1 /*
   2  * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/javaAssertions.hpp"
  27 #include "compiler/compilerOracle.hpp"
  28 #include "memory/allocation.inline.hpp"
  29 #include "memory/cardTableRS.hpp"
  30 #include "memory/referenceProcessor.hpp"
  31 #include "memory/universe.inline.hpp"
  32 #include "oops/oop.inline.hpp"
  33 #include "prims/jvmtiExport.hpp"
  34 #include "runtime/arguments.hpp"
  35 #include "runtime/globals_extension.hpp"
  36 #include "runtime/java.hpp"
  37 #include "services/management.hpp"
  38 #include "services/memTracker.hpp"
  39 #include "utilities/defaultStream.hpp"
  40 #include "utilities/taskqueue.hpp"
  41 #ifdef TARGET_OS_FAMILY_linux
  42 # include "os_linux.inline.hpp"
  43 #endif
  44 #ifdef TARGET_OS_FAMILY_solaris
  45 # include "os_solaris.inline.hpp"
  46 #endif
  47 #ifdef TARGET_OS_FAMILY_windows
  48 # include "os_windows.inline.hpp"
  49 #endif
  50 #ifdef TARGET_OS_FAMILY_bsd
  51 # include "os_bsd.inline.hpp"
  52 #endif
  53 #ifndef SERIALGC
  54 #include "gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.hpp"
  55 #endif
  56 
  57 // Note: This is a special bug reporting site for the JVM
  58 #define DEFAULT_VENDOR_URL_BUG "http://bugreport.sun.com/bugreport/crash.jsp"
  59 #define DEFAULT_JAVA_LAUNCHER  "generic"
  60 
  61 char**  Arguments::_jvm_flags_array             = NULL;
  62 int     Arguments::_num_jvm_flags               = 0;
  63 char**  Arguments::_jvm_args_array              = NULL;
  64 int     Arguments::_num_jvm_args                = 0;
  65 char*  Arguments::_java_command                 = NULL;
  66 SystemProperty* Arguments::_system_properties   = NULL;
  67 const char*  Arguments::_gc_log_filename        = NULL;
  68 bool   Arguments::_has_profile                  = false;
  69 bool   Arguments::_has_alloc_profile            = false;
  70 uintx  Arguments::_min_heap_size                = 0;
  71 Arguments::Mode Arguments::_mode                = _mixed;
  72 bool   Arguments::_java_compiler                = false;
  73 bool   Arguments::_xdebug_mode                  = false;
  74 const char*  Arguments::_java_vendor_url_bug    = DEFAULT_VENDOR_URL_BUG;
  75 const char*  Arguments::_sun_java_launcher      = DEFAULT_JAVA_LAUNCHER;
  76 int    Arguments::_sun_java_launcher_pid        = -1;
  77 bool   Arguments::_created_by_gamma_launcher    = false;
  78 
  79 // These parameters are reset in method parse_vm_init_args(JavaVMInitArgs*)
  80 bool   Arguments::_AlwaysCompileLoopMethods     = AlwaysCompileLoopMethods;
  81 bool   Arguments::_UseOnStackReplacement        = UseOnStackReplacement;
  82 bool   Arguments::_BackgroundCompilation        = BackgroundCompilation;
  83 bool   Arguments::_ClipInlining                 = ClipInlining;
  84 
  85 char*  Arguments::SharedArchivePath             = NULL;
  86 
  87 AgentLibraryList Arguments::_libraryList;
  88 AgentLibraryList Arguments::_agentList;
  89 
  90 abort_hook_t     Arguments::_abort_hook         = NULL;
  91 exit_hook_t      Arguments::_exit_hook          = NULL;
  92 vfprintf_hook_t  Arguments::_vfprintf_hook      = NULL;
  93 
  94 
  95 SystemProperty *Arguments::_java_ext_dirs = NULL;
  96 SystemProperty *Arguments::_java_endorsed_dirs = NULL;
  97 SystemProperty *Arguments::_sun_boot_library_path = NULL;
  98 SystemProperty *Arguments::_java_library_path = NULL;
  99 SystemProperty *Arguments::_java_home = NULL;
 100 SystemProperty *Arguments::_java_class_path = NULL;
 101 SystemProperty *Arguments::_sun_boot_class_path = NULL;
 102 
 103 char* Arguments::_meta_index_path = NULL;
 104 char* Arguments::_meta_index_dir = NULL;
 105 
 106 // Check if head of 'option' matches 'name', and sets 'tail' remaining part of option string
 107 
 108 static bool match_option(const JavaVMOption *option, const char* name,
 109                          const char** tail) {
 110   int len = (int)strlen(name);
 111   if (strncmp(option->optionString, name, len) == 0) {
 112     *tail = option->optionString + len;
 113     return true;
 114   } else {
 115     return false;
 116   }
 117 }
 118 
 119 static void logOption(const char* opt) {
 120   if (PrintVMOptions) {
 121     jio_fprintf(defaultStream::output_stream(), "VM option '%s'\n", opt);
 122   }
 123 }
 124 
 125 // Process java launcher properties.
 126 void Arguments::process_sun_java_launcher_properties(JavaVMInitArgs* args) {
 127   // See if sun.java.launcher or sun.java.launcher.pid is defined.
 128   // Must do this before setting up other system properties,
 129   // as some of them may depend on launcher type.
 130   for (int index = 0; index < args->nOptions; index++) {
 131     const JavaVMOption* option = args->options + index;
 132     const char* tail;
 133 
 134     if (match_option(option, "-Dsun.java.launcher=", &tail)) {
 135       process_java_launcher_argument(tail, option->extraInfo);
 136       continue;
 137     }
 138     if (match_option(option, "-Dsun.java.launcher.pid=", &tail)) {
 139       _sun_java_launcher_pid = atoi(tail);
 140       continue;
 141     }
 142   }
 143 }
 144 
 145 // Initialize system properties key and value.
 146 void Arguments::init_system_properties() {
 147 
 148   PropertyList_add(&_system_properties, new SystemProperty("java.vm.specification.name",
 149                                                                  "Java Virtual Machine Specification",  false));
 150   PropertyList_add(&_system_properties, new SystemProperty("java.vm.version", VM_Version::vm_release(),  false));
 151   PropertyList_add(&_system_properties, new SystemProperty("java.vm.name", VM_Version::vm_name(),  false));
 152   PropertyList_add(&_system_properties, new SystemProperty("java.vm.info", VM_Version::vm_info_string(),  true));
 153 
 154   // following are JVMTI agent writeable properties.
 155   // Properties values are set to NULL and they are
 156   // os specific they are initialized in os::init_system_properties_values().
 157   _java_ext_dirs = new SystemProperty("java.ext.dirs", NULL,  true);
 158   _java_endorsed_dirs = new SystemProperty("java.endorsed.dirs", NULL,  true);
 159   _sun_boot_library_path = new SystemProperty("sun.boot.library.path", NULL,  true);
 160   _java_library_path = new SystemProperty("java.library.path", NULL,  true);
 161   _java_home =  new SystemProperty("java.home", NULL,  true);
 162   _sun_boot_class_path = new SystemProperty("sun.boot.class.path", NULL,  true);
 163 
 164   _java_class_path = new SystemProperty("java.class.path", "",  true);
 165 
 166   // Add to System Property list.
 167   PropertyList_add(&_system_properties, _java_ext_dirs);
 168   PropertyList_add(&_system_properties, _java_endorsed_dirs);
 169   PropertyList_add(&_system_properties, _sun_boot_library_path);
 170   PropertyList_add(&_system_properties, _java_library_path);
 171   PropertyList_add(&_system_properties, _java_home);
 172   PropertyList_add(&_system_properties, _java_class_path);
 173   PropertyList_add(&_system_properties, _sun_boot_class_path);
 174 
 175   // Set OS specific system properties values
 176   os::init_system_properties_values();
 177 }
 178 
 179 
 180   // Update/Initialize System properties after JDK version number is known
 181 void Arguments::init_version_specific_system_properties() {
 182   enum { bufsz = 16 };
 183   char buffer[bufsz];
 184   const char* spec_vendor = "Sun Microsystems Inc.";
 185   uint32_t spec_version = 0;
 186 
 187   if (JDK_Version::is_gte_jdk17x_version()) {
 188     spec_vendor = "Oracle Corporation";
 189     spec_version = JDK_Version::current().major_version();
 190   }
 191   jio_snprintf(buffer, bufsz, "1." UINT32_FORMAT, spec_version);
 192 
 193   PropertyList_add(&_system_properties,
 194       new SystemProperty("java.vm.specification.vendor",  spec_vendor, false));
 195   PropertyList_add(&_system_properties,
 196       new SystemProperty("java.vm.specification.version", buffer, false));
 197   PropertyList_add(&_system_properties,
 198       new SystemProperty("java.vm.vendor", VM_Version::vm_vendor(),  false));
 199 }
 200 
 201 /**
 202  * Provide a slightly more user-friendly way of eliminating -XX flags.
 203  * When a flag is eliminated, it can be added to this list in order to
 204  * continue accepting this flag on the command-line, while issuing a warning
 205  * and ignoring the value.  Once the JDK version reaches the 'accept_until'
 206  * limit, we flatly refuse to admit the existence of the flag.  This allows
 207  * a flag to die correctly over JDK releases using HSX.
 208  */
 209 typedef struct {
 210   const char* name;
 211   JDK_Version obsoleted_in; // when the flag went away
 212   JDK_Version accept_until; // which version to start denying the existence
 213 } ObsoleteFlag;
 214 
 215 static ObsoleteFlag obsolete_jvm_flags[] = {
 216   { "UseTrainGC",                    JDK_Version::jdk(5), JDK_Version::jdk(7) },
 217   { "UseSpecialLargeObjectHandling", JDK_Version::jdk(5), JDK_Version::jdk(7) },
 218   { "UseOversizedCarHandling",       JDK_Version::jdk(5), JDK_Version::jdk(7) },
 219   { "TraceCarAllocation",            JDK_Version::jdk(5), JDK_Version::jdk(7) },
 220   { "PrintTrainGCProcessingStats",   JDK_Version::jdk(5), JDK_Version::jdk(7) },
 221   { "LogOfCarSpaceSize",             JDK_Version::jdk(5), JDK_Version::jdk(7) },
 222   { "OversizedCarThreshold",         JDK_Version::jdk(5), JDK_Version::jdk(7) },
 223   { "MinTickInterval",               JDK_Version::jdk(5), JDK_Version::jdk(7) },
 224   { "DefaultTickInterval",           JDK_Version::jdk(5), JDK_Version::jdk(7) },
 225   { "MaxTickInterval",               JDK_Version::jdk(5), JDK_Version::jdk(7) },
 226   { "DelayTickAdjustment",           JDK_Version::jdk(5), JDK_Version::jdk(7) },
 227   { "ProcessingToTenuringRatio",     JDK_Version::jdk(5), JDK_Version::jdk(7) },
 228   { "MinTrainLength",                JDK_Version::jdk(5), JDK_Version::jdk(7) },
 229   { "AppendRatio",         JDK_Version::jdk_update(6,10), JDK_Version::jdk(7) },
 230   { "DefaultMaxRAM",       JDK_Version::jdk_update(6,18), JDK_Version::jdk(7) },
 231   { "DefaultInitialRAMFraction",
 232                            JDK_Version::jdk_update(6,18), JDK_Version::jdk(7) },
 233   { "UseDepthFirstScavengeOrder",
 234                            JDK_Version::jdk_update(6,22), JDK_Version::jdk(7) },
 235   { "HandlePromotionFailure",
 236                            JDK_Version::jdk_update(6,24), JDK_Version::jdk(8) },
 237   { "MaxLiveObjectEvacuationRatio",
 238                            JDK_Version::jdk_update(6,24), JDK_Version::jdk(8) },
 239   { "ForceSharedSpaces",   JDK_Version::jdk_update(6,25), JDK_Version::jdk(8) },
 240   { "UseParallelOldGCCompacting",
 241                            JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
 242   { "UseParallelDensePrefixUpdate",
 243                            JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
 244   { "UseParallelOldGCDensePrefix",
 245                            JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
 246   { "AllowTransitionalJSR292",       JDK_Version::jdk(7), JDK_Version::jdk(8) },
 247   { "UseCompressedStrings",          JDK_Version::jdk(7), JDK_Version::jdk(8) },
 248   { "CMSPermGenPrecleaningEnabled", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 249   { "CMSTriggerPermRatio", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 250   { "CMSInitiatingPermOccupancyFraction", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 251   { "AdaptivePermSizeWeight", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 252   { "PermGenPadding", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 253   { "PermMarkSweepDeadRatio", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 254   { "PermSize", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 255   { "MaxPermSize", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 256   { "MinPermHeapExpansion", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 257   { "MaxPermHeapExpansion", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 258   { "CMSRevisitStackSize",           JDK_Version::jdk(8), JDK_Version::jdk(9) },
 259   { "PrintRevisitStats",             JDK_Version::jdk(8), JDK_Version::jdk(9) },
 260 #ifdef PRODUCT
 261   { "DesiredMethodLimit",
 262                            JDK_Version::jdk_update(7, 2), JDK_Version::jdk(8) },
 263 #endif // PRODUCT
 264   { NULL, JDK_Version(0), JDK_Version(0) }
 265 };
 266 
 267 // Returns true if the flag is obsolete and fits into the range specified
 268 // for being ignored.  In the case that the flag is ignored, the 'version'
 269 // value is filled in with the version number when the flag became
 270 // obsolete so that that value can be displayed to the user.
 271 bool Arguments::is_newly_obsolete(const char *s, JDK_Version* version) {
 272   int i = 0;
 273   assert(version != NULL, "Must provide a version buffer");
 274   while (obsolete_jvm_flags[i].name != NULL) {
 275     const ObsoleteFlag& flag_status = obsolete_jvm_flags[i];
 276     // <flag>=xxx form
 277     // [-|+]<flag> form
 278     if ((strncmp(flag_status.name, s, strlen(flag_status.name)) == 0) ||
 279         ((s[0] == '+' || s[0] == '-') &&
 280         (strncmp(flag_status.name, &s[1], strlen(flag_status.name)) == 0))) {
 281       if (JDK_Version::current().compare(flag_status.accept_until) == -1) {
 282           *version = flag_status.obsoleted_in;
 283           return true;
 284       }
 285     }
 286     i++;
 287   }
 288   return false;
 289 }
 290 
 291 // Constructs the system class path (aka boot class path) from the following
 292 // components, in order:
 293 //
 294 //     prefix           // from -Xbootclasspath/p:...
 295 //     endorsed         // the expansion of -Djava.endorsed.dirs=...
 296 //     base             // from os::get_system_properties() or -Xbootclasspath=
 297 //     suffix           // from -Xbootclasspath/a:...
 298 //
 299 // java.endorsed.dirs is a list of directories; any jar or zip files in the
 300 // directories are added to the sysclasspath just before the base.
 301 //
 302 // This could be AllStatic, but it isn't needed after argument processing is
 303 // complete.
 304 class SysClassPath: public StackObj {
 305 public:
 306   SysClassPath(const char* base);
 307   ~SysClassPath();
 308 
 309   inline void set_base(const char* base);
 310   inline void add_prefix(const char* prefix);
 311   inline void add_suffix_to_prefix(const char* suffix);
 312   inline void add_suffix(const char* suffix);
 313   inline void reset_path(const char* base);
 314 
 315   // Expand the jar/zip files in each directory listed by the java.endorsed.dirs
 316   // property.  Must be called after all command-line arguments have been
 317   // processed (in particular, -Djava.endorsed.dirs=...) and before calling
 318   // combined_path().
 319   void expand_endorsed();
 320 
 321   inline const char* get_base()     const { return _items[_scp_base]; }
 322   inline const char* get_prefix()   const { return _items[_scp_prefix]; }
 323   inline const char* get_suffix()   const { return _items[_scp_suffix]; }
 324   inline const char* get_endorsed() const { return _items[_scp_endorsed]; }
 325 
 326   // Combine all the components into a single c-heap-allocated string; caller
 327   // must free the string if/when no longer needed.
 328   char* combined_path();
 329 
 330 private:
 331   // Utility routines.
 332   static char* add_to_path(const char* path, const char* str, bool prepend);
 333   static char* add_jars_to_path(char* path, const char* directory);
 334 
 335   inline void reset_item_at(int index);
 336 
 337   // Array indices for the items that make up the sysclasspath.  All except the
 338   // base are allocated in the C heap and freed by this class.
 339   enum {
 340     _scp_prefix,        // from -Xbootclasspath/p:...
 341     _scp_endorsed,      // the expansion of -Djava.endorsed.dirs=...
 342     _scp_base,          // the default sysclasspath
 343     _scp_suffix,        // from -Xbootclasspath/a:...
 344     _scp_nitems         // the number of items, must be last.
 345   };
 346 
 347   const char* _items[_scp_nitems];
 348   DEBUG_ONLY(bool _expansion_done;)
 349 };
 350 
 351 SysClassPath::SysClassPath(const char* base) {
 352   memset(_items, 0, sizeof(_items));
 353   _items[_scp_base] = base;
 354   DEBUG_ONLY(_expansion_done = false;)
 355 }
 356 
 357 SysClassPath::~SysClassPath() {
 358   // Free everything except the base.
 359   for (int i = 0; i < _scp_nitems; ++i) {
 360     if (i != _scp_base) reset_item_at(i);
 361   }
 362   DEBUG_ONLY(_expansion_done = false;)
 363 }
 364 
 365 inline void SysClassPath::set_base(const char* base) {
 366   _items[_scp_base] = base;
 367 }
 368 
 369 inline void SysClassPath::add_prefix(const char* prefix) {
 370   _items[_scp_prefix] = add_to_path(_items[_scp_prefix], prefix, true);
 371 }
 372 
 373 inline void SysClassPath::add_suffix_to_prefix(const char* suffix) {
 374   _items[_scp_prefix] = add_to_path(_items[_scp_prefix], suffix, false);
 375 }
 376 
 377 inline void SysClassPath::add_suffix(const char* suffix) {
 378   _items[_scp_suffix] = add_to_path(_items[_scp_suffix], suffix, false);
 379 }
 380 
 381 inline void SysClassPath::reset_item_at(int index) {
 382   assert(index < _scp_nitems && index != _scp_base, "just checking");
 383   if (_items[index] != NULL) {
 384     FREE_C_HEAP_ARRAY(char, _items[index], mtInternal);
 385     _items[index] = NULL;
 386   }
 387 }
 388 
 389 inline void SysClassPath::reset_path(const char* base) {
 390   // Clear the prefix and suffix.
 391   reset_item_at(_scp_prefix);
 392   reset_item_at(_scp_suffix);
 393   set_base(base);
 394 }
 395 
 396 //------------------------------------------------------------------------------
 397 
 398 void SysClassPath::expand_endorsed() {
 399   assert(_items[_scp_endorsed] == NULL, "can only be called once.");
 400 
 401   const char* path = Arguments::get_property("java.endorsed.dirs");
 402   if (path == NULL) {
 403     path = Arguments::get_endorsed_dir();
 404     assert(path != NULL, "no default for java.endorsed.dirs");
 405   }
 406 
 407   char* expanded_path = NULL;
 408   const char separator = *os::path_separator();
 409   const char* const end = path + strlen(path);
 410   while (path < end) {
 411     const char* tmp_end = strchr(path, separator);
 412     if (tmp_end == NULL) {
 413       expanded_path = add_jars_to_path(expanded_path, path);
 414       path = end;
 415     } else {
 416       char* dirpath = NEW_C_HEAP_ARRAY(char, tmp_end - path + 1, mtInternal);
 417       memcpy(dirpath, path, tmp_end - path);
 418       dirpath[tmp_end - path] = '\0';
 419       expanded_path = add_jars_to_path(expanded_path, dirpath);
 420       FREE_C_HEAP_ARRAY(char, dirpath, mtInternal);
 421       path = tmp_end + 1;
 422     }
 423   }
 424   _items[_scp_endorsed] = expanded_path;
 425   DEBUG_ONLY(_expansion_done = true;)
 426 }
 427 
 428 // Combine the bootclasspath elements, some of which may be null, into a single
 429 // c-heap-allocated string.
