1 /*
   2  * Copyright (c) 1997, 2013, 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 "classfile/symbolTable.hpp"
  28 #include "compiler/compilerOracle.hpp"
  29 #include "memory/allocation.inline.hpp"
  30 #include "memory/cardTableRS.hpp"
  31 #include "memory/referenceProcessor.hpp"
  32 #include "memory/universe.inline.hpp"
  33 #include "oops/oop.inline.hpp"
  34 #include "prims/jvmtiExport.hpp"
  35 #include "runtime/arguments.hpp"
  36 #include "runtime/globals_extension.hpp"
  37 #include "runtime/java.hpp"
  38 #include "services/management.hpp"
  39 #include "services/memTracker.hpp"
  40 #include "utilities/defaultStream.hpp"
  41 #include "utilities/macros.hpp"
  42 #include "utilities/taskqueue.hpp"
  43 #ifdef TARGET_OS_FAMILY_linux
  44 # include "os_linux.inline.hpp"
  45 #endif
  46 #ifdef TARGET_OS_FAMILY_solaris
  47 # include "os_solaris.inline.hpp"
  48 #endif
  49 #ifdef TARGET_OS_FAMILY_windows
  50 # include "os_windows.inline.hpp"
  51 #endif
  52 #ifdef TARGET_OS_FAMILY_bsd
  53 # include "os_bsd.inline.hpp"
  54 #endif
  55 #if INCLUDE_ALL_GCS
  56 #include "gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.hpp"
  57 #endif // INCLUDE_ALL_GCS
  58 
  59 // Note: This is a special bug reporting site for the JVM
  60 #define DEFAULT_VENDOR_URL_BUG "http://bugreport.sun.com/bugreport/crash.jsp"
  61 #define DEFAULT_JAVA_LAUNCHER  "generic"
  62 
  63 char**  Arguments::_jvm_flags_array             = NULL;
  64 int     Arguments::_num_jvm_flags               = 0;
  65 char**  Arguments::_jvm_args_array              = NULL;
  66 int     Arguments::_num_jvm_args                = 0;
  67 char*  Arguments::_java_command                 = NULL;
  68 SystemProperty* Arguments::_system_properties   = NULL;
  69 const char*  Arguments::_gc_log_filename        = NULL;
  70 bool   Arguments::_has_profile                  = false;
  71 bool   Arguments::_has_alloc_profile            = false;
  72 uintx  Arguments::_min_heap_size                = 0;
  73 Arguments::Mode Arguments::_mode                = _mixed;
  74 bool   Arguments::_java_compiler                = false;
  75 bool   Arguments::_xdebug_mode                  = false;
  76 const char*  Arguments::_java_vendor_url_bug    = DEFAULT_VENDOR_URL_BUG;
  77 const char*  Arguments::_sun_java_launcher      = DEFAULT_JAVA_LAUNCHER;
  78 int    Arguments::_sun_java_launcher_pid        = -1;
  79 bool   Arguments::_created_by_gamma_launcher    = false;
  80 
  81 // These parameters are reset in method parse_vm_init_args(JavaVMInitArgs*)
  82 bool   Arguments::_AlwaysCompileLoopMethods     = AlwaysCompileLoopMethods;
  83 bool   Arguments::_UseOnStackReplacement        = UseOnStackReplacement;
  84 bool   Arguments::_BackgroundCompilation        = BackgroundCompilation;
  85 bool   Arguments::_ClipInlining                 = ClipInlining;
  86 
  87 char*  Arguments::SharedArchivePath             = NULL;
  88 
  89 AgentLibraryList Arguments::_libraryList;
  90 AgentLibraryList Arguments::_agentList;
  91 
  92 abort_hook_t     Arguments::_abort_hook         = NULL;
  93 exit_hook_t      Arguments::_exit_hook          = NULL;
  94 vfprintf_hook_t  Arguments::_vfprintf_hook      = NULL;
  95 
  96 
  97 SystemProperty *Arguments::_java_ext_dirs = NULL;
  98 SystemProperty *Arguments::_java_endorsed_dirs = NULL;
  99 SystemProperty *Arguments::_sun_boot_library_path = NULL;
 100 SystemProperty *Arguments::_java_library_path = NULL;
 101 SystemProperty *Arguments::_java_home = NULL;
 102 SystemProperty *Arguments::_java_class_path = NULL;
 103 SystemProperty *Arguments::_sun_boot_class_path = NULL;
 104 
 105 char* Arguments::_meta_index_path = NULL;
 106 char* Arguments::_meta_index_dir = NULL;
 107 
 108 // Check if head of 'option' matches 'name', and sets 'tail' remaining part of option string
 109 
 110 static bool match_option(const JavaVMOption *option, const char* name,
 111                          const char** tail) {
 112   int len = (int)strlen(name);
 113   if (strncmp(option->optionString, name, len) == 0) {
 114     *tail = option->optionString + len;
 115     return true;
 116   } else {
 117     return false;
 118   }
 119 }
 120 
 121 static void logOption(const char* opt) {
 122   if (PrintVMOptions) {
 123     jio_fprintf(defaultStream::output_stream(), "VM option '%s'\n", opt);
 124   }
 125 }
 126 
 127 // Process java launcher properties.
 128 void Arguments::process_sun_java_launcher_properties(JavaVMInitArgs* args) {
 129   // See if sun.java.launcher or sun.java.launcher.pid is defined.
 130   // Must do this before setting up other system properties,
 131   // as some of them may depend on launcher type.
 132   for (int index = 0; index < args->nOptions; index++) {
 133     const JavaVMOption* option = args->options + index;
 134     const char* tail;
 135 
 136     if (match_option(option, "-Dsun.java.launcher=", &tail)) {
 137       process_java_launcher_argument(tail, option->extraInfo);
 138       continue;
 139     }
 140     if (match_option(option, "-Dsun.java.launcher.pid=", &tail)) {
 141       _sun_java_launcher_pid = atoi(tail);
 142       continue;
 143     }
 144   }
 145 }
 146 
 147 // Initialize system properties key and value.
 148 void Arguments::init_system_properties() {
 149 
 150   PropertyList_add(&_system_properties, new SystemProperty("java.vm.specification.name",
 151                                                                  "Java Virtual Machine Specification",  false));
 152   PropertyList_add(&_system_properties, new SystemProperty("java.vm.version", VM_Version::vm_release(),  false));
 153   PropertyList_add(&_system_properties, new SystemProperty("java.vm.name", VM_Version::vm_name(),  false));
 154   PropertyList_add(&_system_properties, new SystemProperty("java.vm.info", VM_Version::vm_info_string(),  true));
 155 
 156   // following are JVMTI agent writeable properties.
 157   // Properties values are set to NULL and they are
 158   // os specific they are initialized in os::init_system_properties_values().
 159   _java_ext_dirs = new SystemProperty("java.ext.dirs", NULL,  true);
 160   _java_endorsed_dirs = new SystemProperty("java.endorsed.dirs", NULL,  true);
 161   _sun_boot_library_path = new SystemProperty("sun.boot.library.path", NULL,  true);
 162   _java_library_path = new SystemProperty("java.library.path", NULL,  true);
 163   _java_home =  new SystemProperty("java.home", NULL,  true);
 164   _sun_boot_class_path = new SystemProperty("sun.boot.class.path", NULL,  true);
 165 
 166   _java_class_path = new SystemProperty("java.class.path", "",  true);
 167 
 168   // Add to System Property list.
 169   PropertyList_add(&_system_properties, _java_ext_dirs);
 170   PropertyList_add(&_system_properties, _java_endorsed_dirs);
 171   PropertyList_add(&_system_properties, _sun_boot_library_path);
 172   PropertyList_add(&_system_properties, _java_library_path);
 173   PropertyList_add(&_system_properties, _java_home);
 174   PropertyList_add(&_system_properties, _java_class_path);
 175   PropertyList_add(&_system_properties, _sun_boot_class_path);
 176 
 177   // Set OS specific system properties values
 178   os::init_system_properties_values();
 179 }
 180 
 181 
 182   // Update/Initialize System properties after JDK version number is known
 183 void Arguments::init_version_specific_system_properties() {
 184   enum { bufsz = 16 };
 185   char buffer[bufsz];
 186   const char* spec_vendor = "Sun Microsystems Inc.";
 187   uint32_t spec_version = 0;
 188 
 189   if (JDK_Version::is_gte_jdk17x_version()) {
 190     spec_vendor = "Oracle Corporation";
 191     spec_version = JDK_Version::current().major_version();
 192   }
 193   jio_snprintf(buffer, bufsz, "1." UINT32_FORMAT, spec_version);
 194 
 195   PropertyList_add(&_system_properties,
 196       new SystemProperty("java.vm.specification.vendor",  spec_vendor, false));
 197   PropertyList_add(&_system_properties,
 198       new SystemProperty("java.vm.specification.version", buffer, false));
 199   PropertyList_add(&_system_properties,
 200       new SystemProperty("java.vm.vendor", VM_Version::vm_vendor(),  false));
 201 }
 202 
 203 /**
 204  * Provide a slightly more user-friendly way of eliminating -XX flags.
 205  * When a flag is eliminated, it can be added to this list in order to
 206  * continue accepting this flag on the command-line, while issuing a warning
 207  * and ignoring the value.  Once the JDK version reaches the 'accept_until'
 208  * limit, we flatly refuse to admit the existence of the flag.  This allows
 209  * a flag to die correctly over JDK releases using HSX.
 210  */
 211 typedef struct {
 212   const char* name;
 213   JDK_Version obsoleted_in; // when the flag went away
 214   JDK_Version accept_until; // which version to start denying the existence
 215 } ObsoleteFlag;
 216 
 217 static ObsoleteFlag obsolete_jvm_flags[] = {
 218   { "UseTrainGC",                    JDK_Version::jdk(5), JDK_Version::jdk(7) },
 219   { "UseSpecialLargeObjectHandling", JDK_Version::jdk(5), JDK_Version::jdk(7) },
 220   { "UseOversizedCarHandling",       JDK_Version::jdk(5), JDK_Version::jdk(7) },
 221   { "TraceCarAllocation",            JDK_Version::jdk(5), JDK_Version::jdk(7) },
 222   { "PrintTrainGCProcessingStats",   JDK_Version::jdk(5), JDK_Version::jdk(7) },
 223   { "LogOfCarSpaceSize",             JDK_Version::jdk(5), JDK_Version::jdk(7) },
 224   { "OversizedCarThreshold",         JDK_Version::jdk(5), JDK_Version::jdk(7) },
 225   { "MinTickInterval",               JDK_Version::jdk(5), JDK_Version::jdk(7) },
 226   { "DefaultTickInterval",           JDK_Version::jdk(5), JDK_Version::jdk(7) },
 227   { "MaxTickInterval",               JDK_Version::jdk(5), JDK_Version::jdk(7) },
 228   { "DelayTickAdjustment",           JDK_Version::jdk(5), JDK_Version::jdk(7) },
 229   { "ProcessingToTenuringRatio",     JDK_Version::jdk(5), JDK_Version::jdk(7) },
 230   { "MinTrainLength",                JDK_Version::jdk(5), JDK_Version::jdk(7) },
 231   { "AppendRatio",         JDK_Version::jdk_update(6,10), JDK_Version::jdk(7) },
 232   { "DefaultMaxRAM",       JDK_Version::jdk_update(6,18), JDK_Version::jdk(7) },
 233   { "DefaultInitialRAMFraction",
 234                            JDK_Version::jdk_update(6,18), JDK_Version::jdk(7) },
 235   { "UseDepthFirstScavengeOrder",
 236                            JDK_Version::jdk_update(6,22), JDK_Version::jdk(7) },
 237   { "HandlePromotionFailure",
 238                            JDK_Version::jdk_update(6,24), JDK_Version::jdk(8) },
 239   { "MaxLiveObjectEvacuationRatio",
 240                            JDK_Version::jdk_update(6,24), JDK_Version::jdk(8) },
 241   { "ForceSharedSpaces",   JDK_Version::jdk_update(6,25), JDK_Version::jdk(8) },
 242   { "UseParallelOldGCCompacting",
 243                            JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
 244   { "UseParallelDensePrefixUpdate",
 245                            JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
 246   { "UseParallelOldGCDensePrefix",
 247                            JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
 248   { "AllowTransitionalJSR292",       JDK_Version::jdk(7), JDK_Version::jdk(8) },
 249   { "UseCompressedStrings",          JDK_Version::jdk(7), JDK_Version::jdk(8) },
 250   { "CMSPermGenPrecleaningEnabled", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 251   { "CMSTriggerPermRatio", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 252   { "CMSInitiatingPermOccupancyFraction", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 253   { "AdaptivePermSizeWeight", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 254   { "PermGenPadding", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 255   { "PermMarkSweepDeadRatio", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 256   { "PermSize", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 257   { "MaxPermSize", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 258   { "MinPermHeapExpansion", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 259   { "MaxPermHeapExpansion", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 260   { "CMSRevisitStackSize",           JDK_Version::jdk(8), JDK_Version::jdk(9) },
 261   { "PrintRevisitStats",             JDK_Version::jdk(8), JDK_Version::jdk(9) },
 262   { "UseVectoredExceptions",         JDK_Version::jdk(8), JDK_Version::jdk(9) },
 263   { "UseSplitVerifier",              JDK_Version::jdk(8), JDK_Version::jdk(9) },
 264 #ifdef PRODUCT
 265   { "DesiredMethodLimit",
 266                            JDK_Version::jdk_update(7, 2), JDK_Version::jdk(8) },
 267 #endif // PRODUCT
 268   { NULL, JDK_Version(0), JDK_Version(0) }
 269 };
 270 
 271 // Returns true if the flag is obsolete and fits into the range specified
 272 // for being ignored.  In the case that the flag is ignored, the 'version'
 273 // value is filled in with the version number when the flag became
 274 // obsolete so that that value can be displayed to the user.
 275 bool Arguments::is_newly_obsolete(const char *s, JDK_Version* version) {
 276   int i = 0;
 277   assert(version != NULL, "Must provide a version buffer");
 278   while (obsolete_jvm_flags[i].name != NULL) {
 279     const ObsoleteFlag& flag_status = obsolete_jvm_flags[i];
 280     // <flag>=xxx form
 281     // [-|+]<flag> form
 282     if ((strncmp(flag_status.name, s, strlen(flag_status.name)) == 0) ||
 283         ((s[0] == '+' || s[0] == '-') &&
 284         (strncmp(flag_status.name, &s[1], strlen(flag_status.name)) == 0))) {
 285       if (JDK_Version::current().compare(flag_status.accept_until) == -1) {
 286           *version = flag_status.obsoleted_in;
 287           return true;
 288       }
 289     }
 290     i++;
 291   }
 292   return false;
 293 }
 294 
 295 // Constructs the system class path (aka boot class path) from the following
 296 // components, in order:
 297 //
 298 //     prefix           // from -Xbootclasspath/p:...
 299 //     endorsed         // the expansion of -Djava.endorsed.dirs=...
 300 //     base             // from os::get_system_properties() or -Xbootclasspath=
 301 //     suffix           // from -Xbootclasspath/a:...
 302 //
 303 // java.endorsed.dirs is a list of directories; any jar or zip files in the
 304 // directories are added to the sysclasspath just before the base.
 305 //
 306 // This could be AllStatic, but it isn't needed after argument processing is
 307 // complete.
 308 class SysClassPath: public StackObj {
 309 public:
 310   SysClassPath(const char* base);
 311   ~SysClassPath();
 312 
 313   inline void set_base(const char* base);
 314   inline void add_prefix(const char* prefix);
 315   inline void add_suffix_to_prefix(const char* suffix);
 316   inline void add_suffix(const char* suffix);
 317   inline void reset_path(const char* base);
 318 
 319   // Expand the jar/zip files in each directory listed by the java.endorsed.dirs
 320   // property.  Must be called after all command-line arguments have been
 321   // processed (in particular, -Djava.endorsed.dirs=...) and before calling
 322   // combined_path().
 323   void expand_endorsed();
 324 
 325   inline const char* get_base()     const { return _items[_scp_base]; }
 326   inline const char* get_prefix()   const { return _items[_scp_prefix]; }
 327   inline const char* get_suffix()   const { return _items[_scp_suffix]; }
 328   inline const char* get_endorsed() const { return _items[_scp_endorsed]; }
 329 
 330   // Combine all the components into a single c-heap-allocated string; caller
 331   // must free the string if/when no longer needed.
 332   char* combined_path();
 333 
 334 private:
 335   // Utility routines.
 336   static char* add_to_path(const char* path, const char* str, bool prepend);
 337   static char* add_jars_to_path(char* path, const char* directory);
 338 
 339   inline void reset_item_at(int index);
 340 
 341   // Array indices for the items that make up the sysclasspath.  All except the
 342   // base are allocated in the C heap and freed by this class.
 343   enum {
 344     _scp_prefix,        // from -Xbootclasspath/p:...
 345     _scp_endorsed,      // the expansion of -Djava.endorsed.dirs=...
 346     _scp_base,          // the default sysclasspath
 347     _scp_suffix,        // from -Xbootclasspath/a:...
 348     _scp_nitems         // the number of items, must be last.
 349   };
 350 
 351   const char* _items[_scp_nitems];
 352   DEBUG_ONLY(bool _expansion_done;)
 353 };
 354 
 355 SysClassPath::SysClassPath(const char* base) {
 356   memset(_items, 0, sizeof(_items));
 357   _items[_scp_base] = base;
 358   DEBUG_ONLY(_expansion_done = false;)
 359 }
 360 
 361 SysClassPath::~SysClassPath() {
 362   // Free everything except the base.
 363   for (int i = 0; i < _scp_nitems; ++i) {
 364     if (i != _scp_base) reset_item_at(i);
 365   }
 366   DEBUG_ONLY(_expansion_done = false;)
 367 }
 368 
 369 inline void SysClassPath::set_base(const char* base) {
 370   _items[_scp_base] = base;
 371 }
 372 
 373 inline void SysClassPath::add_prefix(const char* prefix) {
 374   _items[_scp_prefix] = add_to_path(_items[_scp_prefix], prefix, true);
 375 }
 376 
 377 inline void SysClassPath::add_suffix_to_prefix(const char* suffix) {
 378   _items[_scp_prefix] = add_to_path(_items[_scp_prefix], suffix, false);
 379 }
 380 
 381 inline void SysClassPath::add_suffix(const char* suffix) {
 382   _items[_scp_suffix] = add_to_path(_items[_scp_suffix], suffix, false);
 383 }
 384 
 385 inline void SysClassPath::reset_item_at(int index) {
 386   assert(index < _scp_nitems && index != _scp_base, "just checking");
 387   if (_items[index] != NULL) {
 388     FREE_C_HEAP_ARRAY(char, _items[index], mtInternal);
 389     _items[index] = NULL;
 390   }
 391 }
 392 
 393 inline void SysClassPath::reset_path(const char* base) {
 394   // Clear the prefix and suffix.
 395   reset_item_at(_scp_prefix);
 396   reset_item_at(_scp_suffix);
 397   set_base(base);
 398 }
 399 
 400 //------------------------------------------------------------------------------
 401 
 402 void SysClassPath::expand_endorsed() {
 403   assert(_items[_scp_endorsed] == NULL, "can only be called once.");
 404 
 405   const char* path = Arguments::get_property("java.endorsed.dirs");
 406   if (path == NULL) {
 407     path = Arguments::get_endorsed_dir();
 408     assert(path != NULL, "no default for java.endorsed.dirs");
 409   }
 410 
 411   char* expanded_path = NULL;
 412   const char separator = *os::path_separator();
 413   const char* const end = path + strlen(path);
 414   while (path < end) {
 415     const char* tmp_end = strchr(path, separator);
 416     if (tmp_end == NULL) {
 417       expanded_path = add_jars_to_path(expanded_path, path);
 418       path = end;
 419     } else {
 420       char* dirpath = NEW_C_HEAP_ARRAY(char, tmp_end - path + 1, mtInternal);
 421       memcpy(dirpath, path, tmp_end - path);
 422       dirpath[tmp_end - path] = '\0';
 423       expanded_path = add_jars_to_path(expanded_path, dirpath);
 424       FREE_C_HEAP_ARRAY(char, dirpath, mtInternal);
 425       path = tmp_end + 1;
 426     }
 427   }
 428   _items[_scp_endorsed] = expanded_path;
 429   DEBUG_ONLY(_expansion_done = true;)
 430 }
 431 
 432 // Combine the bootclasspath elements, some of which may be null, into a single
 433 // c-heap-allocated string.
