495     FLAG_SET_ERGO(intx, Tier4MinInvocationThreshold, scaled_compile_threshold(Tier4MinInvocationThreshold));
1496     FLAG_SET_ERGO(intx, Tier4CompileThreshold, scaled_compile_threshold(Tier4CompileThreshold));
1497     FLAG_SET_ERGO(intx, Tier4BackEdgeThreshold, scaled_compile_threshold(Tier4BackEdgeThreshold));
1498   }
1499 }
1500 
1501 #if INCLUDE_ALL_GCS
1502 static void disable_adaptive_size_policy(const char* collector_name) {
1503   if (UseAdaptiveSizePolicy) {
1504     if (FLAG_IS_CMDLINE(UseAdaptiveSizePolicy)) {
1505       warning("Disabling UseAdaptiveSizePolicy; it is incompatible with %s.",
1506               collector_name);
1507     }
1508     FLAG_SET_DEFAULT(UseAdaptiveSizePolicy, false);
1509   }
1510 }
1511 
1512 void Arguments::set_parnew_gc_flags() {
1513   assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC && !UseG1GC,
1514          "control point invariant");
1515   assert(UseConcMarkSweepGC, "CMS is expected to be on here");
1516 
1517   if (FLAG_IS_DEFAULT(ParallelGCThreads)) {
1518     FLAG_SET_DEFAULT(ParallelGCThreads, Abstract_VM_Version::parallel_worker_threads());
1519     assert(ParallelGCThreads > 0, "We should always have at least one thread by default");
1520   } else if (ParallelGCThreads == 0) {
1521     jio_fprintf(defaultStream::error_stream(),
1522         "The ParNew GC can not be combined with -XX:ParallelGCThreads=0\n");
1523     vm_exit(1);
1524   }
1525 
1526   // By default YoungPLABSize and OldPLABSize are set to 4096 and 1024 respectively,
1527   // these settings are default for Parallel Scavenger. For ParNew+Tenured configuration
1528   // we set them to 1024 and 1024.
1529   // See CR 6362902.
1530   if (FLAG_IS_DEFAULT(YoungPLABSize)) {
1531     FLAG_SET_DEFAULT(YoungPLABSize, (intx)1024);
1532   }
1533   if (FLAG_IS_DEFAULT(OldPLABSize)) {
1534     FLAG_SET_DEFAULT(OldPLABSize, (intx)1024);
1535   }
1536 
1537   // When using compressed oops, we use local overflow stacks,
1538   // rather than using a global overflow list chained through
1539   // the klass word of the object's pre-image.
1540   if (UseCompressedOops && !ParGCUseLocalOverflow) {
1541     if (!FLAG_IS_DEFAULT(ParGCUseLocalOverflow)) {
1542       warning("Forcing +ParGCUseLocalOverflow: needed if using compressed references");
1543     }
1544     FLAG_SET_DEFAULT(ParGCUseLocalOverflow, true);
1545   }
1546   assert(ParGCUseLocalOverflow || !UseCompressedOops, "Error");
1547 }
1548 
1549 // Adjust some sizes to suit CMS and/or ParNew needs; these work well on
1550 // sparc/solaris for certain applications, but would gain from
1551 // further optimization and tuning efforts, and would almost
1552 // certainly gain from analysis of platform and environment.
1553 void Arguments::set_cms_and_parnew_gc_flags() {
1554   assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC, "Error");
1555   assert(UseConcMarkSweepGC, "CMS is expected to be on here");
1556 
1557   // Turn off AdaptiveSizePolicy by default for cms until it is complete.
1558   disable_adaptive_size_policy("UseConcMarkSweepGC");
1559 
1560   set_parnew_gc_flags();
1561 
1562   size_t max_heap = align_down(MaxHeapSize,
1563                                CardTableRS::ct_max_alignment_constraint());
1564 
1565   // Now make adjustments for CMS
1566   intx   tenuring_default = (intx)6;
1567   size_t young_gen_per_worker = CMSYoungGenPerWorker;
1568 
1569   // Preferred young gen size for "short" pauses:
1570   // upper bound depends on # of threads and NewRatio.
1571   const size_t preferred_max_new_size_unaligned =
1572     MIN2(max_heap/(NewRatio+1), ScaleForWordSize(young_gen_per_worker * ParallelGCThreads));
1573   size_t preferred_max_new_size =
1574     align_up(preferred_max_new_size_unaligned, os::vm_page_size());
1575 
1576   // Unless explicitly requested otherwise, size young gen
1577   // for "short" pauses ~ CMSYoungGenPerWorker*ParallelGCThreads
1578 
1579   // If either MaxNewSize or NewRatio is set on the command line,
1580   // assume the user is trying to set the size of the young gen.
1581   if (FLAG_IS_DEFAULT(MaxNewSize) && FLAG_IS_DEFAULT(NewRatio)) {
1582 
1583     // Set MaxNewSize to our calculated preferred_max_new_size unless
1584     // NewSize was set on the command line and it is larger than
1585     // preferred_max_new_size.
1586     if (!FLAG_IS_DEFAULT(NewSize)) {   // NewSize explicitly set at command-line
1587       FLAG_SET_ERGO(size_t, MaxNewSize, MAX2(NewSize, preferred_max_new_size));
1588     } else {
1589       FLAG_SET_ERGO(size_t, MaxNewSize, preferred_max_new_size);
1590     }
1591     log_trace(gc, heap)("CMS ergo set MaxNewSize: " SIZE_FORMAT, MaxNewSize);
1592 
1593     // Code along this path potentially sets NewSize and OldSize
1594     log_trace(gc, heap)("CMS set min_heap_size: " SIZE_FORMAT " initial_heap_size:  " SIZE_FORMAT " max_heap: " SIZE_FORMAT,
1595                         min_heap_size(), InitialHeapSize, max_heap);
1596     size_t min_new = preferred_max_new_size;
1597     if (FLAG_IS_CMDLINE(NewSize)) {
1598       min_new = NewSize;
1599     }
1600     if (max_heap > min_new && min_heap_size() > min_new) {
1601       // Unless explicitly requested otherwise, make young gen
1602       // at least min_new, and at most preferred_max_new_size.
1603       if (FLAG_IS_DEFAULT(NewSize)) {
1604         FLAG_SET_ERGO(size_t, NewSize, MAX2(NewSize, min_new));
1605         FLAG_SET_ERGO(size_t, NewSize, MIN2(preferred_max_new_size, NewSize));
1606         log_trace(gc, heap)("CMS ergo set NewSize: " SIZE_FORMAT, NewSize);
1607       }
1608       // Unless explicitly requested otherwise, size old gen
1609       // so it's NewRatio x of NewSize.
1610       if (FLAG_IS_DEFAULT(OldSize)) {
1611         if (max_heap > NewSize) {
1612           FLAG_SET_ERGO(size_t, OldSize, MIN2(NewRatio*NewSize, max_heap - NewSize));
1613           log_trace(gc, heap)("CMS ergo set OldSize: " SIZE_FORMAT, OldSize);
1614         }
1615       }
1616     }
1617   }
1618   // Unless explicitly requested otherwise, definitely
1619   // promote all objects surviving "tenuring_default" scavenges.
1620   if (FLAG_IS_DEFAULT(MaxTenuringThreshold) &&
1621       FLAG_IS_DEFAULT(SurvivorRatio)) {
1622     FLAG_SET_ERGO(uintx, MaxTenuringThreshold, tenuring_default);
1623   }
1624   // If we decided above (or user explicitly requested)
1625   // `promote all' (via MaxTenuringThreshold := 0),
1626   // prefer minuscule survivor spaces so as not to waste
1627   // space for (non-existent) survivors
1628   if (FLAG_IS_DEFAULT(SurvivorRatio) && MaxTenuringThreshold == 0) {
1629     FLAG_SET_ERGO(uintx, SurvivorRatio, MAX2((uintx)1024, SurvivorRatio));
1630   }
1631 
1632   // OldPLABSize is interpreted in CMS as not the size of the PLAB in words,
1633   // but rather the number of free blocks of a given size that are used when
1634   // replenishing the local per-worker free list caches.
1635   if (FLAG_IS_DEFAULT(OldPLABSize)) {
1636     if (!FLAG_IS_DEFAULT(ResizeOldPLAB) && !ResizeOldPLAB) {
1637       // OldPLAB sizing manually turned off: Use a larger default setting,
1638       // unless it was manually specified. This is because a too-low value
1639       // will slow down scavenges.
1640       FLAG_SET_ERGO(size_t, OldPLABSize, CompactibleFreeListSpaceLAB::_default_static_old_plab_size); // default value before 6631166
1641     } else {
1642       FLAG_SET_DEFAULT(OldPLABSize, CompactibleFreeListSpaceLAB::_default_dynamic_old_plab_size); // old CMSParPromoteBlocksToClaim default
1643     }
1644   }
1645 
1646   // If either of the static initialization defaults have changed, note this
1647   // modification.
1648   if (!FLAG_IS_DEFAULT(OldPLABSize) || !FLAG_IS_DEFAULT(OldPLABWeight)) {
1649     CompactibleFreeListSpaceLAB::modify_initialization(OldPLABSize, OldPLABWeight);
1650   }
1651 
1652   log_trace(gc)("MarkStackSize: %uk  MarkStackSizeMax: %uk", (unsigned int) (MarkStackSize / K), (uint) (MarkStackSizeMax / K));
1653 }
1654 #endif // INCLUDE_ALL_GCS
1655 
1656 void set_object_alignment() {
1657   // Object alignment.
1658   assert(is_power_of_2(ObjectAlignmentInBytes), "ObjectAlignmentInBytes must be power of 2");
1659   MinObjAlignmentInBytes     = ObjectAlignmentInBytes;
1660   assert(MinObjAlignmentInBytes >= HeapWordsPerLong * HeapWordSize, "ObjectAlignmentInBytes value is too small");
1661   MinObjAlignment            = MinObjAlignmentInBytes / HeapWordSize;
1662   assert(MinObjAlignmentInBytes == MinObjAlignment * HeapWordSize, "ObjectAlignmentInBytes value is incorrect");
1663   MinObjAlignmentInBytesMask = MinObjAlignmentInBytes - 1;
1664 
1665   LogMinObjAlignmentInBytes  = exact_log2(ObjectAlignmentInBytes);
1666   LogMinObjAlignment         = LogMinObjAlignmentInBytes - LogHeapWordSize;
1667 
1668   // Oop encoding heap max
1669   OopEncodingHeapMax = (uint64_t(max_juint) + 1) << LogMinObjAlignmentInBytes;
1670 
1671   if (SurvivorAlignmentInBytes == 0) {
1672     SurvivorAlignmentInBytes = ObjectAlignmentInBytes;
1673   }
1674 
1675 #if INCLUDE_ALL_GCS
1676   // Set CMS global values
1677   CompactibleFreeListSpace::set_cms_values();
1678 #endif // INCLUDE_ALL_GCS
1679 }
1680 
1681 size_t Arguments::max_heap_for_compressed_oops() {
1682   // Avoid sign flip.
1683   assert(OopEncodingHeapMax > (uint64_t)os::vm_page_size(), "Unusual page size");
1684   // We need to fit both the NULL page and the heap into the memory budget, while
1685   // keeping alignment constraints of the heap. To guarantee the latter, as the
1686   // NULL page is located before the heap, we pad the NULL page to the conservative
1687   // maximum alignment that the GC may ever impose upon the heap.
1688   size_t displacement_due_to_null_page = align_up((size_t)os::vm_page_size(),
1689                                                   _conservative_max_heap_alignment);
1690 
1691   LP64_ONLY(return OopEncodingHeapMax - displacement_due_to_null_page);
1692   NOT_LP64(ShouldNotReachHere(); return 0);
1693 }
1694 
1695 void Arguments::set_use_compressed_oops() {
1696 #ifndef ZERO
1697 #ifdef _LP64
1698   // MaxHeapSize is not set up properly at this point, but
1699   // the only value that can override MaxHeapSize if we are
1700   // to use UseCompressedOops is InitialHeapSize.
1701   size_t max_heap_size = MAX2(MaxHeapSize, InitialHeapSize);
1702 
1703   if (max_heap_size <= max_heap_for_compressed_oops()) {
1704 #if !defined(COMPILER1) || defined(TIERED)
1705     if (FLAG_IS_DEFAULT(UseCompressedOops)) {
1706       FLAG_SET_ERGO(bool, UseCompressedOops, true);
1707     }
1708 #endif
1709   } else {
1710     if (UseCompressedOops && !FLAG_IS_DEFAULT(UseCompressedOops)) {
1711       warning("Max heap size too large for Compressed Oops");
1712       FLAG_SET_DEFAULT(UseCompressedOops, false);
1713       FLAG_SET_DEFAULT(UseCompressedClassPointers, false);
1714     }
1715   }
1716 #endif // _LP64
1717 #endif // ZERO
1718 }
1719 
1720 
1721 // NOTE: set_use_compressed_klass_ptrs() must be called after calling
1722 // set_use_compressed_oops().
1723 void Arguments::set_use_compressed_klass_ptrs() {
1724 #ifndef ZERO
1725 #ifdef _LP64
1726   // UseCompressedOops must be on for UseCompressedClassPointers to be on.
1727   if (!UseCompressedOops) {
1728     if (UseCompressedClassPointers) {
1729       warning("UseCompressedClassPointers requires UseCompressedOops");
1730     }
1731     FLAG_SET_DEFAULT(UseCompressedClassPointers, false);
1732   } else {
1733     // Turn on UseCompressedClassPointers too
1734     if (FLAG_IS_DEFAULT(UseCompressedClassPointers)) {
1735       FLAG_SET_ERGO(bool, UseCompressedClassPointers, true);
1736     }
1737     // Check the CompressedClassSpaceSize to make sure we use compressed klass ptrs.
1738     if (UseCompressedClassPointers) {
1739       size_t min_metaspace_sz = InitialBootClassLoaderMetaspaceSize +
1740                                (64 * K * HeapWordSize); // MediumChunk in bytes.
1741 
1742       if ((min_metaspace_sz + CompressedClassSpaceSize) >  MaxMetaspaceSize) {
1743         if (min_metaspace_sz >= MaxMetaspaceSize) {
1744           vm_exit_during_initialization(
1745                    "InitialBootClassLoaderMetaspaceSize should be " 
1746                                                 "less than MaxMetaspaceSize.");
1747         } else {
1748           FLAG_SET_ERGO(size_t, CompressedClassSpaceSize,
1749                                         MaxMetaspaceSize - min_metaspace_sz);
1750         }
1751       }
1752 
1753       if (CompressedClassSpaceSize > KlassEncodingMetaspaceMax) {
1754         warning("CompressedClassSpaceSize is too large for UseCompressedClassPointers");
1755         FLAG_SET_DEFAULT(UseCompressedClassPointers, false);
1756       }
1757     }
1758   }
1759 #endif // _LP64
1760 #endif // !ZERO
1761 }
1762 
1763 void Arguments::set_conservative_max_heap_alignment() {
1764   // The conservative maximum required alignment for the heap is the maximum of
1765   // the alignments imposed by several sources: any requirements from the heap
1766   // itself, the collector policy and the maximum page size we may run the VM
1767   // with.
1768   size_t heap_alignment = GenCollectedHeap::conservative_max_heap_alignment();
1769 #if INCLUDE_ALL_GCS
1770   if (UseParallelGC) {
1771     heap_alignment = ParallelScavengeHeap::conservative_max_heap_alignment();
1772   } else if (UseG1GC) {
1773     heap_alignment = G1CollectedHeap::conservative_max_heap_alignment();
1774   }
1775 #endif // INCLUDE_ALL_GCS
1776   _conservative_max_heap_alignment = MAX4(heap_alignment,
1777                                           (size_t)os::vm_allocation_granularity(),
1778                                           os::max_page_size(),
1779                                           CollectorPolicy::compute_heap_alignment());
1780 }
1781 
1782 bool Arguments::gc_selected() {
1783 #if INCLUDE_ALL_GCS
1784   return UseSerialGC || UseParallelGC || UseParallelOldGC || UseConcMarkSweepGC || UseG1GC;
1785 #else
1786   return UseSerialGC;
1787 #endif // INCLUDE_ALL_GCS
1788 }
1789 
1790 #ifdef TIERED
1791 bool Arguments::compilation_mode_selected() {
1792  return !FLAG_IS_DEFAULT(TieredCompilation) || !FLAG_IS_DEFAULT(TieredStopAtLevel) ||
1793         !FLAG_IS_DEFAULT(UseAOT) JVMCI_ONLY(|| !FLAG_IS_DEFAULT(EnableJVMCI) || !FLAG_IS_DEFAULT(UseJVMCICompiler));
1794 
1795 }
1796 
1797 void Arguments::select_compilation_mode_ergonomically() {
1798 #if defined(_WINDOWS) && !defined(_LP64)
1799   if (FLAG_IS_DEFAULT(NeverActAsServerClassMachine)) {
1800     FLAG_SET_ERGO(bool, NeverActAsServerClassMachine, true);
1801   }
1802 #endif
1803   if (NeverActAsServerClassMachine) {
1804     set_client_compilation_mode();
1805   }
1806 }
1807 #endif //TIERED
1808 
1809 void Arguments::select_gc_ergonomically() {
1810 #if INCLUDE_ALL_GCS
1811   if (os::is_server_class_machine()) {
1812     FLAG_SET_ERGO_IF_DEFAULT(bool, UseG1GC, true);
1813   } else {
1814     FLAG_SET_ERGO_IF_DEFAULT(bool, UseSerialGC, true);
1815   }
1816 #else
1817   UNSUPPORTED_OPTION(UseG1GC);
1818   UNSUPPORTED_OPTION(UseParallelGC);
1819   UNSUPPORTED_OPTION(UseParallelOldGC);
1820   UNSUPPORTED_OPTION(UseConcMarkSweepGC);
1821   FLAG_SET_ERGO_IF_DEFAULT(bool, UseSerialGC, true);
1822 #endif // INCLUDE_ALL_GCS
1823 }
1824 
1825 void Arguments::select_gc() {
1826   if (!gc_selected()) {
1827     select_gc_ergonomically();
1828     if (!gc_selected()) {
1829       vm_exit_during_initialization("Garbage collector not selected (default collector explicitly disabled)", NULL);
1830     }
1831   }
1832 }
1833 
1834 #if INCLUDE_JVMCI
1835 void Arguments::set_jvmci_specific_flags() {
1836   if (UseJVMCICompiler) {
1837     if (FLAG_IS_DEFAULT(TypeProfileWidth)) {
1838       FLAG_SET_DEFAULT(TypeProfileWidth, 8);
1839     }
1840     if (FLAG_IS_DEFAULT(OnStackReplacePercentage)) {
1841       FLAG_SET_DEFAULT(OnStackReplacePercentage, 933);
1842     }
1843     if (FLAG_IS_DEFAULT(ReservedCodeCacheSize)) {
1844       FLAG_SET_DEFAULT(ReservedCodeCacheSize, 64*M);
1845     }
1846     if (FLAG_IS_DEFAULT(InitialCodeCacheSize)) {
1847       FLAG_SET_DEFAULT(InitialCodeCacheSize, 16*M);
1848     }
1849     if (FLAG_IS_DEFAULT(MetaspaceSize)) {
1850       FLAG_SET_DEFAULT(MetaspaceSize, 12*M);
1851     }
1852     if (FLAG_IS_DEFAULT(NewSizeThreadIncrease)) {
1853       FLAG_SET_DEFAULT(NewSizeThreadIncrease, 4*K);
1854     }
1855     if (TieredStopAtLevel != CompLevel_full_optimization) {
1856       // Currently JVMCI compiler can only work at the full optimization level
1857       warning("forcing TieredStopAtLevel to full optimization because JVMCI is enabled");
1858       TieredStopAtLevel = CompLevel_full_optimization;
1859     }
1860     if (FLAG_IS_DEFAULT(TypeProfileLevel)) {
1861       FLAG_SET_DEFAULT(TypeProfileLevel, 0);
1862     }
1863   }
1864 }
1865 #endif
1866 
1867 void Arguments::set_ergonomics_flags() {
1868 #ifdef TIERED
1869   if (!compilation_mode_selected()) {
1870     select_compilation_mode_ergonomically();
1871   }
1872 #endif
1873   select_gc();
1874 
1875 #if defined(COMPILER2) || INCLUDE_JVMCI
1876   // Shared spaces work fine with other GCs but causes bytecode rewriting
1877   // to be disabled, which hurts interpreter performance and decreases
1878   // server performance.  When -server is specified, keep the default off
1879   // unless it is asked for.  Future work: either add bytecode rewriting
1880   // at link time, or rewrite bytecodes in non-shared methods.