 430 char* SysClassPath::combined_path() {
 431   assert(_items[_scp_base] != NULL, "empty default sysclasspath");
 432   assert(_expansion_done, "must call expand_endorsed() first.");
 433 
 434   size_t lengths[_scp_nitems];
 435   size_t total_len = 0;
 436 
 437   const char separator = *os::path_separator();
 438 
 439   // Get the lengths.
 440   int i;
 441   for (i = 0; i < _scp_nitems; ++i) {
 442     if (_items[i] != NULL) {
 443       lengths[i] = strlen(_items[i]);
 444       // Include space for the separator char (or a NULL for the last item).
 445       total_len += lengths[i] + 1;
 446     }
 447   }
 448   assert(total_len > 0, "empty sysclasspath not allowed");
 449 
 450   // Copy the _items to a single string.
 451   char* cp = NEW_C_HEAP_ARRAY(char, total_len, mtInternal);
 452   char* cp_tmp = cp;
 453   for (i = 0; i < _scp_nitems; ++i) {
 454     if (_items[i] != NULL) {
 455       memcpy(cp_tmp, _items[i], lengths[i]);
 456       cp_tmp += lengths[i];
 457       *cp_tmp++ = separator;
 458     }
 459   }
 460   *--cp_tmp = '\0';     // Replace the extra separator.
 461   return cp;
 462 }
 463 
 464 // Note:  path must be c-heap-allocated (or NULL); it is freed if non-null.
 465 char*
 466 SysClassPath::add_to_path(const char* path, const char* str, bool prepend) {
 467   char *cp;
 468 
 469   assert(str != NULL, "just checking");
 470   if (path == NULL) {
 471     size_t len = strlen(str) + 1;
 472     cp = NEW_C_HEAP_ARRAY(char, len, mtInternal);
 473     memcpy(cp, str, len);                       // copy the trailing null
 474   } else {
 475     const char separator = *os::path_separator();
 476     size_t old_len = strlen(path);
 477     size_t str_len = strlen(str);
 478     size_t len = old_len + str_len + 2;
 479 
 480     if (prepend) {
 481       cp = NEW_C_HEAP_ARRAY(char, len, mtInternal);
 482       char* cp_tmp = cp;
 483       memcpy(cp_tmp, str, str_len);
 484       cp_tmp += str_len;
 485       *cp_tmp = separator;
 486       memcpy(++cp_tmp, path, old_len + 1);      // copy the trailing null
 487       FREE_C_HEAP_ARRAY(char, path, mtInternal);
 488     } else {
 489       cp = REALLOC_C_HEAP_ARRAY(char, path, len, mtInternal);
 490       char* cp_tmp = cp + old_len;
 491       *cp_tmp = separator;
 492       memcpy(++cp_tmp, str, str_len + 1);       // copy the trailing null
 493     }
 494   }
 495   return cp;
 496 }
 497 
 498 // Scan the directory and append any jar or zip files found to path.
 499 // Note:  path must be c-heap-allocated (or NULL); it is freed if non-null.
 500 char* SysClassPath::add_jars_to_path(char* path, const char* directory) {
 501   DIR* dir = os::opendir(directory);
 502   if (dir == NULL) return path;
 503 
 504   char dir_sep[2] = { '\0', '\0' };
 505   size_t directory_len = strlen(directory);
 506   const char fileSep = *os::file_separator();
 507   if (directory[directory_len - 1] != fileSep) dir_sep[0] = fileSep;
 508 
 509   /* Scan the directory for jars/zips, appending them to path. */
 510   struct dirent *entry;
 511   char *dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory), mtInternal);
 512   while ((entry = os::readdir(dir, (dirent *) dbuf)) != NULL) {
 513     const char* name = entry->d_name;
 514     const char* ext = name + strlen(name) - 4;
 515     bool isJarOrZip = ext > name &&
 516       (os::file_name_strcmp(ext, ".jar") == 0 ||
 517        os::file_name_strcmp(ext, ".zip") == 0);
 518     if (isJarOrZip) {
 519       char* jarpath = NEW_C_HEAP_ARRAY(char, directory_len + 2 + strlen(name), mtInternal);
 520       sprintf(jarpath, "%s%s%s", directory, dir_sep, name);
 521       path = add_to_path(path, jarpath, false);
 522       FREE_C_HEAP_ARRAY(char, jarpath, mtInternal);
 523     }
 524   }
 525   FREE_C_HEAP_ARRAY(char, dbuf, mtInternal);
 526   os::closedir(dir);
 527   return path;
 528 }
 529 
 530 // Parses a memory size specification string.
 531 static bool atomull(const char *s, julong* result) {
 532   julong n = 0;
 533   int args_read = sscanf(s, os::julong_format_specifier(), &n);
 534   if (args_read != 1) {
 535     return false;
 536   }
 537   while (*s != '\0' && isdigit(*s)) {
 538     s++;
 539   }
 540   // 4705540: illegal if more characters are found after the first non-digit
 541   if (strlen(s) > 1) {
 542     return false;
 543   }
 544   switch (*s) {
 545     case 'T': case 't':
 546       *result = n * G * K;
 547       // Check for overflow.
 548       if (*result/((julong)G * K) != n) return false;
 549       return true;
 550     case 'G': case 'g':
 551       *result = n * G;
 552       if (*result/G != n) return false;
 553       return true;
 554     case 'M': case 'm':
 555       *result = n * M;
 556       if (*result/M != n) return false;
 557       return true;
 558     case 'K': case 'k':
 559       *result = n * K;
 560       if (*result/K != n) return false;
 561       return true;
 562     case '\0':
 563       *result = n;
 564       return true;
 565     default:
 566       return false;
 567   }
 568 }
 569 
 570 Arguments::ArgsRange Arguments::check_memory_size(julong size, julong min_size) {
 571   if (size < min_size) return arg_too_small;
 572   // Check that size will fit in a size_t (only relevant on 32-bit)
 573   if (size > max_uintx) return arg_too_big;
 574   return arg_in_range;
 575 }
 576 
 577 // Describe an argument out of range error
 578 void Arguments::describe_range_error(ArgsRange errcode) {
 579   switch(errcode) {
 580   case arg_too_big:
 581     jio_fprintf(defaultStream::error_stream(),
 582                 "The specified size exceeds the maximum "
 583                 "representable size.\n");
 584     break;
 585   case arg_too_small:
 586   case arg_unreadable:
 587   case arg_in_range:
 588     // do nothing for now
 589     break;
 590   default:
 591     ShouldNotReachHere();
 592   }
 593 }
 594 
 595 static bool set_bool_flag(char* name, bool value, FlagValueOrigin origin) {
 596   return CommandLineFlags::boolAtPut(name, &value, origin);
 597 }
 598 
 599 static bool set_fp_numeric_flag(char* name, char* value, FlagValueOrigin origin) {
 600   double v;
 601   if (sscanf(value, "%lf", &v) != 1) {
 602     return false;
 603   }
 604 
 605   if (CommandLineFlags::doubleAtPut(name, &v, origin)) {
 606     return true;
 607   }
 608   return false;
 609 }
 610 
 611 static bool set_numeric_flag(char* name, char* value, FlagValueOrigin origin) {
 612   julong v;
 613   intx intx_v;
 614   bool is_neg = false;
 615   // Check the sign first since atomull() parses only unsigned values.
 616   if (*value == '-') {
 617     if (!CommandLineFlags::intxAt(name, &intx_v)) {
 618       return false;
 619     }
 620     value++;
 621     is_neg = true;
 622   }
 623   if (!atomull(value, &v)) {
 624     return false;
 625   }
 626   intx_v = (intx) v;
 627   if (is_neg) {
 628     intx_v = -intx_v;
 629   }
 630   if (CommandLineFlags::intxAtPut(name, &intx_v, origin)) {
 631     return true;
 632   }
 633   uintx uintx_v = (uintx) v;
 634   if (!is_neg && CommandLineFlags::uintxAtPut(name, &uintx_v, origin)) {
 635     return true;
 636   }
 637   uint64_t uint64_t_v = (uint64_t) v;
 638   if (!is_neg && CommandLineFlags::uint64_tAtPut(name, &uint64_t_v, origin)) {
 639     return true;
 640   }
 641   return false;
 642 }
 643 
 644 static bool set_string_flag(char* name, const char* value, FlagValueOrigin origin) {
 645   if (!CommandLineFlags::ccstrAtPut(name, &value, origin))  return false;
 646   // Contract:  CommandLineFlags always returns a pointer that needs freeing.
 647   FREE_C_HEAP_ARRAY(char, value, mtInternal);
 648   return true;
 649 }
 650 
 651 static bool append_to_string_flag(char* name, const char* new_value, FlagValueOrigin origin) {
 652   const char* old_value = "";
 653   if (!CommandLineFlags::ccstrAt(name, &old_value))  return false;
 654   size_t old_len = old_value != NULL ? strlen(old_value) : 0;
 655   size_t new_len = strlen(new_value);
 656   const char* value;
 657   char* free_this_too = NULL;
 658   if (old_len == 0) {
 659     value = new_value;
 660   } else if (new_len == 0) {
 661     value = old_value;
 662   } else {
 663     char* buf = NEW_C_HEAP_ARRAY(char, old_len + 1 + new_len + 1, mtInternal);
 664     // each new setting adds another LINE to the switch:
 665     sprintf(buf, "%s\n%s", old_value, new_value);
 666     value = buf;
 667     free_this_too = buf;
 668   }
 669   (void) CommandLineFlags::ccstrAtPut(name, &value, origin);
 670   // CommandLineFlags always returns a pointer that needs freeing.
 671   FREE_C_HEAP_ARRAY(char, value, mtInternal);
 672   if (free_this_too != NULL) {
 673     // CommandLineFlags made its own copy, so I must delete my own temp. buffer.
 674     FREE_C_HEAP_ARRAY(char, free_this_too, mtInternal);
 675   }
 676   return true;
 677 }
 678 
 679 bool Arguments::parse_argument(const char* arg, FlagValueOrigin origin) {
 680 
 681   // range of acceptable characters spelled out for portability reasons
 682 #define NAME_RANGE  "[abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_]"
 683 #define BUFLEN 255
 684   char name[BUFLEN+1];
 685   char dummy;
 686 
 687   if (sscanf(arg, "-%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
 688     return set_bool_flag(name, false, origin);
 689   }
 690   if (sscanf(arg, "+%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
 691     return set_bool_flag(name, true, origin);
 692   }
 693 
 694   char punct;
 695   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "%c", name, &punct) == 2 && punct == '=') {
 696     const char* value = strchr(arg, '=') + 1;
 697     Flag* flag = Flag::find_flag(name, strlen(name));
 698     if (flag != NULL && flag->is_ccstr()) {
 699       if (flag->ccstr_accumulates()) {
 700         return append_to_string_flag(name, value, origin);
 701       } else {
 702         if (value[0] == '\0') {
 703           value = NULL;
 704         }
 705         return set_string_flag(name, value, origin);
 706       }
 707     }
 708   }
 709 
 710   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE ":%c", name, &punct) == 2 && punct == '=') {
 711     const char* value = strchr(arg, '=') + 1;
 712     // -XX:Foo:=xxx will reset the string flag to the given value.
 713     if (value[0] == '\0') {
 714       value = NULL;
 715     }
 716     return set_string_flag(name, value, origin);
 717   }
 718 
 719 #define SIGNED_FP_NUMBER_RANGE "[-0123456789.]"
 720 #define SIGNED_NUMBER_RANGE    "[-0123456789]"
 721 #define        NUMBER_RANGE    "[0123456789]"
 722   char value[BUFLEN + 1];
 723   char value2[BUFLEN + 1];
 724   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_NUMBER_RANGE "." "%" XSTR(BUFLEN) NUMBER_RANGE "%c", name, value, value2, &dummy) == 3) {
 725     // Looks like a floating-point number -- try again with more lenient format string
 726     if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_FP_NUMBER_RANGE "%c", name, value, &dummy) == 2) {
 727       return set_fp_numeric_flag(name, value, origin);
 728     }
 729   }
 730 
 731 #define VALUE_RANGE "[-kmgtKMGT0123456789]"
 732   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) VALUE_RANGE "%c", name, value, &dummy) == 2) {
 733     return set_numeric_flag(name, value, origin);
 734   }
 735 
 736   return false;
 737 }
 738 
 739 void Arguments::add_string(char*** bldarray, int* count, const char* arg) {
 740   assert(bldarray != NULL, "illegal argument");
 741 
 742   if (arg == NULL) {
 743     return;
 744   }
 745 
 746   int index = *count;
 747 
 748   // expand the array and add arg to the last element
 749   (*count)++;
 750   if (*bldarray == NULL) {
 751     *bldarray = NEW_C_HEAP_ARRAY(char*, *count, mtInternal);
 752   } else {
 753     *bldarray = REALLOC_C_HEAP_ARRAY(char*, *bldarray, *count, mtInternal);
 754   }
 755   (*bldarray)[index] = strdup(arg);
 756 }
 757 
 758 void Arguments::build_jvm_args(const char* arg) {
 759   add_string(&_jvm_args_array, &_num_jvm_args, arg);
 760 }
 761 
 762 void Arguments::build_jvm_flags(const char* arg) {
 763   add_string(&_jvm_flags_array, &_num_jvm_flags, arg);
 764 }
 765 
 766 // utility function to return a string that concatenates all
 767 // strings in a given char** array
 768 const char* Arguments::build_resource_string(char** args, int count) {
 769   if (args == NULL || count == 0) {
 770     return NULL;
 771   }
 772   size_t length = strlen(args[0]) + 1; // add 1 for the null terminator
 773   for (int i = 1; i < count; i++) {
 774     length += strlen(args[i]) + 1; // add 1 for a space
 775   }
 776   char* s = NEW_RESOURCE_ARRAY(char, length);
 777   strcpy(s, args[0]);
 778   for (int j = 1; j < count; j++) {
 779     strcat(s, " ");
 780     strcat(s, args[j]);
 781   }
 782   return (const char*) s;
 783 }
 784 
 785 void Arguments::print_on(outputStream* st) {
 786   st->print_cr("VM Arguments:");
 787   if (num_jvm_flags() > 0) {
 788     st->print("jvm_flags: "); print_jvm_flags_on(st);
 789   }
 790   if (num_jvm_args() > 0) {
 791     st->print("jvm_args: "); print_jvm_args_on(st);
 792   }
 793   st->print_cr("java_command: %s", java_command() ? java_command() : "<unknown>");
 794   st->print_cr("Launcher Type: %s", _sun_java_launcher);
 795 }
 796 
 797 void Arguments::print_jvm_flags_on(outputStream* st) {
 798   if (_num_jvm_flags > 0) {
 799     for (int i=0; i < _num_jvm_flags; i++) {
 800       st->print("%s ", _jvm_flags_array[i]);
 801     }
 802     st->print_cr("");
 803   }
 804 }
 805 
 806 void Arguments::print_jvm_args_on(outputStream* st) {
 807   if (_num_jvm_args > 0) {
 808     for (int i=0; i < _num_jvm_args; i++) {
 809       st->print("%s ", _jvm_args_array[i]);
 810     }
 811     st->print_cr("");
 812   }
 813 }
 814 
 815 bool Arguments::process_argument(const char* arg,
 816     jboolean ignore_unrecognized, FlagValueOrigin origin) {
 817 
 818   JDK_Version since = JDK_Version();
 819 
 820   if (parse_argument(arg, origin) || ignore_unrecognized) {
 821     return true;
 822   }
 823 
 824   const char * const argname = *arg == '+' || *arg == '-' ? arg + 1 : arg;
 825   if (is_newly_obsolete(arg, &since)) {
 826     char version[256];
 827     since.to_string(version, sizeof(version));
 828     warning("ignoring option %s; support was removed in %s", argname, version);
 829     return true;
 830   }
 831 
 832   // For locked flags, report a custom error message if available.
 833   // Otherwise, report the standard unrecognized VM option.
 834 
 835   Flag* locked_flag = Flag::find_flag((char*)argname, strlen(argname), true);
 836   if (locked_flag != NULL) {
 837     char locked_message_buf[BUFLEN];
 838     locked_flag->get_locked_message(locked_message_buf, BUFLEN);
 839     if (strlen(locked_message_buf) == 0) {
 840       jio_fprintf(defaultStream::error_stream(),
 841         "Unrecognized VM option '%s'\n", argname);
 842     } else {
 843       jio_fprintf(defaultStream::error_stream(), "%s", locked_message_buf);
 844     }
 845   } else {
 846     jio_fprintf(defaultStream::error_stream(),
 847                 "Unrecognized VM option '%s'\n", argname);
 848   }
 849 
 850   // allow for commandline "commenting out" options like -XX:#+Verbose
 851   return arg[0] == '#';
 852 }
 853 
 854 bool Arguments::process_settings_file(const char* file_name, bool should_exist, jboolean ignore_unrecognized) {
 855   FILE* stream = fopen(file_name, "rb");
 856   if (stream == NULL) {
 857     if (should_exist) {
 858       jio_fprintf(defaultStream::error_stream(),
 859                   "Could not open settings file %s\n", file_name);
 860       return false;
 861     } else {
 862       return true;
 863     }
 864   }
 865 
 866   char token[1024];
 867   int  pos = 0;
 868 
 869   bool in_white_space = true;
 870   bool in_comment     = false;
 871   bool in_quote       = false;
 872   char quote_c        = 0;
 873   bool result         = true;
 874 
 875   int c = getc(stream);
 876   while(c != EOF) {
 877     if (in_white_space) {
 878       if (in_comment) {
 879         if (c == '\n') in_comment = false;
 880       } else {
 881         if (c == '#') in_comment = true;
 882         else if (!isspace(c)) {
 883           in_white_space = false;
 884           token[pos++] = c;
 885         }
 886       }
 887     } else {
 888       if (c == '\n' || (!in_quote && isspace(c))) {
 889         // token ends at newline, or at unquoted whitespace
 890         // this allows a way to include spaces in string-valued options
 891         token[pos] = '\0';
 892         logOption(token);
 893         result &= process_argument(token, ignore_unrecognized, CONFIG_FILE);
 894         build_jvm_flags(token);
 895         pos = 0;
 896         in_white_space = true;
 897         in_quote = false;
 898       } else if (!in_quote && (c == '\'' || c == '"')) {
 899         in_quote = true;
 900         quote_c = c;
 901       } else if (in_quote && (c == quote_c)) {
 902         in_quote = false;
 903       } else {
 904         token[pos++] = c;
 905       }
 906     }
 907     c = getc(stream);
 908   }
 909   if (pos > 0) {
 910     token[pos] = '\0';
 911     result &= process_argument(token, ignore_unrecognized, CONFIG_FILE);
 912     build_jvm_flags(token);
 913   }
 914   fclose(stream);
 915   return result;
 916 }
 917 
 918 //=============================================================================================================
 919 // Parsing of properties (-D)
 920 
 921 const char* Arguments::get_property(const char* key) {
 922   return PropertyList_get_value(system_properties(), key);
 923 }
 924 
 925 bool Arguments::add_property(const char* prop) {
 926   const char* eq = strchr(prop, '=');
 927   char* key;
 928   // ns must be static--its address may be stored in a SystemProperty object.