 434 char* SysClassPath::combined_path() {
 435   assert(_items[_scp_base] != NULL, "empty default sysclasspath");
 436   assert(_expansion_done, "must call expand_endorsed() first.");
 437 
 438   size_t lengths[_scp_nitems];
 439   size_t total_len = 0;
 440 
 441   const char separator = *os::path_separator();
 442 
 443   // Get the lengths.
 444   int i;
 445   for (i = 0; i < _scp_nitems; ++i) {
 446     if (_items[i] != NULL) {
 447       lengths[i] = strlen(_items[i]);
 448       // Include space for the separator char (or a NULL for the last item).
 449       total_len += lengths[i] + 1;
 450     }
 451   }
 452   assert(total_len > 0, "empty sysclasspath not allowed");
 453 
 454   // Copy the _items to a single string.
 455   char* cp = NEW_C_HEAP_ARRAY(char, total_len, mtInternal);
 456   char* cp_tmp = cp;
 457   for (i = 0; i < _scp_nitems; ++i) {
 458     if (_items[i] != NULL) {
 459       memcpy(cp_tmp, _items[i], lengths[i]);
 460       cp_tmp += lengths[i];
 461       *cp_tmp++ = separator;
 462     }
 463   }
 464   *--cp_tmp = '\0';     // Replace the extra separator.
 465   return cp;
 466 }
 467 
 468 // Note:  path must be c-heap-allocated (or NULL); it is freed if non-null.
 469 char*
 470 SysClassPath::add_to_path(const char* path, const char* str, bool prepend) {
 471   char *cp;
 472 
 473   assert(str != NULL, "just checking");
 474   if (path == NULL) {
 475     size_t len = strlen(str) + 1;
 476     cp = NEW_C_HEAP_ARRAY(char, len, mtInternal);
 477     memcpy(cp, str, len);                       // copy the trailing null
 478   } else {
 479     const char separator = *os::path_separator();
 480     size_t old_len = strlen(path);
 481     size_t str_len = strlen(str);
 482     size_t len = old_len + str_len + 2;
 483 
 484     if (prepend) {
 485       cp = NEW_C_HEAP_ARRAY(char, len, mtInternal);
 486       char* cp_tmp = cp;
 487       memcpy(cp_tmp, str, str_len);
 488       cp_tmp += str_len;
 489       *cp_tmp = separator;
 490       memcpy(++cp_tmp, path, old_len + 1);      // copy the trailing null
 491       FREE_C_HEAP_ARRAY(char, path, mtInternal);
 492     } else {
 493       cp = REALLOC_C_HEAP_ARRAY(char, path, len, mtInternal);
 494       char* cp_tmp = cp + old_len;
 495       *cp_tmp = separator;
 496       memcpy(++cp_tmp, str, str_len + 1);       // copy the trailing null
 497     }
 498   }
 499   return cp;
 500 }
 501 
 502 // Scan the directory and append any jar or zip files found to path.
 503 // Note:  path must be c-heap-allocated (or NULL); it is freed if non-null.
 504 char* SysClassPath::add_jars_to_path(char* path, const char* directory) {
 505   DIR* dir = os::opendir(directory);
 506   if (dir == NULL) return path;
 507 
 508   char dir_sep[2] = { '\0', '\0' };
 509   size_t directory_len = strlen(directory);
 510   const char fileSep = *os::file_separator();
 511   if (directory[directory_len - 1] != fileSep) dir_sep[0] = fileSep;
 512 
 513   /* Scan the directory for jars/zips, appending them to path. */
 514   struct dirent *entry;
 515   char *dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory), mtInternal);
 516   while ((entry = os::readdir(dir, (dirent *) dbuf)) != NULL) {
 517     const char* name = entry->d_name;
 518     const char* ext = name + strlen(name) - 4;
 519     bool isJarOrZip = ext > name &&
 520       (os::file_name_strcmp(ext, ".jar") == 0 ||
 521        os::file_name_strcmp(ext, ".zip") == 0);
 522     if (isJarOrZip) {
 523       char* jarpath = NEW_C_HEAP_ARRAY(char, directory_len + 2 + strlen(name), mtInternal);
 524       sprintf(jarpath, "%s%s%s", directory, dir_sep, name);
 525       path = add_to_path(path, jarpath, false);
 526       FREE_C_HEAP_ARRAY(char, jarpath, mtInternal);
 527     }
 528   }
 529   FREE_C_HEAP_ARRAY(char, dbuf, mtInternal);
 530   os::closedir(dir);
 531   return path;
 532 }
 533 
 534 // Parses a memory size specification string.
 535 static bool atomull(const char *s, julong* result) {
 536   julong n = 0;
 537   int args_read = sscanf(s, JULONG_FORMAT, &n);
 538   if (args_read != 1) {
 539     return false;
 540   }
 541   while (*s != '\0' && isdigit(*s)) {
 542     s++;
 543   }
 544   // 4705540: illegal if more characters are found after the first non-digit
 545   if (strlen(s) > 1) {
 546     return false;
 547   }
 548   switch (*s) {
 549     case 'T': case 't':
 550       *result = n * G * K;
 551       // Check for overflow.
 552       if (*result/((julong)G * K) != n) return false;
 553       return true;
 554     case 'G': case 'g':
 555       *result = n * G;
 556       if (*result/G != n) return false;
 557       return true;
 558     case 'M': case 'm':
 559       *result = n * M;
 560       if (*result/M != n) return false;
 561       return true;
 562     case 'K': case 'k':
 563       *result = n * K;
 564       if (*result/K != n) return false;
 565       return true;
 566     case '\0':
 567       *result = n;
 568       return true;
 569     default:
 570       return false;
 571   }
 572 }
 573 
 574 Arguments::ArgsRange Arguments::check_memory_size(julong size, julong min_size) {
 575   if (size < min_size) return arg_too_small;
 576   // Check that size will fit in a size_t (only relevant on 32-bit)
 577   if (size > max_uintx) return arg_too_big;
 578   return arg_in_range;
 579 }
 580 
 581 // Describe an argument out of range error
 582 void Arguments::describe_range_error(ArgsRange errcode) {
 583   switch(errcode) {
 584   case arg_too_big:
 585     jio_fprintf(defaultStream::error_stream(),
 586                 "The specified size exceeds the maximum "
 587                 "representable size.\n");
 588     break;
 589   case arg_too_small:
 590   case arg_unreadable:
 591   case arg_in_range:
 592     // do nothing for now
 593     break;
 594   default:
 595     ShouldNotReachHere();
 596   }
 597 }
 598 
 599 static bool set_bool_flag(char* name, bool value, FlagValueOrigin origin) {
 600   return CommandLineFlags::boolAtPut(name, &value, origin);
 601 }
 602 
 603 static bool set_fp_numeric_flag(char* name, char* value, FlagValueOrigin origin) {
 604   double v;
 605   if (sscanf(value, "%lf", &v) != 1) {
 606     return false;
 607   }
 608 
 609   if (CommandLineFlags::doubleAtPut(name, &v, origin)) {
 610     return true;
 611   }
 612   return false;
 613 }
 614 
 615 static bool set_numeric_flag(char* name, char* value, FlagValueOrigin origin) {
 616   julong v;
 617   intx intx_v;
 618   bool is_neg = false;
 619   // Check the sign first since atomull() parses only unsigned values.
 620   if (*value == '-') {
 621     if (!CommandLineFlags::intxAt(name, &intx_v)) {
 622       return false;
 623     }
 624     value++;
 625     is_neg = true;
 626   }
 627   if (!atomull(value, &v)) {
 628     return false;
 629   }
 630   intx_v = (intx) v;
 631   if (is_neg) {
 632     intx_v = -intx_v;
 633   }
 634   if (CommandLineFlags::intxAtPut(name, &intx_v, origin)) {
 635     return true;
 636   }
 637   uintx uintx_v = (uintx) v;
 638   if (!is_neg && CommandLineFlags::uintxAtPut(name, &uintx_v, origin)) {
 639     return true;
 640   }
 641   uint64_t uint64_t_v = (uint64_t) v;
 642   if (!is_neg && CommandLineFlags::uint64_tAtPut(name, &uint64_t_v, origin)) {
 643     return true;
 644   }
 645   return false;
 646 }
 647 
 648 static bool set_string_flag(char* name, const char* value, FlagValueOrigin origin) {
 649   if (!CommandLineFlags::ccstrAtPut(name, &value, origin))  return false;
 650   // Contract:  CommandLineFlags always returns a pointer that needs freeing.
 651   FREE_C_HEAP_ARRAY(char, value, mtInternal);
 652   return true;
 653 }
 654 
 655 static bool append_to_string_flag(char* name, const char* new_value, FlagValueOrigin origin) {
 656   const char* old_value = "";
 657   if (!CommandLineFlags::ccstrAt(name, &old_value))  return false;
 658   size_t old_len = old_value != NULL ? strlen(old_value) : 0;
 659   size_t new_len = strlen(new_value);
 660   const char* value;
 661   char* free_this_too = NULL;
 662   if (old_len == 0) {
 663     value = new_value;
 664   } else if (new_len == 0) {
 665     value = old_value;
 666   } else {
 667     char* buf = NEW_C_HEAP_ARRAY(char, old_len + 1 + new_len + 1, mtInternal);
 668     // each new setting adds another LINE to the switch:
 669     sprintf(buf, "%s\n%s", old_value, new_value);
 670     value = buf;
 671     free_this_too = buf;
 672   }
 673   (void) CommandLineFlags::ccstrAtPut(name, &value, origin);
 674   // CommandLineFlags always returns a pointer that needs freeing.
 675   FREE_C_HEAP_ARRAY(char, value, mtInternal);
 676   if (free_this_too != NULL) {
 677     // CommandLineFlags made its own copy, so I must delete my own temp. buffer.
 678     FREE_C_HEAP_ARRAY(char, free_this_too, mtInternal);
 679   }
 680   return true;
 681 }
 682 
 683 bool Arguments::parse_argument(const char* arg, FlagValueOrigin origin) {
 684 
 685   // range of acceptable characters spelled out for portability reasons
 686 #define NAME_RANGE  "[abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_]"
 687 #define BUFLEN 255
 688   char name[BUFLEN+1];
 689   char dummy;
 690 
 691   if (sscanf(arg, "-%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
 692     return set_bool_flag(name, false, origin);
 693   }
 694   if (sscanf(arg, "+%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
 695     return set_bool_flag(name, true, origin);
 696   }
 697 
 698   char punct;
 699   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "%c", name, &punct) == 2 && punct == '=') {
 700     const char* value = strchr(arg, '=') + 1;
 701     Flag* flag = Flag::find_flag(name, strlen(name));
 702     if (flag != NULL && flag->is_ccstr()) {
 703       if (flag->ccstr_accumulates()) {
 704         return append_to_string_flag(name, value, origin);
 705       } else {
 706         if (value[0] == '\0') {
 707           value = NULL;
 708         }
 709         return set_string_flag(name, value, origin);
 710       }
 711     }
 712   }
 713 
 714   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE ":%c", name, &punct) == 2 && punct == '=') {
 715     const char* value = strchr(arg, '=') + 1;
 716     // -XX:Foo:=xxx will reset the string flag to the given value.
 717     if (value[0] == '\0') {
 718       value = NULL;
 719     }
 720     return set_string_flag(name, value, origin);
 721   }
 722 
 723 #define SIGNED_FP_NUMBER_RANGE "[-0123456789.]"
 724 #define SIGNED_NUMBER_RANGE    "[-0123456789]"
 725 #define        NUMBER_RANGE    "[0123456789]"
 726   char value[BUFLEN + 1];
 727   char value2[BUFLEN + 1];
 728   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_NUMBER_RANGE "." "%" XSTR(BUFLEN) NUMBER_RANGE "%c", name, value, value2, &dummy) == 3) {
 729     // Looks like a floating-point number -- try again with more lenient format string
 730     if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_FP_NUMBER_RANGE "%c", name, value, &dummy) == 2) {
 731       return set_fp_numeric_flag(name, value, origin);
 732     }
 733   }
 734 
 735 #define VALUE_RANGE "[-kmgtKMGT0123456789]"
 736   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) VALUE_RANGE "%c", name, value, &dummy) == 2) {
 737     return set_numeric_flag(name, value, origin);
 738   }
 739 
 740   return false;
 741 }
 742 
 743 void Arguments::add_string(char*** bldarray, int* count, const char* arg) {
 744   assert(bldarray != NULL, "illegal argument");
 745 
 746   if (arg == NULL) {
 747     return;
 748   }
 749 
 750   int index = *count;
 751 
 752   // expand the array and add arg to the last element
 753   (*count)++;
 754   if (*bldarray == NULL) {
 755     *bldarray = NEW_C_HEAP_ARRAY(char*, *count, mtInternal);
 756   } else {
 757     *bldarray = REALLOC_C_HEAP_ARRAY(char*, *bldarray, *count, mtInternal);
 758   }
 759   (*bldarray)[index] = strdup(arg);
 760 }
 761 
 762 void Arguments::build_jvm_args(const char* arg) {
 763   add_string(&_jvm_args_array, &_num_jvm_args, arg);
 764 }
 765 
 766 void Arguments::build_jvm_flags(const char* arg) {
 767   add_string(&_jvm_flags_array, &_num_jvm_flags, arg);
 768 }
 769 
 770 // utility function to return a string that concatenates all
 771 // strings in a given char** array
 772 const char* Arguments::build_resource_string(char** args, int count) {
 773   if (args == NULL || count == 0) {
 774     return NULL;
 775   }
 776   size_t length = strlen(args[0]) + 1; // add 1 for the null terminator
 777   for (int i = 1; i < count; i++) {
 778     length += strlen(args[i]) + 1; // add 1 for a space
 779   }
 780   char* s = NEW_RESOURCE_ARRAY(char, length);
 781   strcpy(s, args[0]);
 782   for (int j = 1; j < count; j++) {
 783     strcat(s, " ");
 784     strcat(s, args[j]);
 785   }
 786   return (const char*) s;
 787 }
 788 
 789 void Arguments::print_on(outputStream* st) {
 790   st->print_cr("VM Arguments:");
 791   if (num_jvm_flags() > 0) {
 792     st->print("jvm_flags: "); print_jvm_flags_on(st);
 793   }
 794   if (num_jvm_args() > 0) {
 795     st->print("jvm_args: "); print_jvm_args_on(st);
 796   }
 797   st->print_cr("java_command: %s", java_command() ? java_command() : "<unknown>");
 798   if (_java_class_path != NULL) {
 799     char* path = _java_class_path->value();
 800     st->print_cr("java_class_path (initial): %s", strlen(path) == 0 ? "<not set>" : path );
 801   }
 802   st->print_cr("Launcher Type: %s", _sun_java_launcher);
 803 }
 804 
 805 void Arguments::print_jvm_flags_on(outputStream* st) {
 806   if (_num_jvm_flags > 0) {
 807     for (int i=0; i < _num_jvm_flags; i++) {
 808       st->print("%s ", _jvm_flags_array[i]);
 809     }
 810     st->print_cr("");
 811   }
 812 }
 813 
 814 void Arguments::print_jvm_args_on(outputStream* st) {
 815   if (_num_jvm_args > 0) {
 816     for (int i=0; i < _num_jvm_args; i++) {
 817       st->print("%s ", _jvm_args_array[i]);
 818     }
 819     st->print_cr("");
 820   }
 821 }
 822 
 823 bool Arguments::process_argument(const char* arg,
 824     jboolean ignore_unrecognized, FlagValueOrigin origin) {
 825 
 826   JDK_Version since = JDK_Version();
 827 
 828   if (parse_argument(arg, origin) || ignore_unrecognized) {
 829     return true;
 830   }
 831 
 832   bool has_plus_minus = (*arg == '+' || *arg == '-');
 833   const char* const argname = has_plus_minus ? arg + 1 : arg;
 834   if (is_newly_obsolete(arg, &since)) {
 835     char version[256];
 836     since.to_string(version, sizeof(version));
 837     warning("ignoring option %s; support was removed in %s", argname, version);
 838     return true;
 839   }
 840 
 841   // For locked flags, report a custom error message if available.
 842   // Otherwise, report the standard unrecognized VM option.
 843 
 844   size_t arg_len;
 845   const char* equal_sign = strchr(argname, '=');
 846   if (equal_sign == NULL) {
 847     arg_len = strlen(argname);
 848   } else {
 849     arg_len = equal_sign - argname;
 850   }
 851 
 852   Flag* found_flag = Flag::find_flag((char*)argname, arg_len, true);
 853   if (found_flag != NULL) {
 854     char locked_message_buf[BUFLEN];
 855     found_flag->get_locked_message(locked_message_buf, BUFLEN);
 856     if (strlen(locked_message_buf) == 0) {
 857       if (found_flag->is_bool() && !has_plus_minus) {
 858         jio_fprintf(defaultStream::error_stream(),
 859           "Missing +/- setting for VM option '%s'\n", argname);
 860       } else if (!found_flag->is_bool() && has_plus_minus) {
 861         jio_fprintf(defaultStream::error_stream(),
 862           "Unexpected +/- setting in VM option '%s'\n", argname);
 863       } else {
 864         jio_fprintf(defaultStream::error_stream(),
 865           "Improperly specified VM option '%s'\n", argname);
 866       }
 867     } else {
 868       jio_fprintf(defaultStream::error_stream(), "%s", locked_message_buf);
 869     }
 870   } else {
 871     jio_fprintf(defaultStream::error_stream(),
 872                 "Unrecognized VM option '%s'\n", argname);
 873   }
 874 
 875   // allow for commandline "commenting out" options like -XX:#+Verbose
 876   return arg[0] == '#';
 877 }
 878 
 879 bool Arguments::process_settings_file(const char* file_name, bool should_exist, jboolean ignore_unrecognized) {
 880   FILE* stream = fopen(file_name, "rb");
 881   if (stream == NULL) {
 882     if (should_exist) {
 883       jio_fprintf(defaultStream::error_stream(),
 884                   "Could not open settings file %s\n", file_name);
 885       return false;
 886     } else {
 887       return true;
 888     }
 889   }
 890 
 891   char token[1024];
 892   int  pos = 0;
 893 
 894   bool in_white_space = true;
 895   bool in_comment     = false;
 896   bool in_quote       = false;
 897   char quote_c        = 0;
 898   bool result         = true;
 899 
 900   int c = getc(stream);
 901   while(c != EOF && pos < (int)(sizeof(token)-1)) {
 902     if (in_white_space) {
 903       if (in_comment) {
 904         if (c == '\n') in_comment = false;
 905       } else {
 906         if (c == '#') in_comment = true;
 907         else if (!isspace(c)) {
 908           in_white_space = false;
 909           token[pos++] = c;
 910         }
 911       }
 912     } else {
 913       if (c == '\n' || (!in_quote && isspace(c))) {
 914         // token ends at newline, or at unquoted whitespace
 915         // this allows a way to include spaces in string-valued options
 916         token[pos] = '\0';
 917         logOption(token);
 918         result &= process_argument(token, ignore_unrecognized, CONFIG_FILE);
 919         build_jvm_flags(token);
 920         pos = 0;
 921         in_white_space = true;
 922         in_quote = false;
 923       } else if (!in_quote && (c == '\'' || c == '"')) {
 924         in_quote = true;
 925         quote_c = c;
 926       } else if (in_quote && (c == quote_c)) {
 927         in_quote = false;
 928       } else {
 929         token[pos++] = c;
 930       }
 931     }
 932     c = getc(stream);
 933   }
 934   if (pos > 0) {
 935     token[pos] = '\0';
 936     result &= process_argument(token, ignore_unrecognized, CONFIG_FILE);
 937     build_jvm_flags(token);
 938   }
 939   fclose(stream);
 940   return result;
 941 }
 942 
 943 //=============================================================================================================
 944 // Parsing of properties (-D)
 945 
 946 const char* Arguments::get_property(const char* key) {
 947   return PropertyList_get_value(system_properties(), key);
 948 }
 949 
 950 bool Arguments::add_property(const char* prop) {
 951   const char* eq = strchr(prop, '=');
 952   char* key;
 953   // ns must be static--its address may be stored in a SystemProperty object.
 954   const static char ns[1] = {0};
 955   char* value = (char *)ns;
 956 
 957   size_t key_len = (eq == NULL) ? strlen(prop) : (eq - prop);
 958   key = AllocateHeap(key_len + 1, mtInternal);
 959   strncpy(key, prop, key_len);
 960   key[key_len] = '\0';
 961 
 962   if (eq != NULL) {
 963     size_t value_len = strlen(prop) - key_len - 1;
 964     value = AllocateHeap(value_len + 1, mtInternal);
 965     strncpy(value, &prop[key_len + 1], value_len + 1);
 966   }
 967 
 968   if (strcmp(key, "java.compiler") == 0) {
 969     process_java_compiler_argument(value);
 970     FreeHeap(key);
 971     if (eq != NULL) {
 972       FreeHeap(value);
 973     }
 974     return true;
 975   } else if (strcmp(key, "sun.java.command") == 0) {
 976     _java_command = value;
 977 
 978     // Record value in Arguments, but let it get passed to Java.