1881   if (is_server_compilation_mode_vm() && !DumpSharedSpaces && !RequireSharedSpaces &&
1882       (FLAG_IS_DEFAULT(UseSharedSpaces) || !UseSharedSpaces)) {
1883     no_shared_spaces("COMPILER2 default: -Xshare:auto | off, have to manually setup to on.");
1884   }
1885 #endif
1886 
1887   set_conservative_max_heap_alignment();
1888 
1889 #ifndef ZERO
1890 #ifdef _LP64
1891   set_use_compressed_oops();
1892 
1893   // set_use_compressed_klass_ptrs() must be called after calling
1894   // set_use_compressed_oops().
1895   set_use_compressed_klass_ptrs();
1896 
1897   // Also checks that certain machines are slower with compressed oops
1898   // in vm_version initialization code.
1899 #endif // _LP64
1900 #endif // !ZERO
1901 
1902 }
1903 
1904 void Arguments::set_parallel_gc_flags() {
1905   assert(UseParallelGC || UseParallelOldGC, "Error");
1906   // Enable ParallelOld unless it was explicitly disabled (cmd line or rc file).
1907   if (FLAG_IS_DEFAULT(UseParallelOldGC)) {
1908     FLAG_SET_DEFAULT(UseParallelOldGC, true);
1909   }
1910   FLAG_SET_DEFAULT(UseParallelGC, true);
1911 
1912   // If no heap maximum was requested explicitly, use some reasonable fraction
1913   // of the physical memory, up to a maximum of 1GB.
1914   FLAG_SET_DEFAULT(ParallelGCThreads,
1915                    Abstract_VM_Version::parallel_worker_threads());
1916   if (ParallelGCThreads == 0) {
1917     jio_fprintf(defaultStream::error_stream(),
1918         "The Parallel GC can not be combined with -XX:ParallelGCThreads=0\n");
1919     vm_exit(1);
1920   }
1921 
1922   if (UseAdaptiveSizePolicy) {
1923     // We don't want to limit adaptive heap sizing's freedom to adjust the heap
1924     // unless the user actually sets these flags.
1925     if (FLAG_IS_DEFAULT(MinHeapFreeRatio)) {
1926       FLAG_SET_DEFAULT(MinHeapFreeRatio, 0);
1927     }
1928     if (FLAG_IS_DEFAULT(MaxHeapFreeRatio)) {
1929       FLAG_SET_DEFAULT(MaxHeapFreeRatio, 100);
1930     }
1931   }
1932 
1933   // If InitialSurvivorRatio or MinSurvivorRatio were not specified, but the
1934   // SurvivorRatio has been set, reset their default values to SurvivorRatio +
1935   // 2.  By doing this we make SurvivorRatio also work for Parallel Scavenger.
1936   // See CR 6362902 for details.
1937   if (!FLAG_IS_DEFAULT(SurvivorRatio)) {
1938     if (FLAG_IS_DEFAULT(InitialSurvivorRatio)) {
1939        FLAG_SET_DEFAULT(InitialSurvivorRatio, SurvivorRatio + 2);
1940     }
1941     if (FLAG_IS_DEFAULT(MinSurvivorRatio)) {
1942       FLAG_SET_DEFAULT(MinSurvivorRatio, SurvivorRatio + 2);
1943     }
1944   }
1945 
1946   if (UseParallelOldGC) {
1947     // Par compact uses lower default values since they are treated as
1948     // minimums.  These are different defaults because of the different
1949     // interpretation and are not ergonomically set.
1950     if (FLAG_IS_DEFAULT(MarkSweepDeadRatio)) {
1951       FLAG_SET_DEFAULT(MarkSweepDeadRatio, 1);
1952     }
1953   }
1954 }
1955 
1956 void Arguments::set_g1_gc_flags() {
1957   assert(UseG1GC, "Error");
1958 #if defined(COMPILER1) || INCLUDE_JVMCI
1959   FastTLABRefill = false;
1960 #endif
1961   FLAG_SET_DEFAULT(ParallelGCThreads, Abstract_VM_Version::parallel_worker_threads());
1962   if (ParallelGCThreads == 0) {
1963     assert(!FLAG_IS_DEFAULT(ParallelGCThreads), "The default value for ParallelGCThreads should not be 0.");
1964     vm_exit_during_initialization("The flag -XX:+UseG1GC can not be combined with -XX:ParallelGCThreads=0", NULL);
1965   }
1966 
1967 #if INCLUDE_ALL_GCS
1968   if (FLAG_IS_DEFAULT(G1ConcRefinementThreads)) {
1969     FLAG_SET_ERGO(uint, G1ConcRefinementThreads, ParallelGCThreads);
1970   }
1971 #endif
1972 
1973   // MarkStackSize will be set (if it hasn't been set by the user)
1974   // when concurrent marking is initialized.
1975   // Its value will be based upon the number of parallel marking threads.
1976   // But we do set the maximum mark stack size here.
1977   if (FLAG_IS_DEFAULT(MarkStackSizeMax)) {
1978     FLAG_SET_DEFAULT(MarkStackSizeMax, 128 * TASKQUEUE_SIZE);
1979   }
1980 
1981   if (FLAG_IS_DEFAULT(GCTimeRatio) || GCTimeRatio == 0) {
1982     // In G1, we want the default GC overhead goal to be higher than
1983     // it is for PS, or the heap might be expanded too aggressively.
1984     // We set it here to ~8%.
1985     FLAG_SET_DEFAULT(GCTimeRatio, 12);
1986   }
1987 
1988   // Below, we might need to calculate the pause time interval based on
1989   // the pause target. When we do so we are going to give G1 maximum
1990   // flexibility and allow it to do pauses when it needs to. So, we'll
1991   // arrange that the pause interval to be pause time target + 1 to
1992   // ensure that a) the pause time target is maximized with respect to
1993   // the pause interval and b) we maintain the invariant that pause
1994   // time target < pause interval. If the user does not want this
1995   // maximum flexibility, they will have to set the pause interval
1996   // explicitly.
1997 
1998   if (FLAG_IS_DEFAULT(MaxGCPauseMillis)) {
1999     // The default pause time target in G1 is 200ms
2000     FLAG_SET_DEFAULT(MaxGCPauseMillis, 200);
2001   }
2002 
2003   // Then, if the interval parameter was not set, set it according to
2004   // the pause time target (this will also deal with the case when the
2005   // pause time target is the default value).
2006   if (FLAG_IS_DEFAULT(GCPauseIntervalMillis)) {
2007     FLAG_SET_DEFAULT(GCPauseIntervalMillis, MaxGCPauseMillis + 1);
2008   }
2009 
2010   log_trace(gc)("MarkStackSize: %uk  MarkStackSizeMax: %uk", (unsigned int) (MarkStackSize / K), (uint) (MarkStackSizeMax / K));
2011 }
2012 
2013 void Arguments::set_gc_specific_flags() {
2014 #if INCLUDE_ALL_GCS
2015   // Set per-collector flags
2016   if (UseParallelGC || UseParallelOldGC) {
2017     set_parallel_gc_flags();
2018   } else if (UseConcMarkSweepGC) {
2019     set_cms_and_parnew_gc_flags();
2020   } else if (UseG1GC) {
2021     set_g1_gc_flags();
2022   }
2023   if (AssumeMP && !UseSerialGC) {
2024     if (FLAG_IS_DEFAULT(ParallelGCThreads) && ParallelGCThreads == 1) {
2025       warning("If the number of processors is expected to increase from one, then"
2026               " you should configure the number of parallel GC threads appropriately"
2027               " using -XX:ParallelGCThreads=N");
2028     }
2029   }
2030   if (MinHeapFreeRatio == 100) {
2031     // Keeping the heap 100% free is hard ;-) so limit it to 99%.
2032     FLAG_SET_ERGO(uintx, MinHeapFreeRatio, 99);
2033   }
2034 
2035   // If class unloading is disabled, also disable concurrent class unloading.
2036   if (!ClassUnloading) {
2037     FLAG_SET_CMDLINE(bool, CMSClassUnloadingEnabled, false);
2038     FLAG_SET_CMDLINE(bool, ClassUnloadingWithConcurrentMark, false);
2039   }
2040 #endif // INCLUDE_ALL_GCS
2041 }
2042 
2043 julong Arguments::limit_by_allocatable_memory(julong limit) {
2044   julong max_allocatable;
2045   julong result = limit;
2046   if (os::has_allocatable_memory_limit(&max_allocatable)) {
2047     result = MIN2(result, max_allocatable / MaxVirtMemFraction);
2048   }
2049   return result;
2050 }
2051 
2052 // Use static initialization to get the default before parsing
2053 static const size_t DefaultHeapBaseMinAddress = HeapBaseMinAddress;
2054 
2055 void Arguments::set_heap_size() {
2056   julong phys_mem =
2057     FLAG_IS_DEFAULT(MaxRAM) ? MIN2(os::physical_memory(), (julong)MaxRAM)
2058                             : (julong)MaxRAM;
2059 
2060   // Experimental support for CGroup memory limits
2061   if (UseCGroupMemoryLimitForHeap) {
2062     // This is a rough indicator that a CGroup limit may be in force
2063     // for this process
2064     const char* lim_file = "/sys/fs/cgroup/memory/memory.limit_in_bytes";
2065     FILE *fp = fopen(lim_file, "r");
2066     if (fp != NULL) {
2067       julong cgroup_max = 0;
2068       int ret = fscanf(fp, JULONG_FORMAT, &cgroup_max);
2069       if (ret == 1 && cgroup_max > 0) {
2070         // If unlimited, cgroup_max will be a very large, but unspecified
2071         // value, so use initial phys_mem as a limit
2072         log_info(gc, heap)("Setting phys_mem to the min of cgroup limit ("
2073                            JULONG_FORMAT "MB) and initial phys_mem ("
2074                            JULONG_FORMAT "MB)", cgroup_max/M, phys_mem/M);
2075         phys_mem = MIN2(cgroup_max, phys_mem);
2076       } else {
2077         warning("Unable to read/parse cgroup memory limit from %s: %s",
2078                 lim_file, errno != 0 ? strerror(errno) : "unknown error");
2079       }
2080       fclose(fp);
2081     } else {
2082       warning("Unable to open cgroup memory limit file %s (%s)", lim_file, strerror(errno));
2083     }
2084   }
2085 
2086   // Convert deprecated flags
2087   if (FLAG_IS_DEFAULT(MaxRAMPercentage) &&
2088       !FLAG_IS_DEFAULT(MaxRAMFraction))
2089     MaxRAMPercentage = 100.0 / MaxRAMFraction;
2090 
2091   if (FLAG_IS_DEFAULT(MinRAMPercentage) &&
2092       !FLAG_IS_DEFAULT(MinRAMFraction))
2093     MinRAMPercentage = 100.0 / MinRAMFraction;
2094 
2095   if (FLAG_IS_DEFAULT(InitialRAMPercentage) &&
2096       !FLAG_IS_DEFAULT(InitialRAMFraction))
2097     InitialRAMPercentage = 100.0 / InitialRAMFraction;
2098 
2099   // If the maximum heap size has not been set with -Xmx,
2100   // then set it as fraction of the size of physical memory,
2101   // respecting the maximum and minimum sizes of the heap.
2102   if (FLAG_IS_DEFAULT(MaxHeapSize)) {
2103     julong reasonable_max = (julong)((phys_mem * MaxRAMPercentage) / 100);
2104     if (phys_mem <= (julong)((MaxHeapSize * MinRAMPercentage) / 100)) {
2105       // Small physical memory, so use a minimum fraction of it for the heap
2106       reasonable_max = (julong)((phys_mem * MinRAMPercentage) / 100);
2107     } else {
2108       // Not-small physical memory, so require a heap at least
2109       // as large as MaxHeapSize
2110       reasonable_max = MAX2(reasonable_max, (julong)MaxHeapSize);
2111     }
2112 
2113     if (!FLAG_IS_DEFAULT(ErgoHeapSizeLimit) && ErgoHeapSizeLimit != 0) {
2114       // Limit the heap size to ErgoHeapSizeLimit
2115       reasonable_max = MIN2(reasonable_max, (julong)ErgoHeapSizeLimit);
2116     }
2117     if (UseCompressedOops) {
2118       // Limit the heap size to the maximum possible when using compressed oops
2119       julong max_coop_heap = (julong)max_heap_for_compressed_oops();
2120 
2121       // HeapBaseMinAddress can be greater than default but not less than.
2122       if (!FLAG_IS_DEFAULT(HeapBaseMinAddress)) {
2123         if (HeapBaseMinAddress < DefaultHeapBaseMinAddress) {
2124           // matches compressed oops printing flags
2125           log_debug(gc, heap, coops)("HeapBaseMinAddress must be at least " SIZE_FORMAT
2126                                      " (" SIZE_FORMAT "G) which is greater than value given " SIZE_FORMAT,
2127                                      DefaultHeapBaseMinAddress,
2128                                      DefaultHeapBaseMinAddress/G,
2129                                      HeapBaseMinAddress);
2130           FLAG_SET_ERGO(size_t, HeapBaseMinAddress, DefaultHeapBaseMinAddress);
2131         }
2132       }
2133 
2134       if (HeapBaseMinAddress + MaxHeapSize < max_coop_heap) {
2135         // Heap should be above HeapBaseMinAddress to get zero based compressed oops
2136         // but it should be not less than default MaxHeapSize.
2137         max_coop_heap -= HeapBaseMinAddress;
2138       }
2139       reasonable_max = MIN2(reasonable_max, max_coop_heap);
2140     }
2141     reasonable_max = limit_by_allocatable_memory(reasonable_max);
2142 
2143     if (!FLAG_IS_DEFAULT(InitialHeapSize)) {
2144       // An initial heap size was specified on the command line,
2145       // so be sure that the maximum size is consistent.  Done
2146       // after call to limit_by_allocatable_memory because that
2147       // method might reduce the allocation size.
2148       reasonable_max = MAX2(reasonable_max, (julong)InitialHeapSize);
2149     }
2150 
2151     log_trace(gc, heap)("  Maximum heap size " SIZE_FORMAT, (size_t) reasonable_max);
2152     FLAG_SET_ERGO(size_t, MaxHeapSize, (size_t)reasonable_max);
2153   }
2154 
2155   // If the minimum or initial heap_size have not been set or requested to be set
2156   // ergonomically, set them accordingly.
2157   if (InitialHeapSize == 0 || min_heap_size() == 0) {
2158     julong reasonable_minimum = (julong)(OldSize + NewSize);
2159 
2160     reasonable_minimum = MIN2(reasonable_minimum, (julong)MaxHeapSize);
2161 
2162     reasonable_minimum = limit_by_allocatable_memory(reasonable_minimum);
2163 
2164     if (InitialHeapSize == 0) {
2165       julong reasonable_initial = (julong)((phys_mem * InitialRAMPercentage) / 100);
2166 
2167       reasonable_initial = MAX3(reasonable_initial, reasonable_minimum, (julong)min_heap_size());
2168       reasonable_initial = MIN2(reasonable_initial, (julong)MaxHeapSize);
2169 
2170       reasonable_initial = limit_by_allocatable_memory(reasonable_initial);
2171 
2172       log_trace(gc, heap)("  Initial heap size " SIZE_FORMAT, (size_t)reasonable_initial);
2173       FLAG_SET_ERGO(size_t, InitialHeapSize, (size_t)reasonable_initial);
2174     }
2175     // If the minimum heap size has not been set (via -Xms),
2176     // synchronize with InitialHeapSize to avoid errors with the default value.
2177     if (min_heap_size() == 0) {
2178       set_min_heap_size(MIN2((size_t)reasonable_minimum, InitialHeapSize));
2179       log_trace(gc, heap)("  Minimum heap size " SIZE_FORMAT, min_heap_size());
2180     }
2181   }
2182 }
2183 
2184 // This option inspects the machine and attempts to set various
2185 // parameters to be optimal for long-running, memory allocation
2186 // intensive jobs.  It is intended for machines with large
2187 // amounts of cpu and memory.
2188 jint Arguments::set_aggressive_heap_flags() {
2189   // initHeapSize is needed since _initial_heap_size is 4 bytes on a 32 bit
2190   // VM, but we may not be able to represent the total physical memory
2191   // available (like having 8gb of memory on a box but using a 32bit VM).
2192   // Thus, we need to make sure we're using a julong for intermediate
2193   // calculations.
2194   julong initHeapSize;
2195   julong total_memory = os::physical_memory();
2196 
2197   if (total_memory < (julong) 256 * M) {
2198     jio_fprintf(defaultStream::error_stream(),
2199             "You need at least 256mb of memory to use -XX:+AggressiveHeap\n");
2200     vm_exit(1);
2201   }
2202 
2203   // The heap size is half of available memory, or (at most)
2204   // all of possible memory less 160mb (leaving room for the OS
2205   // when using ISM).  This is the maximum; because adaptive sizing
2206   // is turned on below, the actual space used may be smaller.
2207 
2208   initHeapSize = MIN2(total_memory / (julong) 2,
2209           total_memory - (julong) 160 * M);
2210 
2211   initHeapSize = limit_by_allocatable_memory(initHeapSize);
2212 
2213   if (FLAG_IS_DEFAULT(MaxHeapSize)) {
2214     if (FLAG_SET_CMDLINE(size_t, MaxHeapSize, initHeapSize) != Flag::SUCCESS) {
2215       return JNI_EINVAL;
2216     }
2217     if (FLAG_SET_CMDLINE(size_t, InitialHeapSize, initHeapSize) != Flag::SUCCESS) {
2218       return JNI_EINVAL;
2219     }
2220     // Currently the minimum size and the initial heap sizes are the same.
2221     set_min_heap_size(initHeapSize);
2222   }
2223   if (FLAG_IS_DEFAULT(NewSize)) {
2224     // Make the young generation 3/8ths of the total heap.