 929   const static char ns[1] = {0};
 930   char* value = (char *)ns;
 931 
 932   size_t key_len = (eq == NULL) ? strlen(prop) : (eq - prop);
 933   key = AllocateHeap(key_len + 1, mtInternal);
 934   strncpy(key, prop, key_len);
 935   key[key_len] = '\0';
 936 
 937   if (eq != NULL) {
 938     size_t value_len = strlen(prop) - key_len - 1;
 939     value = AllocateHeap(value_len + 1, mtInternal);
 940     strncpy(value, &prop[key_len + 1], value_len + 1);
 941   }
 942 
 943   if (strcmp(key, "java.compiler") == 0) {
 944     process_java_compiler_argument(value);
 945     FreeHeap(key);
 946     if (eq != NULL) {
 947       FreeHeap(value);
 948     }
 949     return true;
 950   } else if (strcmp(key, "sun.java.command") == 0) {
 951     _java_command = value;
 952 
 953     // Record value in Arguments, but let it get passed to Java.
 954   } else if (strcmp(key, "sun.java.launcher.pid") == 0) {
 955     // launcher.pid property is private and is processed
 956     // in process_sun_java_launcher_properties();
 957     // the sun.java.launcher property is passed on to the java application
 958     FreeHeap(key);
 959     if (eq != NULL) {
 960       FreeHeap(value);
 961     }
 962     return true;
 963   } else if (strcmp(key, "java.vendor.url.bug") == 0) {
 964     // save it in _java_vendor_url_bug, so JVM fatal error handler can access
 965     // its value without going through the property list or making a Java call.
 966     _java_vendor_url_bug = value;
 967   } else if (strcmp(key, "sun.boot.library.path") == 0) {
 968     PropertyList_unique_add(&_system_properties, key, value, true);
 969     return true;
 970   }
 971   // Create new property and add at the end of the list
 972   PropertyList_unique_add(&_system_properties, key, value);
 973   return true;
 974 }
 975 
 976 //===========================================================================================================
 977 // Setting int/mixed/comp mode flags
 978 
 979 void Arguments::set_mode_flags(Mode mode) {
 980   // Set up default values for all flags.
 981   // If you add a flag to any of the branches below,
 982   // add a default value for it here.
 983   set_java_compiler(false);
 984   _mode                      = mode;
 985 
 986   // Ensure Agent_OnLoad has the correct initial values.
 987   // This may not be the final mode; mode may change later in onload phase.
 988   PropertyList_unique_add(&_system_properties, "java.vm.info",
 989                           (char*)VM_Version::vm_info_string(), false);
 990 
 991   UseInterpreter             = true;
 992   UseCompiler                = true;
 993   UseLoopCounter             = true;
 994 
 995 #ifndef ZERO
 996   // Turn these off for mixed and comp.  Leave them on for Zero.
 997   if (FLAG_IS_DEFAULT(UseFastAccessorMethods)) {
 998     UseFastAccessorMethods = (mode == _int);
 999   }
1000   if (FLAG_IS_DEFAULT(UseFastEmptyMethods)) {
1001     UseFastEmptyMethods = (mode == _int);
1002   }
1003 #endif
1004 
1005   // Default values may be platform/compiler dependent -
1006   // use the saved values
1007   ClipInlining               = Arguments::_ClipInlining;
1008   AlwaysCompileLoopMethods   = Arguments::_AlwaysCompileLoopMethods;
1009   UseOnStackReplacement      = Arguments::_UseOnStackReplacement;
1010   BackgroundCompilation      = Arguments::_BackgroundCompilation;
1011 
1012   // Change from defaults based on mode
1013   switch (mode) {
1014   default:
1015     ShouldNotReachHere();
1016     break;
1017   case _int:
1018     UseCompiler              = false;
1019     UseLoopCounter           = false;
1020     AlwaysCompileLoopMethods = false;
1021     UseOnStackReplacement    = false;
1022     break;
1023   case _mixed:
1024     // same as default
1025     break;
1026   case _comp:
1027     UseInterpreter           = false;
1028     BackgroundCompilation    = false;
1029     ClipInlining             = false;
1030     // Be much more aggressive in tiered mode with -Xcomp and exercise C2 more.
1031     // We will first compile a level 3 version (C1 with full profiling), then do one invocation of it and
1032     // compile a level 4 (C2) and then continue executing it.
1033     if (TieredCompilation) {
1034       Tier3InvokeNotifyFreqLog = 0;
1035       Tier4InvocationThreshold = 0;
1036     }
1037     break;
1038   }
1039 }
1040 
1041 // Conflict: required to use shared spaces (-Xshare:on), but
1042 // incompatible command line options were chosen.
1043 
1044 static void no_shared_spaces() {
1045   if (RequireSharedSpaces) {
1046     jio_fprintf(defaultStream::error_stream(),
1047       "Class data sharing is inconsistent with other specified options.\n");
1048     vm_exit_during_initialization("Unable to use shared archive.", NULL);
1049   } else {
1050     FLAG_SET_DEFAULT(UseSharedSpaces, false);
1051   }
1052 }
1053 
1054 void Arguments::set_tiered_flags() {
1055   // With tiered, set default policy to AdvancedThresholdPolicy, which is 3.
1056   if (FLAG_IS_DEFAULT(CompilationPolicyChoice)) {
1057     FLAG_SET_DEFAULT(CompilationPolicyChoice, 3);
1058   }
1059   if (CompilationPolicyChoice < 2) {
1060     vm_exit_during_initialization(
1061       "Incompatible compilation policy selected", NULL);
1062   }
1063   // Increase the code cache size - tiered compiles a lot more.
1064   if (FLAG_IS_DEFAULT(ReservedCodeCacheSize)) {
1065     FLAG_SET_DEFAULT(ReservedCodeCacheSize, ReservedCodeCacheSize * 2);
1066   }
1067 }
1068 
1069 #ifndef KERNEL
1070 static void disable_adaptive_size_policy(const char* collector_name) {
1071   if (UseAdaptiveSizePolicy) {
1072     if (FLAG_IS_CMDLINE(UseAdaptiveSizePolicy)) {
1073       warning("disabling UseAdaptiveSizePolicy; it is incompatible with %s.",
1074               collector_name);
1075     }
1076     FLAG_SET_DEFAULT(UseAdaptiveSizePolicy, false);
1077   }
1078 }
1079 
1080 // If the user has chosen ParallelGCThreads > 0, we set UseParNewGC
1081 // if it's not explictly set or unset. If the user has chosen
1082 // UseParNewGC and not explicitly set ParallelGCThreads we
1083 // set it, unless this is a single cpu machine.
1084 void Arguments::set_parnew_gc_flags() {
1085   assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC && !UseG1GC,
1086          "control point invariant");
1087   assert(UseParNewGC, "Error");
1088 
1089   // Turn off AdaptiveSizePolicy for parnew until it is complete.
1090   disable_adaptive_size_policy("UseParNewGC");
1091 
1092   if (ParallelGCThreads == 0) {
1093     FLAG_SET_DEFAULT(ParallelGCThreads,
1094                      Abstract_VM_Version::parallel_worker_threads());
1095     if (ParallelGCThreads == 1) {
1096       FLAG_SET_DEFAULT(UseParNewGC, false);
1097       FLAG_SET_DEFAULT(ParallelGCThreads, 0);
1098     }
1099   }
1100   if (UseParNewGC) {
1101     // By default YoungPLABSize and OldPLABSize are set to 4096 and 1024 respectively,
1102     // these settings are default for Parallel Scavenger. For ParNew+Tenured configuration
1103     // we set them to 1024 and 1024.
1104     // See CR 6362902.
1105     if (FLAG_IS_DEFAULT(YoungPLABSize)) {
1106       FLAG_SET_DEFAULT(YoungPLABSize, (intx)1024);
1107     }
1108     if (FLAG_IS_DEFAULT(OldPLABSize)) {
1109       FLAG_SET_DEFAULT(OldPLABSize, (intx)1024);
1110     }
1111 
1112     // AlwaysTenure flag should make ParNew promote all at first collection.
1113     // See CR 6362902.
1114     if (AlwaysTenure) {
1115       FLAG_SET_CMDLINE(intx, MaxTenuringThreshold, 0);
1116     }
1117     // When using compressed oops, we use local overflow stacks,
1118     // rather than using a global overflow list chained through
1119     // the klass word of the object's pre-image.
1120     if (UseCompressedOops && !ParGCUseLocalOverflow) {
1121       if (!FLAG_IS_DEFAULT(ParGCUseLocalOverflow)) {
1122         warning("Forcing +ParGCUseLocalOverflow: needed if using compressed references");
1123       }
1124       FLAG_SET_DEFAULT(ParGCUseLocalOverflow, true);
1125     }
1126     assert(ParGCUseLocalOverflow || !UseCompressedOops, "Error");
1127   }
1128 }
1129 
1130 // Adjust some sizes to suit CMS and/or ParNew needs; these work well on
1131 // sparc/solaris for certain applications, but would gain from
1132 // further optimization and tuning efforts, and would almost
1133 // certainly gain from analysis of platform and environment.
1134 void Arguments::set_cms_and_parnew_gc_flags() {
1135   assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC, "Error");
1136   assert(UseConcMarkSweepGC, "CMS is expected to be on here");
1137 
1138   // If we are using CMS, we prefer to UseParNewGC,
1139   // unless explicitly forbidden.
1140   if (FLAG_IS_DEFAULT(UseParNewGC)) {
1141     FLAG_SET_ERGO(bool, UseParNewGC, true);
1142   }
1143 
1144   // Turn off AdaptiveSizePolicy for CMS until it is complete.
1145   disable_adaptive_size_policy("UseConcMarkSweepGC");
1146 
1147   // In either case, adjust ParallelGCThreads and/or UseParNewGC
1148   // as needed.
1149   if (UseParNewGC) {
1150     set_parnew_gc_flags();
1151   }
1152 
1153   // MaxHeapSize is aligned down in collectorPolicy
1154   size_t max_heap = align_size_down(MaxHeapSize,
1155                                     CardTableRS::ct_max_alignment_constraint());
1156 
1157   // Now make adjustments for CMS
1158   intx   tenuring_default = (intx)6;
1159   size_t young_gen_per_worker = CMSYoungGenPerWorker;
1160 
1161   // Preferred young gen size for "short" pauses:
1162   // upper bound depends on # of threads and NewRatio.
1163   const uintx parallel_gc_threads =
1164     (ParallelGCThreads == 0 ? 1 : ParallelGCThreads);
1165   const size_t preferred_max_new_size_unaligned =
1166     MIN2(max_heap/(NewRatio+1), ScaleForWordSize(young_gen_per_worker * parallel_gc_threads));
1167   size_t preferred_max_new_size =
1168     align_size_up(preferred_max_new_size_unaligned, os::vm_page_size());
1169 
1170   // Unless explicitly requested otherwise, size young gen
1171   // for "short" pauses ~ CMSYoungGenPerWorker*ParallelGCThreads
1172 
1173   // If either MaxNewSize or NewRatio is set on the command line,
1174   // assume the user is trying to set the size of the young gen.
1175   if (FLAG_IS_DEFAULT(MaxNewSize) && FLAG_IS_DEFAULT(NewRatio)) {
1176 
1177     // Set MaxNewSize to our calculated preferred_max_new_size unless
1178     // NewSize was set on the command line and it is larger than
1179     // preferred_max_new_size.
1180     if (!FLAG_IS_DEFAULT(NewSize)) {   // NewSize explicitly set at command-line
1181       FLAG_SET_ERGO(uintx, MaxNewSize, MAX2(NewSize, preferred_max_new_size));
1182     } else {
1183       FLAG_SET_ERGO(uintx, MaxNewSize, preferred_max_new_size);
1184     }
1185     if (PrintGCDetails && Verbose) {
1186       // Too early to use gclog_or_tty
1187       tty->print_cr("CMS ergo set MaxNewSize: " SIZE_FORMAT, MaxNewSize);
1188     }
1189 
1190     // Code along this path potentially sets NewSize and OldSize
1191 
1192     assert(max_heap >= InitialHeapSize, "Error");
1193     assert(max_heap >= NewSize, "Error");
1194 
1195     if (PrintGCDetails && Verbose) {
1196       // Too early to use gclog_or_tty
1197       tty->print_cr("CMS set min_heap_size: " SIZE_FORMAT
1198            " initial_heap_size:  " SIZE_FORMAT
1199            " max_heap: " SIZE_FORMAT,
1200            min_heap_size(), InitialHeapSize, max_heap);
1201     }
1202     size_t min_new = preferred_max_new_size;
1203     if (FLAG_IS_CMDLINE(NewSize)) {
1204       min_new = NewSize;
1205     }
1206     if (max_heap > min_new && min_heap_size() > min_new) {
1207       // Unless explicitly requested otherwise, make young gen
1208       // at least min_new, and at most preferred_max_new_size.
1209       if (FLAG_IS_DEFAULT(NewSize)) {
1210         FLAG_SET_ERGO(uintx, NewSize, MAX2(NewSize, min_new));
1211         FLAG_SET_ERGO(uintx, NewSize, MIN2(preferred_max_new_size, NewSize));
1212         if (PrintGCDetails && Verbose) {
1213           // Too early to use gclog_or_tty
1214           tty->print_cr("CMS ergo set NewSize: " SIZE_FORMAT, NewSize);
1215         }
1216       }
1217       // Unless explicitly requested otherwise, size old gen
1218       // so it's NewRatio x of NewSize.
1219       if (FLAG_IS_DEFAULT(OldSize)) {
1220         if (max_heap > NewSize) {
1221           FLAG_SET_ERGO(uintx, OldSize, MIN2(NewRatio*NewSize, max_heap - NewSize));
1222           if (PrintGCDetails && Verbose) {
1223             // Too early to use gclog_or_tty
1224             tty->print_cr("CMS ergo set OldSize: " SIZE_FORMAT, OldSize);
1225           }
1226         }
1227       }
1228     }
1229   }
1230   // Unless explicitly requested otherwise, definitely
1231   // promote all objects surviving "tenuring_default" scavenges.
1232   if (FLAG_IS_DEFAULT(MaxTenuringThreshold) &&
1233       FLAG_IS_DEFAULT(SurvivorRatio)) {
1234     FLAG_SET_ERGO(intx, MaxTenuringThreshold, tenuring_default);
1235   }
1236   // If we decided above (or user explicitly requested)
1237   // `promote all' (via MaxTenuringThreshold := 0),
1238   // prefer minuscule survivor spaces so as not to waste
1239   // space for (non-existent) survivors
1240   if (FLAG_IS_DEFAULT(SurvivorRatio) && MaxTenuringThreshold == 0) {
1241     FLAG_SET_ERGO(intx, SurvivorRatio, MAX2((intx)1024, SurvivorRatio));
1242   }
1243   // If OldPLABSize is set and CMSParPromoteBlocksToClaim is not,
1244   // set CMSParPromoteBlocksToClaim equal to OldPLABSize.
1245   // This is done in order to make ParNew+CMS configuration to work
1246   // with YoungPLABSize and OldPLABSize options.
1247   // See CR 6362902.
1248   if (!FLAG_IS_DEFAULT(OldPLABSize)) {
1249     if (FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim)) {
1250       // OldPLABSize is not the default value but CMSParPromoteBlocksToClaim
1251       // is.  In this situtation let CMSParPromoteBlocksToClaim follow
1252       // the value (either from the command line or ergonomics) of
1253       // OldPLABSize.  Following OldPLABSize is an ergonomics decision.
1254       FLAG_SET_ERGO(uintx, CMSParPromoteBlocksToClaim, OldPLABSize);
1255     } else {
1256       // OldPLABSize and CMSParPromoteBlocksToClaim are both set.
1257       // CMSParPromoteBlocksToClaim is a collector-specific flag, so
1258       // we'll let it to take precedence.
1259       jio_fprintf(defaultStream::error_stream(),
1260                   "Both OldPLABSize and CMSParPromoteBlocksToClaim"
1261                   " options are specified for the CMS collector."
1262                   " CMSParPromoteBlocksToClaim will take precedence.\n");
1263     }
1264   }
1265   if (!FLAG_IS_DEFAULT(ResizeOldPLAB) && !ResizeOldPLAB) {
1266     // OldPLAB sizing manually turned off: Use a larger default setting,
1267     // unless it was manually specified. This is because a too-low value
1268     // will slow down scavenges.
1269     if (FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim)) {
1270       FLAG_SET_ERGO(uintx, CMSParPromoteBlocksToClaim, 50); // default value before 6631166
1271     }
1272   }
1273   // Overwrite OldPLABSize which is the variable we will internally use everywhere.
1274   FLAG_SET_ERGO(uintx, OldPLABSize, CMSParPromoteBlocksToClaim);
1275   // If either of the static initialization defaults have changed, note this
1276   // modification.
1277   if (!FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim) || !FLAG_IS_DEFAULT(OldPLABWeight)) {
1278     CFLS_LAB::modify_initialization(OldPLABSize, OldPLABWeight);
1279   }
1280   if (PrintGCDetails && Verbose) {
1281     tty->print_cr("MarkStackSize: %uk  MarkStackSizeMax: %uk",
1282       MarkStackSize / K, MarkStackSizeMax / K);
1283     tty->print_cr("ConcGCThreads: %u", ConcGCThreads);
1284   }
1285 }
1286 #endif // KERNEL
1287 
1288 void set_object_alignment() {
1289   // Object alignment.
1290   assert(is_power_of_2(ObjectAlignmentInBytes), "ObjectAlignmentInBytes must be power of 2");
1291   MinObjAlignmentInBytes     = ObjectAlignmentInBytes;
1292   assert(MinObjAlignmentInBytes >= HeapWordsPerLong * HeapWordSize, "ObjectAlignmentInBytes value is too small");
1293   MinObjAlignment            = MinObjAlignmentInBytes / HeapWordSize;
1294   assert(MinObjAlignmentInBytes == MinObjAlignment * HeapWordSize, "ObjectAlignmentInBytes value is incorrect");
1295   MinObjAlignmentInBytesMask = MinObjAlignmentInBytes - 1;
1296 
1297   LogMinObjAlignmentInBytes  = exact_log2(ObjectAlignmentInBytes);
1298   LogMinObjAlignment         = LogMinObjAlignmentInBytes - LogHeapWordSize;
1299 
1300   // Oop encoding heap max
1301   OopEncodingHeapMax = (uint64_t(max_juint) + 1) << LogMinObjAlignmentInBytes;
1302 
1303 #ifndef KERNEL
1304   // Set CMS global values
1305   CompactibleFreeListSpace::set_cms_values();
1306 #endif // KERNEL
1307 }
1308 
1309 bool verify_object_alignment() {
1310   // Object alignment.
1311   if (!is_power_of_2(ObjectAlignmentInBytes)) {
1312     jio_fprintf(defaultStream::error_stream(),
1313                 "error: ObjectAlignmentInBytes=%d must be power of 2\n",
1314                 (int)ObjectAlignmentInBytes);
1315     return false;
1316   }
1317   if ((int)ObjectAlignmentInBytes < BytesPerLong) {
1318     jio_fprintf(defaultStream::error_stream(),
1319                 "error: ObjectAlignmentInBytes=%d must be greater or equal %d\n",
1320                 (int)ObjectAlignmentInBytes, BytesPerLong);
1321     return false;
1322   }
1323   // It does not make sense to have big object alignment
1324   // since a space lost due to alignment will be greater
1325   // then a saved space from compressed oops.
1326   if ((int)ObjectAlignmentInBytes > 256) {
1327     jio_fprintf(defaultStream::error_stream(),
1328                 "error: ObjectAlignmentInBytes=%d must not be greater then 256\n",
1329                 (int)ObjectAlignmentInBytes);
1330     return false;
1331   }
1332   // In case page size is very small.
