1 /*
   2  * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/javaAssertions.hpp"
  27 #include "compiler/compilerOracle.hpp"
  28 #include "memory/allocation.inline.hpp"
  29 #include "memory/cardTableRS.hpp"
  30 #include "memory/referenceProcessor.hpp"
  31 #include "memory/universe.inline.hpp"
  32 #include "oops/oop.inline.hpp"
  33 #include "prims/jvmtiExport.hpp"
  34 #include "runtime/arguments.hpp"
  35 #include "runtime/globals_extension.hpp"
  36 #include "runtime/java.hpp"
  37 #include "services/management.hpp"
  38 #include "utilities/defaultStream.hpp"
  39 #include "utilities/taskqueue.hpp"
  40 #ifdef TARGET_ARCH_x86
  41 # include "vm_version_x86.hpp"
  42 #endif
  43 #ifdef TARGET_ARCH_sparc
  44 # include "vm_version_sparc.hpp"
  45 #endif
  46 #ifdef TARGET_ARCH_zero
  47 # include "vm_version_zero.hpp"
  48 #endif
  49 #ifdef TARGET_OS_FAMILY_linux
  50 # include "os_linux.inline.hpp"
  51 #endif
  52 #ifdef TARGET_OS_FAMILY_solaris
  53 # include "os_solaris.inline.hpp"
  54 #endif
  55 #ifdef TARGET_OS_FAMILY_windows
  56 # include "os_windows.inline.hpp"
  57 #endif
  58 #ifndef SERIALGC
  59 #include "gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.hpp"
  60 #endif
  61 
  62 #define DEFAULT_VENDOR_URL_BUG "http://java.sun.com/webapps/bugreport/crash.jsp"
  63 #define DEFAULT_JAVA_LAUNCHER  "generic"
  64 
  65 char**  Arguments::_jvm_flags_array             = NULL;
  66 int     Arguments::_num_jvm_flags               = 0;
  67 char**  Arguments::_jvm_args_array              = NULL;
  68 int     Arguments::_num_jvm_args                = 0;
  69 char*  Arguments::_java_command                 = NULL;
  70 SystemProperty* Arguments::_system_properties   = NULL;
  71 const char*  Arguments::_gc_log_filename        = NULL;
  72 bool   Arguments::_has_profile                  = false;
  73 bool   Arguments::_has_alloc_profile            = false;
  74 uintx  Arguments::_min_heap_size                = 0;
  75 Arguments::Mode Arguments::_mode                = _mixed;
  76 bool   Arguments::_java_compiler                = false;
  77 bool   Arguments::_xdebug_mode                  = false;
  78 const char*  Arguments::_java_vendor_url_bug    = DEFAULT_VENDOR_URL_BUG;
  79 const char*  Arguments::_sun_java_launcher      = DEFAULT_JAVA_LAUNCHER;
  80 int    Arguments::_sun_java_launcher_pid        = -1;
  81 
  82 // These parameters are reset in method parse_vm_init_args(JavaVMInitArgs*)
  83 bool   Arguments::_AlwaysCompileLoopMethods     = AlwaysCompileLoopMethods;
  84 bool   Arguments::_UseOnStackReplacement        = UseOnStackReplacement;
  85 bool   Arguments::_BackgroundCompilation        = BackgroundCompilation;
  86 bool   Arguments::_ClipInlining                 = ClipInlining;
  87 
  88 char*  Arguments::SharedArchivePath             = NULL;
  89 
  90 AgentLibraryList Arguments::_libraryList;
  91 AgentLibraryList Arguments::_agentList;
  92 
  93 abort_hook_t     Arguments::_abort_hook         = NULL;
  94 exit_hook_t      Arguments::_exit_hook          = NULL;
  95 vfprintf_hook_t  Arguments::_vfprintf_hook      = NULL;
  96 
  97 
  98 SystemProperty *Arguments::_java_ext_dirs = NULL;
  99 SystemProperty *Arguments::_java_endorsed_dirs = NULL;
 100 SystemProperty *Arguments::_sun_boot_library_path = NULL;
 101 SystemProperty *Arguments::_java_library_path = NULL;
 102 SystemProperty *Arguments::_java_home = NULL;
 103 SystemProperty *Arguments::_java_class_path = NULL;
 104 SystemProperty *Arguments::_sun_boot_class_path = NULL;
 105 
 106 char* Arguments::_meta_index_path = NULL;
 107 char* Arguments::_meta_index_dir = NULL;
 108 
 109 static bool force_client_mode = false;
 110 
 111 // Check if head of 'option' matches 'name', and sets 'tail' remaining part of option string
 112 
 113 static bool match_option(const JavaVMOption *option, const char* name,
 114                          const char** tail) {
 115   int len = (int)strlen(name);
 116   if (strncmp(option->optionString, name, len) == 0) {
 117     *tail = option->optionString + len;
 118     return true;
 119   } else {
 120     return false;
 121   }
 122 }
 123 
 124 static void logOption(const char* opt) {
 125   if (PrintVMOptions) {
 126     jio_fprintf(defaultStream::output_stream(), "VM option '%s'\n", opt);
 127   }
 128 }
 129 
 130 // Process java launcher properties.