2225     if (FLAG_SET_CMDLINE(size_t, NewSize,
2226             ((julong) MaxHeapSize / (julong) 8) * (julong) 3) != Flag::SUCCESS) {
2227       return JNI_EINVAL;
2228     }
2229     if (FLAG_SET_CMDLINE(size_t, MaxNewSize, NewSize) != Flag::SUCCESS) {
2230       return JNI_EINVAL;
2231     }
2232   }
2233 
2234 #if !defined(_ALLBSD_SOURCE) && !defined(AIX)  // UseLargePages is not yet supported on BSD and AIX.
2235   FLAG_SET_DEFAULT(UseLargePages, true);
2236 #endif
2237 
2238   // Increase some data structure sizes for efficiency
2239   if (FLAG_SET_CMDLINE(size_t, BaseFootPrintEstimate, MaxHeapSize) != Flag::SUCCESS) {
2240     return JNI_EINVAL;
2241   }
2242   if (FLAG_SET_CMDLINE(bool, ResizeTLAB, false) != Flag::SUCCESS) {
2243     return JNI_EINVAL;
2244   }
2245   if (FLAG_SET_CMDLINE(size_t, TLABSize, 256 * K) != Flag::SUCCESS) {
2246     return JNI_EINVAL;
2247   }
2248 
2249   // See the OldPLABSize comment below, but replace 'after promotion'
2250   // with 'after copying'.  YoungPLABSize is the size of the survivor
2251   // space per-gc-thread buffers.  The default is 4kw.
2252   if (FLAG_SET_CMDLINE(size_t, YoungPLABSize, 256 * K) != Flag::SUCCESS) { // Note: this is in words
2253     return JNI_EINVAL;
2254   }
2255 
2256   // OldPLABSize is the size of the buffers in the old gen that
2257   // UseParallelGC uses to promote live data that doesn't fit in the
2258   // survivor spaces.  At any given time, there's one for each gc thread.
2259   // The default size is 1kw. These buffers are rarely used, since the
2260   // survivor spaces are usually big enough.  For specjbb, however, there
2261   // are occasions when there's lots of live data in the young gen
2262   // and we end up promoting some of it.  We don't have a definite
2263   // explanation for why bumping OldPLABSize helps, but the theory
2264   // is that a bigger PLAB results in retaining something like the
2265   // original allocation order after promotion, which improves mutator
2266   // locality.  A minor effect may be that larger PLABs reduce the
2267   // number of PLAB allocation events during gc.  The value of 8kw
2268   // was arrived at by experimenting with specjbb.
2269   if (FLAG_SET_CMDLINE(size_t, OldPLABSize, 8 * K) != Flag::SUCCESS) { // Note: this is in words
2270     return JNI_EINVAL;
2271   }
2272 
2273   // Enable parallel GC and adaptive generation sizing
2274   if (FLAG_SET_CMDLINE(bool, UseParallelGC, true) != Flag::SUCCESS) {
2275     return JNI_EINVAL;
2276   }
2277 
2278   // Encourage steady state memory management
2279   if (FLAG_SET_CMDLINE(uintx, ThresholdTolerance, 100) != Flag::SUCCESS) {
2280     return JNI_EINVAL;
2281   }
2282 
2283   // This appears to improve mutator locality
2284   if (FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false) != Flag::SUCCESS) {
2285     return JNI_EINVAL;
2286   }
2287 
2288   // Get around early Solaris scheduling bug
2289   // (affinity vs other jobs on system)
2290   // but disallow DR and offlining (5008695).
2291   if (FLAG_SET_CMDLINE(bool, BindGCTaskThreadsToCPUs, true) != Flag::SUCCESS) {
2292     return JNI_EINVAL;
2293   }
2294 
2295   return JNI_OK;
2296 }
2297 
2298 // This must be called after ergonomics.
2299 void Arguments::set_bytecode_flags() {
2300   if (!RewriteBytecodes) {
2301     FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
2302   }
2303 }
2304 
2305 // Aggressive optimization flags  -XX:+AggressiveOpts
2306 jint Arguments::set_aggressive_opts_flags() {
2307 #ifdef COMPILER2
2308   if (AggressiveUnboxing) {
2309     if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
2310       FLAG_SET_DEFAULT(EliminateAutoBox, true);
2311     } else if (!EliminateAutoBox) {
2312       // warning("AggressiveUnboxing is disabled because EliminateAutoBox is disabled");
2313       AggressiveUnboxing = false;
2314     }
2315     if (FLAG_IS_DEFAULT(DoEscapeAnalysis)) {
2316       FLAG_SET_DEFAULT(DoEscapeAnalysis, true);
2317     } else if (!DoEscapeAnalysis) {
2318       // warning("AggressiveUnboxing is disabled because DoEscapeAnalysis is disabled");
2319       AggressiveUnboxing = false;
2320     }
2321   }
2322   if (AggressiveOpts || !FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
2323     if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
2324       FLAG_SET_DEFAULT(EliminateAutoBox, true);
2325     }
2326     if (FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
2327       FLAG_SET_DEFAULT(AutoBoxCacheMax, 20000);
2328     }
2329 
2330     // Feed the cache size setting into the JDK
2331     char buffer[1024];
2332     jio_snprintf(buffer, 1024, "java.lang.Integer.IntegerCache.high=" INTX_FORMAT, AutoBoxCacheMax);
2333     if (!add_property(buffer)) {
2334       return JNI_ENOMEM;
2335     }
2336   }
2337   if (AggressiveOpts && FLAG_IS_DEFAULT(BiasedLockingStartupDelay)) {
2338     FLAG_SET_DEFAULT(BiasedLockingStartupDelay, 500);
2339   }
2340 #endif
2341 
2342   if (AggressiveOpts) {
2343 // Sample flag setting code
2344 //    if (FLAG_IS_DEFAULT(EliminateZeroing)) {
2345 //      FLAG_SET_DEFAULT(EliminateZeroing, true);
2346 //    }
2347   }
2348 
2349   return JNI_OK;
2350 }
2351 
2352 //===========================================================================================================
2353 // Parsing of java.compiler property
2354 
2355 void Arguments::process_java_compiler_argument(const char* arg) {
2356   // For backwards compatibility, Djava.compiler=NONE or ""
2357   // causes us to switch to -Xint mode UNLESS -Xdebug
2358   // is also specified.
2359   if (strlen(arg) == 0 || strcasecmp(arg, "NONE") == 0) {
2360     set_java_compiler(true);    // "-Djava.compiler[=...]" most recently seen.
2361   }
2362 }
2363 
2364 void Arguments::process_java_launcher_argument(const char* launcher, void* extra_info) {
2365   _sun_java_launcher = os::strdup_check_oom(launcher);
2366 }
2367 
2368 bool Arguments::created_by_java_launcher() {
2369   assert(_sun_java_launcher != NULL, "property must have value");
2370   return strcmp(DEFAULT_JAVA_LAUNCHER, _sun_java_launcher) != 0;
2371 }
2372 
2373 bool Arguments::sun_java_launcher_is_altjvm() {
2374   return _sun_java_launcher_is_altjvm;
2375 }
2376 
2377 //===========================================================================================================
2378 // Parsing of main arguments
2379 
2380 #if INCLUDE_JVMCI
2381 // Check consistency of jvmci vm argument settings.
2382 bool Arguments::check_jvmci_args_consistency() {
2383    return JVMCIGlobals::check_jvmci_flags_are_consistent();
2384 }
2385 #endif //INCLUDE_JVMCI
2386 
2387 // Check consistency of GC selection
2388 bool Arguments::check_gc_consistency() {
2389   // Ensure that the user has not selected conflicting sets
2390   // of collectors.
2391   uint i = 0;
2392   if (UseSerialGC)                       i++;
2393   if (UseConcMarkSweepGC)                i++;
2394   if (UseParallelGC || UseParallelOldGC) i++;
2395   if (UseG1GC)                           i++;
2396   if (i > 1) {
2397     jio_fprintf(defaultStream::error_stream(),
2398                 "Conflicting collector combinations in option list; "
2399                 "please refer to the release notes for the combinations "
2400                 "allowed\n");
2401     return false;
2402   }
2403 
2404   return true;
2405 }
2406 
2407 // Check the consistency of vm_init_args
2408 bool Arguments::check_vm_args_consistency() {
2409   // Method for adding checks for flag consistency.
2410   // The intent is to warn the user of all possible conflicts,
2411   // before returning an error.
2412   // Note: Needs platform-dependent factoring.
2413   bool status = true;
2414 
2415   if (TLABRefillWasteFraction == 0) {
2416     jio_fprintf(defaultStream::error_stream(),
2417                 "TLABRefillWasteFraction should be a denominator, "
2418                 "not " SIZE_FORMAT "\n",
2419                 TLABRefillWasteFraction);
2420     status = false;
2421   }
2422 
2423   if (FullGCALot && FLAG_IS_DEFAULT(MarkSweepAlwaysCompactCount)) {
2424     MarkSweepAlwaysCompactCount = 1;  // Move objects every gc.
2425   }
2426 
2427   if (!(UseParallelGC || UseParallelOldGC) && FLAG_IS_DEFAULT(ScavengeBeforeFullGC)) {
2428     FLAG_SET_DEFAULT(ScavengeBeforeFullGC, false);
2429   }
2430 
2431   if (GCTimeLimit == 100) {
2432     // Turn off gc-overhead-limit-exceeded checks
2433     FLAG_SET_DEFAULT(UseGCOverheadLimit, false);
2434   }
2435 
2436   status = status && check_gc_consistency();
2437 
2438   // CMS space iteration, which FLSVerifyAllHeapreferences entails,
2439   // insists that we hold the requisite locks so that the iteration is
2440   // MT-safe. For the verification at start-up and shut-down, we don't
2441   // yet have a good way of acquiring and releasing these locks,
2442   // which are not visible at the CollectedHeap level. We want to
2443   // be able to acquire these locks and then do the iteration rather
2444   // than just disable the lock verification. This will be fixed under
2445   // bug 4788986.
2446   if (UseConcMarkSweepGC && FLSVerifyAllHeapReferences) {
2447     if (VerifyDuringStartup) {
2448       warning("Heap verification at start-up disabled "
2449               "(due to current incompatibility with FLSVerifyAllHeapReferences)");
2450       VerifyDuringStartup = false; // Disable verification at start-up
2451     }
2452 
2453     if (VerifyBeforeExit) {
2454       warning("Heap verification at shutdown disabled "
2455               "(due to current incompatibility with FLSVerifyAllHeapReferences)");
2456       VerifyBeforeExit = false; // Disable verification at shutdown
2457     }
2458   }
2459 
2460   if (PrintNMTStatistics) {
2461 #if INCLUDE_NMT
2462     if (MemTracker::tracking_level() == NMT_off) {
2463 #endif // INCLUDE_NMT
2464       warning("PrintNMTStatistics is disabled, because native memory tracking is not enabled");
2465       PrintNMTStatistics = false;
2466 #if INCLUDE_NMT
2467     }
2468 #endif
2469   }
2470 
2471 #if INCLUDE_JVMCI
2472   status = status && check_jvmci_args_consistency();
2473 
2474   if (EnableJVMCI) {
2475     PropertyList_unique_add(&_system_properties, "jdk.internal.vm.ci.enabled", "true",
2476         AddProperty, UnwriteableProperty, InternalProperty);
2477 
2478     if (!ScavengeRootsInCode) {
2479       warning("forcing ScavengeRootsInCode non-zero because JVMCI is enabled");
2480       ScavengeRootsInCode = 1;
2481     }
2482   }
2483 #endif
2484 
2485   // Check lower bounds of the code cache
2486   // Template Interpreter code is approximately 3X larger in debug builds.
2487   uint min_code_cache_size = CodeCacheMinimumUseSpace DEBUG_ONLY(* 3);
2488   if (InitialCodeCacheSize < (uintx)os::vm_page_size()) {
2489     jio_fprintf(defaultStream::error_stream(),
2490                 "Invalid InitialCodeCacheSize=%dK. Must be at least %dK.\n", InitialCodeCacheSize/K,
2491                 os::vm_page_size()/K);
2492     status = false;
2493   } else if (ReservedCodeCacheSize < InitialCodeCacheSize) {
2494     jio_fprintf(defaultStream::error_stream(),
2495                 "Invalid ReservedCodeCacheSize: %dK. Must be at least InitialCodeCacheSize=%dK.\n",
2496                 ReservedCodeCacheSize/K, InitialCodeCacheSize/K);
2497     status = false;
2498   } else if (ReservedCodeCacheSize < min_code_cache_size) {
2499     jio_fprintf(defaultStream::error_stream(),
2500                 "Invalid ReservedCodeCacheSize=%dK. Must be at least %uK.\n", ReservedCodeCacheSize/K,
2501                 min_code_cache_size/K);
2502     status = false;
2503   } else if (ReservedCodeCacheSize > CODE_CACHE_SIZE_LIMIT) {
2504     // Code cache size larger than CODE_CACHE_SIZE_LIMIT is not supported.
2505     jio_fprintf(defaultStream::error_stream(),
2506                 "Invalid ReservedCodeCacheSize=%dM. Must be at most %uM.\n", ReservedCodeCacheSize/M,
2507                 CODE_CACHE_SIZE_LIMIT/M);
2508     status = false;
2509   } else if (NonNMethodCodeHeapSize < min_code_cache_size) {
2510     jio_fprintf(defaultStream::error_stream(),
2511                 "Invalid NonNMethodCodeHeapSize=%dK. Must be at least %uK.\n", NonNMethodCodeHeapSize/K,
2512                 min_code_cache_size/K);
2513     status = false;
2514   }
2515 
2516 #ifdef _LP64
2517   if (!FLAG_IS_DEFAULT(CICompilerCount) && !FLAG_IS_DEFAULT(CICompilerCountPerCPU) && CICompilerCountPerCPU) {
2518     warning("The VM option CICompilerCountPerCPU overrides CICompilerCount.");
2519   }
2520 #endif
2521 
2522 #ifndef SUPPORT_RESERVED_STACK_AREA
2523   if (StackReservedPages != 0) {
2524     FLAG_SET_CMDLINE(intx, StackReservedPages, 0);
2525     warning("Reserved Stack Area not supported on this platform");
2526   }
2527 #endif
2528 
2529   if (BackgroundCompilation && (CompileTheWorld || ReplayCompiles)) {
2530     if (!FLAG_IS_DEFAULT(BackgroundCompilation)) {
2531       warning("BackgroundCompilation disabled due to CompileTheWorld or ReplayCompiles options.");
2532     }
2533     FLAG_SET_CMDLINE(bool, BackgroundCompilation, false);
2534   }
2535   if (UseCompiler && is_interpreter_only()) {
2536     if (!FLAG_IS_DEFAULT(UseCompiler)) {
2537       warning("UseCompiler disabled due to -Xint.");
2538     }
2539     FLAG_SET_CMDLINE(bool, UseCompiler, false);
2540   }
2541 #ifdef COMPILER2
2542   if (PostLoopMultiversioning && !RangeCheckElimination) {
2543     if (!FLAG_IS_DEFAULT(PostLoopMultiversioning)) {
2544       warning("PostLoopMultiversioning disabled because RangeCheckElimination is disabled.");
2545     }
2546     FLAG_SET_CMDLINE(bool, PostLoopMultiversioning, false);
2547   }
2548 #endif
2549   return status;
2550 }
2551 
2552 bool Arguments::is_bad_option(const JavaVMOption* option, jboolean ignore,
2553   const char* option_type) {
2554   if (ignore) return false;
2555 
2556   const char* spacer = " ";
2557   if (option_type == NULL) {
2558     option_type = ++spacer; // Set both to the empty string.
2559   }
2560 
2561   if (os::obsolete_option(option)) {
2562     jio_fprintf(defaultStream::error_stream(),
2563                 "Obsolete %s%soption: %s\n", option_type, spacer,
2564       option->optionString);
2565     return false;
2566   } else {
2567     jio_fprintf(defaultStream::error_stream(),
2568                 "Unrecognized %s%soption: %s\n", option_type, spacer,
2569       option->optionString);
2570     return true;
2571   }
2572 }
2573 
2574 static const char* user_assertion_options[] = {
2575   "-da", "-ea", "-disableassertions", "-enableassertions", 0
2576 };
2577 
2578 static const char* system_assertion_options[] = {
2579   "-dsa", "-esa", "-disablesystemassertions", "-enablesystemassertions", 0
2580 };
2581 
2582 bool Arguments::parse_uintx(const char* value,
2583                             uintx* uintx_arg,
2584                             uintx min_size) {
2585 
2586   // Check the sign first since atojulong() parses only unsigned values.
2587   bool value_is_positive = !(*value == '-');
2588 
2589   if (value_is_positive) {
2590     julong n;
2591     bool good_return = atojulong(value, &n);
2592     if (good_return) {
2593       bool above_minimum = n >= min_size;
2594       bool value_is_too_large = n > max_uintx;
2595 
2596       if (above_minimum && !value_is_too_large) {
2597         *uintx_arg = n;
2598         return true;
2599       }
2600     }
2601   }
2602   return false;
2603 }
2604 
2605 unsigned int addreads_count = 0;
2606 unsigned int addexports_count = 0;
2607 unsigned int addopens_count = 0;
2608 unsigned int addmods_count = 0;
2609 unsigned int patch_mod_count = 0;
2610 
2611 bool Arguments::create_property(const char* prop_name, const char* prop_value, PropertyInternal internal) {
2612   size_t prop_len = strlen(prop_name) + strlen(prop_value) + 2;
2613   char* property = AllocateHeap(prop_len, mtArguments);
2614   int ret = jio_snprintf(property, prop_len, "%s=%s", prop_name, prop_value);
2615   if (ret < 0 || ret >= (int)prop_len) {
2616     FreeHeap(property);
2617     return false;
2618   }
2619   bool added = add_property(property, UnwriteableProperty, internal);
2620   FreeHeap(property);
2621   return added;
2622 }
2623 
2624 bool Arguments::create_numbered_property(const char* prop_base_name, const char* prop_value, unsigned int count) {
2625   const unsigned int props_count_limit = 1000;
2626   const int max_digits = 3;
2627   const int extra_symbols_count = 3; // includes '.', '=', '\0'
2628 
2629   // Make sure count is < props_count_limit. Otherwise, memory allocation will be too small.