1333   if ((int)ObjectAlignmentInBytes >= os::vm_page_size()) {
1334     jio_fprintf(defaultStream::error_stream(),
1335                 "error: ObjectAlignmentInBytes=%d must be less then page size %d\n",
1336                 (int)ObjectAlignmentInBytes, os::vm_page_size());
1337     return false;
1338   }
1339   return true;
1340 }
1341 
1342 inline uintx max_heap_for_compressed_oops() {
1343   // Avoid sign flip.
1344   if (OopEncodingHeapMax < ClassMetaspaceSize + os::vm_page_size()) {
1345     return 0;
1346   }
1347   LP64_ONLY(return OopEncodingHeapMax - ClassMetaspaceSize - os::vm_page_size());
1348   NOT_LP64(ShouldNotReachHere(); return 0);
1349 }
1350 
1351 bool Arguments::should_auto_select_low_pause_collector() {
1352   if (UseAutoGCSelectPolicy &&
1353       !FLAG_IS_DEFAULT(MaxGCPauseMillis) &&
1354       (MaxGCPauseMillis <= AutoGCSelectPauseMillis)) {
1355     if (PrintGCDetails) {
1356       // Cannot use gclog_or_tty yet.
1357       tty->print_cr("Automatic selection of the low pause collector"
1358        " based on pause goal of %d (ms)", MaxGCPauseMillis);
1359     }
1360     return true;
1361   }
1362   return false;
1363 }
1364 
1365 void Arguments::set_ergonomics_flags() {
1366 
1367   if (os::is_server_class_machine()) {
1368     // If no other collector is requested explicitly,
1369     // let the VM select the collector based on
1370     // machine class and automatic selection policy.
1371     if (!UseSerialGC &&
1372         !UseConcMarkSweepGC &&
1373         !UseG1GC &&
1374         !UseParNewGC &&
1375         FLAG_IS_DEFAULT(UseParallelGC)) {
1376       if (should_auto_select_low_pause_collector()) {
1377         FLAG_SET_ERGO(bool, UseConcMarkSweepGC, true);
1378       } else {
1379         FLAG_SET_ERGO(bool, UseParallelGC, true);
1380       }
1381     }
1382     // Shared spaces work fine with other GCs but causes bytecode rewriting
1383     // to be disabled, which hurts interpreter performance and decreases
1384     // server performance.   On server class machines, keep the default
1385     // off unless it is asked for.  Future work: either add bytecode rewriting
1386     // at link time, or rewrite bytecodes in non-shared methods.
1387     if (!DumpSharedSpaces && !RequireSharedSpaces) {
1388       no_shared_spaces();
1389     }
1390   }
1391 
1392 #ifndef ZERO
1393 #ifdef _LP64
1394   // Check that UseCompressedOops can be set with the max heap size allocated
1395   // by ergonomics.
1396   if (MaxHeapSize <= max_heap_for_compressed_oops()) {
1397 #if !defined(COMPILER1) || defined(TIERED)
1398     if (FLAG_IS_DEFAULT(UseCompressedOops)) {
1399       FLAG_SET_ERGO(bool, UseCompressedOops, true);
1400     }
1401 #endif
1402 #ifdef _WIN64
1403     if (UseLargePages && UseCompressedOops) {
1404       // Cannot allocate guard pages for implicit checks in indexed addressing
1405       // mode, when large pages are specified on windows.
1406       // This flag could be switched ON if narrow oop base address is set to 0,
1407       // see code in Universe::initialize_heap().
1408       Universe::set_narrow_oop_use_implicit_null_checks(false);
1409     }
1410 #endif //  _WIN64
1411   } else {
1412     if (UseCompressedOops && !FLAG_IS_DEFAULT(UseCompressedOops)) {
1413       warning("Max heap size too large for Compressed Oops");
1414       FLAG_SET_DEFAULT(UseCompressedOops, false);
1415       FLAG_SET_DEFAULT(UseCompressedKlassPointers, false);
1416     }
1417   }
1418   // UseCompressedOops must be on for UseCompressedKlassPointers to be on.
1419   if (!UseCompressedOops) {
1420     if (UseCompressedKlassPointers) {
1421       warning("UseCompressedKlassPointers requires UseCompressedOops");
1422     }
1423     FLAG_SET_DEFAULT(UseCompressedKlassPointers, false);
1424   } else {
1425     // Turn on UseCompressedKlassPointers too
1426     // The compiler is broken for this so turn it on when the compiler is fixed.
1427     // if (FLAG_IS_DEFAULT(UseCompressedKlassPointers)) {
1428     //   FLAG_SET_ERGO(bool, UseCompressedKlassPointers, true);
1429     // }
1430     // Set the ClassMetaspaceSize to something that will not need to be
1431     // expanded, since it cannot be expanded.
1432     if (UseCompressedKlassPointers && FLAG_IS_DEFAULT(ClassMetaspaceSize)) {
1433       // 100,000 classes seems like a good size, so 100M assumes around 1K
1434       // per klass.   The vtable and oopMap is embedded so we don't have a fixed
1435       // size per klass.   Eventually, this will be parameterized because it
1436       // would also be useful to determine the optimal size of the
1437       // systemDictionary.
1438       FLAG_SET_ERGO(uintx, ClassMetaspaceSize, 100*M);
1439     }
1440   }
1441   // Also checks that certain machines are slower with compressed oops
1442   // in vm_version initialization code.
1443 #endif // _LP64
1444 #endif // !ZERO
1445 }
1446 
1447 void Arguments::set_parallel_gc_flags() {
1448   assert(UseParallelGC || UseParallelOldGC, "Error");
1449   // Enable ParallelOld unless it was explicitly disabled (cmd line or rc file).
1450   if (FLAG_IS_DEFAULT(UseParallelOldGC)) {
1451     FLAG_SET_DEFAULT(UseParallelOldGC, true);
1452   }
1453   FLAG_SET_DEFAULT(UseParallelGC, true);
1454 
1455   // If no heap maximum was requested explicitly, use some reasonable fraction
1456   // of the physical memory, up to a maximum of 1GB.
1457   if (UseParallelGC) {
1458     FLAG_SET_DEFAULT(ParallelGCThreads,
1459                      Abstract_VM_Version::parallel_worker_threads());
1460 
1461     // If InitialSurvivorRatio or MinSurvivorRatio were not specified, but the
1462     // SurvivorRatio has been set, reset their default values to SurvivorRatio +
1463     // 2.  By doing this we make SurvivorRatio also work for Parallel Scavenger.
1464     // See CR 6362902 for details.
1465     if (!FLAG_IS_DEFAULT(SurvivorRatio)) {
1466       if (FLAG_IS_DEFAULT(InitialSurvivorRatio)) {
1467          FLAG_SET_DEFAULT(InitialSurvivorRatio, SurvivorRatio + 2);
1468       }
1469       if (FLAG_IS_DEFAULT(MinSurvivorRatio)) {
1470         FLAG_SET_DEFAULT(MinSurvivorRatio, SurvivorRatio + 2);
1471       }
1472     }
1473 
1474     if (UseParallelOldGC) {
1475       // Par compact uses lower default values since they are treated as
1476       // minimums.  These are different defaults because of the different
1477       // interpretation and are not ergonomically set.
1478       if (FLAG_IS_DEFAULT(MarkSweepDeadRatio)) {
1479         FLAG_SET_DEFAULT(MarkSweepDeadRatio, 1);
1480       }
1481     }
1482   }
1483   if (UseNUMA) {
1484     if (FLAG_IS_DEFAULT(MinHeapDeltaBytes)) {
1485       FLAG_SET_DEFAULT(MinHeapDeltaBytes, 64*M);
1486     }
1487     // For those collectors or operating systems (eg, Windows) that do
1488     // not support full UseNUMA, we will map to UseNUMAInterleaving for now
1489     UseNUMAInterleaving = true;
1490   }
1491 }
1492 
1493 void Arguments::set_g1_gc_flags() {
1494   assert(UseG1GC, "Error");
1495 #ifdef COMPILER1
1496   FastTLABRefill = false;
1497 #endif
1498   FLAG_SET_DEFAULT(ParallelGCThreads,
1499                      Abstract_VM_Version::parallel_worker_threads());
1500   if (ParallelGCThreads == 0) {
1501     FLAG_SET_DEFAULT(ParallelGCThreads,
1502                      Abstract_VM_Version::parallel_worker_threads());
1503   }
1504 
1505   if (FLAG_IS_DEFAULT(MarkStackSize)) {
1506     FLAG_SET_DEFAULT(MarkStackSize, 128 * TASKQUEUE_SIZE);
1507   }
1508   if (PrintGCDetails && Verbose) {
1509     tty->print_cr("MarkStackSize: %uk  MarkStackSizeMax: %uk",
1510       MarkStackSize / K, MarkStackSizeMax / K);
1511     tty->print_cr("ConcGCThreads: %u", ConcGCThreads);
1512   }
1513 
1514   if (FLAG_IS_DEFAULT(GCTimeRatio) || GCTimeRatio == 0) {
1515     // In G1, we want the default GC overhead goal to be higher than
1516     // say in PS. So we set it here to 10%. Otherwise the heap might
1517     // be expanded more aggressively than we would like it to. In
1518     // fact, even 10% seems to not be high enough in some cases
1519     // (especially small GC stress tests that the main thing they do
1520     // is allocation). We might consider increase it further.
1521     FLAG_SET_DEFAULT(GCTimeRatio, 9);
1522   }
1523 }
1524 
1525 void Arguments::set_heap_size() {
1526   if (!FLAG_IS_DEFAULT(DefaultMaxRAMFraction)) {
1527     // Deprecated flag
1528     FLAG_SET_CMDLINE(uintx, MaxRAMFraction, DefaultMaxRAMFraction);
1529   }
1530 
1531   const julong phys_mem =
1532     FLAG_IS_DEFAULT(MaxRAM) ? MIN2(os::physical_memory(), (julong)MaxRAM)
1533                             : (julong)MaxRAM;
1534 
1535   // If the maximum heap size has not been set with -Xmx,
1536   // then set it as fraction of the size of physical memory,
1537   // respecting the maximum and minimum sizes of the heap.
1538   if (FLAG_IS_DEFAULT(MaxHeapSize)) {
1539     julong reasonable_max = phys_mem / MaxRAMFraction;
1540 
1541     if (phys_mem <= MaxHeapSize * MinRAMFraction) {
1542       // Small physical memory, so use a minimum fraction of it for the heap
1543       reasonable_max = phys_mem / MinRAMFraction;
1544     } else {
1545       // Not-small physical memory, so require a heap at least
1546       // as large as MaxHeapSize
1547       reasonable_max = MAX2(reasonable_max, (julong)MaxHeapSize);
1548     }
1549     if (!FLAG_IS_DEFAULT(ErgoHeapSizeLimit) && ErgoHeapSizeLimit != 0) {
1550       // Limit the heap size to ErgoHeapSizeLimit
1551       reasonable_max = MIN2(reasonable_max, (julong)ErgoHeapSizeLimit);
1552     }
1553     if (UseCompressedOops) {
1554       // Limit the heap size to the maximum possible when using compressed oops
1555       julong max_coop_heap = (julong)max_heap_for_compressed_oops();
1556       if (HeapBaseMinAddress + MaxHeapSize < max_coop_heap) {
1557         // Heap should be above HeapBaseMinAddress to get zero based compressed oops
1558         // but it should be not less than default MaxHeapSize.
1559         max_coop_heap -= HeapBaseMinAddress;
1560       }
1561       reasonable_max = MIN2(reasonable_max, max_coop_heap);
1562     }
1563     reasonable_max = os::allocatable_physical_memory(reasonable_max);
1564 
1565     if (!FLAG_IS_DEFAULT(InitialHeapSize)) {
1566       // An initial heap size was specified on the command line,
1567       // so be sure that the maximum size is consistent.  Done
1568       // after call to allocatable_physical_memory because that
1569       // method might reduce the allocation size.
1570       reasonable_max = MAX2(reasonable_max, (julong)InitialHeapSize);
1571     }
1572 
1573     if (PrintGCDetails && Verbose) {
1574       // Cannot use gclog_or_tty yet.
1575       tty->print_cr("  Maximum heap size " SIZE_FORMAT, reasonable_max);
1576     }
1577     FLAG_SET_ERGO(uintx, MaxHeapSize, (uintx)reasonable_max);
1578   }
1579 
1580   // If the initial_heap_size has not been set with InitialHeapSize
1581   // or -Xms, then set it as fraction of the size of physical memory,
1582   // respecting the maximum and minimum sizes of the heap.
1583   if (FLAG_IS_DEFAULT(InitialHeapSize)) {
1584     julong reasonable_minimum = (julong)(OldSize + NewSize);
1585 
1586     reasonable_minimum = MIN2(reasonable_minimum, (julong)MaxHeapSize);
1587 
1588     reasonable_minimum = os::allocatable_physical_memory(reasonable_minimum);
1589 
1590     julong reasonable_initial = phys_mem / InitialRAMFraction;
1591 
1592     reasonable_initial = MAX2(reasonable_initial, reasonable_minimum);
1593     reasonable_initial = MIN2(reasonable_initial, (julong)MaxHeapSize);
1594 
1595     reasonable_initial = os::allocatable_physical_memory(reasonable_initial);
1596 
1597     if (PrintGCDetails && Verbose) {
1598       // Cannot use gclog_or_tty yet.
1599       tty->print_cr("  Initial heap size " SIZE_FORMAT, (uintx)reasonable_initial);
1600       tty->print_cr("  Minimum heap size " SIZE_FORMAT, (uintx)reasonable_minimum);
1601     }
1602     FLAG_SET_ERGO(uintx, InitialHeapSize, (uintx)reasonable_initial);
1603     set_min_heap_size((uintx)reasonable_minimum);
1604   }
1605 }
1606 
1607 // This must be called after ergonomics because we want bytecode rewriting
1608 // if the server compiler is used, or if UseSharedSpaces is disabled.
1609 void Arguments::set_bytecode_flags() {
1610   // Better not attempt to store into a read-only space.
1611   if (UseSharedSpaces) {
1612     FLAG_SET_DEFAULT(RewriteBytecodes, false);
1613     FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
1614   }
1615 
1616   if (!RewriteBytecodes) {
1617     FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
1618   }
1619 }
1620 
1621 // Aggressive optimization flags  -XX:+AggressiveOpts
1622 void Arguments::set_aggressive_opts_flags() {
1623 #ifdef COMPILER2
1624   if (AggressiveOpts || !FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
1625     if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
1626       FLAG_SET_DEFAULT(EliminateAutoBox, true);
1627     }
1628     if (FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
1629       FLAG_SET_DEFAULT(AutoBoxCacheMax, 20000);
1630     }
1631 
1632     // Feed the cache size setting into the JDK
1633     char buffer[1024];
1634     sprintf(buffer, "java.lang.Integer.IntegerCache.high=" INTX_FORMAT, AutoBoxCacheMax);
1635     add_property(buffer);
1636   }
1637   if (AggressiveOpts && FLAG_IS_DEFAULT(BiasedLockingStartupDelay)) {
1638     FLAG_SET_DEFAULT(BiasedLockingStartupDelay, 500);
1639   }
1640 #endif
1641 
1642   if (AggressiveOpts) {
1643 // Sample flag setting code
1644 //    if (FLAG_IS_DEFAULT(EliminateZeroing)) {
1645 //      FLAG_SET_DEFAULT(EliminateZeroing, true);
1646 //    }
1647   }
1648 }
1649 
1650 //===========================================================================================================
1651 // Parsing of java.compiler property
1652 
1653 void Arguments::process_java_compiler_argument(char* arg) {
1654   // For backwards compatibility, Djava.compiler=NONE or ""
1655   // causes us to switch to -Xint mode UNLESS -Xdebug
1656   // is also specified.
1657   if (strlen(arg) == 0 || strcasecmp(arg, "NONE") == 0) {
1658     set_java_compiler(true);    // "-Djava.compiler[=...]" most recently seen.
1659   }
1660 }
1661 
1662 void Arguments::process_java_launcher_argument(const char* launcher, void* extra_info) {
1663   _sun_java_launcher = strdup(launcher);
1664   if (strcmp("gamma", _sun_java_launcher) == 0) {
1665     _created_by_gamma_launcher = true;
1666   }
1667 }
1668 
1669 bool Arguments::created_by_java_launcher() {
1670   assert(_sun_java_launcher != NULL, "property must have value");
1671   return strcmp(DEFAULT_JAVA_LAUNCHER, _sun_java_launcher) != 0;
1672 }
1673 
1674 bool Arguments::created_by_gamma_launcher() {
1675   return _created_by_gamma_launcher;
1676 }
1677 
1678 //===========================================================================================================
1679 // Parsing of main arguments
1680 
1681 bool Arguments::verify_interval(uintx val, uintx min,
1682                                 uintx max, const char* name) {
1683   // Returns true iff value is in the inclusive interval [min..max]
1684   // false, otherwise.
1685   if (val >= min && val <= max) {
1686     return true;
1687   }
1688   jio_fprintf(defaultStream::error_stream(),
1689               "%s of " UINTX_FORMAT " is invalid; must be between " UINTX_FORMAT
1690               " and " UINTX_FORMAT "\n",
1691               name, val, min, max);
1692   return false;
1693 }
1694 
1695 bool Arguments::verify_min_value(intx val, intx min, const char* name) {
1696   // Returns true if given value is at least specified min threshold
1697   // false, otherwise.
1698   if (val >= min ) {
1699       return true;
1700   }
1701   jio_fprintf(defaultStream::error_stream(),
1702               "%s of " INTX_FORMAT " is invalid; must be at least " INTX_FORMAT "\n",
1703               name, val, min);
1704   return false;
1705 }
1706 
1707 bool Arguments::verify_percentage(uintx value, const char* name) {
1708   if (value <= 100) {
1709     return true;
1710   }
1711   jio_fprintf(defaultStream::error_stream(),
1712               "%s of " UINTX_FORMAT " is invalid; must be between 0 and 100\n",
1713               name, value);
1714   return false;
1715 }
1716 
1717 static void force_serial_gc() {
1718   FLAG_SET_DEFAULT(UseSerialGC, true);
1719   FLAG_SET_DEFAULT(UseParNewGC, false);
1720   FLAG_SET_DEFAULT(UseConcMarkSweepGC, false);
1721   FLAG_SET_DEFAULT(CMSIncrementalMode, false);  // special CMS suboption
1722   FLAG_SET_DEFAULT(UseParallelGC, false);
1723   FLAG_SET_DEFAULT(UseParallelOldGC, false);
1724   FLAG_SET_DEFAULT(UseG1GC, false);
1725 }
1726 
1727 static bool verify_serial_gc_flags() {
1728   return (UseSerialGC &&
1729         !(UseParNewGC || (UseConcMarkSweepGC || CMSIncrementalMode) || UseG1GC ||
1730           UseParallelGC || UseParallelOldGC));
1731 }
1732 
1733 // check if do gclog rotation
1734 // +UseGCLogFileRotation is a must,
1735 // no gc log rotation when log file not supplied or
1736 // NumberOfGCLogFiles is 0, or GCLogFileSize is 0
1737 void check_gclog_consistency() {
1738   if (UseGCLogFileRotation) {
1739     if ((Arguments::gc_log_filename() == NULL) ||
1740         (NumberOfGCLogFiles == 0)  ||
1741         (GCLogFileSize == 0)) {
1742       jio_fprintf(defaultStream::output_stream(),
1743                   "To enable GC log rotation, use -Xloggc:<filename> -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=<num_of_files> -XX:GCLogFileSize=<num_of_size>\n"
1744                   "where num_of_file > 0 and num_of_size > 0\n"
1745                   "GC log rotation is turned off\n");
1746       UseGCLogFileRotation = false;
1747     }
1748   }
1749 
1750   if (UseGCLogFileRotation && GCLogFileSize < 8*K) {
1751         FLAG_SET_CMDLINE(uintx, GCLogFileSize, 8*K);
1752         jio_fprintf(defaultStream::output_stream(),
1753                     "GCLogFileSize changed to minimum 8K\n");
1754   }
1755 }
1756 
1757 // Check consistency of GC selection
1758 bool Arguments::check_gc_consistency() {
1759   check_gclog_consistency();
1760   bool status = true;
1761   // Ensure that the user has not selected conflicting sets
1762   // of collectors. [Note: this check is merely a user convenience;
1763   // collectors over-ride each other so that only a non-conflicting
1764   // set is selected; however what the user gets is not what they
1765   // may have expected from the combination they asked for. It's
1766   // better to reduce user confusion by not allowing them to
1767   // select conflicting combinations.