 979   } else if (strcmp(key, "sun.java.launcher.pid") == 0) {
 980     // launcher.pid property is private and is processed
 981     // in process_sun_java_launcher_properties();
 982     // the sun.java.launcher property is passed on to the java application
 983     FreeHeap(key);
 984     if (eq != NULL) {
 985       FreeHeap(value);
 986     }
 987     return true;
 988   } else if (strcmp(key, "java.vendor.url.bug") == 0) {
 989     // save it in _java_vendor_url_bug, so JVM fatal error handler can access
 990     // its value without going through the property list or making a Java call.
 991     _java_vendor_url_bug = value;
 992   } else if (strcmp(key, "sun.boot.library.path") == 0) {
 993     PropertyList_unique_add(&_system_properties, key, value, true);
 994     return true;
 995   }
 996   // Create new property and add at the end of the list
 997   PropertyList_unique_add(&_system_properties, key, value);
 998   return true;
 999 }
1000 
1001 //===========================================================================================================
1002 // Setting int/mixed/comp mode flags
1003 
1004 void Arguments::set_mode_flags(Mode mode) {
1005   // Set up default values for all flags.
1006   // If you add a flag to any of the branches below,
1007   // add a default value for it here.
1008   set_java_compiler(false);
1009   _mode                      = mode;
1010 
1011   // Ensure Agent_OnLoad has the correct initial values.
1012   // This may not be the final mode; mode may change later in onload phase.
1013   PropertyList_unique_add(&_system_properties, "java.vm.info",
1014                           (char*)VM_Version::vm_info_string(), false);
1015 
1016   UseInterpreter             = true;
1017   UseCompiler                = true;
1018   UseLoopCounter             = true;
1019 
1020 #ifndef ZERO
1021   // Turn these off for mixed and comp.  Leave them on for Zero.
1022   if (FLAG_IS_DEFAULT(UseFastAccessorMethods)) {
1023     UseFastAccessorMethods = (mode == _int);
1024   }
1025   if (FLAG_IS_DEFAULT(UseFastEmptyMethods)) {
1026     UseFastEmptyMethods = (mode == _int);
1027   }
1028 #endif
1029 
1030   // Default values may be platform/compiler dependent -
1031   // use the saved values
1032   ClipInlining               = Arguments::_ClipInlining;
1033   AlwaysCompileLoopMethods   = Arguments::_AlwaysCompileLoopMethods;
1034   UseOnStackReplacement      = Arguments::_UseOnStackReplacement;
1035   BackgroundCompilation      = Arguments::_BackgroundCompilation;
1036 
1037   // Change from defaults based on mode
1038   switch (mode) {
1039   default:
1040     ShouldNotReachHere();
1041     break;
1042   case _int:
1043     UseCompiler              = false;
1044     UseLoopCounter           = false;
1045     AlwaysCompileLoopMethods = false;
1046     UseOnStackReplacement    = false;
1047     break;
1048   case _mixed:
1049     // same as default
1050     break;
1051   case _comp:
1052     UseInterpreter           = false;
1053     BackgroundCompilation    = false;
1054     ClipInlining             = false;
1055     // Be much more aggressive in tiered mode with -Xcomp and exercise C2 more.
1056     // We will first compile a level 3 version (C1 with full profiling), then do one invocation of it and
1057     // compile a level 4 (C2) and then continue executing it.
1058     if (TieredCompilation) {
1059       Tier3InvokeNotifyFreqLog = 0;
1060       Tier4InvocationThreshold = 0;
1061     }
1062     break;
1063   }
1064 }
1065 
1066 // Conflict: required to use shared spaces (-Xshare:on), but
1067 // incompatible command line options were chosen.
1068 
1069 static void no_shared_spaces() {
1070   if (RequireSharedSpaces) {
1071     jio_fprintf(defaultStream::error_stream(),
1072       "Class data sharing is inconsistent with other specified options.\n");
1073     vm_exit_during_initialization("Unable to use shared archive.", NULL);
1074   } else {
1075     FLAG_SET_DEFAULT(UseSharedSpaces, false);
1076   }
1077 }
1078 
1079 void Arguments::set_tiered_flags() {
1080   // With tiered, set default policy to AdvancedThresholdPolicy, which is 3.
1081   if (FLAG_IS_DEFAULT(CompilationPolicyChoice)) {
1082     FLAG_SET_DEFAULT(CompilationPolicyChoice, 3);
1083   }
1084   if (CompilationPolicyChoice < 2) {
1085     vm_exit_during_initialization(
1086       "Incompatible compilation policy selected", NULL);
1087   }
1088   // Increase the code cache size - tiered compiles a lot more.
1089   if (FLAG_IS_DEFAULT(ReservedCodeCacheSize)) {
1090     FLAG_SET_DEFAULT(ReservedCodeCacheSize, ReservedCodeCacheSize * 5);
1091   }
1092 }
1093 
1094 #if INCLUDE_ALL_GCS
1095 static void disable_adaptive_size_policy(const char* collector_name) {
1096   if (UseAdaptiveSizePolicy) {
1097     if (FLAG_IS_CMDLINE(UseAdaptiveSizePolicy)) {
1098       warning("disabling UseAdaptiveSizePolicy; it is incompatible with %s.",
1099               collector_name);
1100     }
1101     FLAG_SET_DEFAULT(UseAdaptiveSizePolicy, false);
1102   }
1103 }
1104 
1105 void Arguments::set_parnew_gc_flags() {
1106   assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC && !UseG1GC,
1107          "control point invariant");
1108   assert(UseParNewGC, "Error");
1109 
1110   // Turn off AdaptiveSizePolicy for parnew until it is complete.
1111   disable_adaptive_size_policy("UseParNewGC");
1112 
1113   if (FLAG_IS_DEFAULT(ParallelGCThreads)) {
1114     FLAG_SET_DEFAULT(ParallelGCThreads, Abstract_VM_Version::parallel_worker_threads());
1115     assert(ParallelGCThreads > 0, "We should always have at least one thread by default");
1116   } else if (ParallelGCThreads == 0) {
1117     jio_fprintf(defaultStream::error_stream(),
1118         "The ParNew GC can not be combined with -XX:ParallelGCThreads=0\n");
1119     vm_exit(1);
1120   }
1121 
1122   // By default YoungPLABSize and OldPLABSize are set to 4096 and 1024 respectively,
1123   // these settings are default for Parallel Scavenger. For ParNew+Tenured configuration
1124   // we set them to 1024 and 1024.
1125   // See CR 6362902.
1126   if (FLAG_IS_DEFAULT(YoungPLABSize)) {
1127     FLAG_SET_DEFAULT(YoungPLABSize, (intx)1024);
1128   }
1129   if (FLAG_IS_DEFAULT(OldPLABSize)) {
1130     FLAG_SET_DEFAULT(OldPLABSize, (intx)1024);
1131   }
1132 
1133   // AlwaysTenure flag should make ParNew promote all at first collection.
1134   // See CR 6362902.
1135   if (AlwaysTenure) {
1136     FLAG_SET_CMDLINE(uintx, MaxTenuringThreshold, 0);
1137   }
1138   // When using compressed oops, we use local overflow stacks,
1139   // rather than using a global overflow list chained through
1140   // the klass word of the object's pre-image.
1141   if (UseCompressedOops && !ParGCUseLocalOverflow) {
1142     if (!FLAG_IS_DEFAULT(ParGCUseLocalOverflow)) {
1143       warning("Forcing +ParGCUseLocalOverflow: needed if using compressed references");
1144     }
1145     FLAG_SET_DEFAULT(ParGCUseLocalOverflow, true);
1146   }
1147   assert(ParGCUseLocalOverflow || !UseCompressedOops, "Error");
1148 }
1149 
1150 // Adjust some sizes to suit CMS and/or ParNew needs; these work well on
1151 // sparc/solaris for certain applications, but would gain from
1152 // further optimization and tuning efforts, and would almost
1153 // certainly gain from analysis of platform and environment.
1154 void Arguments::set_cms_and_parnew_gc_flags() {
1155   assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC, "Error");
1156   assert(UseConcMarkSweepGC, "CMS is expected to be on here");
1157 
1158   // If we are using CMS, we prefer to UseParNewGC,
1159   // unless explicitly forbidden.
1160   if (FLAG_IS_DEFAULT(UseParNewGC)) {
1161     FLAG_SET_ERGO(bool, UseParNewGC, true);
1162   }
1163 
1164   // Turn off AdaptiveSizePolicy by default for cms until it is complete.
1165   disable_adaptive_size_policy("UseConcMarkSweepGC");
1166 
1167   // In either case, adjust ParallelGCThreads and/or UseParNewGC
1168   // as needed.
1169   if (UseParNewGC) {
1170     set_parnew_gc_flags();
1171   }
1172 
1173   size_t max_heap = align_size_down(MaxHeapSize,
1174                                     CardTableRS::ct_max_alignment_constraint());
1175 
1176   // Now make adjustments for CMS
1177   intx   tenuring_default = (intx)6;
1178   size_t young_gen_per_worker = CMSYoungGenPerWorker;
1179 
1180   // Preferred young gen size for "short" pauses:
1181   // upper bound depends on # of threads and NewRatio.
1182   const uintx parallel_gc_threads =
1183     (ParallelGCThreads == 0 ? 1 : ParallelGCThreads);
1184   const size_t preferred_max_new_size_unaligned =
1185     MIN2(max_heap/(NewRatio+1), ScaleForWordSize(young_gen_per_worker * parallel_gc_threads));
1186   size_t preferred_max_new_size =
1187     align_size_up(preferred_max_new_size_unaligned, os::vm_page_size());
1188 
1189   // Unless explicitly requested otherwise, size young gen
1190   // for "short" pauses ~ CMSYoungGenPerWorker*ParallelGCThreads
1191 
1192   // If either MaxNewSize or NewRatio is set on the command line,
1193   // assume the user is trying to set the size of the young gen.
1194   if (FLAG_IS_DEFAULT(MaxNewSize) && FLAG_IS_DEFAULT(NewRatio)) {
1195 
1196     // Set MaxNewSize to our calculated preferred_max_new_size unless
1197     // NewSize was set on the command line and it is larger than
1198     // preferred_max_new_size.
1199     if (!FLAG_IS_DEFAULT(NewSize)) {   // NewSize explicitly set at command-line
1200       FLAG_SET_ERGO(uintx, MaxNewSize, MAX2(NewSize, preferred_max_new_size));
1201     } else {
1202       FLAG_SET_ERGO(uintx, MaxNewSize, preferred_max_new_size);
1203     }
1204     if (PrintGCDetails && Verbose) {
1205       // Too early to use gclog_or_tty
1206       tty->print_cr("CMS ergo set MaxNewSize: " SIZE_FORMAT, MaxNewSize);
1207     }
1208 
1209     // Code along this path potentially sets NewSize and OldSize
1210     if (PrintGCDetails && Verbose) {
1211       // Too early to use gclog_or_tty
1212       tty->print_cr("CMS set min_heap_size: " SIZE_FORMAT
1213            " initial_heap_size:  " SIZE_FORMAT
1214            " max_heap: " SIZE_FORMAT,
1215            min_heap_size(), InitialHeapSize, max_heap);
1216     }
1217     size_t min_new = preferred_max_new_size;
1218     if (FLAG_IS_CMDLINE(NewSize)) {
1219       min_new = NewSize;
1220     }
1221     if (max_heap > min_new && min_heap_size() > min_new) {
1222       // Unless explicitly requested otherwise, make young gen
1223       // at least min_new, and at most preferred_max_new_size.
1224       if (FLAG_IS_DEFAULT(NewSize)) {
1225         FLAG_SET_ERGO(uintx, NewSize, MAX2(NewSize, min_new));
1226         FLAG_SET_ERGO(uintx, NewSize, MIN2(preferred_max_new_size, NewSize));
1227         if (PrintGCDetails && Verbose) {
1228           // Too early to use gclog_or_tty
1229           tty->print_cr("CMS ergo set NewSize: " SIZE_FORMAT, NewSize);
1230         }
1231       }
1232       // Unless explicitly requested otherwise, size old gen
1233       // so it's NewRatio x of NewSize.
1234       if (FLAG_IS_DEFAULT(OldSize)) {
1235         if (max_heap > NewSize) {
1236           FLAG_SET_ERGO(uintx, OldSize, MIN2(NewRatio*NewSize, max_heap - NewSize));
1237           if (PrintGCDetails && Verbose) {
1238             // Too early to use gclog_or_tty
1239             tty->print_cr("CMS ergo set OldSize: " SIZE_FORMAT, OldSize);
1240           }
1241         }
1242       }
1243     }
1244   }
1245   // Unless explicitly requested otherwise, definitely
1246   // promote all objects surviving "tenuring_default" scavenges.
1247   if (FLAG_IS_DEFAULT(MaxTenuringThreshold) &&
1248       FLAG_IS_DEFAULT(SurvivorRatio)) {
1249     FLAG_SET_ERGO(uintx, MaxTenuringThreshold, tenuring_default);
1250   }
1251   // If we decided above (or user explicitly requested)
1252   // `promote all' (via MaxTenuringThreshold := 0),
1253   // prefer minuscule survivor spaces so as not to waste
1254   // space for (non-existent) survivors
1255   if (FLAG_IS_DEFAULT(SurvivorRatio) && MaxTenuringThreshold == 0) {
1256     FLAG_SET_ERGO(uintx, SurvivorRatio, MAX2((uintx)1024, SurvivorRatio));
1257   }
1258   // If OldPLABSize is set and CMSParPromoteBlocksToClaim is not,
1259   // set CMSParPromoteBlocksToClaim equal to OldPLABSize.
1260   // This is done in order to make ParNew+CMS configuration to work
1261   // with YoungPLABSize and OldPLABSize options.
1262   // See CR 6362902.
1263   if (!FLAG_IS_DEFAULT(OldPLABSize)) {
1264     if (FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim)) {
1265       // OldPLABSize is not the default value but CMSParPromoteBlocksToClaim
1266       // is.  In this situtation let CMSParPromoteBlocksToClaim follow
1267       // the value (either from the command line or ergonomics) of
1268       // OldPLABSize.  Following OldPLABSize is an ergonomics decision.
1269       FLAG_SET_ERGO(uintx, CMSParPromoteBlocksToClaim, OldPLABSize);
1270     } else {
1271       // OldPLABSize and CMSParPromoteBlocksToClaim are both set.
1272       // CMSParPromoteBlocksToClaim is a collector-specific flag, so
1273       // we'll let it to take precedence.
1274       jio_fprintf(defaultStream::error_stream(),
1275                   "Both OldPLABSize and CMSParPromoteBlocksToClaim"
1276                   " options are specified for the CMS collector."
1277                   " CMSParPromoteBlocksToClaim will take precedence.\n");
1278     }
1279   }
1280   if (!FLAG_IS_DEFAULT(ResizeOldPLAB) && !ResizeOldPLAB) {
1281     // OldPLAB sizing manually turned off: Use a larger default setting,
1282     // unless it was manually specified. This is because a too-low value
1283     // will slow down scavenges.
1284     if (FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim)) {
1285       FLAG_SET_ERGO(uintx, CMSParPromoteBlocksToClaim, 50); // default value before 6631166
1286     }
1287   }
1288   // Overwrite OldPLABSize which is the variable we will internally use everywhere.
1289   FLAG_SET_ERGO(uintx, OldPLABSize, CMSParPromoteBlocksToClaim);
1290   // If either of the static initialization defaults have changed, note this
1291   // modification.
1292   if (!FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim) || !FLAG_IS_DEFAULT(OldPLABWeight)) {
1293     CFLS_LAB::modify_initialization(OldPLABSize, OldPLABWeight);
1294   }
1295   if (PrintGCDetails && Verbose) {
1296     tty->print_cr("MarkStackSize: %uk  MarkStackSizeMax: %uk",
1297       MarkStackSize / K, MarkStackSizeMax / K);
1298     tty->print_cr("ConcGCThreads: %u", ConcGCThreads);
1299   }
1300 }
1301 #endif // INCLUDE_ALL_GCS
1302 
1303 void set_object_alignment() {
1304   // Object alignment.
1305   assert(is_power_of_2(ObjectAlignmentInBytes), "ObjectAlignmentInBytes must be power of 2");
1306   MinObjAlignmentInBytes     = ObjectAlignmentInBytes;
1307   assert(MinObjAlignmentInBytes >= HeapWordsPerLong * HeapWordSize, "ObjectAlignmentInBytes value is too small");
1308   MinObjAlignment            = MinObjAlignmentInBytes / HeapWordSize;
1309   assert(MinObjAlignmentInBytes == MinObjAlignment * HeapWordSize, "ObjectAlignmentInBytes value is incorrect");
1310   MinObjAlignmentInBytesMask = MinObjAlignmentInBytes - 1;
1311 
1312   LogMinObjAlignmentInBytes  = exact_log2(ObjectAlignmentInBytes);
1313   LogMinObjAlignment         = LogMinObjAlignmentInBytes - LogHeapWordSize;
1314 
1315   // Oop encoding heap max
1316   OopEncodingHeapMax = (uint64_t(max_juint) + 1) << LogMinObjAlignmentInBytes;
1317 
1318 #if INCLUDE_ALL_GCS
1319   // Set CMS global values
1320   CompactibleFreeListSpace::set_cms_values();
1321 #endif // INCLUDE_ALL_GCS
1322 }
1323 
1324 bool verify_object_alignment() {
1325   // Object alignment.
1326   if (!is_power_of_2(ObjectAlignmentInBytes)) {
1327     jio_fprintf(defaultStream::error_stream(),
1328                 "error: ObjectAlignmentInBytes=%d must be power of 2\n",
1329                 (int)ObjectAlignmentInBytes);
1330     return false;
1331   }
1332   if ((int)ObjectAlignmentInBytes < BytesPerLong) {
1333     jio_fprintf(defaultStream::error_stream(),
1334                 "error: ObjectAlignmentInBytes=%d must be greater or equal %d\n",
1335                 (int)ObjectAlignmentInBytes, BytesPerLong);
1336     return false;
1337   }
1338   // It does not make sense to have big object alignment
1339   // since a space lost due to alignment will be greater
1340   // then a saved space from compressed oops.
1341   if ((int)ObjectAlignmentInBytes > 256) {
1342     jio_fprintf(defaultStream::error_stream(),
1343                 "error: ObjectAlignmentInBytes=%d must not be greater than 256\n",
1344                 (int)ObjectAlignmentInBytes);
1345     return false;
1346   }
1347   // In case page size is very small.
1348   if ((int)ObjectAlignmentInBytes >= os::vm_page_size()) {
1349     jio_fprintf(defaultStream::error_stream(),
1350                 "error: ObjectAlignmentInBytes=%d must be less than page size %d\n",
1351                 (int)ObjectAlignmentInBytes, os::vm_page_size());
1352     return false;
1353   }
1354   return true;
1355 }
1356 
1357 inline uintx max_heap_for_compressed_oops() {
1358   // Avoid sign flip.
1359   if (OopEncodingHeapMax < ClassMetaspaceSize + os::vm_page_size()) {
1360     return 0;
1361   }
1362   LP64_ONLY(return OopEncodingHeapMax - ClassMetaspaceSize - os::vm_page_size());
1363   NOT_LP64(ShouldNotReachHere(); return 0);
1364 }
1365 
1366 bool Arguments::should_auto_select_low_pause_collector() {
1367   if (UseAutoGCSelectPolicy &&
1368       !FLAG_IS_DEFAULT(MaxGCPauseMillis) &&
1369       (MaxGCPauseMillis <= AutoGCSelectPauseMillis)) {
1370     if (PrintGCDetails) {
1371       // Cannot use gclog_or_tty yet.
1372       tty->print_cr("Automatic selection of the low pause collector"
1373        " based on pause goal of %d (ms)", MaxGCPauseMillis);
1374     }
1375     return true;
1376   }
1377   return false;
1378 }
1379 
1380 void Arguments::set_use_compressed_oops() {
1381 #ifndef ZERO
1382 #ifdef _LP64
1383   // MaxHeapSize is not set up properly at this point, but
1384   // the only value that can override MaxHeapSize if we are
1385   // to use UseCompressedOops is InitialHeapSize.