2630   if (count < props_count_limit) {
2631     size_t prop_len = strlen(prop_base_name) + strlen(prop_value) + max_digits + extra_symbols_count;
2632     char* property = AllocateHeap(prop_len, mtArguments);
2633     int ret = jio_snprintf(property, prop_len, "%s.%d=%s", prop_base_name, count, prop_value);
2634     if (ret < 0 || ret >= (int)prop_len) {
2635       FreeHeap(property);
2636       jio_fprintf(defaultStream::error_stream(), "Failed to create property %s.%d=%s\n", prop_base_name, count, prop_value);
2637       return false;
2638     }
2639     bool added = add_property(property, UnwriteableProperty, InternalProperty);
2640     FreeHeap(property);
2641     return added;
2642   }
2643 
2644   jio_fprintf(defaultStream::error_stream(), "Property count limit exceeded: %s, limit=%d\n", prop_base_name, props_count_limit);
2645   return false;
2646 }
2647 
2648 Arguments::ArgsRange Arguments::parse_memory_size(const char* s,
2649                                                   julong* long_arg,
2650                                                   julong min_size,
2651                                                   julong max_size) {
2652   if (!atojulong(s, long_arg)) return arg_unreadable;
2653   return check_memory_size(*long_arg, min_size, max_size);
2654 }
2655 
2656 // Parse JavaVMInitArgs structure
2657 
2658 jint Arguments::parse_vm_init_args(const JavaVMInitArgs *java_tool_options_args,
2659                                    const JavaVMInitArgs *java_options_args,
2660                                    const JavaVMInitArgs *cmd_line_args) {
2661   bool patch_mod_javabase = false;
2662 
2663   // Save default settings for some mode flags
2664   Arguments::_AlwaysCompileLoopMethods = AlwaysCompileLoopMethods;
2665   Arguments::_UseOnStackReplacement    = UseOnStackReplacement;
2666   Arguments::_ClipInlining             = ClipInlining;
2667   Arguments::_BackgroundCompilation    = BackgroundCompilation;
2668   if (TieredCompilation) {
2669     Arguments::_Tier3InvokeNotifyFreqLog = Tier3InvokeNotifyFreqLog;
2670     Arguments::_Tier4InvocationThreshold = Tier4InvocationThreshold;
2671   }
2672 
2673   // Setup flags for mixed which is the default
2674   set_mode_flags(_mixed);
2675 
2676   // Parse args structure generated from JAVA_TOOL_OPTIONS environment
2677   // variable (if present).
2678   jint result = parse_each_vm_init_arg(java_tool_options_args, &patch_mod_javabase, Flag::ENVIRON_VAR);
2679   if (result != JNI_OK) {
2680     return result;
2681   }
2682 
2683   // Parse args structure generated from the command line flags.
2684   result = parse_each_vm_init_arg(cmd_line_args, &patch_mod_javabase, Flag::COMMAND_LINE);
2685   if (result != JNI_OK) {
2686     return result;
2687   }
2688 
2689   // Parse args structure generated from the _JAVA_OPTIONS environment
2690   // variable (if present) (mimics classic VM)
2691   result = parse_each_vm_init_arg(java_options_args, &patch_mod_javabase, Flag::ENVIRON_VAR);
2692   if (result != JNI_OK) {
2693     return result;
2694   }
2695 
2696   // Do final processing now that all arguments have been parsed
2697   result = finalize_vm_init_args(patch_mod_javabase);
2698   if (result != JNI_OK) {
2699     return result;
2700   }
2701 
2702   return JNI_OK;
2703 }
2704 
2705 // Checks if name in command-line argument -agent{lib,path}:name[=options]
2706 // represents a valid JDWP agent.  is_path==true denotes that we
2707 // are dealing with -agentpath (case where name is a path), otherwise with
2708 // -agentlib
2709 bool valid_jdwp_agent(char *name, bool is_path) {
2710   char *_name;
2711   const char *_jdwp = "jdwp";
2712   size_t _len_jdwp, _len_prefix;
2713 
2714   if (is_path) {
2715     if ((_name = strrchr(name, (int) *os::file_separator())) == NULL) {
2716       return false;
2717     }
2718 
2719     _name++;  // skip past last path separator
2720     _len_prefix = strlen(JNI_LIB_PREFIX);
2721 
2722     if (strncmp(_name, JNI_LIB_PREFIX, _len_prefix) != 0) {
2723       return false;
2724     }
2725 
2726     _name += _len_prefix;
2727     _len_jdwp = strlen(_jdwp);
2728 
2729     if (strncmp(_name, _jdwp, _len_jdwp) == 0) {
2730       _name += _len_jdwp;
2731     }
2732     else {
2733       return false;
2734     }
2735 
2736     if (strcmp(_name, JNI_LIB_SUFFIX) != 0) {
2737       return false;
2738     }
2739 
2740     return true;
2741   }
2742 
2743   if (strcmp(name, _jdwp) == 0) {
2744     return true;
2745   }
2746 
2747   return false;
2748 }
2749 
2750 int Arguments::process_patch_mod_option(const char* patch_mod_tail, bool* patch_mod_javabase) {
2751   // --patch-module=<module>=<file>(<pathsep><file>)*
2752   assert(patch_mod_tail != NULL, "Unexpected NULL patch-module value");
2753   // Find the equal sign between the module name and the path specification
2754   const char* module_equal = strchr(patch_mod_tail, '=');
2755   if (module_equal == NULL) {
2756     jio_fprintf(defaultStream::output_stream(), "Missing '=' in --patch-module specification\n");
2757     return JNI_ERR;
2758   } else {
2759     // Pick out the module name
2760     size_t module_len = module_equal - patch_mod_tail;
2761     char* module_name = NEW_C_HEAP_ARRAY_RETURN_NULL(char, module_len+1, mtArguments);
2762     if (module_name != NULL) {
2763       memcpy(module_name, patch_mod_tail, module_len);
2764       *(module_name + module_len) = '\0';
2765       // The path piece begins one past the module_equal sign
2766       add_patch_mod_prefix(module_name, module_equal + 1, patch_mod_javabase);
2767       FREE_C_HEAP_ARRAY(char, module_name);
2768       if (!create_numbered_property("jdk.module.patch", patch_mod_tail, patch_mod_count++)) {
2769         return JNI_ENOMEM;
2770       }
2771     } else {
2772       return JNI_ENOMEM;
2773     }
2774   }
2775   return JNI_OK;
2776 }
2777 
2778 // Parse -Xss memory string parameter and convert to ThreadStackSize in K.
2779 jint Arguments::parse_xss(const JavaVMOption* option, const char* tail, intx* out_ThreadStackSize) {
2780   // The min and max sizes match the values in globals.hpp, but scaled
2781   // with K. The values have been chosen so that alignment with page
2782   // size doesn't change the max value, which makes the conversions
2783   // back and forth between Xss value and ThreadStackSize value easier.
2784   // The values have also been chosen to fit inside a 32-bit signed type.
2785   const julong min_ThreadStackSize = 0;
2786   const julong max_ThreadStackSize = 1 * M;
2787 
2788   const julong min_size = min_ThreadStackSize * K;
2789   const julong max_size = max_ThreadStackSize * K;
2790 
2791   assert(is_aligned(max_size, os::vm_page_size()), "Implementation assumption");
2792 
2793   julong size = 0;
2794   ArgsRange errcode = parse_memory_size(tail, &size, min_size, max_size);
2795   if (errcode != arg_in_range) {
2796     bool silent = (option == NULL); // Allow testing to silence error messages
2797     if (!silent) {
2798       jio_fprintf(defaultStream::error_stream(),
2799                   "Invalid thread stack size: %s\n", option->optionString);
2800       describe_range_error(errcode);
2801     }
2802     return JNI_EINVAL;
2803   }
2804 
2805   // Internally track ThreadStackSize in units of 1024 bytes.
2806   const julong size_aligned = align_up(size, K);
2807   assert(size <= size_aligned,
2808          "Overflow: " JULONG_FORMAT " " JULONG_FORMAT,
2809          size, size_aligned);
2810 
2811   const julong size_in_K = size_aligned / K;
2812   assert(size_in_K < (julong)max_intx,
2813          "size_in_K doesn't fit in the type of ThreadStackSize: " JULONG_FORMAT,
2814          size_in_K);
2815 
2816   // Check that code expanding ThreadStackSize to a page aligned number of bytes won't overflow.
2817   const julong max_expanded = align_up(size_in_K * K, os::vm_page_size());
2818   assert(max_expanded < max_uintx && max_expanded >= size_in_K,
2819          "Expansion overflowed: " JULONG_FORMAT " " JULONG_FORMAT,
2820          max_expanded, size_in_K);
2821 
2822   *out_ThreadStackSize = (intx)size_in_K;
2823 
2824   return JNI_OK;
2825 }
2826 
2827 jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args, bool* patch_mod_javabase, Flag::Flags origin) {
2828   // For match_option to return remaining or value part of option string
2829   const char* tail;
2830 
2831   // iterate over arguments
2832   for (int index = 0; index < args->nOptions; index++) {
2833     bool is_absolute_path = false;  // for -agentpath vs -agentlib
2834 
2835     const JavaVMOption* option = args->options + index;
2836 
2837     if (!match_option(option, "-Djava.class.path", &tail) &&
2838         !match_option(option, "-Dsun.java.command", &tail) &&
2839         !match_option(option, "-Dsun.java.launcher", &tail)) {
2840 
2841         // add all jvm options to the jvm_args string. This string
2842         // is used later to set the java.vm.args PerfData string constant.
2843         // the -Djava.class.path and the -Dsun.java.command options are
2844         // omitted from jvm_args string as each have their own PerfData
2845         // string constant object.
2846         build_jvm_args(option->optionString);
2847     }
2848 
2849     // -verbose:[class/module/gc/jni]
2850     if (match_option(option, "-verbose", &tail)) {
2851       if (!strcmp(tail, ":class") || !strcmp(tail, "")) {
2852         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(class, load));
2853         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(class, unload));
2854       } else if (!strcmp(tail, ":module")) {
2855         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(module, load));
2856         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(module, unload));
2857       } else if (!strcmp(tail, ":gc")) {
2858         LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(gc));
2859       } else if (!strcmp(tail, ":jni")) {
2860         if (FLAG_SET_CMDLINE(bool, PrintJNIResolving, true) != Flag::SUCCESS) {
2861           return JNI_EINVAL;
2862         }
2863       }
2864     // -da / -ea / -disableassertions / -enableassertions
2865     // These accept an optional class/package name separated by a colon, e.g.,
2866     // -da:java.lang.Thread.
2867     } else if (match_option(option, user_assertion_options, &tail, true)) {
2868       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2869       if (*tail == '\0') {
2870         JavaAssertions::setUserClassDefault(enable);
2871       } else {
2872         assert(*tail == ':', "bogus match by match_option()");
2873         JavaAssertions::addOption(tail + 1, enable);
2874       }
2875     // -dsa / -esa / -disablesystemassertions / -enablesystemassertions
2876     } else if (match_option(option, system_assertion_options, &tail, false)) {
2877       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2878       JavaAssertions::setSystemClassDefault(enable);
2879     // -bootclasspath:
2880     } else if (match_option(option, "-Xbootclasspath:", &tail)) {
2881         jio_fprintf(defaultStream::output_stream(),
2882           "-Xbootclasspath is no longer a supported option.\n");
2883         return JNI_EINVAL;
2884     // -bootclasspath/a:
2885     } else if (match_option(option, "-Xbootclasspath/a:", &tail)) {
2886       Arguments::append_sysclasspath(tail);
2887     // -bootclasspath/p:
2888     } else if (match_option(option, "-Xbootclasspath/p:", &tail)) {
2889         jio_fprintf(defaultStream::output_stream(),
2890           "-Xbootclasspath/p is no longer a supported option.\n");
2891         return JNI_EINVAL;
2892     // -Xrun
2893     } else if (match_option(option, "-Xrun", &tail)) {
2894       if (tail != NULL) {
2895         const char* pos = strchr(tail, ':');
2896         size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
2897         char* name = NEW_C_HEAP_ARRAY(char, len + 1, mtArguments);
2898         jio_snprintf(name, len + 1, "%s", tail);
2899 
2900         char *options = NULL;
2901         if(pos != NULL) {
2902           size_t len2 = strlen(pos+1) + 1; // options start after ':'.  Final zero must be copied.
2903           options = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len2, mtArguments), pos+1, len2);
2904         }
2905 #if !INCLUDE_JVMTI
2906         if (strcmp(name, "jdwp") == 0) {
2907           jio_fprintf(defaultStream::error_stream(),
2908             "Debugging agents are not supported in this VM\n");
2909           return JNI_ERR;
2910         }
2911 #endif // !INCLUDE_JVMTI
2912         add_init_library(name, options);
2913       }
2914     } else if (match_option(option, "--add-reads=", &tail)) {
2915       if (!create_numbered_property("jdk.module.addreads", tail, addreads_count++)) {
2916         return JNI_ENOMEM;
2917       }
2918     } else if (match_option(option, "--add-exports=", &tail)) {
2919       if (!create_numbered_property("jdk.module.addexports", tail, addexports_count++)) {
2920         return JNI_ENOMEM;
2921       }
2922     } else if (match_option(option, "--add-opens=", &tail)) {
2923       if (!create_numbered_property("jdk.module.addopens", tail, addopens_count++)) {
2924         return JNI_ENOMEM;
2925       }
2926     } else if (match_option(option, "--add-modules=", &tail)) {
2927       if (!create_numbered_property("jdk.module.addmods", tail, addmods_count++)) {
2928         return JNI_ENOMEM;
2929       }
2930     } else if (match_option(option, "--limit-modules=", &tail)) {
2931       if (!create_property("jdk.module.limitmods", tail, InternalProperty)) {
2932         return JNI_ENOMEM;
2933       }
2934     } else if (match_option(option, "--module-path=", &tail)) {
2935       if (!create_property("jdk.module.path", tail, ExternalProperty)) {
2936         return JNI_ENOMEM;
2937       }
2938     } else if (match_option(option, "--upgrade-module-path=", &tail)) {
2939       if (!create_property("jdk.module.upgrade.path", tail, ExternalProperty)) {
2940         return JNI_ENOMEM;
2941       }
2942     } else if (match_option(option, "--patch-module=", &tail)) {
2943       // --patch-module=<module>=<file>(<pathsep><file>)*
2944       int res = process_patch_mod_option(tail, patch_mod_javabase);
2945       if (res != JNI_OK) {
2946         return res;
2947       }
2948     } else if (match_option(option, "--illegal-access=", &tail)) {
2949       if (!create_property("jdk.module.illegalAccess", tail, ExternalProperty)) {
2950         return JNI_ENOMEM;
2951       }
2952     // -agentlib and -agentpath
2953     } else if (match_option(option, "-agentlib:", &tail) ||
2954           (is_absolute_path = match_option(option, "-agentpath:", &tail))) {
2955       if(tail != NULL) {
2956         const char* pos = strchr(tail, '=');
2957         size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
2958         char* name = strncpy(NEW_C_HEAP_ARRAY(char, len + 1, mtArguments), tail, len);
2959         name[len] = '\0';
2960 
2961         char *options = NULL;
2962         if(pos != NULL) {
2963           options = os::strdup_check_oom(pos + 1, mtArguments);
2964         }
2965 #if !INCLUDE_JVMTI
2966         if (valid_jdwp_agent(name, is_absolute_path)) {
2967           jio_fprintf(defaultStream::error_stream(),
2968             "Debugging agents are not supported in this VM\n");
2969           return JNI_ERR;
2970         }
2971 #endif // !INCLUDE_JVMTI
2972         add_init_agent(name, options, is_absolute_path);
2973       }
2974     // -javaagent
2975     } else if (match_option(option, "-javaagent:", &tail)) {
2976 #if !INCLUDE_JVMTI
2977       jio_fprintf(defaultStream::error_stream(),
2978         "Instrumentation agents are not supported in this VM\n");
2979       return JNI_ERR;
2980 #else
2981       if (tail != NULL) {
2982         size_t length = strlen(tail) + 1;
2983         char *options = NEW_C_HEAP_ARRAY(char, length, mtArguments);
2984         jio_snprintf(options, length, "%s", tail);
2985         add_init_agent("instrument", options, false);
2986         // java agents need module java.instrument
2987         if (!create_numbered_property("jdk.module.addmods", "java.instrument", addmods_count++)) {
2988           return JNI_ENOMEM;
2989         }
2990       }
2991 #endif // !INCLUDE_JVMTI
2992     // -Xnoclassgc
2993     } else if (match_option(option, "-Xnoclassgc")) {
2994       if (FLAG_SET_CMDLINE(bool, ClassUnloading, false) != Flag::SUCCESS) {
2995         return JNI_EINVAL;
2996       }
2997     // -Xconcgc
2998     } else if (match_option(option, "-Xconcgc")) {
2999       if (FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, true) != Flag::SUCCESS) {
3000         return JNI_EINVAL;
3001       }
3002       handle_extra_cms_flags("-Xconcgc uses UseConcMarkSweepGC");
3003     // -Xnoconcgc
3004     } else if (match_option(option, "-Xnoconcgc")) {
3005       if (FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, false) != Flag::SUCCESS) {
3006         return JNI_EINVAL;
3007       }
3008       handle_extra_cms_flags("-Xnoconcgc uses UseConcMarkSweepGC");
3009     // -Xbatch
3010     } else if (match_option(option, "-Xbatch")) {
3011       if (FLAG_SET_CMDLINE(bool, BackgroundCompilation, false) != Flag::SUCCESS) {
3012         return JNI_EINVAL;
3013       }
3014     // -Xmn for compatibility with other JVM vendors
3015     } else if (match_option(option, "-Xmn", &tail)) {
3016       julong long_initial_young_size = 0;
3017       ArgsRange errcode = parse_memory_size(tail, &long_initial_young_size, 1);
3018       if (errcode != arg_in_range) {
3019         jio_fprintf(defaultStream::error_stream(),
3020                     "Invalid initial young generation size: %s\n", option->optionString);
3021         describe_range_error(errcode);
3022         return JNI_EINVAL;
3023       }
3024       if (FLAG_SET_CMDLINE(size_t, MaxNewSize, (size_t)long_initial_young_size) != Flag::SUCCESS) {
3025         return JNI_EINVAL;
3026       }
3027       if (FLAG_SET_CMDLINE(size_t, NewSize, (size_t)long_initial_young_size) != Flag::SUCCESS) {
3028         return JNI_EINVAL;
3029       }
3030     // -Xms
3031     } else if (match_option(option, "-Xms", &tail)) {
3032       julong long_initial_heap_size = 0;
3033       // an initial heap size of 0 means automatically determine
3034       ArgsRange errcode = parse_memory_size(tail, &long_initial_heap_size, 0);
3035       if (errcode != arg_in_range) {
3036         jio_fprintf(defaultStream::error_stream(),
3037                     "Invalid initial heap size: %s\n", option->optionString);
3038         describe_range_error(errcode);
3039         return JNI_EINVAL;
3040       }
3041       set_min_heap_size((size_t)long_initial_heap_size);
3042       // Currently the minimum size and the initial heap sizes are the same.
3043       // Can be overridden with -XX:InitialHeapSize.
