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