1768   uint i = 0;
1769   if (UseSerialGC)                       i++;
1770   if (UseConcMarkSweepGC || UseParNewGC) i++;
1771   if (UseParallelGC || UseParallelOldGC) i++;
1772   if (UseG1GC)                           i++;
1773   if (i > 1) {
1774     jio_fprintf(defaultStream::error_stream(),
1775                 "Conflicting collector combinations in option list; "
1776                 "please refer to the release notes for the combinations "
1777                 "allowed\n");
1778     status = false;
1779   }
1780 
1781   return status;
1782 }
1783 
1784 // Check stack pages settings
1785 bool Arguments::check_stack_pages()
1786 {
1787   bool status = true;
1788   status = status && verify_min_value(StackYellowPages, 1, "StackYellowPages");
1789   status = status && verify_min_value(StackRedPages, 1, "StackRedPages");
1790   // greater stack shadow pages can't generate instruction to bang stack
1791   status = status && verify_interval(StackShadowPages, 1, 50, "StackShadowPages");
1792   return status;
1793 }
1794 
1795 // Check the consistency of vm_init_args
1796 bool Arguments::check_vm_args_consistency() {
1797   // Method for adding checks for flag consistency.
1798   // The intent is to warn the user of all possible conflicts,
1799   // before returning an error.
1800   // Note: Needs platform-dependent factoring.
1801   bool status = true;
1802 
1803 #if ( (defined(COMPILER2) && defined(SPARC)))
1804   // NOTE: The call to VM_Version_init depends on the fact that VM_Version_init
1805   // on sparc doesn't require generation of a stub as is the case on, e.g.,
1806   // x86.  Normally, VM_Version_init must be called from init_globals in
1807   // init.cpp, which is called by the initial java thread *after* arguments
1808   // have been parsed.  VM_Version_init gets called twice on sparc.
1809   extern void VM_Version_init();
1810   VM_Version_init();
1811   if (!VM_Version::has_v9()) {
1812     jio_fprintf(defaultStream::error_stream(),
1813                 "V8 Machine detected, Server requires V9\n");
1814     status = false;
1815   }
1816 #endif /* COMPILER2 && SPARC */
1817 
1818   // Allow both -XX:-UseStackBanging and -XX:-UseBoundThreads in non-product
1819   // builds so the cost of stack banging can be measured.
1820 #if (defined(PRODUCT) && defined(SOLARIS))
1821   if (!UseBoundThreads && !UseStackBanging) {
1822     jio_fprintf(defaultStream::error_stream(),
1823                 "-UseStackBanging conflicts with -UseBoundThreads\n");
1824 
1825      status = false;
1826   }
1827 #endif
1828 
1829   if (TLABRefillWasteFraction == 0) {
1830     jio_fprintf(defaultStream::error_stream(),
1831                 "TLABRefillWasteFraction should be a denominator, "
1832                 "not " SIZE_FORMAT "\n",
1833                 TLABRefillWasteFraction);
1834     status = false;
1835   }
1836 
1837   status = status && verify_percentage(AdaptiveSizePolicyWeight,
1838                               "AdaptiveSizePolicyWeight");
1839   status = status && verify_percentage(ThresholdTolerance, "ThresholdTolerance");
1840   status = status && verify_percentage(MinHeapFreeRatio, "MinHeapFreeRatio");
1841   status = status && verify_percentage(MaxHeapFreeRatio, "MaxHeapFreeRatio");
1842 
1843   if (MinHeapFreeRatio > MaxHeapFreeRatio) {
1844     jio_fprintf(defaultStream::error_stream(),
1845                 "MinHeapFreeRatio (" UINTX_FORMAT ") must be less than or "
1846                 "equal to MaxHeapFreeRatio (" UINTX_FORMAT ")\n",
1847                 MinHeapFreeRatio, MaxHeapFreeRatio);
1848     status = false;
1849   }
1850   // Keeping the heap 100% free is hard ;-) so limit it to 99%.
1851   MinHeapFreeRatio = MIN2(MinHeapFreeRatio, (uintx) 99);
1852 
1853   if (FullGCALot && FLAG_IS_DEFAULT(MarkSweepAlwaysCompactCount)) {
1854     MarkSweepAlwaysCompactCount = 1;  // Move objects every gc.
1855   }
1856 
1857   if (UseParallelOldGC && ParallelOldGCSplitALot) {
1858     // Settings to encourage splitting.
1859     if (!FLAG_IS_CMDLINE(NewRatio)) {
1860       FLAG_SET_CMDLINE(intx, NewRatio, 2);
1861     }
1862     if (!FLAG_IS_CMDLINE(ScavengeBeforeFullGC)) {
1863       FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
1864     }
1865   }
1866 
1867   status = status && verify_percentage(GCHeapFreeLimit, "GCHeapFreeLimit");
1868   status = status && verify_percentage(GCTimeLimit, "GCTimeLimit");
1869   if (GCTimeLimit == 100) {
1870     // Turn off gc-overhead-limit-exceeded checks
1871     FLAG_SET_DEFAULT(UseGCOverheadLimit, false);
1872   }
1873 
1874   status = status && verify_percentage(GCHeapFreeLimit, "GCHeapFreeLimit");
1875 
1876   status = status && check_gc_consistency();
1877   status = status && check_stack_pages();
1878 
1879   if (_has_alloc_profile) {
1880     if (UseParallelGC || UseParallelOldGC) {
1881       jio_fprintf(defaultStream::error_stream(),
1882                   "error:  invalid argument combination.\n"
1883                   "Allocation profiling (-Xaprof) cannot be used together with "
1884                   "Parallel GC (-XX:+UseParallelGC or -XX:+UseParallelOldGC).\n");
1885       status = false;
1886     }
1887     if (UseConcMarkSweepGC) {
1888       jio_fprintf(defaultStream::error_stream(),
1889                   "error:  invalid argument combination.\n"
1890                   "Allocation profiling (-Xaprof) cannot be used together with "
1891                   "the CMS collector (-XX:+UseConcMarkSweepGC).\n");
1892       status = false;
1893     }
1894   }
1895 
1896   if (CMSIncrementalMode) {
1897     if (!UseConcMarkSweepGC) {
1898       jio_fprintf(defaultStream::error_stream(),
1899                   "error:  invalid argument combination.\n"
1900                   "The CMS collector (-XX:+UseConcMarkSweepGC) must be "
1901                   "selected in order\nto use CMSIncrementalMode.\n");
1902       status = false;
1903     } else {
1904       status = status && verify_percentage(CMSIncrementalDutyCycle,
1905                                   "CMSIncrementalDutyCycle");
1906       status = status && verify_percentage(CMSIncrementalDutyCycleMin,
1907                                   "CMSIncrementalDutyCycleMin");
1908       status = status && verify_percentage(CMSIncrementalSafetyFactor,
1909                                   "CMSIncrementalSafetyFactor");
1910       status = status && verify_percentage(CMSIncrementalOffset,
1911                                   "CMSIncrementalOffset");
1912       status = status && verify_percentage(CMSExpAvgFactor,
1913                                   "CMSExpAvgFactor");
1914       // If it was not set on the command line, set
1915       // CMSInitiatingOccupancyFraction to 1 so icms can initiate cycles early.
1916       if (CMSInitiatingOccupancyFraction < 0) {
1917         FLAG_SET_DEFAULT(CMSInitiatingOccupancyFraction, 1);
1918       }
1919     }
1920   }
1921 
1922   // CMS space iteration, which FLSVerifyAllHeapreferences entails,
1923   // insists that we hold the requisite locks so that the iteration is
1924   // MT-safe. For the verification at start-up and shut-down, we don't
1925   // yet have a good way of acquiring and releasing these locks,
1926   // which are not visible at the CollectedHeap level. We want to
1927   // be able to acquire these locks and then do the iteration rather
1928   // than just disable the lock verification. This will be fixed under
1929   // bug 4788986.
1930   if (UseConcMarkSweepGC && FLSVerifyAllHeapReferences) {
1931     if (VerifyGCStartAt == 0) {
1932       warning("Heap verification at start-up disabled "
1933               "(due to current incompatibility with FLSVerifyAllHeapReferences)");
1934       VerifyGCStartAt = 1;      // Disable verification at start-up
1935     }
1936     if (VerifyBeforeExit) {
1937       warning("Heap verification at shutdown disabled "
1938               "(due to current incompatibility with FLSVerifyAllHeapReferences)");
1939       VerifyBeforeExit = false; // Disable verification at shutdown
1940     }
1941   }
1942 
1943   // Note: only executed in non-PRODUCT mode
1944   if (!UseAsyncConcMarkSweepGC &&
1945       (ExplicitGCInvokesConcurrent ||
1946        ExplicitGCInvokesConcurrentAndUnloadsClasses)) {
1947     jio_fprintf(defaultStream::error_stream(),
1948                 "error: +ExplicitGCInvokesConcurrent[AndUnloadsClasses] conflicts"
1949                 " with -UseAsyncConcMarkSweepGC");
1950     status = false;
1951   }
1952 
1953   status = status && verify_min_value(ParGCArrayScanChunk, 1, "ParGCArrayScanChunk");
1954 
1955 #ifndef SERIALGC
1956   if (UseG1GC) {
1957     status = status && verify_percentage(InitiatingHeapOccupancyPercent,
1958                                          "InitiatingHeapOccupancyPercent");
1959     status = status && verify_min_value(G1RefProcDrainInterval, 1,
1960                                         "G1RefProcDrainInterval");
1961     status = status && verify_min_value((intx)G1ConcMarkStepDurationMillis, 1,
1962                                         "G1ConcMarkStepDurationMillis");
1963   }
1964 #endif
1965 
1966   status = status && verify_interval(RefDiscoveryPolicy,
1967                                      ReferenceProcessor::DiscoveryPolicyMin,
1968                                      ReferenceProcessor::DiscoveryPolicyMax,
1969                                      "RefDiscoveryPolicy");
1970 
1971   // Limit the lower bound of this flag to 1 as it is used in a division
1972   // expression.
1973   status = status && verify_interval(TLABWasteTargetPercent,
1974                                      1, 100, "TLABWasteTargetPercent");
1975 
1976   status = status && verify_object_alignment();
1977 
1978   status = status && verify_min_value(ClassMetaspaceSize, 1*M,
1979                                       "ClassMetaspaceSize");
1980 
1981   return status;
1982 }
1983 
1984 bool Arguments::is_bad_option(const JavaVMOption* option, jboolean ignore,
1985   const char* option_type) {
1986   if (ignore) return false;
1987 
1988   const char* spacer = " ";
1989   if (option_type == NULL) {
1990     option_type = ++spacer; // Set both to the empty string.
1991   }
1992 
1993   if (os::obsolete_option(option)) {
1994     jio_fprintf(defaultStream::error_stream(),
1995                 "Obsolete %s%soption: %s\n", option_type, spacer,
1996       option->optionString);
1997     return false;
1998   } else {
1999     jio_fprintf(defaultStream::error_stream(),
2000                 "Unrecognized %s%soption: %s\n", option_type, spacer,
2001       option->optionString);
2002     return true;
2003   }
2004 }
2005 
2006 static const char* user_assertion_options[] = {
2007   "-da", "-ea", "-disableassertions", "-enableassertions", 0
2008 };
2009 
2010 static const char* system_assertion_options[] = {
2011   "-dsa", "-esa", "-disablesystemassertions", "-enablesystemassertions", 0
2012 };
2013 
2014 // Return true if any of the strings in null-terminated array 'names' matches.
2015 // If tail_allowed is true, then the tail must begin with a colon; otherwise,
2016 // the option must match exactly.
2017 static bool match_option(const JavaVMOption* option, const char** names, const char** tail,
2018   bool tail_allowed) {
2019   for (/* empty */; *names != NULL; ++names) {
2020     if (match_option(option, *names, tail)) {
2021       if (**tail == '\0' || tail_allowed && **tail == ':') {
2022         return true;
2023       }
2024     }
2025   }
2026   return false;
2027 }
2028 
2029 bool Arguments::parse_uintx(const char* value,
2030                             uintx* uintx_arg,
2031                             uintx min_size) {
2032 
2033   // Check the sign first since atomull() parses only unsigned values.
2034   bool value_is_positive = !(*value == '-');
2035 
2036   if (value_is_positive) {
2037     julong n;
2038     bool good_return = atomull(value, &n);
2039     if (good_return) {
2040       bool above_minimum = n >= min_size;
2041       bool value_is_too_large = n > max_uintx;
2042 
2043       if (above_minimum && !value_is_too_large) {
2044         *uintx_arg = n;
2045         return true;
2046       }
2047     }
2048   }
2049   return false;
2050 }
2051 
2052 Arguments::ArgsRange Arguments::parse_memory_size(const char* s,
2053                                                   julong* long_arg,
2054                                                   julong min_size) {
2055   if (!atomull(s, long_arg)) return arg_unreadable;
2056   return check_memory_size(*long_arg, min_size);
2057 }
2058 
2059 // Parse JavaVMInitArgs structure
2060 
2061 jint Arguments::parse_vm_init_args(const JavaVMInitArgs* args) {
2062   // For components of the system classpath.
2063   SysClassPath scp(Arguments::get_sysclasspath());
2064   bool scp_assembly_required = false;
2065 
2066   // Save default settings for some mode flags
2067   Arguments::_AlwaysCompileLoopMethods = AlwaysCompileLoopMethods;
2068   Arguments::_UseOnStackReplacement    = UseOnStackReplacement;
2069   Arguments::_ClipInlining             = ClipInlining;
2070   Arguments::_BackgroundCompilation    = BackgroundCompilation;
2071 
2072   // Setup flags for mixed which is the default
2073   set_mode_flags(_mixed);
2074 
2075   // Parse JAVA_TOOL_OPTIONS environment variable (if present)
2076   jint result = parse_java_tool_options_environment_variable(&scp, &scp_assembly_required);
2077   if (result != JNI_OK) {
2078     return result;
2079   }
2080 
2081   // Parse JavaVMInitArgs structure passed in
2082   result = parse_each_vm_init_arg(args, &scp, &scp_assembly_required, COMMAND_LINE);
2083   if (result != JNI_OK) {
2084     return result;
2085   }
2086 
2087   if (AggressiveOpts) {
2088     // Insert alt-rt.jar between user-specified bootclasspath
2089     // prefix and the default bootclasspath.  os::set_boot_path()
2090     // uses meta_index_dir as the default bootclasspath directory.
2091     const char* altclasses_jar = "alt-rt.jar";
2092     size_t altclasses_path_len = strlen(get_meta_index_dir()) + 1 +
2093                                  strlen(altclasses_jar);
2094     char* altclasses_path = NEW_C_HEAP_ARRAY(char, altclasses_path_len, mtInternal);
2095     strcpy(altclasses_path, get_meta_index_dir());
2096     strcat(altclasses_path, altclasses_jar);
2097     scp.add_suffix_to_prefix(altclasses_path);
2098     scp_assembly_required = true;
2099     FREE_C_HEAP_ARRAY(char, altclasses_path, mtInternal);
2100   }
2101 
2102   if (WhiteBoxAPI) {
2103     // Append wb.jar to bootclasspath if enabled
2104     const char* wb_jar = "wb.jar";
2105     size_t wb_path_len = strlen(get_meta_index_dir()) + 1 +
2106                          strlen(wb_jar);
2107     char* wb_path = NEW_C_HEAP_ARRAY(char, wb_path_len, mtInternal);
2108     strcpy(wb_path, get_meta_index_dir());
2109     strcat(wb_path, wb_jar);
2110     scp.add_suffix(wb_path);
2111     scp_assembly_required = true;
2112     FREE_C_HEAP_ARRAY(char, wb_path, mtInternal);
2113   }
2114 
2115   // Parse _JAVA_OPTIONS environment variable (if present) (mimics classic VM)
2116   result = parse_java_options_environment_variable(&scp, &scp_assembly_required);
2117   if (result != JNI_OK) {
2118     return result;
2119   }
2120 
2121   // Do final processing now that all arguments have been parsed
2122   result = finalize_vm_init_args(&scp, scp_assembly_required);
2123   if (result != JNI_OK) {
2124     return result;
2125   }
2126 
2127   return JNI_OK;
2128 }
2129 
2130 jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args,
2131                                        SysClassPath* scp_p,
2132                                        bool* scp_assembly_required_p,
2133                                        FlagValueOrigin origin) {
2134   // Remaining part of option string
2135   const char* tail;
2136 
2137   // iterate over arguments
2138   for (int index = 0; index < args->nOptions; index++) {
2139     bool is_absolute_path = false;  // for -agentpath vs -agentlib
2140 
2141     const JavaVMOption* option = args->options + index;
2142 
2143     if (!match_option(option, "-Djava.class.path", &tail) &&
2144         !match_option(option, "-Dsun.java.command", &tail) &&
2145         !match_option(option, "-Dsun.java.launcher", &tail)) {
2146 
2147         // add all jvm options to the jvm_args string. This string
2148         // is used later to set the java.vm.args PerfData string constant.
2149         // the -Djava.class.path and the -Dsun.java.command options are
2150         // omitted from jvm_args string as each have their own PerfData
2151         // string constant object.
2152         build_jvm_args(option->optionString);
2153     }
2154 
2155     // -verbose:[class/gc/jni]
2156     if (match_option(option, "-verbose", &tail)) {
2157       if (!strcmp(tail, ":class") || !strcmp(tail, "")) {
2158         FLAG_SET_CMDLINE(bool, TraceClassLoading, true);
2159         FLAG_SET_CMDLINE(bool, TraceClassUnloading, true);
2160       } else if (!strcmp(tail, ":gc")) {
2161         FLAG_SET_CMDLINE(bool, PrintGC, true);
2162       } else if (!strcmp(tail, ":jni")) {
2163         FLAG_SET_CMDLINE(bool, PrintJNIResolving, true);
2164       }
2165     // -da / -ea / -disableassertions / -enableassertions
2166     // These accept an optional class/package name separated by a colon, e.g.,
2167     // -da:java.lang.Thread.
2168     } else if (match_option(option, user_assertion_options, &tail, true)) {
2169       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2170       if (*tail == '\0') {
2171         JavaAssertions::setUserClassDefault(enable);
2172       } else {
2173         assert(*tail == ':', "bogus match by match_option()");
2174         JavaAssertions::addOption(tail + 1, enable);
2175       }
2176     // -dsa / -esa / -disablesystemassertions / -enablesystemassertions
2177     } else if (match_option(option, system_assertion_options, &tail, false)) {
2178       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2179       JavaAssertions::setSystemClassDefault(enable);
2180     // -bootclasspath:
2181     } else if (match_option(option, "-Xbootclasspath:", &tail)) {
2182       scp_p->reset_path(tail);
2183       *scp_assembly_required_p = true;
2184     // -bootclasspath/a:
2185     } else if (match_option(option, "-Xbootclasspath/a:", &tail)) {
2186       scp_p->add_suffix(tail);
2187       *scp_assembly_required_p = true;
2188     // -bootclasspath/p:
2189     } else if (match_option(option, "-Xbootclasspath/p:", &tail)) {
2190       scp_p->add_prefix(tail);
2191       *scp_assembly_required_p = true;
2192     // -Xrun
2193     } else if (match_option(option, "-Xrun", &tail)) {
2194       if (tail != NULL) {
2195         const char* pos = strchr(tail, ':');
2196         size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
2197         char* name = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len + 1, mtInternal), tail, len);
2198         name[len] = '\0';
2199 
2200         char *options = NULL;
2201         if(pos != NULL) {
2202           size_t len2 = strlen(pos+1) + 1; // options start after ':'.  Final zero must be copied.