 131 void Arguments::process_sun_java_launcher_properties(JavaVMInitArgs* args) {
 132   // See if sun.java.launcher or sun.java.launcher.pid is defined.
 133   // Must do this before setting up other system properties,
 134   // as some of them may depend on launcher type.
 135   for (int index = 0; index < args->nOptions; index++) {
 136     const JavaVMOption* option = args->options + index;
 137     const char* tail;
 138 
 139     if (match_option(option, "-Dsun.java.launcher=", &tail)) {
 140       process_java_launcher_argument(tail, option->extraInfo);
 141       continue;
 142     }
 143     if (match_option(option, "-Dsun.java.launcher.pid=", &tail)) {
 144       _sun_java_launcher_pid = atoi(tail);
 145       continue;
 146     }
 147   }
 148 }
 149 
 150 // Initialize system properties key and value.
 151 void Arguments::init_system_properties() {
 152 
 153   PropertyList_add(&_system_properties, new SystemProperty("java.vm.specification.name",
 154                                                                  "Java Virtual Machine Specification",  false));
 155   PropertyList_add(&_system_properties, new SystemProperty("java.vm.version", VM_Version::vm_release(),  false));
 156   PropertyList_add(&_system_properties, new SystemProperty("java.vm.name", VM_Version::vm_name(),  false));
 157   PropertyList_add(&_system_properties, new SystemProperty("java.vm.info", VM_Version::vm_info_string(),  true));
 158 
 159   // following are JVMTI agent writeable properties.
 160   // Properties values are set to NULL and they are
 161   // os specific they are initialized in os::init_system_properties_values().
 162   _java_ext_dirs = new SystemProperty("java.ext.dirs", NULL,  true);
 163   _java_endorsed_dirs = new SystemProperty("java.endorsed.dirs", NULL,  true);
 164   _sun_boot_library_path = new SystemProperty("sun.boot.library.path", NULL,  true);
 165   _java_library_path = new SystemProperty("java.library.path", NULL,  true);
 166   _java_home =  new SystemProperty("java.home", NULL,  true);
 167   _sun_boot_class_path = new SystemProperty("sun.boot.class.path", NULL,  true);
 168 
 169   _java_class_path = new SystemProperty("java.class.path", "",  true);
 170 
 171   // Add to System Property list.
 172   PropertyList_add(&_system_properties, _java_ext_dirs);
 173   PropertyList_add(&_system_properties, _java_endorsed_dirs);
 174   PropertyList_add(&_system_properties, _sun_boot_library_path);
 175   PropertyList_add(&_system_properties, _java_library_path);
 176   PropertyList_add(&_system_properties, _java_home);
 177   PropertyList_add(&_system_properties, _java_class_path);
 178   PropertyList_add(&_system_properties, _sun_boot_class_path);
 179 
 180   // Set OS specific system properties values
 181   os::init_system_properties_values();
 182 }
 183 
 184 
 185   // Update/Initialize System properties after JDK version number is known
 186 void Arguments::init_version_specific_system_properties() {
 187   enum { bufsz = 16 };
 188   char buffer[bufsz];
 189   const char* spec_vendor = "Sun Microsystems Inc.";
 190   uint32_t spec_version = 0;
 191 
 192   if (JDK_Version::is_gte_jdk17x_version()) {
 193     spec_vendor = "Oracle Corporation";
 194     spec_version = JDK_Version::current().major_version();
 195   }
 196   jio_snprintf(buffer, bufsz, "1." UINT32_FORMAT, spec_version);
 197 
 198   PropertyList_add(&_system_properties,
 199       new SystemProperty("java.vm.specification.vendor",  spec_vendor, false));
 200   PropertyList_add(&_system_properties,
 201       new SystemProperty("java.vm.specification.version", buffer, false));
 202   PropertyList_add(&_system_properties,
 203       new SystemProperty("java.vm.vendor", VM_Version::vm_vendor(),  false));
 204 }
 205 
 206 /**
 207  * Provide a slightly more user-friendly way of eliminating -XX flags.