3044       if (FLAG_SET_CMDLINE(size_t, InitialHeapSize, (size_t)long_initial_heap_size) != Flag::SUCCESS) {
3045         return JNI_EINVAL;
3046       }
3047     // -Xmx
3048     } else if (match_option(option, "-Xmx", &tail) || match_option(option, "-XX:MaxHeapSize=", &tail)) {
3049       julong long_max_heap_size = 0;
3050       ArgsRange errcode = parse_memory_size(tail, &long_max_heap_size, 1);
3051       if (errcode != arg_in_range) {
3052         jio_fprintf(defaultStream::error_stream(),
3053                     "Invalid maximum heap size: %s\n", option->optionString);
3054         describe_range_error(errcode);
3055         return JNI_EINVAL;
3056       }
3057       if (FLAG_SET_CMDLINE(size_t, MaxHeapSize, (size_t)long_max_heap_size) != Flag::SUCCESS) {
3058         return JNI_EINVAL;
3059       }
3060     // Xmaxf
3061     } else if (match_option(option, "-Xmaxf", &tail)) {
3062       char* err;
3063       int maxf = (int)(strtod(tail, &err) * 100);
3064       if (*err != '\0' || *tail == '\0') {
3065         jio_fprintf(defaultStream::error_stream(),
3066                     "Bad max heap free percentage size: %s\n",
3067                     option->optionString);
3068         return JNI_EINVAL;
3069       } else {
3070         if (FLAG_SET_CMDLINE(uintx, MaxHeapFreeRatio, maxf) != Flag::SUCCESS) {
3071             return JNI_EINVAL;
3072         }
3073       }
3074     // Xminf
3075     } else if (match_option(option, "-Xminf", &tail)) {
3076       char* err;
3077       int minf = (int)(strtod(tail, &err) * 100);
3078       if (*err != '\0' || *tail == '\0') {
3079         jio_fprintf(defaultStream::error_stream(),
3080                     "Bad min heap free percentage size: %s\n",
3081                     option->optionString);
3082         return JNI_EINVAL;
3083       } else {
3084         if (FLAG_SET_CMDLINE(uintx, MinHeapFreeRatio, minf) != Flag::SUCCESS) {
3085           return JNI_EINVAL;
3086         }
3087       }
3088     // -Xss
3089     } else if (match_option(option, "-Xss", &tail)) {
3090       intx value = 0;
3091       jint err = parse_xss(option, tail, &value);
3092       if (err != JNI_OK) {
3093         return err;
3094       }
3095       if (FLAG_SET_CMDLINE(intx, ThreadStackSize, value) != Flag::SUCCESS) {
3096         return JNI_EINVAL;
3097       }
3098     } else if (match_option(option, "-XX:CodeCacheExpansionSize=", &tail)) {
3099       julong long_CodeCacheExpansionSize = 0;
3100       ArgsRange errcode = parse_memory_size(tail, &long_CodeCacheExpansionSize, os::vm_page_size());
3101       if (errcode != arg_in_range) {
3102         jio_fprintf(defaultStream::error_stream(),
3103                    "Invalid argument: %s. Must be at least %luK.\n", option->optionString,
3104                    os::vm_page_size()/K);
3105         return JNI_EINVAL;
3106       }
3107       if (FLAG_SET_CMDLINE(uintx, CodeCacheExpansionSize, (uintx)long_CodeCacheExpansionSize) != Flag::SUCCESS) {
3108         return JNI_EINVAL;
3109       }
3110     } else if (match_option(option, "-Xmaxjitcodesize", &tail) ||
3111                match_option(option, "-XX:ReservedCodeCacheSize=", &tail)) {
3112       julong long_ReservedCodeCacheSize = 0;
3113 
3114       ArgsRange errcode = parse_memory_size(tail, &long_ReservedCodeCacheSize, 1);
3115       if (errcode != arg_in_range) {
3116         jio_fprintf(defaultStream::error_stream(),
3117                     "Invalid maximum code cache size: %s.\n", option->optionString);
3118         return JNI_EINVAL;
3119       }
3120       if (FLAG_SET_CMDLINE(uintx, ReservedCodeCacheSize, (uintx)long_ReservedCodeCacheSize) != Flag::SUCCESS) {
3121         return JNI_EINVAL;
3122       }
3123       // -XX:NonNMethodCodeHeapSize=
3124     } else if (match_option(option, "-XX:NonNMethodCodeHeapSize=", &tail)) {
3125       julong long_NonNMethodCodeHeapSize = 0;
3126 
3127       ArgsRange errcode = parse_memory_size(tail, &long_NonNMethodCodeHeapSize, 1);
3128       if (errcode != arg_in_range) {
3129         jio_fprintf(defaultStream::error_stream(),
3130                     "Invalid maximum non-nmethod code heap size: %s.\n", option->optionString);
3131         return JNI_EINVAL;
3132       }
3133       if (FLAG_SET_CMDLINE(uintx, NonNMethodCodeHeapSize, (uintx)long_NonNMethodCodeHeapSize) != Flag::SUCCESS) {
3134         return JNI_EINVAL;
3135       }
3136       // -XX:ProfiledCodeHeapSize=
3137     } else if (match_option(option, "-XX:ProfiledCodeHeapSize=", &tail)) {
3138       julong long_ProfiledCodeHeapSize = 0;
3139 
3140       ArgsRange errcode = parse_memory_size(tail, &long_ProfiledCodeHeapSize, 1);
3141       if (errcode != arg_in_range) {
3142         jio_fprintf(defaultStream::error_stream(),
3143                     "Invalid maximum profiled code heap size: %s.\n", option->optionString);
3144         return JNI_EINVAL;
3145       }
3146       if (FLAG_SET_CMDLINE(uintx, ProfiledCodeHeapSize, (uintx)long_ProfiledCodeHeapSize) != Flag::SUCCESS) {
3147         return JNI_EINVAL;
3148       }
3149       // -XX:NonProfiledCodeHeapSizee=
3150     } else if (match_option(option, "-XX:NonProfiledCodeHeapSize=", &tail)) {
3151       julong long_NonProfiledCodeHeapSize = 0;
3152 
3153       ArgsRange errcode = parse_memory_size(tail, &long_NonProfiledCodeHeapSize, 1);
3154       if (errcode != arg_in_range) {
3155         jio_fprintf(defaultStream::error_stream(),
3156                     "Invalid maximum non-profiled code heap size: %s.\n", option->optionString);
3157         return JNI_EINVAL;
3158       }
3159       if (FLAG_SET_CMDLINE(uintx, NonProfiledCodeHeapSize, (uintx)long_NonProfiledCodeHeapSize) != Flag::SUCCESS) {
3160         return JNI_EINVAL;
3161       }
3162     // -green
3163     } else if (match_option(option, "-green")) {
3164       jio_fprintf(defaultStream::error_stream(),
3165                   "Green threads support not available\n");
3166           return JNI_EINVAL;
3167     // -native
3168     } else if (match_option(option, "-native")) {
3169           // HotSpot always uses native threads, ignore silently for compatibility
3170     // -Xrs
3171     } else if (match_option(option, "-Xrs")) {
3172           // Classic/EVM option, new functionality
3173       if (FLAG_SET_CMDLINE(bool, ReduceSignalUsage, true) != Flag::SUCCESS) {
3174         return JNI_EINVAL;
3175       }
3176       // -Xprof
3177     } else if (match_option(option, "-Xprof")) {
3178       char version[256];
3179       // Obsolete in JDK 10
3180       JDK_Version::jdk(10).to_string(version, sizeof(version));
3181       warning("Ignoring option %s; support was removed in %s", option->optionString, version);
3182     // -Xconcurrentio
3183     } else if (match_option(option, "-Xconcurrentio")) {
3184       if (FLAG_SET_CMDLINE(bool, UseLWPSynchronization, true) != Flag::SUCCESS) {
3185         return JNI_EINVAL;
3186       }
3187       if (FLAG_SET_CMDLINE(bool, BackgroundCompilation, false) != Flag::SUCCESS) {
3188         return JNI_EINVAL;
3189       }
3190       if (FLAG_SET_CMDLINE(intx, DeferThrSuspendLoopCount, 1) != Flag::SUCCESS) {
3191         return JNI_EINVAL;
3192       }
3193       if (FLAG_SET_CMDLINE(bool, UseTLAB, false) != Flag::SUCCESS) {
3194         return JNI_EINVAL;
3195       }
3196       if (FLAG_SET_CMDLINE(size_t, NewSizeThreadIncrease, 16 * K) != Flag::SUCCESS) {  // 20Kb per thread added to new generation
3197         return JNI_EINVAL;
3198       }
3199 
3200       // -Xinternalversion
3201     } else if (match_option(option, "-Xinternalversion")) {
3202       jio_fprintf(defaultStream::output_stream(), "%s\n",
3203                   VM_Version::internal_vm_info_string());
3204       vm_exit(0);
3205 #ifndef PRODUCT
3206     // -Xprintflags
3207     } else if (match_option(option, "-Xprintflags")) {
3208       CommandLineFlags::printFlags(tty, false);
3209       vm_exit(0);
3210 #endif
3211     // -D
3212     } else if (match_option(option, "-D", &tail)) {
3213       const char* value;
3214       if (match_option(option, "-Djava.endorsed.dirs=", &value) &&
3215             *value!= '\0' && strcmp(value, "\"\"") != 0) {
3216         // abort if -Djava.endorsed.dirs is set
3217         jio_fprintf(defaultStream::output_stream(),
3218           "-Djava.endorsed.dirs=%s is not supported. Endorsed standards and standalone APIs\n"
3219           "in modular form will be supported via the concept of upgradeable modules.\n", value);
3220         return JNI_EINVAL;
3221       }
3222       if (match_option(option, "-Djava.ext.dirs=", &value) &&
3223             *value != '\0' && strcmp(value, "\"\"") != 0) {
3224         // abort if -Djava.ext.dirs is set
3225         jio_fprintf(defaultStream::output_stream(),
3226           "-Djava.ext.dirs=%s is not supported.  Use -classpath instead.\n", value);
3227         return JNI_EINVAL;
3228       }
3229       // Check for module related properties.  They must be set using the modules
3230       // options. For example: use "--add-modules=java.sql", not
3231       // "-Djdk.module.addmods=java.sql"
3232       if (is_internal_module_property(option->optionString + 2)) {
3233         needs_module_property_warning = true;
3234         continue;
3235       }
3236 
3237       if (!add_property(tail)) {
3238         return JNI_ENOMEM;
3239       }
3240       // Out of the box management support
3241       if (match_option(option, "-Dcom.sun.management", &tail)) {
3242 #if INCLUDE_MANAGEMENT
3243         if (FLAG_SET_CMDLINE(bool, ManagementServer, true) != Flag::SUCCESS) {
3244           return JNI_EINVAL;
3245         }
3246         // management agent in module jdk.management.agent
3247         if (!create_numbered_property("jdk.module.addmods", "jdk.management.agent", addmods_count++)) {
3248           return JNI_ENOMEM;
3249         }
3250 #else
3251         jio_fprintf(defaultStream::output_stream(),
3252           "-Dcom.sun.management is not supported in this VM.\n");
3253         return JNI_ERR;
3254 #endif
3255       }
3256     // -Xint
3257     } else if (match_option(option, "-Xint")) {
3258           set_mode_flags(_int);
3259     // -Xmixed
3260     } else if (match_option(option, "-Xmixed")) {
3261           set_mode_flags(_mixed);
3262     // -Xcomp
3263     } else if (match_option(option, "-Xcomp")) {
3264       // for testing the compiler; turn off all flags that inhibit compilation
3265           set_mode_flags(_comp);
3266     // -Xshare:dump
3267     } else if (match_option(option, "-Xshare:dump")) {
3268       if (FLAG_SET_CMDLINE(bool, DumpSharedSpaces, true) != Flag::SUCCESS) {
3269         return JNI_EINVAL;
3270       }
3271       set_mode_flags(_int);     // Prevent compilation, which creates objects
3272     // -Xshare:on
3273     } else if (match_option(option, "-Xshare:on")) {
3274       if (FLAG_SET_CMDLINE(bool, UseSharedSpaces, true) != Flag::SUCCESS) {
3275         return JNI_EINVAL;
3276       }
3277       if (FLAG_SET_CMDLINE(bool, RequireSharedSpaces, true) != Flag::SUCCESS) {
3278         return JNI_EINVAL;
3279       }
3280     // -Xshare:auto
3281     } else if (match_option(option, "-Xshare:auto")) {
3282       if (FLAG_SET_CMDLINE(bool, UseSharedSpaces, true) != Flag::SUCCESS) {
3283         return JNI_EINVAL;
3284       }
3285       if (FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false) != Flag::SUCCESS) {
3286         return JNI_EINVAL;
3287       }
3288     // -Xshare:off
3289     } else if (match_option(option, "-Xshare:off")) {
3290       if (FLAG_SET_CMDLINE(bool, UseSharedSpaces, false) != Flag::SUCCESS) {
3291         return JNI_EINVAL;
3292       }
3293       if (FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false) != Flag::SUCCESS) {
3294         return JNI_EINVAL;
3295       }
3296     // -Xverify
3297     } else if (match_option(option, "-Xverify", &tail)) {
3298       if (strcmp(tail, ":all") == 0 || strcmp(tail, "") == 0) {
3299         if (FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, true) != Flag::SUCCESS) {
3300           return JNI_EINVAL;
3301         }
3302         if (FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true) != Flag::SUCCESS) {
3303           return JNI_EINVAL;
3304         }
3305       } else if (strcmp(tail, ":remote") == 0) {
3306         if (FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false) != Flag::SUCCESS) {
3307           return JNI_EINVAL;
3308         }
3309         if (FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true) != Flag::SUCCESS) {
3310           return JNI_EINVAL;
3311         }
3312       } else if (strcmp(tail, ":none") == 0) {
3313         if (FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false) != Flag::SUCCESS) {
3314           return JNI_EINVAL;
3315         }
3316         if (FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, false) != Flag::SUCCESS) {
3317           return JNI_EINVAL;
3318         }
3319       } else if (is_bad_option(option, args->ignoreUnrecognized, "verification")) {
3320         return JNI_EINVAL;
3321       }
3322     // -Xdebug
3323     } else if (match_option(option, "-Xdebug")) {
3324       // note this flag has been used, then ignore
3325       set_xdebug_mode(true);
3326     // -Xnoagent
3327     } else if (match_option(option, "-Xnoagent")) {
3328       // For compatibility with classic. HotSpot refuses to load the old style agent.dll.
3329     } else if (match_option(option, "-Xloggc:", &tail)) {
3330       // Deprecated flag to redirect GC output to a file. -Xloggc:<filename>
3331       log_warning(gc)("-Xloggc is deprecated. Will use -Xlog:gc:%s instead.", tail);
3332       _gc_log_filename = os::strdup_check_oom(tail);
3333     } else if (match_option(option, "-Xlog", &tail)) {
3334       bool ret = false;
3335       if (strcmp(tail, ":help") == 0) {
3336         LogConfiguration::print_command_line_help(defaultStream::output_stream());
3337         vm_exit(0);
3338       } else if (strcmp(tail, ":disable") == 0) {
3339         LogConfiguration::disable_logging();
3340         ret = true;
3341       } else if (*tail == '\0') {
3342         ret = LogConfiguration::parse_command_line_arguments();
3343         assert(ret, "-Xlog without arguments should never fail to parse");
3344       } else if (*tail == ':') {
3345         ret = LogConfiguration::parse_command_line_arguments(tail + 1);
3346       }
3347       if (ret == false) {
3348         jio_fprintf(defaultStream::error_stream(),
3349                     "Invalid -Xlog option '-Xlog%s'\n",
3350                     tail);
3351         return JNI_EINVAL;
3352       }
3353     // JNI hooks
3354     } else if (match_option(option, "-Xcheck", &tail)) {
3355       if (!strcmp(tail, ":jni")) {
3356 #if !INCLUDE_JNI_CHECK
3357         warning("JNI CHECKING is not supported in this VM");
3358 #else
3359         CheckJNICalls = true;
3360 #endif // INCLUDE_JNI_CHECK
3361       } else if (is_bad_option(option, args->ignoreUnrecognized,
3362                                      "check")) {
3363         return JNI_EINVAL;
3364       }
3365     } else if (match_option(option, "vfprintf")) {
3366       _vfprintf_hook = CAST_TO_FN_PTR(vfprintf_hook_t, option->extraInfo);
3367     } else if (match_option(option, "exit")) {
3368       _exit_hook = CAST_TO_FN_PTR(exit_hook_t, option->extraInfo);
3369     } else if (match_option(option, "abort")) {
3370       _abort_hook = CAST_TO_FN_PTR(abort_hook_t, option->extraInfo);
3371     // -XX:+AggressiveHeap
3372     } else if (match_option(option, "-XX:+AggressiveHeap")) {
3373       jint result = set_aggressive_heap_flags();
3374       if (result != JNI_OK) {
3375           return result;
3376       }
3377     // Need to keep consistency of MaxTenuringThreshold and AlwaysTenure/NeverTenure;
3378     // and the last option wins.