2203           options = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len2, mtInternal), pos+1, len2);
2204         }
2205 #ifdef JVMTI_KERNEL
2206         if ((strcmp(name, "hprof") == 0) || (strcmp(name, "jdwp") == 0)) {
2207           warning("profiling and debugging agents are not supported with Kernel VM");
2208         } else
2209 #endif // JVMTI_KERNEL
2210         add_init_library(name, options);
2211       }
2212     // -agentlib and -agentpath
2213     } else if (match_option(option, "-agentlib:", &tail) ||
2214           (is_absolute_path = match_option(option, "-agentpath:", &tail))) {
2215       if(tail != NULL) {
2216         const char* pos = strchr(tail, '=');
2217         size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
2218         char* name = strncpy(NEW_C_HEAP_ARRAY(char, len + 1, mtInternal), tail, len);
2219         name[len] = '\0';
2220 
2221         char *options = NULL;
2222         if(pos != NULL) {
2223           options = strcpy(NEW_C_HEAP_ARRAY(char, strlen(pos + 1) + 1, mtInternal), pos + 1);
2224         }
2225 #ifdef JVMTI_KERNEL
2226         if ((strcmp(name, "hprof") == 0) || (strcmp(name, "jdwp") == 0)) {
2227           warning("profiling and debugging agents are not supported with Kernel VM");
2228         } else
2229 #endif // JVMTI_KERNEL
2230         add_init_agent(name, options, is_absolute_path);
2231 
2232       }
2233     // -javaagent
2234     } else if (match_option(option, "-javaagent:", &tail)) {
2235       if(tail != NULL) {
2236         char *options = strcpy(NEW_C_HEAP_ARRAY(char, strlen(tail) + 1, mtInternal), tail);
2237         add_init_agent("instrument", options, false);
2238       }
2239     // -Xnoclassgc
2240     } else if (match_option(option, "-Xnoclassgc", &tail)) {
2241       FLAG_SET_CMDLINE(bool, ClassUnloading, false);
2242     // -Xincgc: i-CMS
2243     } else if (match_option(option, "-Xincgc", &tail)) {
2244       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, true);
2245       FLAG_SET_CMDLINE(bool, CMSIncrementalMode, true);
2246     // -Xnoincgc: no i-CMS
2247     } else if (match_option(option, "-Xnoincgc", &tail)) {
2248       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, false);
2249       FLAG_SET_CMDLINE(bool, CMSIncrementalMode, false);
2250     // -Xconcgc
2251     } else if (match_option(option, "-Xconcgc", &tail)) {
2252       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, true);
2253     // -Xnoconcgc
2254     } else if (match_option(option, "-Xnoconcgc", &tail)) {
2255       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, false);
2256     // -Xbatch
2257     } else if (match_option(option, "-Xbatch", &tail)) {
2258       FLAG_SET_CMDLINE(bool, BackgroundCompilation, false);
2259     // -Xmn for compatibility with other JVM vendors
2260     } else if (match_option(option, "-Xmn", &tail)) {
2261       julong long_initial_eden_size = 0;
2262       ArgsRange errcode = parse_memory_size(tail, &long_initial_eden_size, 1);
2263       if (errcode != arg_in_range) {
2264         jio_fprintf(defaultStream::error_stream(),
2265                     "Invalid initial eden size: %s\n", option->optionString);
2266         describe_range_error(errcode);
2267         return JNI_EINVAL;
2268       }
2269       FLAG_SET_CMDLINE(uintx, MaxNewSize, (uintx)long_initial_eden_size);
2270       FLAG_SET_CMDLINE(uintx, NewSize, (uintx)long_initial_eden_size);
2271     // -Xms
2272     } else if (match_option(option, "-Xms", &tail)) {
2273       julong long_initial_heap_size = 0;
2274       ArgsRange errcode = parse_memory_size(tail, &long_initial_heap_size, 1);
2275       if (errcode != arg_in_range) {
2276         jio_fprintf(defaultStream::error_stream(),
2277                     "Invalid initial heap size: %s\n", option->optionString);
2278         describe_range_error(errcode);
2279         return JNI_EINVAL;
2280       }
2281       FLAG_SET_CMDLINE(uintx, InitialHeapSize, (uintx)long_initial_heap_size);
2282       // Currently the minimum size and the initial heap sizes are the same.
2283       set_min_heap_size(InitialHeapSize);
2284     // -Xmx
2285     } else if (match_option(option, "-Xmx", &tail)) {
2286       julong long_max_heap_size = 0;
2287       ArgsRange errcode = parse_memory_size(tail, &long_max_heap_size, 1);
2288       if (errcode != arg_in_range) {
2289         jio_fprintf(defaultStream::error_stream(),
2290                     "Invalid maximum heap size: %s\n", option->optionString);
2291         describe_range_error(errcode);
2292         return JNI_EINVAL;
2293       }
2294       FLAG_SET_CMDLINE(uintx, MaxHeapSize, (uintx)long_max_heap_size);
2295     // Xmaxf
2296     } else if (match_option(option, "-Xmaxf", &tail)) {
2297       int maxf = (int)(atof(tail) * 100);
2298       if (maxf < 0 || maxf > 100) {
2299         jio_fprintf(defaultStream::error_stream(),
2300                     "Bad max heap free percentage size: %s\n",
2301                     option->optionString);
2302         return JNI_EINVAL;
2303       } else {
2304         FLAG_SET_CMDLINE(uintx, MaxHeapFreeRatio, maxf);
2305       }
2306     // Xminf
2307     } else if (match_option(option, "-Xminf", &tail)) {
2308       int minf = (int)(atof(tail) * 100);
2309       if (minf < 0 || minf > 100) {
2310         jio_fprintf(defaultStream::error_stream(),
2311                     "Bad min heap free percentage size: %s\n",
2312                     option->optionString);
2313         return JNI_EINVAL;
2314       } else {
2315         FLAG_SET_CMDLINE(uintx, MinHeapFreeRatio, minf);
2316       }
2317     // -Xss
2318     } else if (match_option(option, "-Xss", &tail)) {
2319       julong long_ThreadStackSize = 0;
2320       ArgsRange errcode = parse_memory_size(tail, &long_ThreadStackSize, 1000);
2321       if (errcode != arg_in_range) {
2322         jio_fprintf(defaultStream::error_stream(),
2323                     "Invalid thread stack size: %s\n", option->optionString);
2324         describe_range_error(errcode);
2325         return JNI_EINVAL;
2326       }
2327       // Internally track ThreadStackSize in units of 1024 bytes.
2328       FLAG_SET_CMDLINE(intx, ThreadStackSize,
2329                               round_to((int)long_ThreadStackSize, K) / K);
2330     // -Xoss
2331     } else if (match_option(option, "-Xoss", &tail)) {
2332           // HotSpot does not have separate native and Java stacks, ignore silently for compatibility
2333     // -Xmaxjitcodesize
2334     } else if (match_option(option, "-Xmaxjitcodesize", &tail) ||
2335                match_option(option, "-XX:ReservedCodeCacheSize=", &tail)) {
2336       julong long_ReservedCodeCacheSize = 0;
2337       ArgsRange errcode = parse_memory_size(tail, &long_ReservedCodeCacheSize,
2338                                             (size_t)InitialCodeCacheSize);
2339       if (errcode != arg_in_range) {
2340         jio_fprintf(defaultStream::error_stream(),
2341                     "Invalid maximum code cache size: %s. Should be greater than InitialCodeCacheSize=%dK\n",
2342                     option->optionString, InitialCodeCacheSize/K);
2343         describe_range_error(errcode);
2344         return JNI_EINVAL;
2345       }
2346       FLAG_SET_CMDLINE(uintx, ReservedCodeCacheSize, (uintx)long_ReservedCodeCacheSize);
2347     // -green
2348     } else if (match_option(option, "-green", &tail)) {
2349       jio_fprintf(defaultStream::error_stream(),
2350                   "Green threads support not available\n");
2351           return JNI_EINVAL;
2352     // -native
2353     } else if (match_option(option, "-native", &tail)) {
2354           // HotSpot always uses native threads, ignore silently for compatibility
2355     // -Xsqnopause
2356     } else if (match_option(option, "-Xsqnopause", &tail)) {
2357           // EVM option, ignore silently for compatibility
2358     // -Xrs
2359     } else if (match_option(option, "-Xrs", &tail)) {
2360           // Classic/EVM option, new functionality
2361       FLAG_SET_CMDLINE(bool, ReduceSignalUsage, true);
2362     } else if (match_option(option, "-Xusealtsigs", &tail)) {
2363           // change default internal VM signals used - lower case for back compat
2364       FLAG_SET_CMDLINE(bool, UseAltSigs, true);
2365     // -Xoptimize
2366     } else if (match_option(option, "-Xoptimize", &tail)) {
2367           // EVM option, ignore silently for compatibility
2368     // -Xprof
2369     } else if (match_option(option, "-Xprof", &tail)) {
2370 #ifndef FPROF_KERNEL
2371       _has_profile = true;
2372 #else // FPROF_KERNEL
2373       // do we have to exit?
2374       warning("Kernel VM does not support flat profiling.");
2375 #endif // FPROF_KERNEL
2376     // -Xaprof
2377     } else if (match_option(option, "-Xaprof", &tail)) {
2378       _has_alloc_profile = true;
2379     // -Xconcurrentio
2380     } else if (match_option(option, "-Xconcurrentio", &tail)) {
2381       FLAG_SET_CMDLINE(bool, UseLWPSynchronization, true);
2382       FLAG_SET_CMDLINE(bool, BackgroundCompilation, false);
2383       FLAG_SET_CMDLINE(intx, DeferThrSuspendLoopCount, 1);
2384       FLAG_SET_CMDLINE(bool, UseTLAB, false);
2385       FLAG_SET_CMDLINE(uintx, NewSizeThreadIncrease, 16 * K);  // 20Kb per thread added to new generation
2386 
2387       // -Xinternalversion
2388     } else if (match_option(option, "-Xinternalversion", &tail)) {
2389       jio_fprintf(defaultStream::output_stream(), "%s\n",
2390                   VM_Version::internal_vm_info_string());
2391       vm_exit(0);
2392 #ifndef PRODUCT
2393     // -Xprintflags
2394     } else if (match_option(option, "-Xprintflags", &tail)) {
2395       CommandLineFlags::printFlags(tty, false);
2396       vm_exit(0);
2397 #endif
2398     // -D
2399     } else if (match_option(option, "-D", &tail)) {
2400       if (!add_property(tail)) {
2401         return JNI_ENOMEM;
2402       }
2403       // Out of the box management support
2404       if (match_option(option, "-Dcom.sun.management", &tail)) {
2405         FLAG_SET_CMDLINE(bool, ManagementServer, true);
2406       }
2407     // -Xint
2408     } else if (match_option(option, "-Xint", &tail)) {
2409           set_mode_flags(_int);
2410     // -Xmixed
2411     } else if (match_option(option, "-Xmixed", &tail)) {
2412           set_mode_flags(_mixed);
2413     // -Xcomp
2414     } else if (match_option(option, "-Xcomp", &tail)) {
2415       // for testing the compiler; turn off all flags that inhibit compilation
2416           set_mode_flags(_comp);
2417 
2418     // -Xshare:dump
2419     } else if (match_option(option, "-Xshare:dump", &tail)) {
2420 #if defined(KERNEL)
2421       vm_exit_during_initialization(
2422           "Dumping a shared archive is not supported on the Kernel JVM.", NULL);
2423 #else
2424       FLAG_SET_CMDLINE(bool, DumpSharedSpaces, true);
2425       set_mode_flags(_int);     // Prevent compilation, which creates objects
2426 #endif
2427     // -Xshare:on
2428     } else if (match_option(option, "-Xshare:on", &tail)) {
2429       FLAG_SET_CMDLINE(bool, UseSharedSpaces, true);
2430       FLAG_SET_CMDLINE(bool, RequireSharedSpaces, true);
2431     // -Xshare:auto
2432     } else if (match_option(option, "-Xshare:auto", &tail)) {
2433       FLAG_SET_CMDLINE(bool, UseSharedSpaces, true);
2434       FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false);
2435     // -Xshare:off
2436     } else if (match_option(option, "-Xshare:off", &tail)) {
2437       FLAG_SET_CMDLINE(bool, UseSharedSpaces, false);
2438       FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false);
2439 
2440     // -Xverify
2441     } else if (match_option(option, "-Xverify", &tail)) {
2442       if (strcmp(tail, ":all") == 0 || strcmp(tail, "") == 0) {
2443         FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, true);
2444         FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true);
2445       } else if (strcmp(tail, ":remote") == 0) {
2446         FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false);
2447         FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true);
2448       } else if (strcmp(tail, ":none") == 0) {
2449         FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false);
2450         FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, false);
2451       } else if (is_bad_option(option, args->ignoreUnrecognized, "verification")) {
2452         return JNI_EINVAL;
2453       }
2454     // -Xdebug
2455     } else if (match_option(option, "-Xdebug", &tail)) {
2456       // note this flag has been used, then ignore
2457       set_xdebug_mode(true);
2458     // -Xnoagent
2459     } else if (match_option(option, "-Xnoagent", &tail)) {
2460       // For compatibility with classic. HotSpot refuses to load the old style agent.dll.
2461     } else if (match_option(option, "-Xboundthreads", &tail)) {
2462       // Bind user level threads to kernel threads (Solaris only)
2463       FLAG_SET_CMDLINE(bool, UseBoundThreads, true);
2464     } else if (match_option(option, "-Xloggc:", &tail)) {
2465       // Redirect GC output to the file. -Xloggc:<filename>
2466       // ostream_init_log(), when called will use this filename
2467       // to initialize a fileStream.
2468       _gc_log_filename = strdup(tail);
2469       FLAG_SET_CMDLINE(bool, PrintGC, true);
2470       FLAG_SET_CMDLINE(bool, PrintGCTimeStamps, true);
2471 
2472     // JNI hooks
2473     } else if (match_option(option, "-Xcheck", &tail)) {
2474       if (!strcmp(tail, ":jni")) {
2475         CheckJNICalls = true;
2476       } else if (is_bad_option(option, args->ignoreUnrecognized,
2477                                      "check")) {
2478         return JNI_EINVAL;
2479       }
2480     } else if (match_option(option, "vfprintf", &tail)) {
2481       _vfprintf_hook = CAST_TO_FN_PTR(vfprintf_hook_t, option->extraInfo);
2482     } else if (match_option(option, "exit", &tail)) {
2483       _exit_hook = CAST_TO_FN_PTR(exit_hook_t, option->extraInfo);
2484     } else if (match_option(option, "abort", &tail)) {
2485       _abort_hook = CAST_TO_FN_PTR(abort_hook_t, option->extraInfo);
2486     // -XX:+AggressiveHeap
2487     } else if (match_option(option, "-XX:+AggressiveHeap", &tail)) {
2488 
2489       // This option inspects the machine and attempts to set various
2490       // parameters to be optimal for long-running, memory allocation
2491       // intensive jobs.  It is intended for machines with large
2492       // amounts of cpu and memory.
2493 
2494       // initHeapSize is needed since _initial_heap_size is 4 bytes on a 32 bit
2495       // VM, but we may not be able to represent the total physical memory
2496       // available (like having 8gb of memory on a box but using a 32bit VM).
2497       // Thus, we need to make sure we're using a julong for intermediate
2498       // calculations.
2499       julong initHeapSize;
2500       julong total_memory = os::physical_memory();
2501 
2502       if (total_memory < (julong)256*M) {
2503         jio_fprintf(defaultStream::error_stream(),
2504                     "You need at least 256mb of memory to use -XX:+AggressiveHeap\n");
2505         vm_exit(1);
2506       }
2507 
2508       // The heap size is half of available memory, or (at most)
2509       // all of possible memory less 160mb (leaving room for the OS
2510       // when using ISM).  This is the maximum; because adaptive sizing
2511       // is turned on below, the actual space used may be smaller.
2512 
2513       initHeapSize = MIN2(total_memory / (julong)2,
2514                           total_memory - (julong)160*M);
2515 
2516       // Make sure that if we have a lot of memory we cap the 32 bit
2517       // process space.  The 64bit VM version of this function is a nop.
2518       initHeapSize = os::allocatable_physical_memory(initHeapSize);
2519 
2520       if (FLAG_IS_DEFAULT(MaxHeapSize)) {
2521          FLAG_SET_CMDLINE(uintx, MaxHeapSize, initHeapSize);
2522          FLAG_SET_CMDLINE(uintx, InitialHeapSize, initHeapSize);
2523          // Currently the minimum size and the initial heap sizes are the same.
2524          set_min_heap_size(initHeapSize);
2525       }
2526       if (FLAG_IS_DEFAULT(NewSize)) {
2527          // Make the young generation 3/8ths of the total heap.
2528          FLAG_SET_CMDLINE(uintx, NewSize,
2529                                 ((julong)MaxHeapSize / (julong)8) * (julong)3);
2530          FLAG_SET_CMDLINE(uintx, MaxNewSize, NewSize);
2531       }
2532 
2533       FLAG_SET_DEFAULT(UseLargePages, true);
2534 
2535       // Increase some data structure sizes for efficiency
2536       FLAG_SET_CMDLINE(uintx, BaseFootPrintEstimate, MaxHeapSize);
2537       FLAG_SET_CMDLINE(bool, ResizeTLAB, false);
2538       FLAG_SET_CMDLINE(uintx, TLABSize, 256*K);
2539 
2540       // See the OldPLABSize comment below, but replace 'after promotion'
2541       // with 'after copying'.  YoungPLABSize is the size of the survivor
2542       // space per-gc-thread buffers.  The default is 4kw.
2543       FLAG_SET_CMDLINE(uintx, YoungPLABSize, 256*K);      // Note: this is in words
2544 
2545       // OldPLABSize is the size of the buffers in the old gen that
2546       // UseParallelGC uses to promote live data that doesn't fit in the
2547       // survivor spaces.  At any given time, there's one for each gc thread.
2548       // The default size is 1kw. These buffers are rarely used, since the
2549       // survivor spaces are usually big enough.  For specjbb, however, there
2550       // are occasions when there's lots of live data in the young gen
2551       // and we end up promoting some of it.  We don't have a definite
2552       // explanation for why bumping OldPLABSize helps, but the theory
2553       // is that a bigger PLAB results in retaining something like the
2554       // original allocation order after promotion, which improves mutator
2555       // locality.  A minor effect may be that larger PLABs reduce the
2556       // number of PLAB allocation events during gc.  The value of 8kw
2557       // was arrived at by experimenting with specjbb.
2558       FLAG_SET_CMDLINE(uintx, OldPLABSize, 8*K);  // Note: this is in words
2559 
2560       // Enable parallel GC and adaptive generation sizing
2561       FLAG_SET_CMDLINE(bool, UseParallelGC, true);
2562       FLAG_SET_DEFAULT(ParallelGCThreads,
2563                        Abstract_VM_Version::parallel_worker_threads());
2564 
2565       // Encourage steady state memory management
2566       FLAG_SET_CMDLINE(uintx, ThresholdTolerance, 100);
2567 
2568       // This appears to improve mutator locality
2569       FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
2570 
2571       // Get around early Solaris scheduling bug
2572       // (affinity vs other jobs on system)
2573       // but disallow DR and offlining (5008695).