1386   size_t max_heap_size = MAX2(MaxHeapSize, InitialHeapSize);
1387 
1388   if (max_heap_size <= max_heap_for_compressed_oops()) {
1389 #if !defined(COMPILER1) || defined(TIERED)
1390     if (FLAG_IS_DEFAULT(UseCompressedOops)) {
1391       FLAG_SET_ERGO(bool, UseCompressedOops, true);
1392     }
1393 #endif
1394 #ifdef _WIN64
1395     if (UseLargePages && UseCompressedOops) {
1396       // Cannot allocate guard pages for implicit checks in indexed addressing
1397       // mode, when large pages are specified on windows.
1398       // This flag could be switched ON if narrow oop base address is set to 0,
1399       // see code in Universe::initialize_heap().
1400       Universe::set_narrow_oop_use_implicit_null_checks(false);
1401     }
1402 #endif //  _WIN64
1403   } else {
1404     if (UseCompressedOops && !FLAG_IS_DEFAULT(UseCompressedOops)) {
1405       warning("Max heap size too large for Compressed Oops");
1406       FLAG_SET_DEFAULT(UseCompressedOops, false);
1407       FLAG_SET_DEFAULT(UseCompressedKlassPointers, false);
1408     }
1409   }
1410 #endif // _LP64
1411 #endif // ZERO
1412 }
1413 
1414 void Arguments::set_ergonomics_flags() {
1415 
1416   if (os::is_server_class_machine()) {
1417     // If no other collector is requested explicitly,
1418     // let the VM select the collector based on
1419     // machine class and automatic selection policy.
1420     if (!UseSerialGC &&
1421         !UseConcMarkSweepGC &&
1422         !UseG1GC &&
1423         !UseParNewGC &&
1424         FLAG_IS_DEFAULT(UseParallelGC)) {
1425       if (should_auto_select_low_pause_collector()) {
1426         FLAG_SET_ERGO(bool, UseConcMarkSweepGC, true);
1427       } else {
1428         FLAG_SET_ERGO(bool, UseParallelGC, true);
1429       }
1430     }
1431     // Shared spaces work fine with other GCs but causes bytecode rewriting
1432     // to be disabled, which hurts interpreter performance and decreases
1433     // server performance.   On server class machines, keep the default
1434     // off unless it is asked for.  Future work: either add bytecode rewriting
1435     // at link time, or rewrite bytecodes in non-shared methods.
1436     if (!DumpSharedSpaces && !RequireSharedSpaces) {
1437       no_shared_spaces();
1438     }
1439   }
1440 
1441 #ifndef ZERO
1442 #ifdef _LP64
1443   set_use_compressed_oops();
1444   // UseCompressedOops must be on for UseCompressedKlassPointers to be on.
1445   if (!UseCompressedOops) {
1446     if (UseCompressedKlassPointers) {
1447       warning("UseCompressedKlassPointers requires UseCompressedOops");
1448     }
1449     FLAG_SET_DEFAULT(UseCompressedKlassPointers, false);
1450   } else {
1451     // Turn on UseCompressedKlassPointers too
1452     if (FLAG_IS_DEFAULT(UseCompressedKlassPointers)) {
1453       FLAG_SET_ERGO(bool, UseCompressedKlassPointers, true);
1454     }
1455     // Set the ClassMetaspaceSize to something that will not need to be
1456     // expanded, since it cannot be expanded.
1457     if (UseCompressedKlassPointers) {
1458       if (ClassMetaspaceSize > KlassEncodingMetaspaceMax) {
1459         warning("Class metaspace size is too large for UseCompressedKlassPointers");
1460         FLAG_SET_DEFAULT(UseCompressedKlassPointers, false);
1461       } else if (FLAG_IS_DEFAULT(ClassMetaspaceSize)) {
1462         // 100,000 classes seems like a good size, so 100M assumes around 1K
1463         // per klass.   The vtable and oopMap is embedded so we don't have a fixed
1464         // size per klass.   Eventually, this will be parameterized because it
1465         // would also be useful to determine the optimal size of the
1466         // systemDictionary.
1467         FLAG_SET_ERGO(uintx, ClassMetaspaceSize, 100*M);
1468       }
1469     }
1470   }
1471   // Also checks that certain machines are slower with compressed oops
1472   // in vm_version initialization code.
1473 #endif // _LP64
1474 #endif // !ZERO
1475 }
1476 
1477 void Arguments::set_parallel_gc_flags() {
1478   assert(UseParallelGC || UseParallelOldGC, "Error");
1479   // Enable ParallelOld unless it was explicitly disabled (cmd line or rc file).
1480   if (FLAG_IS_DEFAULT(UseParallelOldGC)) {
1481     FLAG_SET_DEFAULT(UseParallelOldGC, true);
1482   }
1483   FLAG_SET_DEFAULT(UseParallelGC, true);
1484 
1485   // If no heap maximum was requested explicitly, use some reasonable fraction
1486   // of the physical memory, up to a maximum of 1GB.
1487   FLAG_SET_DEFAULT(ParallelGCThreads,
1488                    Abstract_VM_Version::parallel_worker_threads());
1489   if (ParallelGCThreads == 0) {
1490     jio_fprintf(defaultStream::error_stream(),
1491         "The Parallel GC can not be combined with -XX:ParallelGCThreads=0\n");
1492     vm_exit(1);
1493   }
1494 
1495 
1496   // If InitialSurvivorRatio or MinSurvivorRatio were not specified, but the
1497   // SurvivorRatio has been set, reset their default values to SurvivorRatio +
1498   // 2.  By doing this we make SurvivorRatio also work for Parallel Scavenger.
1499   // See CR 6362902 for details.
1500   if (!FLAG_IS_DEFAULT(SurvivorRatio)) {
1501     if (FLAG_IS_DEFAULT(InitialSurvivorRatio)) {
1502        FLAG_SET_DEFAULT(InitialSurvivorRatio, SurvivorRatio + 2);
1503     }
1504     if (FLAG_IS_DEFAULT(MinSurvivorRatio)) {
1505       FLAG_SET_DEFAULT(MinSurvivorRatio, SurvivorRatio + 2);
1506     }
1507   }
1508 
1509   if (UseParallelOldGC) {
1510     // Par compact uses lower default values since they are treated as
1511     // minimums.  These are different defaults because of the different
1512     // interpretation and are not ergonomically set.
1513     if (FLAG_IS_DEFAULT(MarkSweepDeadRatio)) {
1514       FLAG_SET_DEFAULT(MarkSweepDeadRatio, 1);
1515     }
1516   }
1517 }
1518 
1519 void Arguments::set_g1_gc_flags() {
1520   assert(UseG1GC, "Error");
1521 #ifdef COMPILER1
1522   FastTLABRefill = false;
1523 #endif
1524   FLAG_SET_DEFAULT(ParallelGCThreads,
1525                      Abstract_VM_Version::parallel_worker_threads());
1526   if (ParallelGCThreads == 0) {
1527     FLAG_SET_DEFAULT(ParallelGCThreads,
1528                      Abstract_VM_Version::parallel_worker_threads());
1529   }
1530 
1531   // MarkStackSize will be set (if it hasn't been set by the user)
1532   // when concurrent marking is initialized.
1533   // Its value will be based upon the number of parallel marking threads.
1534   // But we do set the maximum mark stack size here.
1535   if (FLAG_IS_DEFAULT(MarkStackSizeMax)) {
1536     FLAG_SET_DEFAULT(MarkStackSizeMax, 128 * TASKQUEUE_SIZE);
1537   }
1538 
1539   if (FLAG_IS_DEFAULT(GCTimeRatio) || GCTimeRatio == 0) {
1540     // In G1, we want the default GC overhead goal to be higher than
1541     // say in PS. So we set it here to 10%. Otherwise the heap might
1542     // be expanded more aggressively than we would like it to. In
1543     // fact, even 10% seems to not be high enough in some cases
1544     // (especially small GC stress tests that the main thing they do
1545     // is allocation). We might consider increase it further.
1546     FLAG_SET_DEFAULT(GCTimeRatio, 9);
1547   }
1548 
1549   if (PrintGCDetails && Verbose) {
1550     tty->print_cr("MarkStackSize: %uk  MarkStackSizeMax: %uk",
1551       MarkStackSize / K, MarkStackSizeMax / K);
1552     tty->print_cr("ConcGCThreads: %u", ConcGCThreads);
1553   }
1554 }
1555 
1556 julong Arguments::limit_by_allocatable_memory(julong limit) {
1557   julong max_allocatable;
1558   julong result = limit;
1559   if (os::has_allocatable_memory_limit(&max_allocatable)) {
1560     result = MIN2(result, max_allocatable / MaxVirtMemFraction);
1561   }
1562   return result;
1563 }
1564 
1565 void Arguments::set_heap_size() {
1566   if (!FLAG_IS_DEFAULT(DefaultMaxRAMFraction)) {
1567     // Deprecated flag
1568     FLAG_SET_CMDLINE(uintx, MaxRAMFraction, DefaultMaxRAMFraction);
1569   }
1570 
1571   const julong phys_mem =
1572     FLAG_IS_DEFAULT(MaxRAM) ? MIN2(os::physical_memory(), (julong)MaxRAM)
1573                             : (julong)MaxRAM;
1574 
1575   // If the maximum heap size has not been set with -Xmx,
1576   // then set it as fraction of the size of physical memory,
1577   // respecting the maximum and minimum sizes of the heap.
1578   if (FLAG_IS_DEFAULT(MaxHeapSize)) {
1579     julong reasonable_max = phys_mem / MaxRAMFraction;
1580 
1581     if (phys_mem <= MaxHeapSize * MinRAMFraction) {
1582       // Small physical memory, so use a minimum fraction of it for the heap
1583       reasonable_max = phys_mem / MinRAMFraction;
1584     } else {
1585       // Not-small physical memory, so require a heap at least
1586       // as large as MaxHeapSize
1587       reasonable_max = MAX2(reasonable_max, (julong)MaxHeapSize);
1588     }
1589     if (!FLAG_IS_DEFAULT(ErgoHeapSizeLimit) && ErgoHeapSizeLimit != 0) {
1590       // Limit the heap size to ErgoHeapSizeLimit
1591       reasonable_max = MIN2(reasonable_max, (julong)ErgoHeapSizeLimit);
1592     }
1593     if (UseCompressedOops) {
1594       // Limit the heap size to the maximum possible when using compressed oops
1595       julong max_coop_heap = (julong)max_heap_for_compressed_oops();
1596       if (HeapBaseMinAddress + MaxHeapSize < max_coop_heap) {
1597         // Heap should be above HeapBaseMinAddress to get zero based compressed oops
1598         // but it should be not less than default MaxHeapSize.
1599         max_coop_heap -= HeapBaseMinAddress;
1600       }
1601       reasonable_max = MIN2(reasonable_max, max_coop_heap);
1602     }
1603     reasonable_max = limit_by_allocatable_memory(reasonable_max);
1604 
1605     if (!FLAG_IS_DEFAULT(InitialHeapSize)) {
1606       // An initial heap size was specified on the command line,
1607       // so be sure that the maximum size is consistent.  Done
1608       // after call to limit_by_allocatable_memory because that
1609       // method might reduce the allocation size.
1610       reasonable_max = MAX2(reasonable_max, (julong)InitialHeapSize);
1611     }
1612 
1613     if (PrintGCDetails && Verbose) {
1614       // Cannot use gclog_or_tty yet.
1615       tty->print_cr("  Maximum heap size " SIZE_FORMAT, reasonable_max);
1616     }
1617     FLAG_SET_ERGO(uintx, MaxHeapSize, (uintx)reasonable_max);
1618   }
1619 
1620   // If the initial_heap_size has not been set with InitialHeapSize
1621   // or -Xms, then set it as fraction of the size of physical memory,
1622   // respecting the maximum and minimum sizes of the heap.
1623   if (FLAG_IS_DEFAULT(InitialHeapSize)) {
1624     julong reasonable_minimum = (julong)(OldSize + NewSize);
1625 
1626     reasonable_minimum = MIN2(reasonable_minimum, (julong)MaxHeapSize);
1627 
1628     reasonable_minimum = limit_by_allocatable_memory(reasonable_minimum);
1629 
1630     julong reasonable_initial = phys_mem / InitialRAMFraction;
1631 
1632     reasonable_initial = MAX2(reasonable_initial, reasonable_minimum);
1633     reasonable_initial = MIN2(reasonable_initial, (julong)MaxHeapSize);
1634 
1635     reasonable_initial = limit_by_allocatable_memory(reasonable_initial);
1636 
1637     if (PrintGCDetails && Verbose) {
1638       // Cannot use gclog_or_tty yet.
1639       tty->print_cr("  Initial heap size " SIZE_FORMAT, (uintx)reasonable_initial);
1640       tty->print_cr("  Minimum heap size " SIZE_FORMAT, (uintx)reasonable_minimum);
1641     }
1642     FLAG_SET_ERGO(uintx, InitialHeapSize, (uintx)reasonable_initial);
1643     set_min_heap_size((uintx)reasonable_minimum);
1644   }
1645 }
1646 
1647 // This must be called after ergonomics because we want bytecode rewriting
1648 // if the server compiler is used, or if UseSharedSpaces is disabled.
1649 void Arguments::set_bytecode_flags() {
1650   // Better not attempt to store into a read-only space.
1651   if (UseSharedSpaces) {
1652     FLAG_SET_DEFAULT(RewriteBytecodes, false);
1653     FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
1654   }
1655 
1656   if (!RewriteBytecodes) {
1657     FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
1658   }
1659 }
1660 
1661 // Aggressive optimization flags  -XX:+AggressiveOpts
1662 void Arguments::set_aggressive_opts_flags() {
1663 #ifdef COMPILER2
1664   if (AggressiveOpts || !FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
1665     if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
1666       FLAG_SET_DEFAULT(EliminateAutoBox, true);
1667     }
1668     if (FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
1669       FLAG_SET_DEFAULT(AutoBoxCacheMax, 20000);
1670     }
1671 
1672     // Feed the cache size setting into the JDK
1673     char buffer[1024];
1674     sprintf(buffer, "java.lang.Integer.IntegerCache.high=" INTX_FORMAT, AutoBoxCacheMax);
1675     add_property(buffer);
1676   }
1677   if (AggressiveOpts && FLAG_IS_DEFAULT(BiasedLockingStartupDelay)) {
1678     FLAG_SET_DEFAULT(BiasedLockingStartupDelay, 500);
1679   }
1680 #endif
1681 
1682   if (AggressiveOpts) {
1683 // Sample flag setting code
1684 //    if (FLAG_IS_DEFAULT(EliminateZeroing)) {
1685 //      FLAG_SET_DEFAULT(EliminateZeroing, true);
1686 //    }
1687   }
1688 }
1689 
1690 //===========================================================================================================
1691 // Parsing of java.compiler property
1692 
1693 void Arguments::process_java_compiler_argument(char* arg) {
1694   // For backwards compatibility, Djava.compiler=NONE or ""
1695   // causes us to switch to -Xint mode UNLESS -Xdebug
1696   // is also specified.
1697   if (strlen(arg) == 0 || strcasecmp(arg, "NONE") == 0) {
1698     set_java_compiler(true);    // "-Djava.compiler[=...]" most recently seen.
1699   }
1700 }
1701 
1702 void Arguments::process_java_launcher_argument(const char* launcher, void* extra_info) {
1703   _sun_java_launcher = strdup(launcher);
1704   if (strcmp("gamma", _sun_java_launcher) == 0) {
1705     _created_by_gamma_launcher = true;
1706   }
1707 }
1708 
1709 bool Arguments::created_by_java_launcher() {
1710   assert(_sun_java_launcher != NULL, "property must have value");
1711   return strcmp(DEFAULT_JAVA_LAUNCHER, _sun_java_launcher) != 0;
1712 }
1713 
1714 bool Arguments::created_by_gamma_launcher() {
1715   return _created_by_gamma_launcher;
1716 }
1717 
1718 //===========================================================================================================
1719 // Parsing of main arguments
1720 
1721 bool Arguments::verify_interval(uintx val, uintx min,
1722                                 uintx max, const char* name) {
1723   // Returns true iff value is in the inclusive interval [min..max]
1724   // false, otherwise.
1725   if (val >= min && val <= max) {
1726     return true;
1727   }
1728   jio_fprintf(defaultStream::error_stream(),
1729               "%s of " UINTX_FORMAT " is invalid; must be between " UINTX_FORMAT
1730               " and " UINTX_FORMAT "\n",
1731               name, val, min, max);
1732   return false;
1733 }
1734 
1735 bool Arguments::verify_min_value(intx val, intx min, const char* name) {
1736   // Returns true if given value is at least specified min threshold
1737   // false, otherwise.
1738   if (val >= min ) {
1739       return true;
1740   }
1741   jio_fprintf(defaultStream::error_stream(),
1742               "%s of " INTX_FORMAT " is invalid; must be at least " INTX_FORMAT "\n",
1743               name, val, min);
1744   return false;
1745 }
1746 
1747 bool Arguments::verify_percentage(uintx value, const char* name) {
1748   if (value <= 100) {
1749     return true;
1750   }
1751   jio_fprintf(defaultStream::error_stream(),
1752               "%s of " UINTX_FORMAT " is invalid; must be between 0 and 100\n",
1753               name, value);
1754   return false;
1755 }
1756 
1757 #if !INCLUDE_ALL_GCS
1758 #ifdef ASSERT
1759 static bool verify_serial_gc_flags() {
1760   return (UseSerialGC &&
1761         !(UseParNewGC || (UseConcMarkSweepGC || CMSIncrementalMode) || UseG1GC ||
1762           UseParallelGC || UseParallelOldGC));
1763 }
1764 #endif // ASSERT
1765 #endif // INCLUDE_ALL_GCS
1766 
1767 // check if do gclog rotation
1768 // +UseGCLogFileRotation is a must,
1769 // no gc log rotation when log file not supplied or
1770 // NumberOfGCLogFiles is 0, or GCLogFileSize is 0
1771 void check_gclog_consistency() {
1772   if (UseGCLogFileRotation) {
1773     if ((Arguments::gc_log_filename() == NULL) ||
1774         (NumberOfGCLogFiles == 0)  ||
1775         (GCLogFileSize == 0)) {
1776       jio_fprintf(defaultStream::output_stream(),
1777                   "To enable GC log rotation, use -Xloggc:<filename> -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=<num_of_files> -XX:GCLogFileSize=<num_of_size>\n"
1778                   "where num_of_file > 0 and num_of_size > 0\n"
1779                   "GC log rotation is turned off\n");
1780       UseGCLogFileRotation = false;
1781     }
1782   }
1783 
1784   if (UseGCLogFileRotation && GCLogFileSize < 8*K) {
1785         FLAG_SET_CMDLINE(uintx, GCLogFileSize, 8*K);
1786         jio_fprintf(defaultStream::output_stream(),
1787                     "GCLogFileSize changed to minimum 8K\n");
1788   }
1789 }
1790 
1791 // Check consistency of GC selection
1792 bool Arguments::check_gc_consistency() {
1793   check_gclog_consistency();
1794   bool status = true;
1795   // Ensure that the user has not selected conflicting sets
1796   // of collectors. [Note: this check is merely a user convenience;
1797   // collectors over-ride each other so that only a non-conflicting
1798   // set is selected; however what the user gets is not what they
1799   // may have expected from the combination they asked for. It's
1800   // better to reduce user confusion by not allowing them to
1801   // select conflicting combinations.
1802   uint i = 0;
1803   if (UseSerialGC)                       i++;
1804   if (UseConcMarkSweepGC || UseParNewGC) i++;
1805   if (UseParallelGC || UseParallelOldGC) i++;
1806   if (UseG1GC)                           i++;
1807   if (i > 1) {
1808     jio_fprintf(defaultStream::error_stream(),
1809                 "Conflicting collector combinations in option list; "
1810                 "please refer to the release notes for the combinations "
1811                 "allowed\n");
1812     status = false;
1813   }
1814 
1815   return status;
1816 }
1817 
1818 void Arguments::check_deprecated_gcs() {
1819   if (UseConcMarkSweepGC && !UseParNewGC) {
1820     warning("Using the DefNew young collector with the CMS collector is deprecated "
1821         "and will likely be removed in a future release");
1822   }
1823 
1824   if (UseParNewGC && !UseConcMarkSweepGC) {
1825     // !UseConcMarkSweepGC means that we are using serial old gc. Unfortunately we don't
1826     // set up UseSerialGC properly, so that can't be used in the check here.