3379     } else if (match_option(option, "-XX:+NeverTenure")) {
3380       if (FLAG_SET_CMDLINE(bool, NeverTenure, true) != Flag::SUCCESS) {
3381         return JNI_EINVAL;
3382       }
3383       if (FLAG_SET_CMDLINE(bool, AlwaysTenure, false) != Flag::SUCCESS) {
3384         return JNI_EINVAL;
3385       }
3386       if (FLAG_SET_CMDLINE(uintx, MaxTenuringThreshold, markOopDesc::max_age + 1) != Flag::SUCCESS) {
3387         return JNI_EINVAL;
3388       }
3389     } else if (match_option(option, "-XX:+AlwaysTenure")) {
3390       if (FLAG_SET_CMDLINE(bool, NeverTenure, false) != Flag::SUCCESS) {
3391         return JNI_EINVAL;
3392       }
3393       if (FLAG_SET_CMDLINE(bool, AlwaysTenure, true) != Flag::SUCCESS) {
3394         return JNI_EINVAL;
3395       }
3396       if (FLAG_SET_CMDLINE(uintx, MaxTenuringThreshold, 0) != Flag::SUCCESS) {
3397         return JNI_EINVAL;
3398       }
3399     } else if (match_option(option, "-XX:MaxTenuringThreshold=", &tail)) {
3400       uintx max_tenuring_thresh = 0;
3401       if (!parse_uintx(tail, &max_tenuring_thresh, 0)) {
3402         jio_fprintf(defaultStream::error_stream(),
3403                     "Improperly specified VM option \'MaxTenuringThreshold=%s\'\n", tail);
3404         return JNI_EINVAL;
3405       }
3406 
3407       if (FLAG_SET_CMDLINE(uintx, MaxTenuringThreshold, max_tenuring_thresh) != Flag::SUCCESS) {
3408         return JNI_EINVAL;
3409       }
3410 
3411       if (MaxTenuringThreshold == 0) {
3412         if (FLAG_SET_CMDLINE(bool, NeverTenure, false) != Flag::SUCCESS) {
3413           return JNI_EINVAL;
3414         }
3415         if (FLAG_SET_CMDLINE(bool, AlwaysTenure, true) != Flag::SUCCESS) {
3416           return JNI_EINVAL;
3417         }
3418       } else {
3419         if (FLAG_SET_CMDLINE(bool, NeverTenure, false) != Flag::SUCCESS) {
3420           return JNI_EINVAL;
3421         }
3422         if (FLAG_SET_CMDLINE(bool, AlwaysTenure, false) != Flag::SUCCESS) {
3423           return JNI_EINVAL;
3424         }
3425       }
3426     } else if (match_option(option, "-XX:+DisplayVMOutputToStderr")) {
3427       if (FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, false) != Flag::SUCCESS) {
3428         return JNI_EINVAL;
3429       }
3430       if (FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, true) != Flag::SUCCESS) {
3431         return JNI_EINVAL;
3432       }
3433     } else if (match_option(option, "-XX:+DisplayVMOutputToStdout")) {
3434       if (FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, false) != Flag::SUCCESS) {
3435         return JNI_EINVAL;
3436       }
3437       if (FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, true) != Flag::SUCCESS) {
3438         return JNI_EINVAL;
3439       }
3440     } else if (match_option(option, "-XX:+ExtendedDTraceProbes")) {
3441 #if defined(DTRACE_ENABLED)
3442       if (FLAG_SET_CMDLINE(bool, ExtendedDTraceProbes, true) != Flag::SUCCESS) {
3443         return JNI_EINVAL;
3444       }
3445       if (FLAG_SET_CMDLINE(bool, DTraceMethodProbes, true) != Flag::SUCCESS) {
3446         return JNI_EINVAL;
3447       }
3448       if (FLAG_SET_CMDLINE(bool, DTraceAllocProbes, true) != Flag::SUCCESS) {
3449         return JNI_EINVAL;
3450       }
3451       if (FLAG_SET_CMDLINE(bool, DTraceMonitorProbes, true) != Flag::SUCCESS) {
3452         return JNI_EINVAL;
3453       }
3454 #else // defined(DTRACE_ENABLED)
3455       jio_fprintf(defaultStream::error_stream(),
3456                   "ExtendedDTraceProbes flag is not applicable for this configuration\n");
3457       return JNI_EINVAL;
3458 #endif // defined(DTRACE_ENABLED)
3459 #ifdef ASSERT
3460     } else if (match_option(option, "-XX:+FullGCALot")) {
3461       if (FLAG_SET_CMDLINE(bool, FullGCALot, true) != Flag::SUCCESS) {
3462         return JNI_EINVAL;
3463       }
3464       // disable scavenge before parallel mark-compact
3465       if (FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false) != Flag::SUCCESS) {
3466         return JNI_EINVAL;
3467       }
3468 #endif
3469 #if !INCLUDE_MANAGEMENT
3470     } else if (match_option(option, "-XX:+ManagementServer")) {
3471         jio_fprintf(defaultStream::error_stream(),
3472           "ManagementServer is not supported in this VM.\n");
3473         return JNI_ERR;
3474 #endif // INCLUDE_MANAGEMENT
3475     } else if (match_option(option, "-XX:", &tail)) { // -XX:xxxx
3476       // Skip -XX:Flags= and -XX:VMOptionsFile= since those cases have
3477       // already been handled
3478       if ((strncmp(tail, "Flags=", strlen("Flags=")) != 0) &&
3479           (strncmp(tail, "VMOptionsFile=", strlen("VMOptionsFile=")) != 0)) {
3480         if (!process_argument(tail, args->ignoreUnrecognized, origin)) {
3481           return JNI_EINVAL;
3482         }
3483       }
3484     // Unknown option
3485     } else if (is_bad_option(option, args->ignoreUnrecognized)) {
3486       return JNI_ERR;
3487     }
3488   }
3489 
3490   // PrintSharedArchiveAndExit will turn on
3491   //   -Xshare:on
3492   //   -Xlog:class+path=info
3493   if (PrintSharedArchiveAndExit) {
3494     if (FLAG_SET_CMDLINE(bool, UseSharedSpaces, true) != Flag::SUCCESS) {
3495       return JNI_EINVAL;
3496     }
3497     if (FLAG_SET_CMDLINE(bool, RequireSharedSpaces, true) != Flag::SUCCESS) {
3498       return JNI_EINVAL;
3499     }
3500     LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(class, path));
3501   }
3502 
3503   // Change the default value for flags  which have different default values
3504   // when working with older JDKs.
3505 #ifdef LINUX
3506  if (JDK_Version::current().compare_major(6) <= 0 &&
3507       FLAG_IS_DEFAULT(UseLinuxPosixThreadCPUClocks)) {
3508     FLAG_SET_DEFAULT(UseLinuxPosixThreadCPUClocks, false);
3509   }
3510 #endif // LINUX
3511   fix_appclasspath();
3512   return JNI_OK;
3513 }
3514 
3515 void Arguments::add_patch_mod_prefix(const char* module_name, const char* path, bool* patch_mod_javabase) {
3516   // For java.base check for duplicate --patch-module options being specified on the command line.
3517   // This check is only required for java.base, all other duplicate module specifications
3518   // will be checked during module system initialization.  The module system initialization
3519   // will throw an ExceptionInInitializerError if this situation occurs.
3520   if (strcmp(module_name, JAVA_BASE_NAME) == 0) {
3521     if (*patch_mod_javabase) {
3522       vm_exit_during_initialization("Cannot specify " JAVA_BASE_NAME " more than once to --patch-module");
3523     } else {
3524       *patch_mod_javabase = true;
3525     }
3526   }
3527 
3528   // Create GrowableArray lazily, only if --patch-module has been specified
3529   if (_patch_mod_prefix == NULL) {
3530     _patch_mod_prefix = new (ResourceObj::C_HEAP, mtArguments) GrowableArray<ModulePatchPath*>(10, true);
3531   }
3532 
3533   _patch_mod_prefix->push(new ModulePatchPath(module_name, path));
3534 }
3535 
3536 // Remove all empty paths from the app classpath (if IgnoreEmptyClassPaths is enabled)
3537 //
3538 // This is necessary because some apps like to specify classpath like -cp foo.jar:${XYZ}:bar.jar
3539 // in their start-up scripts. If XYZ is empty, the classpath will look like "-cp foo.jar::bar.jar".
3540 // Java treats such empty paths as if the user specified "-cp foo.jar:.:bar.jar". I.e., an empty
3541 // path is treated as the current directory.
3542 //
3543 // This causes problems with CDS, which requires that all directories specified in the classpath
3544 // must be empty. In most cases, applications do NOT want to load classes from the current
3545 // directory anyway. Adding -XX:+IgnoreEmptyClassPaths will make these applications' start-up
3546 // scripts compatible with CDS.
3547 void Arguments::fix_appclasspath() {
3548   if (IgnoreEmptyClassPaths) {
3549     const char separator = *os::path_separator();
3550     const char* src = _java_class_path->value();
3551 
3552     // skip over all the leading empty paths
3553     while (*src == separator) {
3554       src ++;
3555     }
3556 
3557     char* copy = os::strdup_check_oom(src, mtArguments);
3558 
3559     // trim all trailing empty paths
3560     for (char* tail = copy + strlen(copy) - 1; tail >= copy && *tail == separator; tail--) {
3561       *tail = '\0';
3562     }
3563 
3564     char from[3] = {separator, separator, '\0'};
3565     char to  [2] = {separator, '\0'};
3566     while (StringUtils::replace_no_expand(copy, from, to) > 0) {
3567       // Keep replacing "::" -> ":" until we have no more "::" (non-windows)
3568       // Keep replacing ";;" -> ";" until we have no more ";;" (windows)
3569     }
3570 
3571     _java_class_path->set_writeable_value(copy);
3572     FreeHeap(copy); // a copy was made by set_value, so don't need this anymore
3573   }
3574 }
3575 
3576 static bool has_jar_files(const char* directory) {
3577   DIR* dir = os::opendir(directory);
3578   if (dir == NULL) return false;
3579 
3580   struct dirent *entry;
3581   char *dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory), mtArguments);
3582   bool hasJarFile = false;
3583   while (!hasJarFile && (entry = os::readdir(dir, (dirent *) dbuf)) != NULL) {
3584     const char* name = entry->d_name;
3585     const char* ext = name + strlen(name) - 4;
3586     hasJarFile = ext > name && (os::file_name_strcmp(ext, ".jar") == 0);
3587   }
3588   FREE_C_HEAP_ARRAY(char, dbuf);
3589   os::closedir(dir);
3590   return hasJarFile ;
3591 }
3592 
3593 static int check_non_empty_dirs(const char* path) {
3594   const char separator = *os::path_separator();
3595   const char* const end = path + strlen(path);
3596   int nonEmptyDirs = 0;
3597   while (path < end) {
3598     const char* tmp_end = strchr(path, separator);
3599     if (tmp_end == NULL) {
3600       if (has_jar_files(path)) {
3601         nonEmptyDirs++;
3602         jio_fprintf(defaultStream::output_stream(),
3603           "Non-empty directory: %s\n", path);
3604       }
3605       path = end;
3606     } else {
3607       char* dirpath = NEW_C_HEAP_ARRAY(char, tmp_end - path + 1, mtArguments);
3608       memcpy(dirpath, path, tmp_end - path);
3609       dirpath[tmp_end - path] = '\0';
3610       if (has_jar_files(dirpath)) {
3611         nonEmptyDirs++;
3612         jio_fprintf(defaultStream::output_stream(),
3613           "Non-empty directory: %s\n", dirpath);
3614       }
3615       FREE_C_HEAP_ARRAY(char, dirpath);
3616       path = tmp_end + 1;
3617     }
3618   }
3619   return nonEmptyDirs;
3620 }
3621 
3622 jint Arguments::finalize_vm_init_args(bool patch_mod_javabase) {
3623   // check if the default lib/endorsed directory exists; if so, error
3624   char path[JVM_MAXPATHLEN];
3625   const char* fileSep = os::file_separator();
3626   jio_snprintf(path, JVM_MAXPATHLEN, "%s%slib%sendorsed", Arguments::get_java_home(), fileSep, fileSep);
3627 
3628   if (CheckEndorsedAndExtDirs) {
3629     int nonEmptyDirs = 0;
3630     // check endorsed directory
3631     nonEmptyDirs += check_non_empty_dirs(path);
3632     // check the extension directories
3633     nonEmptyDirs += check_non_empty_dirs(Arguments::get_ext_dirs());
3634     if (nonEmptyDirs > 0) {
3635       return JNI_ERR;
3636     }
3637   }
3638 
3639   DIR* dir = os::opendir(path);
3640   if (dir != NULL) {
3641     jio_fprintf(defaultStream::output_stream(),
3642       "<JAVA_HOME>/lib/endorsed is not supported. Endorsed standards and standalone APIs\n"
3643       "in modular form will be supported via the concept of upgradeable modules.\n");
3644     os::closedir(dir);
3645     return JNI_ERR;
3646   }
3647 
3648   jio_snprintf(path, JVM_MAXPATHLEN, "%s%slib%sext", Arguments::get_java_home(), fileSep, fileSep);
3649   dir = os::opendir(path);
3650   if (dir != NULL) {
3651     jio_fprintf(defaultStream::output_stream(),
3652       "<JAVA_HOME>/lib/ext exists, extensions mechanism no longer supported; "
3653       "Use -classpath instead.\n.");
3654     os::closedir(dir);
3655     return JNI_ERR;
3656   }
3657 
3658   // This must be done after all arguments have been processed.
3659   // java_compiler() true means set to "NONE" or empty.
3660   if (java_compiler() && !xdebug_mode()) {
3661     // For backwards compatibility, we switch to interpreted mode if
3662     // -Djava.compiler="NONE" or "" is specified AND "-Xdebug" was
3663     // not specified.
3664     set_mode_flags(_int);
3665   }
3666 
3667   // CompileThresholdScaling == 0.0 is same as -Xint: Disable compilation (enable interpreter-only mode),
3668   // but like -Xint, leave compilation thresholds unaffected.
3669   // With tiered compilation disabled, setting CompileThreshold to 0 disables compilation as well.
3670   if ((CompileThresholdScaling == 0.0) || (!TieredCompilation && CompileThreshold == 0)) {
3671     set_mode_flags(_int);
3672   }
3673 
3674   // eventually fix up InitialTenuringThreshold if only MaxTenuringThreshold is set
3675   if (FLAG_IS_DEFAULT(InitialTenuringThreshold) && (InitialTenuringThreshold > MaxTenuringThreshold)) {
3676     FLAG_SET_ERGO(uintx, InitialTenuringThreshold, MaxTenuringThreshold);
3677   }
3678 
3679 #if !defined(COMPILER2) && !INCLUDE_JVMCI
3680   // Don't degrade server performance for footprint
3681   if (FLAG_IS_DEFAULT(UseLargePages) &&
3682       MaxHeapSize < LargePageHeapSizeThreshold) {
3683     // No need for large granularity pages w/small heaps.
3684     // Note that large pages are enabled/disabled for both the
3685     // Java heap and the code cache.
3686     FLAG_SET_DEFAULT(UseLargePages, false);
3687   }
3688 
3689 #elif defined(COMPILER2)
3690   if (!FLAG_IS_DEFAULT(OptoLoopAlignment) && FLAG_IS_DEFAULT(MaxLoopPad)) {
3691     FLAG_SET_DEFAULT(MaxLoopPad, OptoLoopAlignment-1);
3692   }
3693 #endif
3694 
3695 #if !defined(COMPILER2) && !INCLUDE_JVMCI
3696   UNSUPPORTED_OPTION(ProfileInterpreter);
3697   NOT_PRODUCT(UNSUPPORTED_OPTION(TraceProfileInterpreter));
3698 #endif
3699 
3700 #ifndef TIERED
3701   // Tiered compilation is undefined.
3702   UNSUPPORTED_OPTION(TieredCompilation);
3703 #endif
3704 
3705 #if INCLUDE_JVMCI
3706   if (EnableJVMCI &&
3707       !create_numbered_property("jdk.module.addmods", "jdk.internal.vm.ci", addmods_count++)) {
3708     return JNI_ENOMEM;
3709   }
3710 #endif
3711 
3712   // If we are running in a headless jre, force java.awt.headless property
3713   // to be true unless the property has already been set.
3714   // Also allow the OS environment variable JAVA_AWT_HEADLESS to set headless state.
3715   if (os::is_headless_jre()) {
3716     const char* headless = Arguments::get_property("java.awt.headless");
3717     if (headless == NULL) {
3718       const char *headless_env = ::getenv("JAVA_AWT_HEADLESS");
3719       if (headless_env == NULL) {
3720         if (!add_property("java.awt.headless=true")) {
3721           return JNI_ENOMEM;
3722         }
3723       } else {
3724         char buffer[256];
3725         jio_snprintf(buffer, sizeof(buffer), "java.awt.headless=%s", headless_env);
3726         if (!add_property(buffer)) {
3727           return JNI_ENOMEM;
3728         }
3729       }
3730     }
3731   }
3732 
3733   if (!check_vm_args_consistency()) {
3734     return JNI_ERR;
3735   }
3736 
3737 #if INCLUDE_JVMCI
3738   if (UseJVMCICompiler) {
3739     Compilation_mode = CompMode_server;
3740   }
3741 #endif
3742 
3743 #if INCLUDE_CDS
3744   if (DumpSharedSpaces) {
3745     // Disable biased locking now as it interferes with the clean up of
3746     // the archived Klasses and Java string objects (at dump time only).
3747     UseBiasedLocking = false;
3748   }
3749   if (UseSharedSpaces && patch_mod_javabase) {
3750     no_shared_spaces("CDS is disabled when " JAVA_BASE_NAME " module is patched.");
3751   }
3752 #endif
3753 
3754   return JNI_OK;
3755 }
3756 
3757 // Helper class for controlling the lifetime of JavaVMInitArgs
3758 // objects.  The contents of the JavaVMInitArgs are guaranteed to be
3759 // deleted on the destruction of the ScopedVMInitArgs object.
3760 class ScopedVMInitArgs : public StackObj {
3761  private:
3762   JavaVMInitArgs _args;
3763   char*          _container_name;
3764   bool           _is_set;
3765   char*          _vm_options_file_arg;
3766 
3767  public:
3768   ScopedVMInitArgs(const char *container_name) {
3769     _args.version = JNI_VERSION_1_2;
3770     _args.nOptions = 0;
3771     _args.options = NULL;
3772     _args.ignoreUnrecognized = false;
3773     _container_name = (char *)container_name;
3774     _is_set = false;
3775     _vm_options_file_arg = NULL;
3776   }
3777 
3778   // Populates the JavaVMInitArgs object represented by this
3779   // ScopedVMInitArgs object with the arguments in options.  The
3780   // allocated memory is deleted by the destructor.  If this method
3781   // returns anything other than JNI_OK, then this object is in a
3782   // partially constructed state, and should be abandoned.
3783   jint set_args(GrowableArray<JavaVMOption>* options) {
3784     _is_set = true;
3785     JavaVMOption* options_arr = NEW_C_HEAP_ARRAY_RETURN_NULL(
3786         JavaVMOption, options->length(), mtArguments);
3787     if (options_arr == NULL) {
3788       return JNI_ENOMEM;
3789     }
3790     _args.options = options_arr;
3791 
3792     for (int i = 0; i < options->length(); i++) {
3793       options_arr[i] = options->at(i);
3794       options_arr[i].optionString = os::strdup(options_arr[i].optionString);
3795       if (options_arr[i].optionString == NULL) {
3796         // Rely on the destructor to do cleanup.
3797         _args.nOptions = i;
3798         return JNI_ENOMEM;
3799       }
3800     }
3801 
3802     _args.nOptions = options->length();
3803     _args.ignoreUnrecognized = IgnoreUnrecognizedVMOptions;
3804     return JNI_OK;
3805   }
3806 
3807   JavaVMInitArgs* get()             { return &_args; }
3808   char* container_name()            { return _container_name; }
3809   bool  is_set()                    { return _is_set; }
3810   bool  found_vm_options_file_arg() { return _vm_options_file_arg != NULL; }
3811   char* vm_options_file_arg()       { return _vm_options_file_arg; }
3812 
3813   void set_vm_options_file_arg(const char *vm_options_file_arg) {
3814     if (_vm_options_file_arg != NULL) {
3815       os::free(_vm_options_file_arg);
3816     }
3817     _vm_options_file_arg = os::strdup_check_oom(vm_options_file_arg);
3818   }
3819 
3820   ~ScopedVMInitArgs() {
3821     if (_vm_options_file_arg != NULL) {
3822       os::free(_vm_options_file_arg);
3823     }
3824     if (_args.options == NULL) return;
3825     for (int i = 0; i < _args.nOptions; i++) {
3826       os::free(_args.options[i].optionString);
3827     }
3828     FREE_C_HEAP_ARRAY(JavaVMOption, _args.options);
3829   }
3830 
3831   // Insert options into this option list, to replace option at
3832   // vm_options_file_pos (-XX:VMOptionsFile)
3833   jint insert(const JavaVMInitArgs* args,
3834               const JavaVMInitArgs* args_to_insert,
3835               const int vm_options_file_pos) {
3836     assert(_args.options == NULL, "shouldn't be set yet");
3837     assert(args_to_insert->nOptions != 0, "there should be args to insert");
3838     assert(vm_options_file_pos != -1, "vm_options_file_pos should be set");
3839 
3840     int length = args->nOptions + args_to_insert->nOptions - 1;
3841     GrowableArray<JavaVMOption> *options = new (ResourceObj::C_HEAP, mtArguments)
3842               GrowableArray<JavaVMOption>(length, true);    // Construct new option array
3843     for (int i = 0; i < args->nOptions; i++) {
3844       if (i == vm_options_file_pos) {
3845         // insert the new options starting at the same place as the
3846         // -XX:VMOptionsFile option
3847         for (int j = 0; j < args_to_insert->nOptions; j++) {
3848           options->push(args_to_insert->options[j]);
3849         }
3850       } else {
3851         options->push(args->options[i]);
3852       }
3853     }
3854     // make into options array
3855     jint result = set_args(options);
3856     delete options;
3857     return result;
3858   }
3859 };
3860 
3861 jint Arguments::parse_java_options_environment_variable(ScopedVMInitArgs* args) {
3862   return parse_options_environment_variable("_JAVA_OPTIONS", args);
3863 }
3864 
3865 jint Arguments::parse_java_tool_options_environment_variable(ScopedVMInitArgs* args) {
3866   return parse_options_environment_variable("JAVA_TOOL_OPTIONS", args);
3867 }
3868 
3869 jint Arguments::parse_options_environment_variable(const char* name,
3870                                                    ScopedVMInitArgs* vm_args) {
3871   char *buffer = ::getenv(name);
3872 
3873   // Don't check this environment variable if user has special privileges
3874   // (e.g. unix su command).