2574       FLAG_SET_CMDLINE(bool, BindGCTaskThreadsToCPUs, true);
2575 
2576     } else if (match_option(option, "-XX:+NeverTenure", &tail)) {
2577       // The last option must always win.
2578       FLAG_SET_CMDLINE(bool, AlwaysTenure, false);
2579       FLAG_SET_CMDLINE(bool, NeverTenure, true);
2580     } else if (match_option(option, "-XX:+AlwaysTenure", &tail)) {
2581       // The last option must always win.
2582       FLAG_SET_CMDLINE(bool, NeverTenure, false);
2583       FLAG_SET_CMDLINE(bool, AlwaysTenure, true);
2584     } else if (match_option(option, "-XX:+CMSPermGenSweepingEnabled", &tail) ||
2585                match_option(option, "-XX:-CMSPermGenSweepingEnabled", &tail)) {
2586       jio_fprintf(defaultStream::error_stream(),
2587         "Please use CMSClassUnloadingEnabled in place of "
2588         "CMSPermGenSweepingEnabled in the future\n");
2589     } else if (match_option(option, "-XX:+UseGCTimeLimit", &tail)) {
2590       FLAG_SET_CMDLINE(bool, UseGCOverheadLimit, true);
2591       jio_fprintf(defaultStream::error_stream(),
2592         "Please use -XX:+UseGCOverheadLimit in place of "
2593         "-XX:+UseGCTimeLimit in the future\n");
2594     } else if (match_option(option, "-XX:-UseGCTimeLimit", &tail)) {
2595       FLAG_SET_CMDLINE(bool, UseGCOverheadLimit, false);
2596       jio_fprintf(defaultStream::error_stream(),
2597         "Please use -XX:-UseGCOverheadLimit in place of "
2598         "-XX:-UseGCTimeLimit in the future\n");
2599     // The TLE options are for compatibility with 1.3 and will be
2600     // removed without notice in a future release.  These options
2601     // are not to be documented.
2602     } else if (match_option(option, "-XX:MaxTLERatio=", &tail)) {
2603       // No longer used.
2604     } else if (match_option(option, "-XX:+ResizeTLE", &tail)) {
2605       FLAG_SET_CMDLINE(bool, ResizeTLAB, true);
2606     } else if (match_option(option, "-XX:-ResizeTLE", &tail)) {
2607       FLAG_SET_CMDLINE(bool, ResizeTLAB, false);
2608     } else if (match_option(option, "-XX:+PrintTLE", &tail)) {
2609       FLAG_SET_CMDLINE(bool, PrintTLAB, true);
2610     } else if (match_option(option, "-XX:-PrintTLE", &tail)) {
2611       FLAG_SET_CMDLINE(bool, PrintTLAB, false);
2612     } else if (match_option(option, "-XX:TLEFragmentationRatio=", &tail)) {
2613       // No longer used.
2614     } else if (match_option(option, "-XX:TLESize=", &tail)) {
2615       julong long_tlab_size = 0;
2616       ArgsRange errcode = parse_memory_size(tail, &long_tlab_size, 1);
2617       if (errcode != arg_in_range) {
2618         jio_fprintf(defaultStream::error_stream(),
2619                     "Invalid TLAB size: %s\n", option->optionString);
2620         describe_range_error(errcode);
2621         return JNI_EINVAL;
2622       }
2623       FLAG_SET_CMDLINE(uintx, TLABSize, long_tlab_size);
2624     } else if (match_option(option, "-XX:TLEThreadRatio=", &tail)) {
2625       // No longer used.
2626     } else if (match_option(option, "-XX:+UseTLE", &tail)) {
2627       FLAG_SET_CMDLINE(bool, UseTLAB, true);
2628     } else if (match_option(option, "-XX:-UseTLE", &tail)) {
2629       FLAG_SET_CMDLINE(bool, UseTLAB, false);
2630 SOLARIS_ONLY(
2631     } else if (match_option(option, "-XX:+UsePermISM", &tail)) {
2632       warning("-XX:+UsePermISM is obsolete.");
2633       FLAG_SET_CMDLINE(bool, UseISM, true);
2634     } else if (match_option(option, "-XX:-UsePermISM", &tail)) {
2635       FLAG_SET_CMDLINE(bool, UseISM, false);
2636 )
2637     } else if (match_option(option, "-XX:+DisplayVMOutputToStderr", &tail)) {
2638       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, false);
2639       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, true);
2640     } else if (match_option(option, "-XX:+DisplayVMOutputToStdout", &tail)) {
2641       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, false);
2642       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, true);
2643     } else if (match_option(option, "-XX:+ExtendedDTraceProbes", &tail)) {
2644 #if defined(DTRACE_ENABLED)
2645       FLAG_SET_CMDLINE(bool, ExtendedDTraceProbes, true);
2646       FLAG_SET_CMDLINE(bool, DTraceMethodProbes, true);
2647       FLAG_SET_CMDLINE(bool, DTraceAllocProbes, true);
2648       FLAG_SET_CMDLINE(bool, DTraceMonitorProbes, true);
2649 #else // defined(DTRACE_ENABLED)
2650       jio_fprintf(defaultStream::error_stream(),
2651                   "ExtendedDTraceProbes flag is not applicable for this configuration\n");
2652       return JNI_EINVAL;
2653 #endif // defined(DTRACE_ENABLED)
2654 #ifdef ASSERT
2655     } else if (match_option(option, "-XX:+FullGCALot", &tail)) {
2656       FLAG_SET_CMDLINE(bool, FullGCALot, true);
2657       // disable scavenge before parallel mark-compact
2658       FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
2659 #endif
2660     } else if (match_option(option, "-XX:CMSParPromoteBlocksToClaim=", &tail)) {
2661       julong cms_blocks_to_claim = (julong)atol(tail);
2662       FLAG_SET_CMDLINE(uintx, CMSParPromoteBlocksToClaim, cms_blocks_to_claim);
2663       jio_fprintf(defaultStream::error_stream(),
2664         "Please use -XX:OldPLABSize in place of "
2665         "-XX:CMSParPromoteBlocksToClaim in the future\n");
2666     } else if (match_option(option, "-XX:ParCMSPromoteBlocksToClaim=", &tail)) {
2667       julong cms_blocks_to_claim = (julong)atol(tail);
2668       FLAG_SET_CMDLINE(uintx, CMSParPromoteBlocksToClaim, cms_blocks_to_claim);
2669       jio_fprintf(defaultStream::error_stream(),
2670         "Please use -XX:OldPLABSize in place of "
2671         "-XX:ParCMSPromoteBlocksToClaim in the future\n");
2672     } else if (match_option(option, "-XX:ParallelGCOldGenAllocBufferSize=", &tail)) {
2673       julong old_plab_size = 0;
2674       ArgsRange errcode = parse_memory_size(tail, &old_plab_size, 1);
2675       if (errcode != arg_in_range) {
2676         jio_fprintf(defaultStream::error_stream(),
2677                     "Invalid old PLAB size: %s\n", option->optionString);
2678         describe_range_error(errcode);
2679         return JNI_EINVAL;
2680       }
2681       FLAG_SET_CMDLINE(uintx, OldPLABSize, old_plab_size);
2682       jio_fprintf(defaultStream::error_stream(),
2683                   "Please use -XX:OldPLABSize in place of "
2684                   "-XX:ParallelGCOldGenAllocBufferSize in the future\n");
2685     } else if (match_option(option, "-XX:ParallelGCToSpaceAllocBufferSize=", &tail)) {
2686       julong young_plab_size = 0;
2687       ArgsRange errcode = parse_memory_size(tail, &young_plab_size, 1);
2688       if (errcode != arg_in_range) {
2689         jio_fprintf(defaultStream::error_stream(),
2690                     "Invalid young PLAB size: %s\n", option->optionString);
2691         describe_range_error(errcode);
2692         return JNI_EINVAL;
2693       }
2694       FLAG_SET_CMDLINE(uintx, YoungPLABSize, young_plab_size);
2695       jio_fprintf(defaultStream::error_stream(),
2696                   "Please use -XX:YoungPLABSize in place of "
2697                   "-XX:ParallelGCToSpaceAllocBufferSize in the future\n");
2698     } else if (match_option(option, "-XX:CMSMarkStackSize=", &tail) ||
2699                match_option(option, "-XX:G1MarkStackSize=", &tail)) {
2700       julong stack_size = 0;
2701       ArgsRange errcode = parse_memory_size(tail, &stack_size, 1);
2702       if (errcode != arg_in_range) {
2703         jio_fprintf(defaultStream::error_stream(),
2704                     "Invalid mark stack size: %s\n", option->optionString);
2705         describe_range_error(errcode);
2706         return JNI_EINVAL;
2707       }
2708       FLAG_SET_CMDLINE(uintx, MarkStackSize, stack_size);
2709     } else if (match_option(option, "-XX:CMSMarkStackSizeMax=", &tail)) {
2710       julong max_stack_size = 0;
2711       ArgsRange errcode = parse_memory_size(tail, &max_stack_size, 1);
2712       if (errcode != arg_in_range) {
2713         jio_fprintf(defaultStream::error_stream(),
2714                     "Invalid maximum mark stack size: %s\n",
2715                     option->optionString);
2716         describe_range_error(errcode);
2717         return JNI_EINVAL;
2718       }
2719       FLAG_SET_CMDLINE(uintx, MarkStackSizeMax, max_stack_size);
2720     } else if (match_option(option, "-XX:ParallelMarkingThreads=", &tail) ||
2721                match_option(option, "-XX:ParallelCMSThreads=", &tail)) {
2722       uintx conc_threads = 0;
2723       if (!parse_uintx(tail, &conc_threads, 1)) {
2724         jio_fprintf(defaultStream::error_stream(),
2725                     "Invalid concurrent threads: %s\n", option->optionString);
2726         return JNI_EINVAL;
2727       }
2728       FLAG_SET_CMDLINE(uintx, ConcGCThreads, conc_threads);
2729     } else if (match_option(option, "-XX:MaxDirectMemorySize=", &tail)) {
2730       julong max_direct_memory_size = 0;
2731       ArgsRange errcode = parse_memory_size(tail, &max_direct_memory_size, 0);
2732       if (errcode != arg_in_range) {
2733         jio_fprintf(defaultStream::error_stream(),
2734                     "Invalid maximum direct memory size: %s\n",
2735                     option->optionString);
2736         describe_range_error(errcode);
2737         return JNI_EINVAL;
2738       }
2739       FLAG_SET_CMDLINE(uintx, MaxDirectMemorySize, max_direct_memory_size);
2740     } else if (match_option(option, "-XX:", &tail)) { // -XX:xxxx
2741       // Skip -XX:Flags= since that case has already been handled
2742       if (strncmp(tail, "Flags=", strlen("Flags=")) != 0) {
2743         if (!process_argument(tail, args->ignoreUnrecognized, origin)) {
2744           return JNI_EINVAL;
2745         }
2746       }
2747     // Unknown option
2748     } else if (is_bad_option(option, args->ignoreUnrecognized)) {
2749       return JNI_ERR;
2750     }
2751   }
2752 
2753   // Change the default value for flags  which have different default values
2754   // when working with older JDKs.
2755   if (JDK_Version::current().compare_major(6) <= 0 &&
2756       FLAG_IS_DEFAULT(UseVMInterruptibleIO)) {
2757     FLAG_SET_DEFAULT(UseVMInterruptibleIO, true);
2758   }
2759 #ifdef LINUX
2760  if (JDK_Version::current().compare_major(6) <= 0 &&
2761       FLAG_IS_DEFAULT(UseLinuxPosixThreadCPUClocks)) {
2762     FLAG_SET_DEFAULT(UseLinuxPosixThreadCPUClocks, false);
2763   }
2764 #endif // LINUX
2765   return JNI_OK;
2766 }
2767 
2768 jint Arguments::finalize_vm_init_args(SysClassPath* scp_p, bool scp_assembly_required) {
2769   // This must be done after all -D arguments have been processed.
2770   scp_p->expand_endorsed();
2771 
2772   if (scp_assembly_required || scp_p->get_endorsed() != NULL) {
2773     // Assemble the bootclasspath elements into the final path.
2774     Arguments::set_sysclasspath(scp_p->combined_path());
2775   }
2776 
2777   // This must be done after all arguments have been processed.
2778   // java_compiler() true means set to "NONE" or empty.
2779   if (java_compiler() && !xdebug_mode()) {
2780     // For backwards compatibility, we switch to interpreted mode if
2781     // -Djava.compiler="NONE" or "" is specified AND "-Xdebug" was
2782     // not specified.
2783     set_mode_flags(_int);
2784   }
2785   if (CompileThreshold == 0) {
2786     set_mode_flags(_int);
2787   }
2788 
2789 #ifndef COMPILER2
2790   // Don't degrade server performance for footprint
2791   if (FLAG_IS_DEFAULT(UseLargePages) &&
2792       MaxHeapSize < LargePageHeapSizeThreshold) {
2793     // No need for large granularity pages w/small heaps.
2794     // Note that large pages are enabled/disabled for both the
2795     // Java heap and the code cache.
2796     FLAG_SET_DEFAULT(UseLargePages, false);
2797     SOLARIS_ONLY(FLAG_SET_DEFAULT(UseMPSS, false));
2798     SOLARIS_ONLY(FLAG_SET_DEFAULT(UseISM, false));
2799   }
2800 
2801   // Tiered compilation is undefined with C1.
2802   TieredCompilation = false;
2803 #else
2804   if (!FLAG_IS_DEFAULT(OptoLoopAlignment) && FLAG_IS_DEFAULT(MaxLoopPad)) {
2805     FLAG_SET_DEFAULT(MaxLoopPad, OptoLoopAlignment-1);
2806   }
2807 #endif
2808 
2809   // If we are running in a headless jre, force java.awt.headless property
2810   // to be true unless the property has already been set.
2811   // Also allow the OS environment variable JAVA_AWT_HEADLESS to set headless state.
2812   if (os::is_headless_jre()) {
2813     const char* headless = Arguments::get_property("java.awt.headless");
2814     if (headless == NULL) {
2815       char envbuffer[128];
2816       if (!os::getenv("JAVA_AWT_HEADLESS", envbuffer, sizeof(envbuffer))) {
2817         if (!add_property("java.awt.headless=true")) {
2818           return JNI_ENOMEM;
2819         }
2820       } else {
2821         char buffer[256];
2822         strcpy(buffer, "java.awt.headless=");
2823         strcat(buffer, envbuffer);
2824         if (!add_property(buffer)) {
2825           return JNI_ENOMEM;
2826         }
2827       }
2828     }
2829   }
2830 
2831   if (!check_vm_args_consistency()) {
2832     return JNI_ERR;
2833   }
2834 
2835   return JNI_OK;
2836 }
2837 
2838 jint Arguments::parse_java_options_environment_variable(SysClassPath* scp_p, bool* scp_assembly_required_p) {
2839   return parse_options_environment_variable("_JAVA_OPTIONS", scp_p,
2840                                             scp_assembly_required_p);
2841 }
2842 
2843 jint Arguments::parse_java_tool_options_environment_variable(SysClassPath* scp_p, bool* scp_assembly_required_p) {
2844   return parse_options_environment_variable("JAVA_TOOL_OPTIONS", scp_p,
2845                                             scp_assembly_required_p);
2846 }
2847 
2848 jint Arguments::parse_options_environment_variable(const char* name, SysClassPath* scp_p, bool* scp_assembly_required_p) {
2849   const int N_MAX_OPTIONS = 64;
2850   const int OPTION_BUFFER_SIZE = 1024;
2851   char buffer[OPTION_BUFFER_SIZE];
2852 
2853   // The variable will be ignored if it exceeds the length of the buffer.
2854   // Don't check this variable if user has special privileges
2855   // (e.g. unix su command).
2856   if (os::getenv(name, buffer, sizeof(buffer)) &&
2857       !os::have_special_privileges()) {
2858     JavaVMOption options[N_MAX_OPTIONS];      // Construct option array
2859     jio_fprintf(defaultStream::error_stream(),
2860                 "Picked up %s: %s\n", name, buffer);
2861     char* rd = buffer;                        // pointer to the input string (rd)
2862     int i;
2863     for (i = 0; i < N_MAX_OPTIONS;) {         // repeat for all options in the input string
2864       while (isspace(*rd)) rd++;              // skip whitespace
2865       if (*rd == 0) break;                    // we re done when the input string is read completely
2866 
2867       // The output, option string, overwrites the input string.
2868       // Because of quoting, the pointer to the option string (wrt) may lag the pointer to
2869       // input string (rd).
2870       char* wrt = rd;
2871 
2872       options[i++].optionString = wrt;        // Fill in option
2873       while (*rd != 0 && !isspace(*rd)) {     // unquoted strings terminate with a space or NULL
2874         if (*rd == '\'' || *rd == '"') {      // handle a quoted string
2875           int quote = *rd;                    // matching quote to look for
2876           rd++;                               // don't copy open quote
2877           while (*rd != quote) {              // include everything (even spaces) up until quote
2878             if (*rd == 0) {                   // string termination means unmatched string
2879               jio_fprintf(defaultStream::error_stream(),
2880                           "Unmatched quote in %s\n", name);
2881               return JNI_ERR;
2882             }
2883             *wrt++ = *rd++;                   // copy to option string
2884           }
2885           rd++;                               // don't copy close quote
2886         } else {
2887           *wrt++ = *rd++;                     // copy to option string
2888         }
2889       }
2890       // Need to check if we're done before writing a NULL,
2891       // because the write could be to the byte that rd is pointing to.
2892       if (*rd++ == 0) {
2893         *wrt = 0;
2894         break;
2895       }
2896       *wrt = 0;                               // Zero terminate option
2897     }
2898     // Construct JavaVMInitArgs structure and parse as if it was part of the command line
2899     JavaVMInitArgs vm_args;
2900     vm_args.version = JNI_VERSION_1_2;
2901     vm_args.options = options;
2902     vm_args.nOptions = i;
2903     vm_args.ignoreUnrecognized = IgnoreUnrecognizedVMOptions;
2904 
2905     if (PrintVMOptions) {
2906       const char* tail;
2907       for (int i = 0; i < vm_args.nOptions; i++) {
2908         const JavaVMOption *option = vm_args.options + i;
2909         if (match_option(option, "-XX:", &tail)) {
2910           logOption(tail);
2911         }
2912       }
2913     }
2914 
2915     return(parse_each_vm_init_arg(&vm_args, scp_p, scp_assembly_required_p, ENVIRON_VAR));
2916   }
2917   return JNI_OK;
2918 }
2919 
2920 void Arguments::set_shared_spaces_flags() {
2921   const bool must_share = DumpSharedSpaces || RequireSharedSpaces;
2922   const bool might_share = must_share || UseSharedSpaces;
2923 
2924   // CompressedOops cannot be used with CDS.  The offsets of oopmaps and
2925   // static fields are incorrect in the archive.  With some more clever
2926   // initialization, this restriction can probably be lifted.