1827     warning("Using the ParNew young collector with the Serial old collector is deprecated "
1828         "and will likely be removed in a future release");
1829   }
1830 
1831   if (CMSIncrementalMode) {
1832     warning("Using incremental CMS is deprecated and will likely be removed in a future release");
1833   }
1834 }
1835 
1836 void Arguments::check_deprecated_gc_flags() {
1837   if (FLAG_IS_CMDLINE(MaxGCMinorPauseMillis)) {
1838     warning("Using MaxGCMinorPauseMillis as minor pause goal is deprecated"
1839             "and will likely be removed in future release");
1840   }
1841 }
1842 
1843 // Check stack pages settings
1844 bool Arguments::check_stack_pages()
1845 {
1846   bool status = true;
1847   status = status && verify_min_value(StackYellowPages, 1, "StackYellowPages");
1848   status = status && verify_min_value(StackRedPages, 1, "StackRedPages");
1849   // greater stack shadow pages can't generate instruction to bang stack
1850   status = status && verify_interval(StackShadowPages, 1, 50, "StackShadowPages");
1851   return status;
1852 }
1853 
1854 // Check the consistency of vm_init_args
1855 bool Arguments::check_vm_args_consistency() {
1856   // Method for adding checks for flag consistency.
1857   // The intent is to warn the user of all possible conflicts,
1858   // before returning an error.
1859   // Note: Needs platform-dependent factoring.
1860   bool status = true;
1861 
1862 #if ( (defined(COMPILER2) && defined(SPARC)))
1863   // NOTE: The call to VM_Version_init depends on the fact that VM_Version_init
1864   // on sparc doesn't require generation of a stub as is the case on, e.g.,
1865   // x86.  Normally, VM_Version_init must be called from init_globals in
1866   // init.cpp, which is called by the initial java thread *after* arguments
1867   // have been parsed.  VM_Version_init gets called twice on sparc.
1868   extern void VM_Version_init();
1869   VM_Version_init();
1870   if (!VM_Version::has_v9()) {
1871     jio_fprintf(defaultStream::error_stream(),
1872                 "V8 Machine detected, Server requires V9\n");
1873     status = false;
1874   }
1875 #endif /* COMPILER2 && SPARC */
1876 
1877   // Allow both -XX:-UseStackBanging and -XX:-UseBoundThreads in non-product
1878   // builds so the cost of stack banging can be measured.
1879 #if (defined(PRODUCT) && defined(SOLARIS))
1880   if (!UseBoundThreads && !UseStackBanging) {
1881     jio_fprintf(defaultStream::error_stream(),
1882                 "-UseStackBanging conflicts with -UseBoundThreads\n");
1883 
1884      status = false;
1885   }
1886 #endif
1887 
1888   if (TLABRefillWasteFraction == 0) {
1889     jio_fprintf(defaultStream::error_stream(),
1890                 "TLABRefillWasteFraction should be a denominator, "
1891                 "not " SIZE_FORMAT "\n",
1892                 TLABRefillWasteFraction);
1893     status = false;
1894   }
1895 
1896   status = status && verify_percentage(AdaptiveSizePolicyWeight,
1897                               "AdaptiveSizePolicyWeight");
1898   status = status && verify_percentage(ThresholdTolerance, "ThresholdTolerance");
1899   status = status && verify_percentage(MinHeapFreeRatio, "MinHeapFreeRatio");
1900   status = status && verify_percentage(MaxHeapFreeRatio, "MaxHeapFreeRatio");
1901 
1902   // Divide by bucket size to prevent a large size from causing rollover when
1903   // calculating amount of memory needed to be allocated for the String table.
1904   status = status && verify_interval(StringTableSize, minimumStringTableSize,
1905     (max_uintx / StringTable::bucket_size()), "StringTable size");
1906 
1907   if (MinHeapFreeRatio > MaxHeapFreeRatio) {
1908     jio_fprintf(defaultStream::error_stream(),
1909                 "MinHeapFreeRatio (" UINTX_FORMAT ") must be less than or "
1910                 "equal to MaxHeapFreeRatio (" UINTX_FORMAT ")\n",
1911                 MinHeapFreeRatio, MaxHeapFreeRatio);
1912     status = false;
1913   }
1914   // Keeping the heap 100% free is hard ;-) so limit it to 99%.
1915   MinHeapFreeRatio = MIN2(MinHeapFreeRatio, (uintx) 99);
1916 
1917   // Min/MaxMetaspaceFreeRatio
1918   status = status && verify_percentage(MinMetaspaceFreeRatio, "MinMetaspaceFreeRatio");
1919   status = status && verify_percentage(MaxMetaspaceFreeRatio, "MaxMetaspaceFreeRatio");
1920 
1921   if (MinMetaspaceFreeRatio > MaxMetaspaceFreeRatio) {
1922     jio_fprintf(defaultStream::error_stream(),
1923                 "MinMetaspaceFreeRatio (%s" UINTX_FORMAT ") must be less than or "
1924                 "equal to MaxMetaspaceFreeRatio (%s" UINTX_FORMAT ")\n",
1925                 FLAG_IS_DEFAULT(MinMetaspaceFreeRatio) ? "Default: " : "",
1926                 MinMetaspaceFreeRatio,
1927                 FLAG_IS_DEFAULT(MaxMetaspaceFreeRatio) ? "Default: " : "",
1928                 MaxMetaspaceFreeRatio);
1929     status = false;
1930   }
1931 
1932   // Trying to keep 100% free is not practical
1933   MinMetaspaceFreeRatio = MIN2(MinMetaspaceFreeRatio, (uintx) 99);
1934 
1935   if (FullGCALot && FLAG_IS_DEFAULT(MarkSweepAlwaysCompactCount)) {
1936     MarkSweepAlwaysCompactCount = 1;  // Move objects every gc.
1937   }
1938 
1939   if (UseParallelOldGC && ParallelOldGCSplitALot) {
1940     // Settings to encourage splitting.
1941     if (!FLAG_IS_CMDLINE(NewRatio)) {
1942       FLAG_SET_CMDLINE(uintx, NewRatio, 2);
1943     }
1944     if (!FLAG_IS_CMDLINE(ScavengeBeforeFullGC)) {
1945       FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
1946     }
1947   }
1948 
1949   status = status && verify_percentage(GCHeapFreeLimit, "GCHeapFreeLimit");
1950   status = status && verify_percentage(GCTimeLimit, "GCTimeLimit");
1951   if (GCTimeLimit == 100) {
1952     // Turn off gc-overhead-limit-exceeded checks
1953     FLAG_SET_DEFAULT(UseGCOverheadLimit, false);
1954   }
1955 
1956   status = status && verify_percentage(GCHeapFreeLimit, "GCHeapFreeLimit");
1957 
1958   status = status && check_gc_consistency();
1959   status = status && check_stack_pages();
1960 
1961   if (_has_alloc_profile) {
1962     if (UseParallelGC || UseParallelOldGC) {
1963       jio_fprintf(defaultStream::error_stream(),
1964                   "error:  invalid argument combination.\n"
1965                   "Allocation profiling (-Xaprof) cannot be used together with "
1966                   "Parallel GC (-XX:+UseParallelGC or -XX:+UseParallelOldGC).\n");
1967       status = false;
1968     }
1969     if (UseConcMarkSweepGC) {
1970       jio_fprintf(defaultStream::error_stream(),
1971                   "error:  invalid argument combination.\n"
1972                   "Allocation profiling (-Xaprof) cannot be used together with "
1973                   "the CMS collector (-XX:+UseConcMarkSweepGC).\n");
1974       status = false;
1975     }
1976   }
1977 
1978   if (CMSIncrementalMode) {
1979     if (!UseConcMarkSweepGC) {
1980       jio_fprintf(defaultStream::error_stream(),
1981                   "error:  invalid argument combination.\n"
1982                   "The CMS collector (-XX:+UseConcMarkSweepGC) must be "
1983                   "selected in order\nto use CMSIncrementalMode.\n");
1984       status = false;
1985     } else {
1986       status = status && verify_percentage(CMSIncrementalDutyCycle,
1987                                   "CMSIncrementalDutyCycle");
1988       status = status && verify_percentage(CMSIncrementalDutyCycleMin,
1989                                   "CMSIncrementalDutyCycleMin");
1990       status = status && verify_percentage(CMSIncrementalSafetyFactor,
1991                                   "CMSIncrementalSafetyFactor");
1992       status = status && verify_percentage(CMSIncrementalOffset,
1993                                   "CMSIncrementalOffset");
1994       status = status && verify_percentage(CMSExpAvgFactor,
1995                                   "CMSExpAvgFactor");
1996       // If it was not set on the command line, set
1997       // CMSInitiatingOccupancyFraction to 1 so icms can initiate cycles early.
1998       if (CMSInitiatingOccupancyFraction < 0) {
1999         FLAG_SET_DEFAULT(CMSInitiatingOccupancyFraction, 1);
2000       }
2001     }
2002   }
2003 
2004   // CMS space iteration, which FLSVerifyAllHeapreferences entails,
2005   // insists that we hold the requisite locks so that the iteration is
2006   // MT-safe. For the verification at start-up and shut-down, we don't
2007   // yet have a good way of acquiring and releasing these locks,
2008   // which are not visible at the CollectedHeap level. We want to
2009   // be able to acquire these locks and then do the iteration rather
2010   // than just disable the lock verification. This will be fixed under
2011   // bug 4788986.
2012   if (UseConcMarkSweepGC && FLSVerifyAllHeapReferences) {
2013     if (VerifyDuringStartup) {
2014       warning("Heap verification at start-up disabled "
2015               "(due to current incompatibility with FLSVerifyAllHeapReferences)");
2016       VerifyDuringStartup = false; // Disable verification at start-up
2017     }
2018 
2019     if (VerifyBeforeExit) {
2020       warning("Heap verification at shutdown disabled "
2021               "(due to current incompatibility with FLSVerifyAllHeapReferences)");
2022       VerifyBeforeExit = false; // Disable verification at shutdown
2023     }
2024   }
2025 
2026   // Note: only executed in non-PRODUCT mode
2027   if (!UseAsyncConcMarkSweepGC &&
2028       (ExplicitGCInvokesConcurrent ||
2029        ExplicitGCInvokesConcurrentAndUnloadsClasses)) {
2030     jio_fprintf(defaultStream::error_stream(),
2031                 "error: +ExplicitGCInvokesConcurrent[AndUnloadsClasses] conflicts"
2032                 " with -UseAsyncConcMarkSweepGC");
2033     status = false;
2034   }
2035 
2036   status = status && verify_min_value(ParGCArrayScanChunk, 1, "ParGCArrayScanChunk");
2037 
2038 #if INCLUDE_ALL_GCS
2039   if (UseG1GC) {
2040     status = status && verify_percentage(InitiatingHeapOccupancyPercent,
2041                                          "InitiatingHeapOccupancyPercent");
2042     status = status && verify_min_value(G1RefProcDrainInterval, 1,
2043                                         "G1RefProcDrainInterval");
2044     status = status && verify_min_value((intx)G1ConcMarkStepDurationMillis, 1,
2045                                         "G1ConcMarkStepDurationMillis");
2046   }
2047 #endif // INCLUDE_ALL_GCS
2048 
2049   status = status && verify_interval(RefDiscoveryPolicy,
2050                                      ReferenceProcessor::DiscoveryPolicyMin,
2051                                      ReferenceProcessor::DiscoveryPolicyMax,
2052                                      "RefDiscoveryPolicy");
2053 
2054   // Limit the lower bound of this flag to 1 as it is used in a division
2055   // expression.
2056   status = status && verify_interval(TLABWasteTargetPercent,
2057                                      1, 100, "TLABWasteTargetPercent");
2058 
2059   status = status && verify_object_alignment();
2060 
2061   status = status && verify_min_value(ClassMetaspaceSize, 1*M,
2062                                       "ClassMetaspaceSize");
2063 
2064   status = status && verify_interval(MarkStackSizeMax,
2065                                   1, (max_jint - 1), "MarkStackSizeMax");
2066 
2067 #ifdef SPARC
2068   if (UseConcMarkSweepGC || UseG1GC) {
2069     // Issue a stern warning if the user has explicitly set
2070     // UseMemSetInBOT (it is known to cause issues), but allow
2071     // use for experimentation and debugging.
2072     if (VM_Version::is_sun4v() && UseMemSetInBOT) {
2073       assert(!FLAG_IS_DEFAULT(UseMemSetInBOT), "Error");
2074       warning("Experimental flag -XX:+UseMemSetInBOT is known to cause instability"
2075           " on sun4v; please understand that you are using at your own risk!");
2076     }
2077   }
2078 #endif // SPARC
2079 
2080   if (PrintNMTStatistics) {
2081 #if INCLUDE_NMT
2082     if (MemTracker::tracking_level() == MemTracker::NMT_off) {
2083 #endif // INCLUDE_NMT
2084       warning("PrintNMTStatistics is disabled, because native memory tracking is not enabled");
2085       PrintNMTStatistics = false;
2086 #if INCLUDE_NMT
2087     }
2088 #endif
2089   }
2090 
2091   return status;
2092 }
2093 
2094 bool Arguments::is_bad_option(const JavaVMOption* option, jboolean ignore,
2095   const char* option_type) {
2096   if (ignore) return false;
2097 
2098   const char* spacer = " ";
2099   if (option_type == NULL) {
2100     option_type = ++spacer; // Set both to the empty string.
2101   }
2102 
2103   if (os::obsolete_option(option)) {
2104     jio_fprintf(defaultStream::error_stream(),
2105                 "Obsolete %s%soption: %s\n", option_type, spacer,
2106       option->optionString);
2107     return false;
2108   } else {
2109     jio_fprintf(defaultStream::error_stream(),
2110                 "Unrecognized %s%soption: %s\n", option_type, spacer,
2111       option->optionString);
2112     return true;
2113   }
2114 }
2115 
2116 static const char* user_assertion_options[] = {
2117   "-da", "-ea", "-disableassertions", "-enableassertions", 0
2118 };
2119 
2120 static const char* system_assertion_options[] = {
2121   "-dsa", "-esa", "-disablesystemassertions", "-enablesystemassertions", 0
2122 };
2123 
2124 // Return true if any of the strings in null-terminated array 'names' matches.
2125 // If tail_allowed is true, then the tail must begin with a colon; otherwise,
2126 // the option must match exactly.
2127 static bool match_option(const JavaVMOption* option, const char** names, const char** tail,
2128   bool tail_allowed) {
2129   for (/* empty */; *names != NULL; ++names) {
2130     if (match_option(option, *names, tail)) {
2131       if (**tail == '\0' || tail_allowed && **tail == ':') {
2132         return true;
2133       }
2134     }
2135   }
2136   return false;
2137 }
2138 
2139 bool Arguments::parse_uintx(const char* value,
2140                             uintx* uintx_arg,
2141                             uintx min_size) {
2142 
2143   // Check the sign first since atomull() parses only unsigned values.
2144   bool value_is_positive = !(*value == '-');
2145 
2146   if (value_is_positive) {
2147     julong n;
2148     bool good_return = atomull(value, &n);
2149     if (good_return) {
2150       bool above_minimum = n >= min_size;
2151       bool value_is_too_large = n > max_uintx;
2152 
2153       if (above_minimum && !value_is_too_large) {
2154         *uintx_arg = n;
2155         return true;
2156       }
2157     }
2158   }
2159   return false;
2160 }
2161 
2162 Arguments::ArgsRange Arguments::parse_memory_size(const char* s,
2163                                                   julong* long_arg,
2164                                                   julong min_size) {
2165   if (!atomull(s, long_arg)) return arg_unreadable;
2166   return check_memory_size(*long_arg, min_size);
2167 }
2168 
2169 // Parse JavaVMInitArgs structure
2170 
2171 jint Arguments::parse_vm_init_args(const JavaVMInitArgs* args) {
2172   // For components of the system classpath.
2173   SysClassPath scp(Arguments::get_sysclasspath());
2174   bool scp_assembly_required = false;
2175 
2176   // Save default settings for some mode flags
2177   Arguments::_AlwaysCompileLoopMethods = AlwaysCompileLoopMethods;
2178   Arguments::_UseOnStackReplacement    = UseOnStackReplacement;
2179   Arguments::_ClipInlining             = ClipInlining;
2180   Arguments::_BackgroundCompilation    = BackgroundCompilation;
2181 
2182   // Setup flags for mixed which is the default
2183   set_mode_flags(_mixed);
2184 
2185   // Parse JAVA_TOOL_OPTIONS environment variable (if present)
2186   jint result = parse_java_tool_options_environment_variable(&scp, &scp_assembly_required);
2187   if (result != JNI_OK) {
2188     return result;
2189   }
2190 
2191   // Parse JavaVMInitArgs structure passed in
2192   result = parse_each_vm_init_arg(args, &scp, &scp_assembly_required, COMMAND_LINE);
2193   if (result != JNI_OK) {
2194     return result;
2195   }
2196 
2197   if (AggressiveOpts) {
2198     // Insert alt-rt.jar between user-specified bootclasspath
2199     // prefix and the default bootclasspath.  os::set_boot_path()
2200     // uses meta_index_dir as the default bootclasspath directory.
2201     const char* altclasses_jar = "alt-rt.jar";
2202     size_t altclasses_path_len = strlen(get_meta_index_dir()) + 1 +
2203                                  strlen(altclasses_jar);
2204     char* altclasses_path = NEW_C_HEAP_ARRAY(char, altclasses_path_len, mtInternal);
2205     strcpy(altclasses_path, get_meta_index_dir());
2206     strcat(altclasses_path, altclasses_jar);
2207     scp.add_suffix_to_prefix(altclasses_path);
2208     scp_assembly_required = true;
2209     FREE_C_HEAP_ARRAY(char, altclasses_path, mtInternal);
2210   }
2211 
2212   // Parse _JAVA_OPTIONS environment variable (if present) (mimics classic VM)
2213   result = parse_java_options_environment_variable(&scp, &scp_assembly_required);
2214   if (result != JNI_OK) {
2215     return result;
2216   }
2217 
2218   // Do final processing now that all arguments have been parsed
2219   result = finalize_vm_init_args(&scp, scp_assembly_required);
2220   if (result != JNI_OK) {
2221     return result;
2222   }
2223 
2224   return JNI_OK;
2225 }
2226 
2227 jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args,
2228                                        SysClassPath* scp_p,
2229                                        bool* scp_assembly_required_p,
2230                                        FlagValueOrigin origin) {
2231   // Remaining part of option string
2232   const char* tail;
2233 
2234   // iterate over arguments
2235   for (int index = 0; index < args->nOptions; index++) {
2236     bool is_absolute_path = false;  // for -agentpath vs -agentlib
2237 
2238     const JavaVMOption* option = args->options + index;
2239 
2240     if (!match_option(option, "-Djava.class.path", &tail) &&
2241         !match_option(option, "-Dsun.java.command", &tail) &&
2242         !match_option(option, "-Dsun.java.launcher", &tail)) {
2243 
2244         // add all jvm options to the jvm_args string. This string
2245         // is used later to set the java.vm.args PerfData string constant.
2246         // the -Djava.class.path and the -Dsun.java.command options are
2247         // omitted from jvm_args string as each have their own PerfData
2248         // string constant object.
2249         build_jvm_args(option->optionString);
2250     }
2251 
2252     // -verbose:[class/gc/jni]
2253     if (match_option(option, "-verbose", &tail)) {
2254       if (!strcmp(tail, ":class") || !strcmp(tail, "")) {
2255         FLAG_SET_CMDLINE(bool, TraceClassLoading, true);
2256         FLAG_SET_CMDLINE(bool, TraceClassUnloading, true);
2257       } else if (!strcmp(tail, ":gc")) {
2258         FLAG_SET_CMDLINE(bool, PrintGC, true);
2259       } else if (!strcmp(tail, ":jni")) {
2260         FLAG_SET_CMDLINE(bool, PrintJNIResolving, true);
2261       }
2262     // -da / -ea / -disableassertions / -enableassertions
2263     // These accept an optional class/package name separated by a colon, e.g.,
2264     // -da:java.lang.Thread.
2265     } else if (match_option(option, user_assertion_options, &tail, true)) {
2266       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2267       if (*tail == '\0') {
2268         JavaAssertions::setUserClassDefault(enable);
2269       } else {
2270         assert(*tail == ':', "bogus match by match_option()");
2271         JavaAssertions::addOption(tail + 1, enable);
2272       }
2273     // -dsa / -esa / -disablesystemassertions / -enablesystemassertions
2274     } else if (match_option(option, system_assertion_options, &tail, false)) {
2275       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2276       JavaAssertions::setSystemClassDefault(enable);
2277     // -bootclasspath:
2278     } else if (match_option(option, "-Xbootclasspath:", &tail)) {
2279       scp_p->reset_path(tail);
2280       *scp_assembly_required_p = true;
2281     // -bootclasspath/a:
2282     } else if (match_option(option, "-Xbootclasspath/a:", &tail)) {
2283       scp_p->add_suffix(tail);
2284       *scp_assembly_required_p = true;
2285     // -bootclasspath/p:
2286     } else if (match_option(option, "-Xbootclasspath/p:", &tail)) {
2287       scp_p->add_prefix(tail);
2288       *scp_assembly_required_p = true;
2289     // -Xrun
2290     } else if (match_option(option, "-Xrun", &tail)) {
2291       if (tail != NULL) {
2292         const char* pos = strchr(tail, ':');
2293         size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
2294         char* name = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len + 1, mtInternal), tail, len);
2295         name[len] = '\0';
2296 
2297         char *options = NULL;
2298         if(pos != NULL) {
2299           size_t len2 = strlen(pos+1) + 1; // options start after ':'.  Final zero must be copied.