 208  * When a flag is eliminated, it can be added to this list in order to
 209  * continue accepting this flag on the command-line, while issuing a warning
 210  * and ignoring the value.  Once the JDK version reaches the 'accept_until'
 211  * limit, we flatly refuse to admit the existence of the flag.  This allows
 212  * a flag to die correctly over JDK releases using HSX.
 213  */
 214 typedef struct {
 215   const char* name;
 216   JDK_Version obsoleted_in; // when the flag went away
 217   JDK_Version accept_until; // which version to start denying the existence
 218 } ObsoleteFlag;
 219 
 220 static ObsoleteFlag obsolete_jvm_flags[] = {
 221   { "UseTrainGC",                    JDK_Version::jdk(5), JDK_Version::jdk(7) },
 222   { "UseSpecialLargeObjectHandling", JDK_Version::jdk(5), JDK_Version::jdk(7) },
 223   { "UseOversizedCarHandling",       JDK_Version::jdk(5), JDK_Version::jdk(7) },
 224   { "TraceCarAllocation",            JDK_Version::jdk(5), JDK_Version::jdk(7) },
 225   { "PrintTrainGCProcessingStats",   JDK_Version::jdk(5), JDK_Version::jdk(7) },
 226   { "LogOfCarSpaceSize",             JDK_Version::jdk(5), JDK_Version::jdk(7) },
 227   { "OversizedCarThreshold",         JDK_Version::jdk(5), JDK_Version::jdk(7) },
 228   { "MinTickInterval",               JDK_Version::jdk(5), JDK_Version::jdk(7) },
 229   { "DefaultTickInterval",           JDK_Version::jdk(5), JDK_Version::jdk(7) },
 230   { "MaxTickInterval",               JDK_Version::jdk(5), JDK_Version::jdk(7) },
 231   { "DelayTickAdjustment",           JDK_Version::jdk(5), JDK_Version::jdk(7) },
 232   { "ProcessingToTenuringRatio",     JDK_Version::jdk(5), JDK_Version::jdk(7) },
 233   { "MinTrainLength",                JDK_Version::jdk(5), JDK_Version::jdk(7) },
 234   { "AppendRatio",         JDK_Version::jdk_update(6,10), JDK_Version::jdk(7) },
 235   { "DefaultMaxRAM",       JDK_Version::jdk_update(6,18), JDK_Version::jdk(7) },
 236   { "DefaultInitialRAMFraction",
 237                            JDK_Version::jdk_update(6,18), JDK_Version::jdk(7) },
 238   { "UseDepthFirstScavengeOrder",
 239                            JDK_Version::jdk_update(6,22), JDK_Version::jdk(7) },
 240   { "HandlePromotionFailure",
 241                            JDK_Version::jdk_update(6,24), JDK_Version::jdk(8) },
 242   { "MaxLiveObjectEvacuationRatio",
 243                            JDK_Version::jdk_update(6,24), JDK_Version::jdk(8) },
 244   { NULL, JDK_Version(0), JDK_Version(0) }
 245 };
 246 
 247 // Returns true if the flag is obsolete and fits into the range specified
 248 // for being ignored.  In the case that the flag is ignored, the 'version'
 249 // value is filled in with the version number when the flag became
 250 // obsolete so that that value can be displayed to the user.