2927   // ??? UseLargePages might be okay now
2928   const bool cannot_share = UseCompressedOops ||
2929                             (UseLargePages && FLAG_IS_CMDLINE(UseLargePages));
2930   if (cannot_share) {
2931     if (must_share) {
2932         warning("disabling large pages %s"
2933                 "because of %s", "" LP64_ONLY("and compressed oops "),
2934                 DumpSharedSpaces ? "-Xshare:dump" : "-Xshare:on");
2935         FLAG_SET_CMDLINE(bool, UseLargePages, false);
2936         LP64_ONLY(FLAG_SET_CMDLINE(bool, UseCompressedOops, false));
2937         LP64_ONLY(FLAG_SET_CMDLINE(bool, UseCompressedKlassPointers, false));
2938     } else {
2939       // Prefer compressed oops and large pages to class data sharing
2940       if (UseSharedSpaces && Verbose) {
2941         warning("turning off use of shared archive because of large pages%s",
2942                  "" LP64_ONLY(" and/or compressed oops"));
2943       }
2944       no_shared_spaces();
2945     }
2946   } else if (UseLargePages && might_share) {
2947     // Disable large pages to allow shared spaces.  This is sub-optimal, since
2948     // there may not even be a shared archive to use.
2949     FLAG_SET_DEFAULT(UseLargePages, false);
2950   }
2951 
2952   // Add 2M to any size for SharedReadOnlySize to get around the JPRT setting
2953   if (DumpSharedSpaces && !FLAG_IS_DEFAULT(SharedReadOnlySize)) {
2954     SharedReadOnlySize = 14*M;
2955   }
2956 
2957   if (DumpSharedSpaces) {
2958     if (RequireSharedSpaces) {
2959       warning("cannot dump shared archive while using shared archive");
2960     }
2961     UseSharedSpaces = false;
2962   }
2963 }
2964 
2965 // Disable options not supported in this release, with a warning if they
2966 // were explicitly requested on the command-line
2967 #define UNSUPPORTED_OPTION(opt, description)                    \
2968 do {                                                            \
2969   if (opt) {                                                    \
2970     if (FLAG_IS_CMDLINE(opt)) {                                 \
2971       warning(description " is disabled in this release.");     \
2972     }                                                           \
2973     FLAG_SET_DEFAULT(opt, false);                               \
2974   }                                                             \
2975 } while(0)
2976 
2977 // Parse entry point called from JNI_CreateJavaVM
2978 
2979 jint Arguments::parse(const JavaVMInitArgs* args) {
2980 
2981   // Sharing support
2982   // Construct the path to the archive
2983   char jvm_path[JVM_MAXPATHLEN];
2984   os::jvm_path(jvm_path, sizeof(jvm_path));
2985   char *end = strrchr(jvm_path, *os::file_separator());
2986   if (end != NULL) *end = '\0';
2987   char *shared_archive_path = NEW_C_HEAP_ARRAY(char, strlen(jvm_path) +
2988       strlen(os::file_separator()) + 20, mtInternal);
2989   if (shared_archive_path == NULL) return JNI_ENOMEM;
2990   strcpy(shared_archive_path, jvm_path);
2991   strcat(shared_archive_path, os::file_separator());
2992   strcat(shared_archive_path, "classes");
2993   DEBUG_ONLY(strcat(shared_archive_path, "_g");)
2994   strcat(shared_archive_path, ".jsa");
2995   SharedArchivePath = shared_archive_path;
2996 
2997   // Remaining part of option string
2998   const char* tail;
2999 
3000   // If flag "-XX:Flags=flags-file" is used it will be the first option to be processed.
3001   const char* hotspotrc = ".hotspotrc";
3002   bool settings_file_specified = false;
3003   bool needs_hotspotrc_warning = false;
3004 
3005   const char* flags_file;
3006   int index;
3007   for (index = 0; index < args->nOptions; index++) {
3008     const JavaVMOption *option = args->options + index;
3009     if (match_option(option, "-XX:Flags=", &tail)) {
3010       flags_file = tail;
3011       settings_file_specified = true;
3012     }
3013     if (match_option(option, "-XX:+PrintVMOptions", &tail)) {
3014       PrintVMOptions = true;
3015     }
3016     if (match_option(option, "-XX:-PrintVMOptions", &tail)) {
3017       PrintVMOptions = false;
3018     }
3019     if (match_option(option, "-XX:+IgnoreUnrecognizedVMOptions", &tail)) {
3020       IgnoreUnrecognizedVMOptions = true;
3021     }
3022     if (match_option(option, "-XX:-IgnoreUnrecognizedVMOptions", &tail)) {
3023       IgnoreUnrecognizedVMOptions = false;
3024     }
3025     if (match_option(option, "-XX:+PrintFlagsInitial", &tail)) {
3026       CommandLineFlags::printFlags(tty, false);
3027       vm_exit(0);
3028     }
3029     if (match_option(option, "-XX:NativeMemoryTracking", &tail)) {
3030       MemTracker::init_tracking_options(tail);
3031     }
3032 
3033 
3034 #ifndef PRODUCT
3035     if (match_option(option, "-XX:+PrintFlagsWithComments", &tail)) {
3036       CommandLineFlags::printFlags(tty, true);
3037       vm_exit(0);
3038     }
3039 #endif
3040   }
3041 
3042   if (IgnoreUnrecognizedVMOptions) {
3043     // uncast const to modify the flag args->ignoreUnrecognized
3044     *(jboolean*)(&args->ignoreUnrecognized) = true;
3045   }
3046 
3047   // Parse specified settings file
3048   if (settings_file_specified) {
3049     if (!process_settings_file(flags_file, true, args->ignoreUnrecognized)) {
3050       return JNI_EINVAL;
3051     }
3052   } else {
3053 #ifdef ASSERT
3054     // Parse default .hotspotrc settings file
3055     if (!process_settings_file(".hotspotrc", false, args->ignoreUnrecognized)) {
3056       return JNI_EINVAL;
3057     }
3058 #else
3059     struct stat buf;
3060     if (os::stat(hotspotrc, &buf) == 0) {
3061       needs_hotspotrc_warning = true;
3062     }
3063 #endif
3064   }
3065 
3066   if (PrintVMOptions) {
3067     for (index = 0; index < args->nOptions; index++) {
3068       const JavaVMOption *option = args->options + index;
3069       if (match_option(option, "-XX:", &tail)) {
3070         logOption(tail);
3071       }
3072     }
3073   }
3074 
3075   // Parse JavaVMInitArgs structure passed in, as well as JAVA_TOOL_OPTIONS and _JAVA_OPTIONS
3076   jint result = parse_vm_init_args(args);
3077   if (result != JNI_OK) {
3078     return result;
3079   }
3080 
3081   // Delay warning until here so that we've had a chance to process
3082   // the -XX:-PrintWarnings flag
3083   if (needs_hotspotrc_warning) {
3084     warning("%s file is present but has been ignored.  "
3085             "Run with -XX:Flags=%s to load the file.",
3086             hotspotrc, hotspotrc);
3087   }
3088 
3089 #if (defined JAVASE_EMBEDDED || defined ARM)
3090   UNSUPPORTED_OPTION(UseG1GC, "G1 GC");
3091 #endif
3092 
3093 #ifndef PRODUCT
3094   if (TraceBytecodesAt != 0) {
3095     TraceBytecodes = true;
3096   }
3097   if (CountCompiledCalls) {
3098     if (UseCounterDecay) {
3099       warning("UseCounterDecay disabled because CountCalls is set");
3100       UseCounterDecay = false;
3101     }
3102   }
3103 #endif // PRODUCT
3104 
3105   // JSR 292 is not supported before 1.7
3106   if (!JDK_Version::is_gte_jdk17x_version()) {
3107     if (EnableInvokeDynamic) {
3108       if (!FLAG_IS_DEFAULT(EnableInvokeDynamic)) {
3109         warning("JSR 292 is not supported before 1.7.  Disabling support.");
3110       }
3111       EnableInvokeDynamic = false;
3112     }
3113   }
3114 
3115   if (EnableInvokeDynamic && ScavengeRootsInCode == 0) {
3116     if (!FLAG_IS_DEFAULT(ScavengeRootsInCode)) {
3117       warning("forcing ScavengeRootsInCode non-zero because EnableInvokeDynamic is true");
3118     }
3119     ScavengeRootsInCode = 1;
3120   }
3121 
3122   if (PrintGCDetails) {
3123     // Turn on -verbose:gc options as well
3124     PrintGC = true;
3125   }
3126 
3127   if (!JDK_Version::is_gte_jdk18x_version()) {
3128     // To avoid changing the log format for 7 updates this flag is only
3129     // true by default in JDK8 and above.
3130     if (FLAG_IS_DEFAULT(PrintGCCause)) {
3131       FLAG_SET_DEFAULT(PrintGCCause, false);
3132     }
3133   }
3134 
3135   // Set object alignment values.
3136   set_object_alignment();
3137 
3138 #ifdef SERIALGC
3139   force_serial_gc();
3140 #endif // SERIALGC
3141 #ifdef KERNEL
3142   no_shared_spaces();
3143 #endif // KERNEL
3144 
3145   // Set flags based on ergonomics.
3146   set_ergonomics_flags();
3147 
3148   set_shared_spaces_flags();
3149 
3150   // Check the GC selections again.
3151   if (!check_gc_consistency()) {
3152     return JNI_EINVAL;
3153   }
3154 
3155   if (TieredCompilation) {
3156     set_tiered_flags();
3157   } else {
3158     // Check if the policy is valid. Policies 0 and 1 are valid for non-tiered setup.
3159     if (CompilationPolicyChoice >= 2) {
3160       vm_exit_during_initialization(
3161         "Incompatible compilation policy selected", NULL);
3162     }
3163   }
3164 
3165 #ifndef KERNEL
3166   // Set heap size based on available physical memory
3167   set_heap_size();
3168   // Set per-collector flags
3169   if (UseParallelGC || UseParallelOldGC) {
3170     set_parallel_gc_flags();
3171   } else if (UseConcMarkSweepGC) { // should be done before ParNew check below
3172     set_cms_and_parnew_gc_flags();
3173   } else if (UseParNewGC) {  // skipped if CMS is set above
3174     set_parnew_gc_flags();
3175   } else if (UseG1GC) {
3176     set_g1_gc_flags();
3177   }
3178 #endif // KERNEL
3179 
3180 #ifdef SERIALGC
3181   assert(verify_serial_gc_flags(), "SerialGC unset");
3182 #endif // SERIALGC
3183 
3184   // Set bytecode rewriting flags
3185   set_bytecode_flags();
3186 
3187   // Set flags if Aggressive optimization flags (-XX:+AggressiveOpts) enabled.
3188   set_aggressive_opts_flags();
3189 
3190   // Turn off biased locking for locking debug mode flags,
3191   // which are subtlely different from each other but neither works with
3192   // biased locking.
3193   if (UseHeavyMonitors
3194 #ifdef COMPILER1
3195       || !UseFastLocking
3196 #endif // COMPILER1
3197     ) {
3198     if (!FLAG_IS_DEFAULT(UseBiasedLocking) && UseBiasedLocking) {
3199       // flag set to true on command line; warn the user that they
3200       // can't enable biased locking here
3201       warning("Biased Locking is not supported with locking debug flags"
3202               "; ignoring UseBiasedLocking flag." );
3203     }
3204     UseBiasedLocking = false;
3205   }
3206 
3207 #ifdef CC_INTERP
3208   // Clear flags not supported by the C++ interpreter
3209   FLAG_SET_DEFAULT(ProfileInterpreter, false);
3210   FLAG_SET_DEFAULT(UseBiasedLocking, false);
3211   LP64_ONLY(FLAG_SET_DEFAULT(UseCompressedOops, false));
3212   LP64_ONLY(FLAG_SET_DEFAULT(UseCompressedKlassPointers, false));
3213 #endif // CC_INTERP
3214 
3215 #ifdef COMPILER2
3216   if (!UseBiasedLocking || EmitSync != 0) {
3217     UseOptoBiasInlining = false;
3218   }
3219   if (!EliminateLocks) {
3220     EliminateNestedLocks = false;
3221   }
3222 #endif
3223 
3224   if (PrintAssembly && FLAG_IS_DEFAULT(DebugNonSafepoints)) {
3225     warning("PrintAssembly is enabled; turning on DebugNonSafepoints to gain additional output");
3226     DebugNonSafepoints = true;
3227   }
3228 
3229 #ifndef PRODUCT
3230   if (CompileTheWorld) {
3231     // Force NmethodSweeper to sweep whole CodeCache each time.
3232     if (FLAG_IS_DEFAULT(NmethodSweepFraction)) {
3233       NmethodSweepFraction = 1;
3234     }
3235   }
3236 #endif
3237 
3238   if (PrintCommandLineFlags) {
3239     CommandLineFlags::printSetFlags(tty);
3240   }
3241 
3242   // Apply CPU specific policy for the BiasedLocking
3243   if (UseBiasedLocking) {
3244     if (!VM_Version::use_biased_locking() &&
3245         !(FLAG_IS_CMDLINE(UseBiasedLocking))) {
3246       UseBiasedLocking = false;
3247     }
3248   }
3249 
3250   // set PauseAtExit if the gamma launcher was used and a debugger is attached
3251   // but only if not already set on the commandline
3252   if (Arguments::created_by_gamma_launcher() && os::is_debugger_attached()) {
3253     bool set = false;
3254     CommandLineFlags::wasSetOnCmdline("PauseAtExit", &set);
3255     if (!set) {
3256       FLAG_SET_DEFAULT(PauseAtExit, true);
3257     }
3258   }
3259 
3260 #ifdef SPARC
3261   if (UseConcMarkSweepGC || UseG1GC) {
3262     // Issue a stern warning if the user has explicitly set
3263     // UseMemSetInBOT (it is known to cause issues), but allow
3264     // use for experimentation and debugging.
3265     if (VM_Version::is_sun4v() && UseMemSetInBOT) {
3266       assert(!FLAG_IS_DEFAULT(UseMemSetInBOT), "Error");
3267       warning("Experimental flag -XX:+UseMemSetInBOT is known to cause instability"
3268           " on sun4v; please understand that you are using at your own risk!");
3269     }
3270   }
3271 #endif // SPARC
3272 
3273   return JNI_OK;
3274 }
3275 
3276 int Arguments::PropertyList_count(SystemProperty* pl) {
3277   int count = 0;
3278   while(pl != NULL) {
3279     count++;
3280     pl = pl->next();
3281   }
3282   return count;
3283 }
3284 
3285 const char* Arguments::PropertyList_get_value(SystemProperty *pl, const char* key) {
3286   assert(key != NULL, "just checking");
3287   SystemProperty* prop;
3288   for (prop = pl; prop != NULL; prop = prop->next()) {
3289     if (strcmp(key, prop->key()) == 0) return prop->value();
3290   }
3291   return NULL;
3292 }
3293 
3294 const char* Arguments::PropertyList_get_key_at(SystemProperty *pl, int index) {
3295   int count = 0;
3296   const char* ret_val = NULL;
3297 
3298   while(pl != NULL) {
3299     if(count >= index) {
3300       ret_val = pl->key();
3301       break;
3302     }
3303     count++;
3304     pl = pl->next();
3305   }
3306 
3307   return ret_val;
3308 }
3309 
3310 char* Arguments::PropertyList_get_value_at(SystemProperty* pl, int index) {
3311   int count = 0;
3312   char* ret_val = NULL;
3313 
3314   while(pl != NULL) {
3315     if(count >= index) {
3316       ret_val = pl->value();
3317       break;
3318     }
3319     count++;
3320     pl = pl->next();
3321   }
3322 
3323   return ret_val;
3324 }
3325 
3326 void Arguments::PropertyList_add(SystemProperty** plist, SystemProperty *new_p) {
3327   SystemProperty* p = *plist;
3328   if (p == NULL) {
3329     *plist = new_p;
3330   } else {
3331     while (p->next() != NULL) {
3332       p = p->next();
3333     }
3334     p->set_next(new_p);
3335   }
3336 }
3337 
3338 void Arguments::PropertyList_add(SystemProperty** plist, const char* k, char* v) {
3339   if (plist == NULL)
3340     return;
3341 
3342   SystemProperty* new_p = new SystemProperty(k, v, true);
3343   PropertyList_add(plist, new_p);
3344 }
3345 
3346 // This add maintains unique property key in the list.
3347 void Arguments::PropertyList_unique_add(SystemProperty** plist, const char* k, char* v, jboolean append) {
3348   if (plist == NULL)
3349     return;
3350 
3351   // If property key exist then update with new value.
3352   SystemProperty* prop;
3353   for (prop = *plist; prop != NULL; prop = prop->next()) {
3354     if (strcmp(k, prop->key()) == 0) {
3355       if (append) {
3356         prop->append_value(v);
3357       } else {
3358         prop->set_value(v);
3359       }
3360       return;
3361     }
3362   }
3363 
3364   PropertyList_add(plist, k, v);
3365 }
3366 
3367 #ifdef KERNEL
3368 char *Arguments::get_kernel_properties() {
3369   // Find properties starting with kernel and append them to string
3370   // We need to find out how long they are first because the URL's that they
3371   // might point to could get long.
3372   int length = 0;
3373   SystemProperty* prop;
3374   for (prop = _system_properties; prop != NULL; prop = prop->next()) {
3375     if (strncmp(prop->key(), "kernel.", 7 ) == 0) {
3376       length += (strlen(prop->key()) + strlen(prop->value()) + 5);  // "-D ="
3377     }
3378   }
3379   // Add one for null terminator.
3380   char *props = AllocateHeap(length + 1, mtInternal);
3381   if (length != 0) {
3382     int pos = 0;
3383     for (prop = _system_properties; prop != NULL; prop = prop->next()) {
3384       if (strncmp(prop->key(), "kernel.", 7 ) == 0) {
3385         jio_snprintf(&props[pos], length-pos,
3386                      "-D%s=%s ", prop->key(), prop->value());
3387         pos = strlen(props);
3388       }
3389     }
3390   }
3391   // null terminate props in case of null
3392   props[length] = '\0';
3393   return props;
3394 }
3395 #endif // KERNEL
3396 
3397 // Copies src into buf, replacing "%%" with "%" and "%p" with pid
3398 // Returns true if all of the source pointed by src has been copied over to
3399 // the destination buffer pointed by buf. Otherwise, returns false.
3400 // Notes:
3401 // 1. If the length (buflen) of the destination buffer excluding the
3402 // NULL terminator character is not long enough for holding the expanded
3403 // pid characters, it also returns false instead of returning the partially
3404 // expanded one.
3405 // 2. The passed in "buflen" should be large enough to hold the null terminator.
3406 bool Arguments::copy_expand_pid(const char* src, size_t srclen,
3407                                 char* buf, size_t buflen) {
3408   const char* p = src;
3409   char* b = buf;
3410   const char* src_end = &src[srclen];
3411   char* buf_end = &buf[buflen - 1];
3412 
3413   while (p < src_end && b < buf_end) {
3414     if (*p == '%') {
3415       switch (*(++p)) {
3416       case '%':         // "%%" ==> "%"
3417         *b++ = *p++;
3418         break;
3419       case 'p':  {       //  "%p" ==> current process id
3420         // buf_end points to the character before the last character so
3421         // that we could write '\0' to the end of the buffer.
3422         size_t buf_sz = buf_end - b + 1;
3423         int ret = jio_snprintf(b, buf_sz, "%d", os::current_process_id());
3424 
3425         // if jio_snprintf fails or the buffer is not long enough to hold
3426         // the expanded pid, returns false.
3427         if (ret < 0 || ret >= (int)buf_sz) {
3428           return false;
3429         } else {
3430           b += ret;
3431           assert(*b == '\0', "fail in copy_expand_pid");
3432           if (p == src_end && b == buf_end + 1) {
3433             // reach the end of the buffer.
3434             return true;
3435           }
3436         }
3437         p++;
3438         break;
3439       }
3440       default :
3441         *b++ = '%';
3442       }
3443     } else {
3444       *b++ = *p++;
3445     }
3446   }
3447   *b = '\0';
3448   return (p == src_end); // return false if not all of the source was copied
3449 }