2300           options = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len2, mtInternal), pos+1, len2);
2301         }
2302 #if !INCLUDE_JVMTI
2303         if ((strcmp(name, "hprof") == 0) || (strcmp(name, "jdwp") == 0)) {
2304           jio_fprintf(defaultStream::error_stream(),
2305             "Profiling and debugging agents are not supported in this VM\n");
2306           return JNI_ERR;
2307         }
2308 #endif // !INCLUDE_JVMTI
2309         add_init_library(name, options);
2310       }
2311     // -agentlib and -agentpath
2312     } else if (match_option(option, "-agentlib:", &tail) ||
2313           (is_absolute_path = match_option(option, "-agentpath:", &tail))) {
2314       if(tail != NULL) {
2315         const char* pos = strchr(tail, '=');
2316         size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
2317         char* name = strncpy(NEW_C_HEAP_ARRAY(char, len + 1, mtInternal), tail, len);
2318         name[len] = '\0';
2319 
2320         char *options = NULL;
2321         if(pos != NULL) {
2322           options = strcpy(NEW_C_HEAP_ARRAY(char, strlen(pos + 1) + 1, mtInternal), pos + 1);
2323         }
2324 #if !INCLUDE_JVMTI
2325         if ((strcmp(name, "hprof") == 0) || (strcmp(name, "jdwp") == 0)) {
2326           jio_fprintf(defaultStream::error_stream(),
2327             "Profiling and debugging agents are not supported in this VM\n");
2328           return JNI_ERR;
2329         }
2330 #endif // !INCLUDE_JVMTI
2331         add_init_agent(name, options, is_absolute_path);
2332       }
2333     // -javaagent
2334     } else if (match_option(option, "-javaagent:", &tail)) {
2335 #if !INCLUDE_JVMTI
2336       jio_fprintf(defaultStream::error_stream(),
2337         "Instrumentation agents are not supported in this VM\n");
2338       return JNI_ERR;
2339 #else
2340       if(tail != NULL) {
2341         char *options = strcpy(NEW_C_HEAP_ARRAY(char, strlen(tail) + 1, mtInternal), tail);
2342         add_init_agent("instrument", options, false);
2343       }
2344 #endif // !INCLUDE_JVMTI
2345     // -Xnoclassgc
2346     } else if (match_option(option, "-Xnoclassgc", &tail)) {
2347       FLAG_SET_CMDLINE(bool, ClassUnloading, false);
2348     // -Xincgc: i-CMS
2349     } else if (match_option(option, "-Xincgc", &tail)) {
2350       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, true);
2351       FLAG_SET_CMDLINE(bool, CMSIncrementalMode, true);
2352     // -Xnoincgc: no i-CMS
2353     } else if (match_option(option, "-Xnoincgc", &tail)) {
2354       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, false);
2355       FLAG_SET_CMDLINE(bool, CMSIncrementalMode, false);
2356     // -Xconcgc
2357     } else if (match_option(option, "-Xconcgc", &tail)) {
2358       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, true);
2359     // -Xnoconcgc
2360     } else if (match_option(option, "-Xnoconcgc", &tail)) {
2361       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, false);
2362     // -Xbatch
2363     } else if (match_option(option, "-Xbatch", &tail)) {
2364       FLAG_SET_CMDLINE(bool, BackgroundCompilation, false);
2365     // -Xmn for compatibility with other JVM vendors
2366     } else if (match_option(option, "-Xmn", &tail)) {
2367       julong long_initial_eden_size = 0;
2368       ArgsRange errcode = parse_memory_size(tail, &long_initial_eden_size, 1);
2369       if (errcode != arg_in_range) {
2370         jio_fprintf(defaultStream::error_stream(),
2371                     "Invalid initial eden size: %s\n", option->optionString);
2372         describe_range_error(errcode);
2373         return JNI_EINVAL;
2374       }
2375       FLAG_SET_CMDLINE(uintx, MaxNewSize, (uintx)long_initial_eden_size);
2376       FLAG_SET_CMDLINE(uintx, NewSize, (uintx)long_initial_eden_size);
2377     // -Xms
2378     } else if (match_option(option, "-Xms", &tail)) {
2379       julong long_initial_heap_size = 0;
2380       ArgsRange errcode = parse_memory_size(tail, &long_initial_heap_size, 1);
2381       if (errcode != arg_in_range) {
2382         jio_fprintf(defaultStream::error_stream(),
2383                     "Invalid initial heap size: %s\n", option->optionString);
2384         describe_range_error(errcode);
2385         return JNI_EINVAL;
2386       }
2387       FLAG_SET_CMDLINE(uintx, InitialHeapSize, (uintx)long_initial_heap_size);
2388       // Currently the minimum size and the initial heap sizes are the same.
2389       set_min_heap_size(InitialHeapSize);
2390     // -Xmx
2391     } else if (match_option(option, "-Xmx", &tail)) {
2392       julong long_max_heap_size = 0;
2393       ArgsRange errcode = parse_memory_size(tail, &long_max_heap_size, 1);
2394       if (errcode != arg_in_range) {
2395         jio_fprintf(defaultStream::error_stream(),
2396                     "Invalid maximum heap size: %s\n", option->optionString);
2397         describe_range_error(errcode);
2398         return JNI_EINVAL;
2399       }
2400       FLAG_SET_CMDLINE(uintx, MaxHeapSize, (uintx)long_max_heap_size);
2401     // Xmaxf
2402     } else if (match_option(option, "-Xmaxf", &tail)) {
2403       int maxf = (int)(atof(tail) * 100);
2404       if (maxf < 0 || maxf > 100) {
2405         jio_fprintf(defaultStream::error_stream(),
2406                     "Bad max heap free percentage size: %s\n",
2407                     option->optionString);
2408         return JNI_EINVAL;
2409       } else {
2410         FLAG_SET_CMDLINE(uintx, MaxHeapFreeRatio, maxf);
2411       }
2412     // Xminf
2413     } else if (match_option(option, "-Xminf", &tail)) {
2414       int minf = (int)(atof(tail) * 100);
2415       if (minf < 0 || minf > 100) {
2416         jio_fprintf(defaultStream::error_stream(),
2417                     "Bad min heap free percentage size: %s\n",
2418                     option->optionString);
2419         return JNI_EINVAL;
2420       } else {
2421         FLAG_SET_CMDLINE(uintx, MinHeapFreeRatio, minf);
2422       }
2423     // -Xss
2424     } else if (match_option(option, "-Xss", &tail)) {
2425       julong long_ThreadStackSize = 0;
2426       ArgsRange errcode = parse_memory_size(tail, &long_ThreadStackSize, 1000);
2427       if (errcode != arg_in_range) {
2428         jio_fprintf(defaultStream::error_stream(),
2429                     "Invalid thread stack size: %s\n", option->optionString);
2430         describe_range_error(errcode);
2431         return JNI_EINVAL;
2432       }
2433       // Internally track ThreadStackSize in units of 1024 bytes.
2434       FLAG_SET_CMDLINE(intx, ThreadStackSize,
2435                               round_to((int)long_ThreadStackSize, K) / K);
2436     // -Xoss
2437     } else if (match_option(option, "-Xoss", &tail)) {
2438           // HotSpot does not have separate native and Java stacks, ignore silently for compatibility
2439     // -Xmaxjitcodesize
2440     } else if (match_option(option, "-Xmaxjitcodesize", &tail) ||
2441                match_option(option, "-XX:ReservedCodeCacheSize=", &tail)) {
2442       julong long_ReservedCodeCacheSize = 0;
2443       ArgsRange errcode = parse_memory_size(tail, &long_ReservedCodeCacheSize,
2444                                             (size_t)InitialCodeCacheSize);
2445       if (errcode != arg_in_range) {
2446         jio_fprintf(defaultStream::error_stream(),
2447                     "Invalid maximum code cache size: %s. Should be greater than InitialCodeCacheSize=%dK\n",
2448                     option->optionString, InitialCodeCacheSize/K);
2449         describe_range_error(errcode);
2450         return JNI_EINVAL;
2451       }
2452       FLAG_SET_CMDLINE(uintx, ReservedCodeCacheSize, (uintx)long_ReservedCodeCacheSize);
2453     // -green
2454     } else if (match_option(option, "-green", &tail)) {
2455       jio_fprintf(defaultStream::error_stream(),
2456                   "Green threads support not available\n");
2457           return JNI_EINVAL;
2458     // -native
2459     } else if (match_option(option, "-native", &tail)) {
2460           // HotSpot always uses native threads, ignore silently for compatibility
2461     // -Xsqnopause
2462     } else if (match_option(option, "-Xsqnopause", &tail)) {
2463           // EVM option, ignore silently for compatibility
2464     // -Xrs
2465     } else if (match_option(option, "-Xrs", &tail)) {
2466           // Classic/EVM option, new functionality
2467       FLAG_SET_CMDLINE(bool, ReduceSignalUsage, true);
2468     } else if (match_option(option, "-Xusealtsigs", &tail)) {
2469           // change default internal VM signals used - lower case for back compat
2470       FLAG_SET_CMDLINE(bool, UseAltSigs, true);
2471     // -Xoptimize
2472     } else if (match_option(option, "-Xoptimize", &tail)) {
2473           // EVM option, ignore silently for compatibility
2474     // -Xprof
2475     } else if (match_option(option, "-Xprof", &tail)) {
2476 #if INCLUDE_FPROF
2477       _has_profile = true;
2478 #else // INCLUDE_FPROF
2479       jio_fprintf(defaultStream::error_stream(),
2480         "Flat profiling is not supported in this VM.\n");
2481       return JNI_ERR;
2482 #endif // INCLUDE_FPROF
2483     // -Xaprof
2484     } else if (match_option(option, "-Xaprof", &tail)) {
2485       _has_alloc_profile = true;
2486     // -Xconcurrentio
2487     } else if (match_option(option, "-Xconcurrentio", &tail)) {
2488       FLAG_SET_CMDLINE(bool, UseLWPSynchronization, true);
2489       FLAG_SET_CMDLINE(bool, BackgroundCompilation, false);
2490       FLAG_SET_CMDLINE(intx, DeferThrSuspendLoopCount, 1);
2491       FLAG_SET_CMDLINE(bool, UseTLAB, false);
2492       FLAG_SET_CMDLINE(uintx, NewSizeThreadIncrease, 16 * K);  // 20Kb per thread added to new generation
2493 
2494       // -Xinternalversion
2495     } else if (match_option(option, "-Xinternalversion", &tail)) {
2496       jio_fprintf(defaultStream::output_stream(), "%s\n",
2497                   VM_Version::internal_vm_info_string());
2498       vm_exit(0);
2499 #ifndef PRODUCT
2500     // -Xprintflags
2501     } else if (match_option(option, "-Xprintflags", &tail)) {
2502       CommandLineFlags::printFlags(tty, false);
2503       vm_exit(0);
2504 #endif
2505     // -D
2506     } else if (match_option(option, "-D", &tail)) {
2507       if (!add_property(tail)) {
2508         return JNI_ENOMEM;
2509       }
2510       // Out of the box management support
2511       if (match_option(option, "-Dcom.sun.management", &tail)) {
2512 #if INCLUDE_MANAGEMENT
2513         FLAG_SET_CMDLINE(bool, ManagementServer, true);
2514 #else
2515         jio_fprintf(defaultStream::output_stream(),
2516           "-Dcom.sun.management is not supported in this VM.\n");
2517         return JNI_ERR;
2518 #endif
2519       }
2520     // -Xint
2521     } else if (match_option(option, "-Xint", &tail)) {
2522           set_mode_flags(_int);
2523     // -Xmixed
2524     } else if (match_option(option, "-Xmixed", &tail)) {
2525           set_mode_flags(_mixed);
2526     // -Xcomp
2527     } else if (match_option(option, "-Xcomp", &tail)) {
2528       // for testing the compiler; turn off all flags that inhibit compilation
2529           set_mode_flags(_comp);
2530     // -Xshare:dump
2531     } else if (match_option(option, "-Xshare:dump", &tail)) {
2532       FLAG_SET_CMDLINE(bool, DumpSharedSpaces, true);
2533       set_mode_flags(_int);     // Prevent compilation, which creates objects
2534     // -Xshare:on
2535     } else if (match_option(option, "-Xshare:on", &tail)) {
2536       FLAG_SET_CMDLINE(bool, UseSharedSpaces, true);
2537       FLAG_SET_CMDLINE(bool, RequireSharedSpaces, true);
2538     // -Xshare:auto
2539     } else if (match_option(option, "-Xshare:auto", &tail)) {
2540       FLAG_SET_CMDLINE(bool, UseSharedSpaces, true);
2541       FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false);
2542     // -Xshare:off
2543     } else if (match_option(option, "-Xshare:off", &tail)) {
2544       FLAG_SET_CMDLINE(bool, UseSharedSpaces, false);
2545       FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false);
2546     // -Xverify
2547     } else if (match_option(option, "-Xverify", &tail)) {
2548       if (strcmp(tail, ":all") == 0 || strcmp(tail, "") == 0) {
2549         FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, true);
2550         FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true);
2551       } else if (strcmp(tail, ":remote") == 0) {
2552         FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false);
2553         FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true);
2554       } else if (strcmp(tail, ":none") == 0) {
2555         FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false);
2556         FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, false);
2557       } else if (is_bad_option(option, args->ignoreUnrecognized, "verification")) {
2558         return JNI_EINVAL;
2559       }
2560     // -Xdebug
2561     } else if (match_option(option, "-Xdebug", &tail)) {
2562       // note this flag has been used, then ignore
2563       set_xdebug_mode(true);
2564     // -Xnoagent
2565     } else if (match_option(option, "-Xnoagent", &tail)) {
2566       // For compatibility with classic. HotSpot refuses to load the old style agent.dll.
2567     } else if (match_option(option, "-Xboundthreads", &tail)) {
2568       // Bind user level threads to kernel threads (Solaris only)
2569       FLAG_SET_CMDLINE(bool, UseBoundThreads, true);
2570     } else if (match_option(option, "-Xloggc:", &tail)) {
2571       // Redirect GC output to the file. -Xloggc:<filename>
2572       // ostream_init_log(), when called will use this filename
2573       // to initialize a fileStream.
2574       _gc_log_filename = strdup(tail);
2575       FLAG_SET_CMDLINE(bool, PrintGC, true);
2576       FLAG_SET_CMDLINE(bool, PrintGCTimeStamps, true);
2577 
2578     // JNI hooks
2579     } else if (match_option(option, "-Xcheck", &tail)) {
2580       if (!strcmp(tail, ":jni")) {
2581 #if !INCLUDE_JNI_CHECK
2582         warning("JNI CHECKING is not supported in this VM");
2583 #else
2584         CheckJNICalls = true;
2585 #endif // INCLUDE_JNI_CHECK
2586       } else if (is_bad_option(option, args->ignoreUnrecognized,
2587                                      "check")) {
2588         return JNI_EINVAL;
2589       }
2590     } else if (match_option(option, "vfprintf", &tail)) {
2591       _vfprintf_hook = CAST_TO_FN_PTR(vfprintf_hook_t, option->extraInfo);
2592     } else if (match_option(option, "exit", &tail)) {
2593       _exit_hook = CAST_TO_FN_PTR(exit_hook_t, option->extraInfo);
2594     } else if (match_option(option, "abort", &tail)) {
2595       _abort_hook = CAST_TO_FN_PTR(abort_hook_t, option->extraInfo);
2596     // -XX:+AggressiveHeap
2597     } else if (match_option(option, "-XX:+AggressiveHeap", &tail)) {
2598 
2599       // This option inspects the machine and attempts to set various
2600       // parameters to be optimal for long-running, memory allocation
2601       // intensive jobs.  It is intended for machines with large
2602       // amounts of cpu and memory.
2603 
2604       // initHeapSize is needed since _initial_heap_size is 4 bytes on a 32 bit
2605       // VM, but we may not be able to represent the total physical memory
2606       // available (like having 8gb of memory on a box but using a 32bit VM).
2607       // Thus, we need to make sure we're using a julong for intermediate
2608       // calculations.
2609       julong initHeapSize;
2610       julong total_memory = os::physical_memory();
2611 
2612       if (total_memory < (julong)256*M) {
2613         jio_fprintf(defaultStream::error_stream(),
2614                     "You need at least 256mb of memory to use -XX:+AggressiveHeap\n");
2615         vm_exit(1);
2616       }
2617 
2618       // The heap size is half of available memory, or (at most)
2619       // all of possible memory less 160mb (leaving room for the OS
2620       // when using ISM).  This is the maximum; because adaptive sizing
2621       // is turned on below, the actual space used may be smaller.
2622 
2623       initHeapSize = MIN2(total_memory / (julong)2,
2624                           total_memory - (julong)160*M);
2625 
2626       initHeapSize = limit_by_allocatable_memory(initHeapSize);
2627 
2628       if (FLAG_IS_DEFAULT(MaxHeapSize)) {
2629          FLAG_SET_CMDLINE(uintx, MaxHeapSize, initHeapSize);
2630          FLAG_SET_CMDLINE(uintx, InitialHeapSize, initHeapSize);
2631          // Currently the minimum size and the initial heap sizes are the same.
2632          set_min_heap_size(initHeapSize);
2633       }
2634       if (FLAG_IS_DEFAULT(NewSize)) {
2635          // Make the young generation 3/8ths of the total heap.
2636          FLAG_SET_CMDLINE(uintx, NewSize,
2637                                 ((julong)MaxHeapSize / (julong)8) * (julong)3);
2638          FLAG_SET_CMDLINE(uintx, MaxNewSize, NewSize);
2639       }
2640 
2641 #ifndef _ALLBSD_SOURCE  // UseLargePages is not yet supported on BSD.
2642       FLAG_SET_DEFAULT(UseLargePages, true);
2643 #endif
2644 
2645       // Increase some data structure sizes for efficiency
2646       FLAG_SET_CMDLINE(uintx, BaseFootPrintEstimate, MaxHeapSize);
2647       FLAG_SET_CMDLINE(bool, ResizeTLAB, false);
2648       FLAG_SET_CMDLINE(uintx, TLABSize, 256*K);
2649 
2650       // See the OldPLABSize comment below, but replace 'after promotion'
2651       // with 'after copying'.  YoungPLABSize is the size of the survivor
2652       // space per-gc-thread buffers.  The default is 4kw.
2653       FLAG_SET_CMDLINE(uintx, YoungPLABSize, 256*K);      // Note: this is in words
2654 
2655       // OldPLABSize is the size of the buffers in the old gen that
2656       // UseParallelGC uses to promote live data that doesn't fit in the
2657       // survivor spaces.  At any given time, there's one for each gc thread.
2658       // The default size is 1kw. These buffers are rarely used, since the
2659       // survivor spaces are usually big enough.  For specjbb, however, there
2660       // are occasions when there's lots of live data in the young gen
2661       // and we end up promoting some of it.  We don't have a definite
2662       // explanation for why bumping OldPLABSize helps, but the theory
2663       // is that a bigger PLAB results in retaining something like the
2664       // original allocation order after promotion, which improves mutator
2665       // locality.  A minor effect may be that larger PLABs reduce the
2666       // number of PLAB allocation events during gc.  The value of 8kw
2667       // was arrived at by experimenting with specjbb.
2668       FLAG_SET_CMDLINE(uintx, OldPLABSize, 8*K);  // Note: this is in words
2669 
2670       // Enable parallel GC and adaptive generation sizing
2671       FLAG_SET_CMDLINE(bool, UseParallelGC, true);
2672       FLAG_SET_DEFAULT(ParallelGCThreads,
2673                        Abstract_VM_Version::parallel_worker_threads());
2674 
2675       // Encourage steady state memory management
2676       FLAG_SET_CMDLINE(uintx, ThresholdTolerance, 100);
2677 
2678       // This appears to improve mutator locality
2679       FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
2680 
2681       // Get around early Solaris scheduling bug
2682       // (affinity vs other jobs on system)
2683       // but disallow DR and offlining (5008695).