 251 bool Arguments::is_newly_obsolete(const char *s, JDK_Version* version) {
 252   int i = 0;
 253   assert(version != NULL, "Must provide a version buffer");
 254   while (obsolete_jvm_flags[i].name != NULL) {
 255     const ObsoleteFlag& flag_status = obsolete_jvm_flags[i];
 256     // <flag>=xxx form
 257     // [-|+]<flag> form
 258     if ((strncmp(flag_status.name, s, strlen(flag_status.name)) == 0) ||
 259         ((s[0] == '+' || s[0] == '-') &&
 260         (strncmp(flag_status.name, &s[1], strlen(flag_status.name)) == 0))) {
 261       if (JDK_Version::current().compare(flag_status.accept_until) == -1) {
 262           *version = flag_status.obsoleted_in;
 263           return true;
 264       }
 265     }
 266     i++;
 267   }
 268   return false;
 269 }
 270 
 271 // Constructs the system class path (aka boot class path) from the following
 272 // components, in order:
 273 //
 274 //     prefix           // from -Xbootclasspath/p:...
 275 //     endorsed         // the expansion of -Djava.endorsed.dirs=...
 276 //     base             // from os::get_system_properties() or -Xbootclasspath=
 277 //     suffix           // from -Xbootclasspath/a:...
 278 //
 279 // java.endorsed.dirs is a list of directories; any jar or zip files in the
 280 // directories are added to the sysclasspath just before the base.
 281 //
 282 // This could be AllStatic, but it isn't needed after argument processing is
 283 // complete.
 284 class SysClassPath: public StackObj {
 285 public:
 286   SysClassPath(const char* base);
 287   ~SysClassPath();
 288 
 289   inline void set_base(const char* base);
 290   inline void add_prefix(const char* prefix);
 291   inline void add_suffix_to_prefix(const char* suffix);
 292   inline void add_suffix(const char* suffix);
 293   inline void reset_path(const char* base);
 294 
 295   // Expand the jar/zip files in each directory listed by the java.endorsed.dirs
 296   // property.  Must be called after all command-line arguments have been
 297   // processed (in particular, -Djava.endorsed.dirs=...) and before calling
 298   // combined_path().
 299   void expand_endorsed();
 300 
 301   inline const char* get_base()     const { return _items[_scp_base]; }
 302   inline const char* get_prefix()   const { return _items[_scp_prefix]; }
 303   inline const char* get_suffix()   const { return _items[_scp_suffix]; }
 304   inline const char* get_endorsed() const { return _items[_scp_endorsed]; }
 305 
 306   // Combine all the components into a single c-heap-allocated string; caller
 307   // must free the string if/when no longer needed.
 308   char* combined_path();
 309 
 310 private:
 311   // Utility routines.
 312   static char* add_to_path(const char* path, const char* str, bool prepend);
 313   static char* add_jars_to_path(char* path, const char* directory);
 314 
 315   inline void reset_item_at(int index);
 316 
 317   // Array indices for the items that make up the sysclasspath.  All except the
 318   // base are allocated in the C heap and freed by this class.
 319   enum {
 320     _scp_prefix,        // from -Xbootclasspath/p:...
 321     _scp_endorsed,      // the expansion of -Djava.endorsed.dirs=...
 322     _scp_base,          // the default sysclasspath
 323     _scp_suffix,        // from -Xbootclasspath/a:...
 324     _scp_nitems         // the number of items, must be last.
 325   };
 326 
 327   const char* _items[_scp_nitems];
 328   DEBUG_ONLY(bool _expansion_done;)
 329 };
 330 
 331 SysClassPath::SysClassPath(const char* base) {
 332   memset(_items, 0, sizeof(_items));
 333   _items[_scp_base] = base;
 334   DEBUG_ONLY(_expansion_done = false;)
 335 }
 336 
 337 SysClassPath::~SysClassPath() {
 338   // Free everything except the base.
 339   for (int i = 0; i < _scp_nitems; ++i) {
 340     if (i != _scp_base) reset_item_at(i);
 341   }
 342   DEBUG_ONLY(_expansion_done = false;)
 343 }
 344 
 345 inline void SysClassPath::set_base(const char* base) {
 346   _items[_scp_base] = base;
 347 }
 348 
 349 inline void SysClassPath::add_prefix(const char* prefix) {
 350   _items[_scp_prefix] = add_to_path(_items[_scp_prefix], prefix, true);
 351 }
 352 
 353 inline void SysClassPath::add_suffix_to_prefix(const char* suffix) {
 354   _items[_scp_prefix] = add_to_path(_items[_scp_prefix], suffix, false);
 355 }
 356 
 357 inline void SysClassPath::add_suffix(const char* suffix) {
 358   _items[_scp_suffix] = add_to_path(_items[_scp_suffix], suffix, false);
 359 }
 360 
 361 inline void SysClassPath::reset_item_at(int index) {
 362   assert(index < _scp_nitems && index != _scp_base, "just checking");
 363   if (_items[index] != NULL) {
 364     FREE_C_HEAP_ARRAY(char, _items[index]);
 365     _items[index] = NULL;
 366   }
 367 }
 368 
 369 inline void SysClassPath::reset_path(const char* base) {
 370   // Clear the prefix and suffix.