3875   if (buffer == NULL || os::have_special_privileges()) {
3876     return JNI_OK;
3877   }
3878 
3879   if ((buffer = os::strdup(buffer)) == NULL) {
3880     return JNI_ENOMEM;
3881   }
3882 
3883   jio_fprintf(defaultStream::error_stream(),
3884               "Picked up %s: %s\n", name, buffer);
3885 
3886   int retcode = parse_options_buffer(name, buffer, strlen(buffer), vm_args);
3887 
3888   os::free(buffer);
3889   return retcode;
3890 }
3891 
3892 jint Arguments::parse_vm_options_file(const char* file_name, ScopedVMInitArgs* vm_args) {
3893   // read file into buffer
3894   int fd = ::open(file_name, O_RDONLY);
3895   if (fd < 0) {
3896     jio_fprintf(defaultStream::error_stream(),
3897                 "Could not open options file '%s'\n",
3898                 file_name);
3899     return JNI_ERR;
3900   }
3901 
3902   struct stat stbuf;
3903   int retcode = os::stat(file_name, &stbuf);
3904   if (retcode != 0) {
3905     jio_fprintf(defaultStream::error_stream(),
3906                 "Could not stat options file '%s'\n",
3907                 file_name);
3908     os::close(fd);
3909     return JNI_ERR;
3910   }
3911 
3912   if (stbuf.st_size == 0) {
3913     // tell caller there is no option data and that is ok
3914     os::close(fd);
3915     return JNI_OK;
3916   }
3917 
3918   // '+ 1' for NULL termination even with max bytes
3919   size_t bytes_alloc = stbuf.st_size + 1;
3920 
3921   char *buf = NEW_C_HEAP_ARRAY_RETURN_NULL(char, bytes_alloc, mtArguments);
3922   if (NULL == buf) {
3923     jio_fprintf(defaultStream::error_stream(),
3924                 "Could not allocate read buffer for options file parse\n");
3925     os::close(fd);
3926     return JNI_ENOMEM;
3927   }
3928 
3929   memset(buf, 0, bytes_alloc);
3930 
3931   // Fill buffer
3932   // Use ::read() instead of os::read because os::read()
3933   // might do a thread state transition
3934   // and it is too early for that here
3935 
3936   ssize_t bytes_read = ::read(fd, (void *)buf, (unsigned)bytes_alloc);
3937   os::close(fd);
3938   if (bytes_read < 0) {
3939     FREE_C_HEAP_ARRAY(char, buf);
3940     jio_fprintf(defaultStream::error_stream(),
3941                 "Could not read options file '%s'\n", file_name);
3942     return JNI_ERR;
3943   }
3944 
3945   if (bytes_read == 0) {
3946     // tell caller there is no option data and that is ok
3947     FREE_C_HEAP_ARRAY(char, buf);
3948     return JNI_OK;
3949   }
3950 
3951   retcode = parse_options_buffer(file_name, buf, bytes_read, vm_args);
3952 
3953   FREE_C_HEAP_ARRAY(char, buf);
3954   return retcode;
3955 }
3956 
3957 jint Arguments::parse_options_buffer(const char* name, char* buffer, const size_t buf_len, ScopedVMInitArgs* vm_args) {
3958   GrowableArray<JavaVMOption> *options = new (ResourceObj::C_HEAP, mtArguments) GrowableArray<JavaVMOption>(2, true);    // Construct option array
3959 
3960   // some pointers to help with parsing
3961   char *buffer_end = buffer + buf_len;
3962   char *opt_hd = buffer;
3963   char *wrt = buffer;
3964   char *rd = buffer;
3965 
3966   // parse all options
3967   while (rd < buffer_end) {
3968     // skip leading white space from the input string
3969     while (rd < buffer_end && isspace(*rd)) {
3970       rd++;
3971     }
3972 
3973     if (rd >= buffer_end) {
3974       break;
3975     }
3976 
3977     // Remember this is where we found the head of the token.
3978     opt_hd = wrt;
3979 
3980     // Tokens are strings of non white space characters separated
3981     // by one or more white spaces.
3982     while (rd < buffer_end && !isspace(*rd)) {
3983       if (*rd == '\'' || *rd == '"') {      // handle a quoted string
3984         int quote = *rd;                    // matching quote to look for
3985         rd++;                               // don't copy open quote
3986         while (rd < buffer_end && *rd != quote) {
3987                                             // include everything (even spaces)
3988                                             // up until the close quote
3989           *wrt++ = *rd++;                   // copy to option string
3990         }
3991 
3992         if (rd < buffer_end) {
3993           rd++;                             // don't copy close quote
3994         } else {
3995                                             // did not see closing quote
3996           jio_fprintf(defaultStream::error_stream(),
3997                       "Unmatched quote in %s\n", name);
3998           delete options;
3999           return JNI_ERR;
4000         }
4001       } else {
4002         *wrt++ = *rd++;                     // copy to option string
4003       }
4004     }
4005 
4006     // steal a white space character and set it to NULL
4007     *wrt++ = '\0';
4008     // We now have a complete token
4009 
4010     JavaVMOption option;
4011     option.optionString = opt_hd;
4012     option.extraInfo = NULL;
4013 
4014     options->append(option);                // Fill in option
4015 
4016     rd++;  // Advance to next character
4017   }
4018 
4019   // Fill out JavaVMInitArgs structure.
4020   jint status = vm_args->set_args(options);
4021 
4022   delete options;
4023   return status;
4024 }
4025 
4026 void Arguments::set_shared_spaces_flags() {
4027   if (DumpSharedSpaces) {
4028     if (FailOverToOldVerifier) {
4029       // Don't fall back to the old verifier on verification failure. If a
4030       // class fails verification with the split verifier, it might fail the
4031       // CDS runtime verifier constraint check. In that case, we don't want
4032       // to share the class. We only archive classes that pass the split verifier.
4033       FLAG_SET_DEFAULT(FailOverToOldVerifier, false);
4034     }
4035 
4036     if (RequireSharedSpaces) {
4037       warning("Cannot dump shared archive while using shared archive");
4038     }
4039     UseSharedSpaces = false;
4040 #ifdef _LP64
4041     if (!UseCompressedOops || !UseCompressedClassPointers) {
4042       vm_exit_during_initialization(
4043         "Cannot dump shared archive when UseCompressedOops or UseCompressedClassPointers is off.", NULL);
4044     }
4045   } else {
4046     if (!UseCompressedOops || !UseCompressedClassPointers) {
4047       no_shared_spaces("UseCompressedOops and UseCompressedClassPointers must be on for UseSharedSpaces.");
4048     }
4049 #endif
4050   }
4051 }
4052 
4053 // Sharing support
4054 // Construct the path to the archive
4055 static char* get_shared_archive_path() {
4056   char *shared_archive_path;
4057   if (SharedArchiveFile == NULL) {
4058     char jvm_path[JVM_MAXPATHLEN];
4059     os::jvm_path(jvm_path, sizeof(jvm_path));
4060     char *end = strrchr(jvm_path, *os::file_separator());
4061     if (end != NULL) *end = '\0';
4062     size_t jvm_path_len = strlen(jvm_path);
4063     size_t file_sep_len = strlen(os::file_separator());
4064     const size_t len = jvm_path_len + file_sep_len + 20;
4065     shared_archive_path = NEW_C_HEAP_ARRAY(char, len, mtArguments);
4066     if (shared_archive_path != NULL) {
4067       jio_snprintf(shared_archive_path, len, "%s%sclasses.jsa",
4068         jvm_path, os::file_separator());
4069     }
4070   } else {
4071     shared_archive_path = os::strdup_check_oom(SharedArchiveFile, mtArguments);
4072   }
4073   return shared_archive_path;
4074 }
4075 
4076 #ifndef PRODUCT
4077 // Determine whether LogVMOutput should be implicitly turned on.
4078 static bool use_vm_log() {
4079   if (LogCompilation || !FLAG_IS_DEFAULT(LogFile) ||
4080       PrintCompilation || PrintInlining || PrintDependencies || PrintNativeNMethods ||
4081       PrintDebugInfo || PrintRelocations || PrintNMethods || PrintExceptionHandlers ||
4082       PrintAssembly || TraceDeoptimization || TraceDependencies ||
4083       (VerifyDependencies && FLAG_IS_CMDLINE(VerifyDependencies))) {
4084     return true;
4085   }
4086 
4087 #ifdef COMPILER1
4088   if (PrintC1Statistics) {
4089     return true;
4090   }
4091 #endif // COMPILER1
4092 
4093 #ifdef COMPILER2
4094   if (PrintOptoAssembly || PrintOptoStatistics) {
4095     return true;
4096   }
4097 #endif // COMPILER2
4098 
4099   return false;
4100 }
4101 
4102 #endif // PRODUCT
4103 
4104 bool Arguments::args_contains_vm_options_file_arg(const JavaVMInitArgs* args) {
4105   for (int index = 0; index < args->nOptions; index++) {
4106     const JavaVMOption* option = args->options + index;
4107     const char* tail;
4108     if (match_option(option, "-XX:VMOptionsFile=", &tail)) {
4109       return true;
4110     }
4111   }
4112   return false;
4113 }
4114 
4115 jint Arguments::insert_vm_options_file(const JavaVMInitArgs* args,
4116                                        const char* vm_options_file,
4117                                        const int vm_options_file_pos,
4118                                        ScopedVMInitArgs* vm_options_file_args,
4119                                        ScopedVMInitArgs* args_out) {
4120   jint code = parse_vm_options_file(vm_options_file, vm_options_file_args);
4121   if (code != JNI_OK) {
4122     return code;
4123   }
4124 
4125   if (vm_options_file_args->get()->nOptions < 1) {
4126     return JNI_OK;
4127   }
4128 
4129   if (args_contains_vm_options_file_arg(vm_options_file_args->get())) {
4130     jio_fprintf(defaultStream::error_stream(),
4131                 "A VM options file may not refer to a VM options file. "
4132                 "Specification of '-XX:VMOptionsFile=<file-name>' in the "
4133                 "options file '%s' in options container '%s' is an error.\n",
4134                 vm_options_file_args->vm_options_file_arg(),
4135                 vm_options_file_args->container_name());
4136     return JNI_EINVAL;
4137   }
4138 
4139   return args_out->insert(args, vm_options_file_args->get(),
4140                           vm_options_file_pos);
4141 }
4142 
4143 // Expand -XX:VMOptionsFile found in args_in as needed.
4144 // mod_args and args_out parameters may return values as needed.
4145 jint Arguments::expand_vm_options_as_needed(const JavaVMInitArgs* args_in,
4146                                             ScopedVMInitArgs* mod_args,
4147                                             JavaVMInitArgs** args_out) {
4148   jint code = match_special_option_and_act(args_in, mod_args);
4149   if (code != JNI_OK) {
4150     return code;
4151   }
4152 
4153   if (mod_args->is_set()) {
4154     // args_in contains -XX:VMOptionsFile and mod_args contains the
4155     // original options from args_in along with the options expanded
4156     // from the VMOptionsFile. Return a short-hand to the caller.
4157     *args_out = mod_args->get();
4158   } else {
4159     *args_out = (JavaVMInitArgs *)args_in;  // no changes so use args_in
4160   }
4161   return JNI_OK;
4162 }
4163 
4164 jint Arguments::match_special_option_and_act(const JavaVMInitArgs* args,
4165                                              ScopedVMInitArgs* args_out) {
4166   // Remaining part of option string
4167   const char* tail;
4168   ScopedVMInitArgs vm_options_file_args(args_out->container_name());
4169 
4170   for (int index = 0; index < args->nOptions; index++) {
4171     const JavaVMOption* option = args->options + index;
4172     if (ArgumentsExt::process_options(option)) {
4173       continue;
4174     }
4175     if (match_option(option, "-XX:Flags=", &tail)) {
4176       Arguments::set_jvm_flags_file(tail);
4177       continue;
4178     }
4179     if (match_option(option, "-XX:VMOptionsFile=", &tail)) {
4180       if (vm_options_file_args.found_vm_options_file_arg()) {
4181         jio_fprintf(defaultStream::error_stream(),
4182                     "The option '%s' is already specified in the options "
4183                     "container '%s' so the specification of '%s' in the "
4184                     "same options container is an error.\n",
4185                     vm_options_file_args.vm_options_file_arg(),
4186                     vm_options_file_args.container_name(),
4187                     option->optionString);
4188         return JNI_EINVAL;
4189       }
4190       vm_options_file_args.set_vm_options_file_arg(option->optionString);
4191       // If there's a VMOptionsFile, parse that
4192       jint code = insert_vm_options_file(args, tail, index,
4193                                          &vm_options_file_args, args_out);
4194       if (code != JNI_OK) {
4195         return code;
4196       }
4197       args_out->set_vm_options_file_arg(vm_options_file_args.vm_options_file_arg());
4198       if (args_out->is_set()) {
4199         // The VMOptions file inserted some options so switch 'args'
4200         // to the new set of options, and continue processing which
4201         // preserves "last option wins" semantics.
4202         args = args_out->get();
4203         // The first option from the VMOptionsFile replaces the
4204         // current option.  So we back track to process the
4205         // replacement option.
4206         index--;
4207       }
4208       continue;
4209     }
4210     if (match_option(option, "-XX:+PrintVMOptions")) {
4211       PrintVMOptions = true;
4212       continue;
4213     }
4214     if (match_option(option, "-XX:-PrintVMOptions")) {
4215       PrintVMOptions = false;
4216       continue;
4217     }
4218     if (match_option(option, "-XX:+IgnoreUnrecognizedVMOptions")) {
4219       IgnoreUnrecognizedVMOptions = true;
4220       continue;
4221     }
4222     if (match_option(option, "-XX:-IgnoreUnrecognizedVMOptions")) {
4223       IgnoreUnrecognizedVMOptions = false;
4224       continue;
4225     }
4226     if (match_option(option, "-XX:+PrintFlagsInitial")) {
4227       CommandLineFlags::printFlags(tty, false);
4228       vm_exit(0);
4229     }
4230     if (match_option(option, "-XX:NativeMemoryTracking", &tail)) {
4231 #if INCLUDE_NMT
4232       // The launcher did not setup nmt environment variable properly.
4233       if (!MemTracker::check_launcher_nmt_support(tail)) {
4234         warning("Native Memory Tracking did not setup properly, using wrong launcher?");
4235       }
4236 
4237       // Verify if nmt option is valid.
4238       if (MemTracker::verify_nmt_option()) {
4239         // Late initialization, still in single-threaded mode.
4240         if (MemTracker::tracking_level() >= NMT_summary) {
4241           MemTracker::init();
4242         }
4243       } else {
4244         vm_exit_during_initialization("Syntax error, expecting -XX:NativeMemoryTracking=[off|summary|detail]", NULL);
4245       }
4246       continue;
4247 #else
4248       jio_fprintf(defaultStream::error_stream(),
4249         "Native Memory Tracking is not supported in this VM\n");
4250       return JNI_ERR;
4251 #endif
4252     }
4253 
4254 #ifndef PRODUCT
4255     if (match_option(option, "-XX:+PrintFlagsWithComments")) {
4256       CommandLineFlags::printFlags(tty, true);
4257       vm_exit(0);
4258     }
4259 #endif
4260   }
4261   return JNI_OK;
4262 }
4263 
4264 static void print_options(const JavaVMInitArgs *args) {
4265   const char* tail;
4266   for (int index = 0; index < args->nOptions; index++) {
4267     const JavaVMOption *option = args->options + index;
4268     if (match_option(option, "-XX:", &tail)) {
4269       logOption(tail);
4270     }
4271   }
4272 }
4273 
4274 bool Arguments::handle_deprecated_print_gc_flags() {
4275   if (PrintGC) {
4276     log_warning(gc)("-XX:+PrintGC is deprecated. Will use -Xlog:gc instead.");
4277   }
4278   if (PrintGCDetails) {
4279     log_warning(gc)("-XX:+PrintGCDetails is deprecated. Will use -Xlog:gc* instead.");
4280   }
4281 
4282   if (_gc_log_filename != NULL) {
4283     // -Xloggc was used to specify a filename
4284     const char* gc_conf = PrintGCDetails ? "gc*" : "gc";
4285 
4286     LogTarget(Error, logging) target;
4287     LogStream errstream(target);
4288     return LogConfiguration::parse_log_arguments(_gc_log_filename, gc_conf, NULL, NULL, &errstream);
4289   } else if (PrintGC || PrintGCDetails) {
4290     LogConfiguration::configure_stdout(LogLevel::Info, !PrintGCDetails, LOG_TAGS(gc));
4291   }
4292   return true;
4293 }
4294 
4295 void Arguments::handle_extra_cms_flags(const char* msg) {
4296   SpecialFlag flag;
4297   const char *flag_name = "UseConcMarkSweepGC";
4298   if (lookup_special_flag(flag_name, flag)) {
4299     handle_aliases_and_deprecation(flag_name, /* print warning */ true);
4300     warning("%s", msg);
4301   }
4302 }
4303 
4304 // Parse entry point called from JNI_CreateJavaVM
4305 
4306 jint Arguments::parse(const JavaVMInitArgs* initial_cmd_args) {
4307   assert(verify_special_jvm_flags(), "deprecated and obsolete flag table inconsistent");
4308 
4309   // Initialize ranges, constraints and writeables
4310   CommandLineFlagRangeList::init();
4311   CommandLineFlagConstraintList::init();
4312   CommandLineFlagWriteableList::init();
4313 
4314   // If flag "-XX:Flags=flags-file" is used it will be the first option to be processed.
