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