2684       FLAG_SET_CMDLINE(bool, BindGCTaskThreadsToCPUs, true);
2685 
2686     } else if (match_option(option, "-XX:+NeverTenure", &tail)) {
2687       // The last option must always win.
2688       FLAG_SET_CMDLINE(bool, AlwaysTenure, false);
2689       FLAG_SET_CMDLINE(bool, NeverTenure, true);
2690     } else if (match_option(option, "-XX:+AlwaysTenure", &tail)) {
2691       // The last option must always win.
2692       FLAG_SET_CMDLINE(bool, NeverTenure, false);
2693       FLAG_SET_CMDLINE(bool, AlwaysTenure, true);
2694     } else if (match_option(option, "-XX:+CMSPermGenSweepingEnabled", &tail) ||
2695                match_option(option, "-XX:-CMSPermGenSweepingEnabled", &tail)) {
2696       jio_fprintf(defaultStream::error_stream(),
2697         "Please use CMSClassUnloadingEnabled in place of "
2698         "CMSPermGenSweepingEnabled in the future\n");
2699     } else if (match_option(option, "-XX:+UseGCTimeLimit", &tail)) {
2700       FLAG_SET_CMDLINE(bool, UseGCOverheadLimit, true);
2701       jio_fprintf(defaultStream::error_stream(),
2702         "Please use -XX:+UseGCOverheadLimit in place of "
2703         "-XX:+UseGCTimeLimit in the future\n");
2704     } else if (match_option(option, "-XX:-UseGCTimeLimit", &tail)) {
2705       FLAG_SET_CMDLINE(bool, UseGCOverheadLimit, false);
2706       jio_fprintf(defaultStream::error_stream(),
2707         "Please use -XX:-UseGCOverheadLimit in place of "
2708         "-XX:-UseGCTimeLimit in the future\n");
2709     // The TLE options are for compatibility with 1.3 and will be
2710     // removed without notice in a future release.  These options
2711     // are not to be documented.
2712     } else if (match_option(option, "-XX:MaxTLERatio=", &tail)) {
2713       // No longer used.
2714     } else if (match_option(option, "-XX:+ResizeTLE", &tail)) {
2715       FLAG_SET_CMDLINE(bool, ResizeTLAB, true);
2716     } else if (match_option(option, "-XX:-ResizeTLE", &tail)) {
2717       FLAG_SET_CMDLINE(bool, ResizeTLAB, false);
2718     } else if (match_option(option, "-XX:+PrintTLE", &tail)) {
2719       FLAG_SET_CMDLINE(bool, PrintTLAB, true);
2720     } else if (match_option(option, "-XX:-PrintTLE", &tail)) {
2721       FLAG_SET_CMDLINE(bool, PrintTLAB, false);
2722     } else if (match_option(option, "-XX:TLEFragmentationRatio=", &tail)) {
2723       // No longer used.
2724     } else if (match_option(option, "-XX:TLESize=", &tail)) {
2725       julong long_tlab_size = 0;
2726       ArgsRange errcode = parse_memory_size(tail, &long_tlab_size, 1);
2727       if (errcode != arg_in_range) {
2728         jio_fprintf(defaultStream::error_stream(),
2729                     "Invalid TLAB size: %s\n", option->optionString);
2730         describe_range_error(errcode);
2731         return JNI_EINVAL;
2732       }
2733       FLAG_SET_CMDLINE(uintx, TLABSize, long_tlab_size);
2734     } else if (match_option(option, "-XX:TLEThreadRatio=", &tail)) {
2735       // No longer used.
2736     } else if (match_option(option, "-XX:+UseTLE", &tail)) {
2737       FLAG_SET_CMDLINE(bool, UseTLAB, true);
2738     } else if (match_option(option, "-XX:-UseTLE", &tail)) {
2739       FLAG_SET_CMDLINE(bool, UseTLAB, false);
2740 SOLARIS_ONLY(
2741     } else if (match_option(option, "-XX:+UsePermISM", &tail)) {
2742       warning("-XX:+UsePermISM is obsolete.");
2743       FLAG_SET_CMDLINE(bool, UseISM, true);
2744     } else if (match_option(option, "-XX:-UsePermISM", &tail)) {
2745       FLAG_SET_CMDLINE(bool, UseISM, false);
2746 )
2747     } else if (match_option(option, "-XX:+DisplayVMOutputToStderr", &tail)) {
2748       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, false);
2749       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, true);
2750     } else if (match_option(option, "-XX:+DisplayVMOutputToStdout", &tail)) {
2751       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, false);
2752       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, true);
2753     } else if (match_option(option, "-XX:+ExtendedDTraceProbes", &tail)) {
2754 #if defined(DTRACE_ENABLED)
2755       FLAG_SET_CMDLINE(bool, ExtendedDTraceProbes, true);
2756       FLAG_SET_CMDLINE(bool, DTraceMethodProbes, true);
2757       FLAG_SET_CMDLINE(bool, DTraceAllocProbes, true);
2758       FLAG_SET_CMDLINE(bool, DTraceMonitorProbes, true);
2759 #else // defined(DTRACE_ENABLED)
2760       jio_fprintf(defaultStream::error_stream(),
2761                   "ExtendedDTraceProbes flag is not applicable for this configuration\n");
2762       return JNI_EINVAL;
2763 #endif // defined(DTRACE_ENABLED)
2764 #ifdef ASSERT
2765     } else if (match_option(option, "-XX:+FullGCALot", &tail)) {
2766       FLAG_SET_CMDLINE(bool, FullGCALot, true);
2767       // disable scavenge before parallel mark-compact
2768       FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
2769 #endif
2770     } else if (match_option(option, "-XX:CMSParPromoteBlocksToClaim=", &tail)) {
2771       julong cms_blocks_to_claim = (julong)atol(tail);
2772       FLAG_SET_CMDLINE(uintx, CMSParPromoteBlocksToClaim, cms_blocks_to_claim);
2773       jio_fprintf(defaultStream::error_stream(),
2774         "Please use -XX:OldPLABSize in place of "
2775         "-XX:CMSParPromoteBlocksToClaim in the future\n");
2776     } else if (match_option(option, "-XX:ParCMSPromoteBlocksToClaim=", &tail)) {
2777       julong cms_blocks_to_claim = (julong)atol(tail);
2778       FLAG_SET_CMDLINE(uintx, CMSParPromoteBlocksToClaim, cms_blocks_to_claim);
2779       jio_fprintf(defaultStream::error_stream(),
2780         "Please use -XX:OldPLABSize in place of "
2781         "-XX:ParCMSPromoteBlocksToClaim in the future\n");
2782     } else if (match_option(option, "-XX:ParallelGCOldGenAllocBufferSize=", &tail)) {
2783       julong old_plab_size = 0;
2784       ArgsRange errcode = parse_memory_size(tail, &old_plab_size, 1);
2785       if (errcode != arg_in_range) {
2786         jio_fprintf(defaultStream::error_stream(),
2787                     "Invalid old PLAB size: %s\n", option->optionString);
2788         describe_range_error(errcode);
2789         return JNI_EINVAL;
2790       }
2791       FLAG_SET_CMDLINE(uintx, OldPLABSize, old_plab_size);
2792       jio_fprintf(defaultStream::error_stream(),
2793                   "Please use -XX:OldPLABSize in place of "
2794                   "-XX:ParallelGCOldGenAllocBufferSize in the future\n");
2795     } else if (match_option(option, "-XX:ParallelGCToSpaceAllocBufferSize=", &tail)) {
2796       julong young_plab_size = 0;
2797       ArgsRange errcode = parse_memory_size(tail, &young_plab_size, 1);
2798       if (errcode != arg_in_range) {
2799         jio_fprintf(defaultStream::error_stream(),
2800                     "Invalid young PLAB size: %s\n", option->optionString);
2801         describe_range_error(errcode);
2802         return JNI_EINVAL;
2803       }
2804       FLAG_SET_CMDLINE(uintx, YoungPLABSize, young_plab_size);
2805       jio_fprintf(defaultStream::error_stream(),
2806                   "Please use -XX:YoungPLABSize in place of "
2807                   "-XX:ParallelGCToSpaceAllocBufferSize in the future\n");
2808     } else if (match_option(option, "-XX:CMSMarkStackSize=", &tail) ||
2809                match_option(option, "-XX:G1MarkStackSize=", &tail)) {
2810       julong stack_size = 0;
2811       ArgsRange errcode = parse_memory_size(tail, &stack_size, 1);
2812       if (errcode != arg_in_range) {
2813         jio_fprintf(defaultStream::error_stream(),
2814                     "Invalid mark stack size: %s\n", option->optionString);
2815         describe_range_error(errcode);
2816         return JNI_EINVAL;
2817       }
2818       FLAG_SET_CMDLINE(uintx, MarkStackSize, stack_size);
2819     } else if (match_option(option, "-XX:CMSMarkStackSizeMax=", &tail)) {
2820       julong max_stack_size = 0;
2821       ArgsRange errcode = parse_memory_size(tail, &max_stack_size, 1);
2822       if (errcode != arg_in_range) {
2823         jio_fprintf(defaultStream::error_stream(),
2824                     "Invalid maximum mark stack size: %s\n",
2825                     option->optionString);
2826         describe_range_error(errcode);
2827         return JNI_EINVAL;
2828       }
2829       FLAG_SET_CMDLINE(uintx, MarkStackSizeMax, max_stack_size);
2830     } else if (match_option(option, "-XX:ParallelMarkingThreads=", &tail) ||
2831                match_option(option, "-XX:ParallelCMSThreads=", &tail)) {
2832       uintx conc_threads = 0;
2833       if (!parse_uintx(tail, &conc_threads, 1)) {
2834         jio_fprintf(defaultStream::error_stream(),
2835                     "Invalid concurrent threads: %s\n", option->optionString);
2836         return JNI_EINVAL;
2837       }
2838       FLAG_SET_CMDLINE(uintx, ConcGCThreads, conc_threads);
2839     } else if (match_option(option, "-XX:MaxDirectMemorySize=", &tail)) {
2840       julong max_direct_memory_size = 0;
2841       ArgsRange errcode = parse_memory_size(tail, &max_direct_memory_size, 0);
2842       if (errcode != arg_in_range) {
2843         jio_fprintf(defaultStream::error_stream(),
2844                     "Invalid maximum direct memory size: %s\n",
2845                     option->optionString);
2846         describe_range_error(errcode);
2847         return JNI_EINVAL;
2848       }
2849       FLAG_SET_CMDLINE(uintx, MaxDirectMemorySize, max_direct_memory_size);
2850     } else if (match_option(option, "-XX:+UseVMInterruptibleIO", &tail)) {
2851       // NOTE! In JDK 9, the UseVMInterruptibleIO flag will completely go
2852       //       away and will cause VM initialization failures!
2853       warning("-XX:+UseVMInterruptibleIO is obsolete and will be removed in a future release.");
2854       FLAG_SET_CMDLINE(bool, UseVMInterruptibleIO, true);
2855 #if !INCLUDE_MANAGEMENT
2856     } else if (match_option(option, "-XX:+ManagementServer", &tail)) {
2857         jio_fprintf(defaultStream::error_stream(),
2858           "ManagementServer is not supported in this VM.\n");
2859         return JNI_ERR;
2860 #endif // INCLUDE_MANAGEMENT
2861     } else if (match_option(option, "-XX:", &tail)) { // -XX:xxxx
2862       // Skip -XX:Flags= since that case has already been handled
2863       if (strncmp(tail, "Flags=", strlen("Flags=")) != 0) {
2864         if (!process_argument(tail, args->ignoreUnrecognized, origin)) {
2865           return JNI_EINVAL;
2866         }
2867       }
2868     // Unknown option
2869     } else if (is_bad_option(option, args->ignoreUnrecognized)) {
2870       return JNI_ERR;
2871     }
2872   }
2873 
2874   // Change the default value for flags  which have different default values
2875   // when working with older JDKs.
2876 #ifdef LINUX
2877  if (JDK_Version::current().compare_major(6) <= 0 &&
2878       FLAG_IS_DEFAULT(UseLinuxPosixThreadCPUClocks)) {
2879     FLAG_SET_DEFAULT(UseLinuxPosixThreadCPUClocks, false);
2880   }
2881 #endif // LINUX
2882   return JNI_OK;
2883 }
2884 
2885 jint Arguments::finalize_vm_init_args(SysClassPath* scp_p, bool scp_assembly_required) {
2886   // This must be done after all -D arguments have been processed.
2887   scp_p->expand_endorsed();
2888 
2889   if (scp_assembly_required || scp_p->get_endorsed() != NULL) {
2890     // Assemble the bootclasspath elements into the final path.
2891     Arguments::set_sysclasspath(scp_p->combined_path());
2892   }
2893 
2894   // This must be done after all arguments have been processed.
2895   // java_compiler() true means set to "NONE" or empty.
2896   if (java_compiler() && !xdebug_mode()) {
2897     // For backwards compatibility, we switch to interpreted mode if
2898     // -Djava.compiler="NONE" or "" is specified AND "-Xdebug" was
2899     // not specified.
2900     set_mode_flags(_int);
2901   }
2902   if (CompileThreshold == 0) {
2903     set_mode_flags(_int);
2904   }
2905 
2906 #ifndef COMPILER2
2907   // Don't degrade server performance for footprint
2908   if (FLAG_IS_DEFAULT(UseLargePages) &&
2909       MaxHeapSize < LargePageHeapSizeThreshold) {
2910     // No need for large granularity pages w/small heaps.
2911     // Note that large pages are enabled/disabled for both the
2912     // Java heap and the code cache.
2913     FLAG_SET_DEFAULT(UseLargePages, false);
2914     SOLARIS_ONLY(FLAG_SET_DEFAULT(UseMPSS, false));
2915     SOLARIS_ONLY(FLAG_SET_DEFAULT(UseISM, false));
2916   }
2917 
2918   // Tiered compilation is undefined with C1.
2919   TieredCompilation = false;
2920 #else
2921   if (!FLAG_IS_DEFAULT(OptoLoopAlignment) && FLAG_IS_DEFAULT(MaxLoopPad)) {
2922     FLAG_SET_DEFAULT(MaxLoopPad, OptoLoopAlignment-1);
2923   }
2924 #endif
2925 
2926   // If we are running in a headless jre, force java.awt.headless property
2927   // to be true unless the property has already been set.
2928   // Also allow the OS environment variable JAVA_AWT_HEADLESS to set headless state.
2929   if (os::is_headless_jre()) {
2930     const char* headless = Arguments::get_property("java.awt.headless");
2931     if (headless == NULL) {
2932       char envbuffer[128];
2933       if (!os::getenv("JAVA_AWT_HEADLESS", envbuffer, sizeof(envbuffer))) {
2934         if (!add_property("java.awt.headless=true")) {
2935           return JNI_ENOMEM;
2936         }
2937       } else {
2938         char buffer[256];
2939         strcpy(buffer, "java.awt.headless=");
2940         strcat(buffer, envbuffer);
2941         if (!add_property(buffer)) {
2942           return JNI_ENOMEM;
2943         }
2944       }
2945     }
2946   }
2947 
2948   if (!check_vm_args_consistency()) {
2949     return JNI_ERR;
2950   }
2951 
2952   return JNI_OK;
2953 }
2954 
2955 jint Arguments::parse_java_options_environment_variable(SysClassPath* scp_p, bool* scp_assembly_required_p) {
2956   return parse_options_environment_variable("_JAVA_OPTIONS", scp_p,
2957                                             scp_assembly_required_p);
2958 }
2959 
2960 jint Arguments::parse_java_tool_options_environment_variable(SysClassPath* scp_p, bool* scp_assembly_required_p) {
2961   return parse_options_environment_variable("JAVA_TOOL_OPTIONS", scp_p,
2962                                             scp_assembly_required_p);
2963 }
2964 
2965 jint Arguments::parse_options_environment_variable(const char* name, SysClassPath* scp_p, bool* scp_assembly_required_p) {
2966   const int N_MAX_OPTIONS = 64;
2967   const int OPTION_BUFFER_SIZE = 1024;
2968   char buffer[OPTION_BUFFER_SIZE];
2969 
2970   // The variable will be ignored if it exceeds the length of the buffer.
2971   // Don't check this variable if user has special privileges
2972   // (e.g. unix su command).
2973   if (os::getenv(name, buffer, sizeof(buffer)) &&
2974       !os::have_special_privileges()) {
2975     JavaVMOption options[N_MAX_OPTIONS];      // Construct option array
2976     jio_fprintf(defaultStream::error_stream(),
2977                 "Picked up %s: %s\n", name, buffer);
2978     char* rd = buffer;                        // pointer to the input string (rd)
2979     int i;
2980     for (i = 0; i < N_MAX_OPTIONS;) {         // repeat for all options in the input string
2981       while (isspace(*rd)) rd++;              // skip whitespace
2982       if (*rd == 0) break;                    // we re done when the input string is read completely
2983 
2984       // The output, option string, overwrites the input string.
2985       // Because of quoting, the pointer to the option string (wrt) may lag the pointer to
2986       // input string (rd).
2987       char* wrt = rd;
2988 
2989       options[i++].optionString = wrt;        // Fill in option
2990       while (*rd != 0 && !isspace(*rd)) {     // unquoted strings terminate with a space or NULL
2991         if (*rd == '\'' || *rd == '"') {      // handle a quoted string
2992           int quote = *rd;                    // matching quote to look for
2993           rd++;                               // don't copy open quote
2994           while (*rd != quote) {              // include everything (even spaces) up until quote
2995             if (*rd == 0) {                   // string termination means unmatched string
2996               jio_fprintf(defaultStream::error_stream(),
2997                           "Unmatched quote in %s\n", name);
2998               return JNI_ERR;
2999             }
3000             *wrt++ = *rd++;                   // copy to option string
3001           }
3002           rd++;                               // don't copy close quote
3003         } else {
3004           *wrt++ = *rd++;                     // copy to option string
3005         }
3006       }
3007       // Need to check if we're done before writing a NULL,
3008       // because the write could be to the byte that rd is pointing to.
3009       if (*rd++ == 0) {
3010         *wrt = 0;
3011         break;
3012       }
3013       *wrt = 0;                               // Zero terminate option
3014     }
3015     // Construct JavaVMInitArgs structure and parse as if it was part of the command line
3016     JavaVMInitArgs vm_args;
3017     vm_args.version = JNI_VERSION_1_2;
3018     vm_args.options = options;
3019     vm_args.nOptions = i;
3020     vm_args.ignoreUnrecognized = IgnoreUnrecognizedVMOptions;
3021 
3022     if (PrintVMOptions) {
3023       const char* tail;
3024       for (int i = 0; i < vm_args.nOptions; i++) {
3025         const JavaVMOption *option = vm_args.options + i;
3026         if (match_option(option, "-XX:", &tail)) {
3027           logOption(tail);
3028         }
3029       }
3030     }
3031 
3032     return(parse_each_vm_init_arg(&vm_args, scp_p, scp_assembly_required_p, ENVIRON_VAR));
3033   }
3034   return JNI_OK;
3035 }
3036 
3037 void Arguments::set_shared_spaces_flags() {
3038   const bool must_share = DumpSharedSpaces || RequireSharedSpaces;
3039   const bool might_share = must_share || UseSharedSpaces;
3040 
3041   // CompressedOops cannot be used with CDS.  The offsets of oopmaps and
3042   // static fields are incorrect in the archive.  With some more clever
3043   // initialization, this restriction can probably be lifted.
3044   // ??? UseLargePages might be okay now
3045   const bool cannot_share = UseCompressedOops ||
3046                             (UseLargePages && FLAG_IS_CMDLINE(UseLargePages));
3047   if (cannot_share) {
3048     if (must_share) {
3049         warning("disabling large pages %s"
3050                 "because of %s", "" LP64_ONLY("and compressed oops "),
3051                 DumpSharedSpaces ? "-Xshare:dump" : "-Xshare:on");
3052         FLAG_SET_CMDLINE(bool, UseLargePages, false);
3053         LP64_ONLY(FLAG_SET_CMDLINE(bool, UseCompressedOops, false));
3054         LP64_ONLY(FLAG_SET_CMDLINE(bool, UseCompressedKlassPointers, false));
3055     } else {
3056       // Prefer compressed oops and large pages to class data sharing
3057       if (UseSharedSpaces && Verbose) {
3058         warning("turning off use of shared archive because of large pages%s",
3059                  "" LP64_ONLY(" and/or compressed oops"));
3060       }
3061       no_shared_spaces();
3062     }
3063   } else if (UseLargePages && might_share) {
3064     // Disable large pages to allow shared spaces.  This is sub-optimal, since
3065     // there may not even be a shared archive to use.