4315   const char* hotspotrc = ".hotspotrc";
4316   bool settings_file_specified = false;
4317   bool needs_hotspotrc_warning = false;
4318   ScopedVMInitArgs initial_java_tool_options_args("env_var='JAVA_TOOL_OPTIONS'");
4319   ScopedVMInitArgs initial_java_options_args("env_var='_JAVA_OPTIONS'");
4320 
4321   // Pointers to current working set of containers
4322   JavaVMInitArgs* cur_cmd_args;
4323   JavaVMInitArgs* cur_java_options_args;
4324   JavaVMInitArgs* cur_java_tool_options_args;
4325 
4326   // Containers for modified/expanded options
4327   ScopedVMInitArgs mod_cmd_args("cmd_line_args");
4328   ScopedVMInitArgs mod_java_tool_options_args("env_var='JAVA_TOOL_OPTIONS'");
4329   ScopedVMInitArgs mod_java_options_args("env_var='_JAVA_OPTIONS'");
4330 
4331 
4332   jint code =
4333       parse_java_tool_options_environment_variable(&initial_java_tool_options_args);
4334   if (code != JNI_OK) {
4335     return code;
4336   }
4337 
4338   code = parse_java_options_environment_variable(&initial_java_options_args);
4339   if (code != JNI_OK) {
4340     return code;
4341   }
4342 
4343   code = expand_vm_options_as_needed(initial_java_tool_options_args.get(),
4344                                      &mod_java_tool_options_args,
4345                                      &cur_java_tool_options_args);
4346   if (code != JNI_OK) {
4347     return code;
4348   }
4349 
4350   code = expand_vm_options_as_needed(initial_cmd_args,
4351                                      &mod_cmd_args,
4352                                      &cur_cmd_args);
4353   if (code != JNI_OK) {
4354     return code;
4355   }
4356 
4357   code = expand_vm_options_as_needed(initial_java_options_args.get(),
4358                                      &mod_java_options_args,
4359                                      &cur_java_options_args);
4360   if (code != JNI_OK) {
4361     return code;
4362   }
4363 
4364   const char* flags_file = Arguments::get_jvm_flags_file();
4365   settings_file_specified = (flags_file != NULL);
4366 
4367   if (IgnoreUnrecognizedVMOptions) {
4368     cur_cmd_args->ignoreUnrecognized = true;
4369     cur_java_tool_options_args->ignoreUnrecognized = true;
4370     cur_java_options_args->ignoreUnrecognized = true;
4371   }
4372 
4373   // Parse specified settings file
4374   if (settings_file_specified) {
4375     if (!process_settings_file(flags_file, true,
4376                                cur_cmd_args->ignoreUnrecognized)) {
4377       return JNI_EINVAL;
4378     }
4379   } else {
4380 #ifdef ASSERT
4381     // Parse default .hotspotrc settings file
4382     if (!process_settings_file(".hotspotrc", false,
4383                                cur_cmd_args->ignoreUnrecognized)) {
4384       return JNI_EINVAL;
4385     }
4386 #else
4387     struct stat buf;
4388     if (os::stat(hotspotrc, &buf) == 0) {
4389       needs_hotspotrc_warning = true;
4390     }
4391 #endif
4392   }
4393 
4394   if (PrintVMOptions) {
4395     print_options(cur_java_tool_options_args);
4396     print_options(cur_cmd_args);
4397     print_options(cur_java_options_args);
4398   }
4399 
4400   // Parse JavaVMInitArgs structure passed in, as well as JAVA_TOOL_OPTIONS and _JAVA_OPTIONS
4401   jint result = parse_vm_init_args(cur_java_tool_options_args,
4402                                    cur_java_options_args,
4403                                    cur_cmd_args);
4404 
4405   if (result != JNI_OK) {
4406     return result;
4407   }
4408 
4409   // Call get_shared_archive_path() here, after possible SharedArchiveFile option got parsed.
4410   SharedArchivePath = get_shared_archive_path();
4411   if (SharedArchivePath == NULL) {
4412     return JNI_ENOMEM;
4413   }
4414 
4415   // Set up VerifySharedSpaces
4416   if (FLAG_IS_DEFAULT(VerifySharedSpaces) && SharedArchiveFile != NULL) {
4417     VerifySharedSpaces = true;
4418   }
4419 
4420   // Delay warning until here so that we've had a chance to process
4421   // the -XX:-PrintWarnings flag
4422   if (needs_hotspotrc_warning) {
4423     warning("%s file is present but has been ignored.  "
4424             "Run with -XX:Flags=%s to load the file.",
4425             hotspotrc, hotspotrc);
4426   }
4427 
4428   if (needs_module_property_warning) {
4429     warning("Ignoring system property options whose names match the '-Djdk.module.*'."
4430             " names that are reserved for internal use.");
4431   }
4432 
4433 #if defined(_ALLBSD_SOURCE) || defined(AIX)  // UseLargePages is not yet supported on BSD and AIX.
4434   UNSUPPORTED_OPTION(UseLargePages);
4435 #endif
4436 
4437   ArgumentsExt::report_unsupported_options();
4438 
4439 #ifndef PRODUCT
4440   if (TraceBytecodesAt != 0) {
4441     TraceBytecodes = true;
4442   }
4443   if (CountCompiledCalls) {
4444     if (UseCounterDecay) {
4445       warning("UseCounterDecay disabled because CountCalls is set");
4446       UseCounterDecay = false;
4447     }
4448   }
4449 #endif // PRODUCT
4450 
4451   if (ScavengeRootsInCode == 0) {
4452     if (!FLAG_IS_DEFAULT(ScavengeRootsInCode)) {
4453       warning("Forcing ScavengeRootsInCode non-zero");
4454     }
4455     ScavengeRootsInCode = 1;
4456   }
4457 
4458   if (!handle_deprecated_print_gc_flags()) {
4459     return JNI_EINVAL;
4460   }
4461 
4462   // Set object alignment values.
4463   set_object_alignment();
4464 
4465 #if !INCLUDE_CDS
4466   if (DumpSharedSpaces || RequireSharedSpaces) {
4467     jio_fprintf(defaultStream::error_stream(),
4468       "Shared spaces are not supported in this VM\n");
4469     return JNI_ERR;
4470   }
4471   if ((UseSharedSpaces && FLAG_IS_CMDLINE(UseSharedSpaces)) ||
4472       log_is_enabled(Info, cds)) {
4473     warning("Shared spaces are not supported in this VM");
4474     FLAG_SET_DEFAULT(UseSharedSpaces, false);
4475     LogConfiguration::configure_stdout(LogLevel::Off, true, LOG_TAGS(cds));
4476   }
4477   no_shared_spaces("CDS Disabled");
4478 #endif // INCLUDE_CDS
4479 
4480   return JNI_OK;
4481 }
4482 
4483 jint Arguments::apply_ergo() {
4484   // Set flags based on ergonomics.
4485   set_ergonomics_flags();
4486 
4487 #if INCLUDE_JVMCI
4488   set_jvmci_specific_flags();
4489 #endif
4490 
4491   set_shared_spaces_flags();
4492 
4493 #if defined(SPARC)
4494   // BIS instructions require 'membar' instruction regardless of the number
4495   // of CPUs because in virtualized/container environments which might use only 1
4496   // CPU, BIS instructions may produce incorrect results.
4497 
4498   if (FLAG_IS_DEFAULT(AssumeMP)) {
4499     FLAG_SET_DEFAULT(AssumeMP, true);
4500   }
4501 #endif
4502 
4503   // Check the GC selections again.
4504   if (!check_gc_consistency()) {
4505     return JNI_EINVAL;
4506   }
4507 
4508   if (TieredCompilation) {
4509     set_tiered_flags();
4510   } else {
4511     int max_compilation_policy_choice = 1;
4512 #ifdef COMPILER2
4513     if (is_server_compilation_mode_vm()) {
4514       max_compilation_policy_choice = 2;
4515     }
4516 #endif
4517     // Check if the policy is valid.
4518     if (CompilationPolicyChoice >= max_compilation_policy_choice) {
4519       vm_exit_during_initialization(
4520         "Incompatible compilation policy selected", NULL);
4521     }
4522     // Scale CompileThreshold
4523     // CompileThresholdScaling == 0.0 is equivalent to -Xint and leaves CompileThreshold unchanged.
4524     if (!FLAG_IS_DEFAULT(CompileThresholdScaling) && CompileThresholdScaling > 0.0) {
4525       FLAG_SET_ERGO(intx, CompileThreshold, scaled_compile_threshold(CompileThreshold));
4526     }
4527   }
4528 
4529 #ifdef COMPILER2
4530 #ifndef PRODUCT
4531   if (PrintIdealGraphLevel > 0) {
4532     FLAG_SET_ERGO(bool, PrintIdealGraph, true);
4533   }
4534 #endif
4535 #endif
4536 
4537   // Set heap size based on available physical memory
4538   set_heap_size();
4539 
4540   ArgumentsExt::set_gc_specific_flags();
4541 
4542   // Initialize Metaspace flags and alignments
4543   Metaspace::ergo_initialize();
4544 
4545   // Set bytecode rewriting flags
4546   set_bytecode_flags();
4547 
4548   // Set flags if Aggressive optimization flags (-XX:+AggressiveOpts) enabled
4549   jint code = set_aggressive_opts_flags();
4550   if (code != JNI_OK) {
4551     return code;
4552   }
4553 
4554   // Turn off biased locking for locking debug mode flags,
4555   // which are subtly different from each other but neither works with
4556   // biased locking
4557   if (UseHeavyMonitors
4558 #ifdef COMPILER1
4559       || !UseFastLocking
4560 #endif // COMPILER1
4561 #if INCLUDE_JVMCI
4562       || !JVMCIUseFastLocking
4563 #endif
4564     ) {
4565     if (!FLAG_IS_DEFAULT(UseBiasedLocking) && UseBiasedLocking) {
4566       // flag set to true on command line; warn the user that they
4567       // can't enable biased locking here
4568       warning("Biased Locking is not supported with locking debug flags"
4569               "; ignoring UseBiasedLocking flag." );
4570     }
4571     UseBiasedLocking = false;
4572   }
4573 
4574 #ifdef CC_INTERP
4575   // Clear flags not supported on zero.
4576   FLAG_SET_DEFAULT(ProfileInterpreter, false);
4577   FLAG_SET_DEFAULT(UseBiasedLocking, false);
4578   LP64_ONLY(FLAG_SET_DEFAULT(UseCompressedOops, false));
4579   LP64_ONLY(FLAG_SET_DEFAULT(UseCompressedClassPointers, false));
4580 #endif // CC_INTERP
4581 
4582 #ifdef COMPILER2
4583   if (!EliminateLocks) {
4584     EliminateNestedLocks = false;
4585   }
4586   if (!Inline) {
4587     IncrementalInline = false;
4588   }
4589 #ifndef PRODUCT
4590   if (!IncrementalInline) {
4591     AlwaysIncrementalInline = false;
4592   }
4593 #endif
4594   if (!UseTypeSpeculation && FLAG_IS_DEFAULT(TypeProfileLevel)) {
4595     // nothing to use the profiling, turn if off
4596     FLAG_SET_DEFAULT(TypeProfileLevel, 0);
4597   }
4598 #endif
4599 
4600   if (PrintAssembly && FLAG_IS_DEFAULT(DebugNonSafepoints)) {
4601     warning("PrintAssembly is enabled; turning on DebugNonSafepoints to gain additional output");
4602     DebugNonSafepoints = true;
4603   }
4604 
4605   if (FLAG_IS_CMDLINE(CompressedClassSpaceSize) && !UseCompressedClassPointers) {
4606     warning("Setting CompressedClassSpaceSize has no effect when compressed class pointers are not used");
4607   }
4608 
4609   if (UseOnStackReplacement && !UseLoopCounter) {
4610     warning("On-stack-replacement requires loop counters; enabling loop counters");
4611     FLAG_SET_DEFAULT(UseLoopCounter, true);
4612   }
4613 
4614 #ifndef PRODUCT
4615   if (!LogVMOutput && FLAG_IS_DEFAULT(LogVMOutput)) {
4616     if (use_vm_log()) {
4617       LogVMOutput = true;
4618     }
4619   }
4620 #endif // PRODUCT
4621 
4622   if (PrintCommandLineFlags) {
4623     CommandLineFlags::printSetFlags(tty);
4624   }
4625 
4626   // Apply CPU specific policy for the BiasedLocking
4627   if (UseBiasedLocking) {
4628     if (!VM_Version::use_biased_locking() &&
4629         !(FLAG_IS_CMDLINE(UseBiasedLocking))) {
4630       UseBiasedLocking = false;
4631     }
4632   }
4633 #ifdef COMPILER2
4634   if (!UseBiasedLocking || EmitSync != 0) {
4635     UseOptoBiasInlining = false;
4636   }
4637 #endif
4638 
4639   return JNI_OK;
4640 }
4641 
4642 jint Arguments::adjust_after_os() {
4643   if (UseNUMA) {
4644     if (UseParallelGC || UseParallelOldGC) {
4645       if (FLAG_IS_DEFAULT(MinHeapDeltaBytes)) {
4646          FLAG_SET_DEFAULT(MinHeapDeltaBytes, 64*M);
4647       }
4648     }
4649     // UseNUMAInterleaving is set to ON for all collectors and
4650     // platforms when UseNUMA is set to ON. NUMA-aware collectors
4651     // such as the parallel collector for Linux and Solaris will
4652     // interleave old gen and survivor spaces on top of NUMA
4653     // allocation policy for the eden space.
4654     // Non NUMA-aware collectors such as CMS, G1 and Serial-GC on
4655     // all platforms and ParallelGC on Windows will interleave all
4656     // of the heap spaces across NUMA nodes.
4657     if (FLAG_IS_DEFAULT(UseNUMAInterleaving)) {
4658       FLAG_SET_ERGO(bool, UseNUMAInterleaving, true);
4659     }
4660   }
4661   return JNI_OK;
4662 }
4663 
4664 int Arguments::PropertyList_count(SystemProperty* pl) {
4665   int count = 0;
4666   while(pl != NULL) {
4667     count++;
4668     pl = pl->next();
4669   }
4670   return count;
4671 }
4672 
4673 // Return the number of readable properties.
4674 int Arguments::PropertyList_readable_count(SystemProperty* pl) {
4675   int count = 0;
4676   while(pl != NULL) {
4677     if (pl->is_readable()) {
4678       count++;
4679     }
4680     pl = pl->next();
4681   }
4682   return count;
4683 }
4684 
4685 const char* Arguments::PropertyList_get_value(SystemProperty *pl, const char* key) {
4686   assert(key != NULL, "just checking");
4687   SystemProperty* prop;
4688   for (prop = pl; prop != NULL; prop = prop->next()) {
4689     if (strcmp(key, prop->key()) == 0) return prop->value();
4690   }
4691   return NULL;
4692 }
4693 
4694 // Return the value of the requested property provided that it is a readable property.
4695 const char* Arguments::PropertyList_get_readable_value(SystemProperty *pl, const char* key) {
4696   assert(key != NULL, "just checking");
4697   SystemProperty* prop;
4698   // Return the property value if the keys match and the property is not internal or
4699   // it's the special internal property "jdk.boot.class.path.append".
4700   for (prop = pl; prop != NULL; prop = prop->next()) {
4701     if (strcmp(key, prop->key()) == 0) {
4702       if (!prop->internal()) {
4703         return prop->value();
4704       } else if (strcmp(key, "jdk.boot.class.path.append") == 0) {
4705         return prop->value();
4706       } else {
4707         // Property is internal and not jdk.boot.class.path.append so return NULL.
4708         return NULL;
4709       }
4710     }
4711   }
4712   return NULL;
4713 }
4714 
4715 const char* Arguments::PropertyList_get_key_at(SystemProperty *pl, int index) {
4716   int count = 0;
4717   const char* ret_val = NULL;
4718 
4719   while(pl != NULL) {
4720     if(count >= index) {
4721       ret_val = pl->key();
4722       break;
4723     }
4724     count++;
4725     pl = pl->next();
4726   }
4727 
4728   return ret_val;
4729 }
4730 
4731 char* Arguments::PropertyList_get_value_at(SystemProperty* pl, int index) {
4732   int count = 0;
4733   char* ret_val = NULL;
4734 
4735   while(pl != NULL) {
4736     if(count >= index) {
4737       ret_val = pl->value();
4738       break;
4739     }
4740     count++;
4741     pl = pl->next();
4742   }
4743 
4744   return ret_val;
4745 }
4746 
4747 void Arguments::PropertyList_add(SystemProperty** plist, SystemProperty *new_p) {
4748   SystemProperty* p = *plist;
4749   if (p == NULL) {
4750     *plist = new_p;
4751   } else {
4752     while (p->next() != NULL) {
4753       p = p->next();
4754     }
4755     p->set_next(new_p);
4756   }
4757 }
4758 
4759 void Arguments::PropertyList_add(SystemProperty** plist, const char* k, const char* v,
4760                                  bool writeable, bool internal) {
4761   if (plist == NULL)
4762     return;
4763 
4764   SystemProperty* new_p = new SystemProperty(k, v, writeable, internal);
4765   PropertyList_add(plist, new_p);
4766 }
4767 
4768 void Arguments::PropertyList_add(SystemProperty *element) {
4769   PropertyList_add(&_system_properties, element);
4770 }
4771 
4772 // This add maintains unique property key in the list.
4773 void Arguments::PropertyList_unique_add(SystemProperty** plist, const char* k, const char* v,
4774                                         PropertyAppendable append, PropertyWriteable writeable,
4775                                         PropertyInternal internal) {
4776   if (plist == NULL)
4777     return;
4778 
4779   // If property key exist then update with new value.
4780   SystemProperty* prop;
4781   for (prop = *plist; prop != NULL; prop = prop->next()) {
4782     if (strcmp(k, prop->key()) == 0) {
4783       if (append == AppendProperty) {
4784         prop->append_value(v);
4785       } else {
4786         prop->set_value(v);
4787       }
4788       return;
4789     }
4790   }
4791 
4792   PropertyList_add(plist, k, v, writeable == WriteableProperty, internal == InternalProperty);
4793 }
4794 
4795 // Copies src into buf, replacing "%%" with "%" and "%p" with pid
4796 // Returns true if all of the source pointed by src has been copied over to
4797 // the destination buffer pointed by buf. Otherwise, returns false.
4798 // Notes:
4799 // 1. If the length (buflen) of the destination buffer excluding the
4800 // NULL terminator character is not long enough for holding the expanded
4801 // pid characters, it also returns false instead of returning the partially
4802 // expanded one.
4803 // 2. The passed in "buflen" should be large enough to hold the null terminator.
4804 bool Arguments::copy_expand_pid(const char* src, size_t srclen,
4805                                 char* buf, size_t buflen) {
4806   const char* p = src;
4807   char* b = buf;
4808   const char* src_end = &src[srclen];
4809   char* buf_end = &buf[buflen - 1];
4810 
4811   while (p < src_end && b < buf_end) {
4812     if (*p == '%') {
4813       switch (*(++p)) {
4814       case '%':         // "%%" ==> "%"
4815         *b++ = *p++;
4816         break;
4817       case 'p':  {       //  "%p" ==> current process id
4818         // buf_end points to the character before the last character so
4819         // that we could write '\0' to the end of the buffer.
4820         size_t buf_sz = buf_end - b + 1;
4821         int ret = jio_snprintf(b, buf_sz, "%d", os::current_process_id());
4822 
4823         // if jio_snprintf fails or the buffer is not long enough to hold
4824         // the expanded pid, returns false.
4825         if (ret < 0 || ret >= (int)buf_sz) {
4826           return false;
4827         } else {
4828           b += ret;
4829           assert(*b == '\0', "fail in copy_expand_pid");
4830           if (p == src_end && b == buf_end + 1) {
4831             // reach the end of the buffer.
4832             return true;
4833           }
4834         }
4835         p++;
4836         break;
4837       }
4838       default :
4839         *b++ = '%';
4840       }
4841     } else {
4842       *b++ = *p++;
4843     }
4844   }
4845   *b = '\0';
4846   return (p == src_end); // return false if not all of the source was copied
4847 }