3066     FLAG_SET_DEFAULT(UseLargePages, false);
3067   }
3068 
3069   if (DumpSharedSpaces) {
3070     if (RequireSharedSpaces) {
3071       warning("cannot dump shared archive while using shared archive");
3072     }
3073     UseSharedSpaces = false;
3074   }
3075 }
3076 
3077 // Disable options not supported in this release, with a warning if they
3078 // were explicitly requested on the command-line
3079 #define UNSUPPORTED_OPTION(opt, description)                    \
3080 do {                                                            \
3081   if (opt) {                                                    \
3082     if (FLAG_IS_CMDLINE(opt)) {                                 \
3083       warning(description " is disabled in this release.");     \
3084     }                                                           \
3085     FLAG_SET_DEFAULT(opt, false);                               \
3086   }                                                             \
3087 } while(0)
3088 
3089 
3090 #define UNSUPPORTED_GC_OPTION(gc)                                     \
3091 do {                                                                  \
3092   if (gc) {                                                           \
3093     if (FLAG_IS_CMDLINE(gc)) {                                        \
3094       warning(#gc " is not supported in this VM.  Using Serial GC."); \
3095     }                                                                 \
3096     FLAG_SET_DEFAULT(gc, false);                                      \
3097   }                                                                   \
3098 } while(0)
3099 
3100 #if !INCLUDE_ALL_GCS
3101 static void force_serial_gc() {
3102   FLAG_SET_DEFAULT(UseSerialGC, true);
3103   FLAG_SET_DEFAULT(CMSIncrementalMode, false);  // special CMS suboption
3104   UNSUPPORTED_GC_OPTION(UseG1GC);
3105   UNSUPPORTED_GC_OPTION(UseParallelGC);
3106   UNSUPPORTED_GC_OPTION(UseParallelOldGC);
3107   UNSUPPORTED_GC_OPTION(UseConcMarkSweepGC);
3108   UNSUPPORTED_GC_OPTION(UseParNewGC);
3109 }
3110 #endif // INCLUDE_ALL_GCS
3111 
3112 // Parse entry point called from JNI_CreateJavaVM
3113 
3114 jint Arguments::parse(const JavaVMInitArgs* args) {
3115 
3116   // Sharing support
3117   // Construct the path to the archive
3118   char jvm_path[JVM_MAXPATHLEN];
3119   os::jvm_path(jvm_path, sizeof(jvm_path));
3120   char *end = strrchr(jvm_path, *os::file_separator());
3121   if (end != NULL) *end = '\0';
3122   char *shared_archive_path = NEW_C_HEAP_ARRAY(char, strlen(jvm_path) +
3123       strlen(os::file_separator()) + 20, mtInternal);
3124   if (shared_archive_path == NULL) return JNI_ENOMEM;
3125   strcpy(shared_archive_path, jvm_path);
3126   strcat(shared_archive_path, os::file_separator());
3127   strcat(shared_archive_path, "classes");
3128   strcat(shared_archive_path, ".jsa");
3129   SharedArchivePath = shared_archive_path;
3130 
3131   // Remaining part of option string
3132   const char* tail;
3133 
3134   // If flag "-XX:Flags=flags-file" is used it will be the first option to be processed.
3135   const char* hotspotrc = ".hotspotrc";
3136   bool settings_file_specified = false;
3137   bool needs_hotspotrc_warning = false;
3138 
3139   const char* flags_file;
3140   int index;
3141   for (index = 0; index < args->nOptions; index++) {
3142     const JavaVMOption *option = args->options + index;
3143     if (match_option(option, "-XX:Flags=", &tail)) {
3144       flags_file = tail;
3145       settings_file_specified = true;
3146     }
3147     if (match_option(option, "-XX:+PrintVMOptions", &tail)) {
3148       PrintVMOptions = true;
3149     }
3150     if (match_option(option, "-XX:-PrintVMOptions", &tail)) {
3151       PrintVMOptions = false;
3152     }
3153     if (match_option(option, "-XX:+IgnoreUnrecognizedVMOptions", &tail)) {
3154       IgnoreUnrecognizedVMOptions = true;
3155     }
3156     if (match_option(option, "-XX:-IgnoreUnrecognizedVMOptions", &tail)) {
3157       IgnoreUnrecognizedVMOptions = false;
3158     }
3159     if (match_option(option, "-XX:+PrintFlagsInitial", &tail)) {
3160       CommandLineFlags::printFlags(tty, false);
3161       vm_exit(0);
3162     }
3163     if (match_option(option, "-XX:NativeMemoryTracking", &tail)) {
3164 #if INCLUDE_NMT
3165       MemTracker::init_tracking_options(tail);
3166 #else
3167       jio_fprintf(defaultStream::error_stream(),
3168         "Native Memory Tracking is not supported in this VM\n");
3169       return JNI_ERR;
3170 #endif
3171     }
3172 
3173 
3174 #ifndef PRODUCT
3175     if (match_option(option, "-XX:+PrintFlagsWithComments", &tail)) {
3176       CommandLineFlags::printFlags(tty, true);
3177       vm_exit(0);
3178     }
3179 #endif
3180   }
3181 
3182   if (IgnoreUnrecognizedVMOptions) {
3183     // uncast const to modify the flag args->ignoreUnrecognized
3184     *(jboolean*)(&args->ignoreUnrecognized) = true;
3185   }
3186 
3187   // Parse specified settings file
3188   if (settings_file_specified) {
3189     if (!process_settings_file(flags_file, true, args->ignoreUnrecognized)) {
3190       return JNI_EINVAL;
3191     }
3192   } else {
3193 #ifdef ASSERT
3194     // Parse default .hotspotrc settings file
3195     if (!process_settings_file(".hotspotrc", false, args->ignoreUnrecognized)) {
3196       return JNI_EINVAL;
3197     }
3198 #else
3199     struct stat buf;
3200     if (os::stat(hotspotrc, &buf) == 0) {
3201       needs_hotspotrc_warning = true;
3202     }
3203 #endif
3204   }
3205 
3206   if (PrintVMOptions) {
3207     for (index = 0; index < args->nOptions; index++) {
3208       const JavaVMOption *option = args->options + index;
3209       if (match_option(option, "-XX:", &tail)) {
3210         logOption(tail);
3211       }
3212     }
3213   }
3214 
3215   // Parse JavaVMInitArgs structure passed in, as well as JAVA_TOOL_OPTIONS and _JAVA_OPTIONS
3216   jint result = parse_vm_init_args(args);
3217   if (result != JNI_OK) {
3218     return result;
3219   }
3220 
3221   // Delay warning until here so that we've had a chance to process
3222   // the -XX:-PrintWarnings flag
3223   if (needs_hotspotrc_warning) {
3224     warning("%s file is present but has been ignored.  "
3225             "Run with -XX:Flags=%s to load the file.",
3226             hotspotrc, hotspotrc);
3227   }
3228 
3229 #ifdef _ALLBSD_SOURCE  // UseLargePages is not yet supported on BSD.
3230   UNSUPPORTED_OPTION(UseLargePages, "-XX:+UseLargePages");
3231 #endif
3232 
3233 #if INCLUDE_ALL_GCS
3234   #if (defined JAVASE_EMBEDDED || defined ARM)
3235     UNSUPPORTED_OPTION(UseG1GC, "G1 GC");
3236   #endif
3237 #endif
3238 
3239 #ifndef PRODUCT
3240   if (TraceBytecodesAt != 0) {
3241     TraceBytecodes = true;
3242   }
3243   if (CountCompiledCalls) {
3244     if (UseCounterDecay) {
3245       warning("UseCounterDecay disabled because CountCalls is set");
3246       UseCounterDecay = false;
3247     }
3248   }
3249 #endif // PRODUCT
3250 
3251   // JSR 292 is not supported before 1.7
3252   if (!JDK_Version::is_gte_jdk17x_version()) {
3253     if (EnableInvokeDynamic) {
3254       if (!FLAG_IS_DEFAULT(EnableInvokeDynamic)) {
3255         warning("JSR 292 is not supported before 1.7.  Disabling support.");
3256       }
3257       EnableInvokeDynamic = false;
3258     }
3259   }
3260 
3261   if (EnableInvokeDynamic && ScavengeRootsInCode == 0) {
3262     if (!FLAG_IS_DEFAULT(ScavengeRootsInCode)) {
3263       warning("forcing ScavengeRootsInCode non-zero because EnableInvokeDynamic is true");
3264     }
3265     ScavengeRootsInCode = 1;
3266   }
3267 
3268   if (PrintGCDetails) {
3269     // Turn on -verbose:gc options as well
3270     PrintGC = true;
3271   }
3272 
3273   if (!JDK_Version::is_gte_jdk18x_version()) {
3274     // To avoid changing the log format for 7 updates this flag is only
3275     // true by default in JDK8 and above.
3276     if (FLAG_IS_DEFAULT(PrintGCCause)) {
3277       FLAG_SET_DEFAULT(PrintGCCause, false);
3278     }
3279   }
3280 
3281   // Set object alignment values.
3282   set_object_alignment();
3283 
3284 #if !INCLUDE_ALL_GCS
3285   force_serial_gc();
3286 #endif // INCLUDE_ALL_GCS
3287 #if !INCLUDE_CDS
3288   if (DumpSharedSpaces || RequireSharedSpaces) {
3289     jio_fprintf(defaultStream::error_stream(),
3290       "Shared spaces are not supported in this VM\n");
3291     return JNI_ERR;
3292   }
3293   if ((UseSharedSpaces && FLAG_IS_CMDLINE(UseSharedSpaces)) || PrintSharedSpaces) {
3294     warning("Shared spaces are not supported in this VM");
3295     FLAG_SET_DEFAULT(UseSharedSpaces, false);
3296     FLAG_SET_DEFAULT(PrintSharedSpaces, false);
3297   }
3298   no_shared_spaces();
3299 #endif // INCLUDE_CDS
3300 
3301   // Set flags based on ergonomics.
3302   set_ergonomics_flags();
3303 
3304   set_shared_spaces_flags();
3305 
3306   // Check the GC selections again.
3307   if (!check_gc_consistency()) {
3308     return JNI_EINVAL;
3309   }
3310 
3311   if (TieredCompilation) {
3312     set_tiered_flags();
3313   } else {
3314     // Check if the policy is valid. Policies 0 and 1 are valid for non-tiered setup.
3315     if (CompilationPolicyChoice >= 2) {
3316       vm_exit_during_initialization(
3317         "Incompatible compilation policy selected", NULL);
3318     }
3319   }
3320 
3321   // Set heap size based on available physical memory
3322   set_heap_size();
3323 
3324 #if INCLUDE_ALL_GCS
3325   // Set per-collector flags
3326   if (UseParallelGC || UseParallelOldGC) {
3327     set_parallel_gc_flags();
3328   } else if (UseConcMarkSweepGC) { // should be done before ParNew check below
3329     set_cms_and_parnew_gc_flags();
3330   } else if (UseParNewGC) {  // skipped if CMS is set above
3331     set_parnew_gc_flags();
3332   } else if (UseG1GC) {
3333     set_g1_gc_flags();
3334   }
3335   check_deprecated_gcs();
3336   check_deprecated_gc_flags();
3337   if (AssumeMP && !UseSerialGC) {
3338     if (FLAG_IS_DEFAULT(ParallelGCThreads) && ParallelGCThreads == 1) {
3339       warning("If the number of processors is expected to increase from one, then"
3340               " you should configure the number of parallel GC threads appropriately"
3341               " using -XX:ParallelGCThreads=N");
3342     }
3343   }
3344 #else // INCLUDE_ALL_GCS
3345   assert(verify_serial_gc_flags(), "SerialGC unset");
3346 #endif // INCLUDE_ALL_GCS
3347 
3348   // Set bytecode rewriting flags
3349   set_bytecode_flags();
3350 
3351   // Set flags if Aggressive optimization flags (-XX:+AggressiveOpts) enabled.
3352   set_aggressive_opts_flags();
3353 
3354   // Turn off biased locking for locking debug mode flags,
3355   // which are subtlely different from each other but neither works with
3356   // biased locking.
3357   if (UseHeavyMonitors
3358 #ifdef COMPILER1
3359       || !UseFastLocking
3360 #endif // COMPILER1
3361     ) {
3362     if (!FLAG_IS_DEFAULT(UseBiasedLocking) && UseBiasedLocking) {
3363       // flag set to true on command line; warn the user that they
3364       // can't enable biased locking here
3365       warning("Biased Locking is not supported with locking debug flags"
3366               "; ignoring UseBiasedLocking flag." );
3367     }
3368     UseBiasedLocking = false;
3369   }
3370 
3371 #ifdef CC_INTERP
3372   // Clear flags not supported by the C++ interpreter
3373   FLAG_SET_DEFAULT(ProfileInterpreter, false);
3374   FLAG_SET_DEFAULT(UseBiasedLocking, false);
3375   LP64_ONLY(FLAG_SET_DEFAULT(UseCompressedOops, false));
3376   LP64_ONLY(FLAG_SET_DEFAULT(UseCompressedKlassPointers, false));
3377 #endif // CC_INTERP
3378 
3379 #ifdef COMPILER2
3380   if (!UseBiasedLocking || EmitSync != 0) {
3381     UseOptoBiasInlining = false;
3382   }
3383   if (!EliminateLocks) {
3384     EliminateNestedLocks = false;
3385   }
3386   if (!Inline) {
3387     IncrementalInline = false;
3388   }
3389 #ifndef PRODUCT
3390   if (!IncrementalInline) {
3391     AlwaysIncrementalInline = false;
3392   }
3393 #endif
3394   if (IncrementalInline && FLAG_IS_DEFAULT(MaxNodeLimit)) {
3395     // incremental inlining: bump MaxNodeLimit
3396     FLAG_SET_DEFAULT(MaxNodeLimit, (intx)75000);
3397   }
3398 #endif
3399 
3400   if (PrintAssembly && FLAG_IS_DEFAULT(DebugNonSafepoints)) {
3401     warning("PrintAssembly is enabled; turning on DebugNonSafepoints to gain additional output");
3402     DebugNonSafepoints = true;
3403   }
3404 
3405 #ifndef PRODUCT
3406   if (CompileTheWorld) {
3407     // Force NmethodSweeper to sweep whole CodeCache each time.
3408     if (FLAG_IS_DEFAULT(NmethodSweepFraction)) {
3409       NmethodSweepFraction = 1;
3410     }
3411   }
3412 #endif
3413 
3414   if (PrintCommandLineFlags) {
3415     CommandLineFlags::printSetFlags(tty);
3416   }
3417 
3418   // Apply CPU specific policy for the BiasedLocking
3419   if (UseBiasedLocking) {
3420     if (!VM_Version::use_biased_locking() &&
3421         !(FLAG_IS_CMDLINE(UseBiasedLocking))) {
3422       UseBiasedLocking = false;
3423     }
3424   }
3425 
3426   // set PauseAtExit if the gamma launcher was used and a debugger is attached
3427   // but only if not already set on the commandline
3428   if (Arguments::created_by_gamma_launcher() && os::is_debugger_attached()) {
3429     bool set = false;
3430     CommandLineFlags::wasSetOnCmdline("PauseAtExit", &set);
3431     if (!set) {
3432       FLAG_SET_DEFAULT(PauseAtExit, true);
3433     }
3434   }
3435 
3436   return JNI_OK;
3437 }
3438 
3439 jint Arguments::adjust_after_os() {
3440 #if INCLUDE_ALL_GCS
3441   if (UseParallelGC || UseParallelOldGC) {
3442     if (UseNUMA) {
3443       if (FLAG_IS_DEFAULT(MinHeapDeltaBytes)) {
3444         FLAG_SET_DEFAULT(MinHeapDeltaBytes, 64*M);
3445       }
3446       // For those collectors or operating systems (eg, Windows) that do
3447       // not support full UseNUMA, we will map to UseNUMAInterleaving for now
3448       UseNUMAInterleaving = true;
3449     }
3450   }
3451 #endif // INCLUDE_ALL_GCS
3452   return JNI_OK;
3453 }
3454 
3455 int Arguments::PropertyList_count(SystemProperty* pl) {
3456   int count = 0;
3457   while(pl != NULL) {
3458     count++;
3459     pl = pl->next();
3460   }
3461   return count;
3462 }
3463 
3464 const char* Arguments::PropertyList_get_value(SystemProperty *pl, const char* key) {
3465   assert(key != NULL, "just checking");
3466   SystemProperty* prop;
3467   for (prop = pl; prop != NULL; prop = prop->next()) {
3468     if (strcmp(key, prop->key()) == 0) return prop->value();
3469   }
3470   return NULL;
3471 }
3472 
3473 const char* Arguments::PropertyList_get_key_at(SystemProperty *pl, int index) {
3474   int count = 0;
3475   const char* ret_val = NULL;
3476 
3477   while(pl != NULL) {
3478     if(count >= index) {
3479       ret_val = pl->key();
3480       break;
3481     }
3482     count++;
3483     pl = pl->next();
3484   }
3485 
3486   return ret_val;
3487 }
3488 
3489 char* Arguments::PropertyList_get_value_at(SystemProperty* pl, int index) {
3490   int count = 0;
3491   char* ret_val = NULL;
3492 
3493   while(pl != NULL) {
3494     if(count >= index) {
3495       ret_val = pl->value();
3496       break;
3497     }
3498     count++;
3499     pl = pl->next();
3500   }
3501 
3502   return ret_val;
3503 }
3504 
3505 void Arguments::PropertyList_add(SystemProperty** plist, SystemProperty *new_p) {
3506   SystemProperty* p = *plist;
3507   if (p == NULL) {
3508     *plist = new_p;
3509   } else {
3510     while (p->next() != NULL) {
3511       p = p->next();
3512     }
3513     p->set_next(new_p);
3514   }
3515 }
3516 
3517 void Arguments::PropertyList_add(SystemProperty** plist, const char* k, char* v) {
3518   if (plist == NULL)
3519     return;
3520 
3521   SystemProperty* new_p = new SystemProperty(k, v, true);
3522   PropertyList_add(plist, new_p);
3523 }
3524 
3525 // This add maintains unique property key in the list.
3526 void Arguments::PropertyList_unique_add(SystemProperty** plist, const char* k, char* v, jboolean append) {
3527   if (plist == NULL)
3528     return;
3529 
3530   // If property key exist then update with new value.
3531   SystemProperty* prop;
3532   for (prop = *plist; prop != NULL; prop = prop->next()) {
3533     if (strcmp(k, prop->key()) == 0) {
3534       if (append) {
3535         prop->append_value(v);
3536       } else {
3537         prop->set_value(v);
3538       }
3539       return;
3540     }
3541   }
3542 
3543   PropertyList_add(plist, k, v);
3544 }
3545 
3546 // Copies src into buf, replacing "%%" with "%" and "%p" with pid
3547 // Returns true if all of the source pointed by src has been copied over to
3548 // the destination buffer pointed by buf. Otherwise, returns false.
3549 // Notes:
3550 // 1. If the length (buflen) of the destination buffer excluding the
3551 // NULL terminator character is not long enough for holding the expanded
3552 // pid characters, it also returns false instead of returning the partially
3553 // expanded one.
3554 // 2. The passed in "buflen" should be large enough to hold the null terminator.
3555 bool Arguments::copy_expand_pid(const char* src, size_t srclen,
3556                                 char* buf, size_t buflen) {
3557   const char* p = src;
3558   char* b = buf;
3559   const char* src_end = &src[srclen];
3560   char* buf_end = &buf[buflen - 1];
3561 
3562   while (p < src_end && b < buf_end) {
3563     if (*p == '%') {
3564       switch (*(++p)) {
3565       case '%':         // "%%" ==> "%"
3566         *b++ = *p++;
3567         break;
3568       case 'p':  {       //  "%p" ==> current process id
3569         // buf_end points to the character before the last character so
3570         // that we could write '\0' to the end of the buffer.
3571         size_t buf_sz = buf_end - b + 1;
3572         int ret = jio_snprintf(b, buf_sz, "%d", os::current_process_id());
3573 
3574         // if jio_snprintf fails or the buffer is not long enough to hold
3575         // the expanded pid, returns false.
3576         if (ret < 0 || ret >= (int)buf_sz) {
3577           return false;
3578         } else {
3579           b += ret;
3580           assert(*b == '\0', "fail in copy_expand_pid");
3581           if (p == src_end && b == buf_end + 1) {
3582             // reach the end of the buffer.
3583             return true;
3584           }
3585         }
3586         p++;
3587         break;
3588       }
3589       default :
3590         *b++ = '%';
3591       }
3592     } else {
3593       *b++ = *p++;
3594     }
3595   }
3596   *b = '\0';
3597   return (p == src_end); // return false if not all of the source was copied
3598 }