 371   reset_item_at(_scp_prefix);
 372   reset_item_at(_scp_suffix);
 373   set_base(base);
 374 }
 375 
 376 //------------------------------------------------------------------------------
 377 
 378 void SysClassPath::expand_endorsed() {
 379   assert(_items[_scp_endorsed] == NULL, "can only be called once.");
 380 
 381   const char* path = Arguments::get_property("java.endorsed.dirs");
 382   if (path == NULL) {
 383     path = Arguments::get_endorsed_dir();
 384     assert(path != NULL, "no default for java.endorsed.dirs");
 385   }
 386 
 387   char* expanded_path = NULL;
 388   const char separator = *os::path_separator();
 389   const char* const end = path + strlen(path);
 390   while (path < end) {
 391     const char* tmp_end = strchr(path, separator);
 392     if (tmp_end == NULL) {
 393       expanded_path = add_jars_to_path(expanded_path, path);
 394       path = end;
 395     } else {
 396       char* dirpath = NEW_C_HEAP_ARRAY(char, tmp_end - path + 1);
 397       memcpy(dirpath, path, tmp_end - path);
 398       dirpath[tmp_end - path] = '\0';
 399       expanded_path = add_jars_to_path(expanded_path, dirpath);
 400       FREE_C_HEAP_ARRAY(char, dirpath);
 401       path = tmp_end + 1;
 402     }
 403   }
 404   _items[_scp_endorsed] = expanded_path;
 405   DEBUG_ONLY(_expansion_done = true;)
 406 }
 407 
 408 // Combine the bootclasspath elements, some of which may be null, into a single
 409 // c-heap-allocated string.
 410 char* SysClassPath::combined_path() {
 411   assert(_items[_scp_base] != NULL, "empty default sysclasspath");
 412   assert(_expansion_done, "must call expand_endorsed() first.");
 413 
 414   size_t lengths[_scp_nitems];
 415   size_t total_len = 0;
 416 
 417   const char separator = *os::path_separator();
 418 
 419   // Get the lengths.
 420   int i;
 421   for (i = 0; i < _scp_nitems; ++i) {
 422     if (_items[i] != NULL) {
 423       lengths[i] = strlen(_items[i]);
 424       // Include space for the separator char (or a NULL for the last item).
 425       total_len += lengths[i] + 1;
 426     }
 427   }
 428   assert(total_len > 0, "empty sysclasspath not allowed");
 429 
 430   // Copy the _items to a single string.
 431   char* cp = NEW_C_HEAP_ARRAY(char, total_len);
 432   char* cp_tmp = cp;
 433   for (i = 0; i < _scp_nitems; ++i) {
 434     if (_items[i] != NULL) {
 435       memcpy(cp_tmp, _items[i], lengths[i]);
 436       cp_tmp += lengths[i];
 437       *cp_tmp++ = separator;
 438     }
 439   }
 440   *--cp_tmp = '\0';     // Replace the extra separator.
 441   return cp;
 442 }
 443 
 444 // Note:  path must be c-heap-allocated (or NULL); it is freed if non-null.
 445 char*
 446 SysClassPath::add_to_path(const char* path, const char* str, bool prepend) {
 447   char *cp;
 448 
 449   assert(str != NULL, "just checking");
 450   if (path == NULL) {
 451     size_t len = strlen(str) + 1;
 452     cp = NEW_C_HEAP_ARRAY(char, len);
 453     memcpy(cp, str, len);                       // copy the trailing null
 454   } else {
 455     const char separator = *os::path_separator();
 456     size_t old_len = strlen(path);
 457     size_t str_len = strlen(str);
 458     size_t len = old_len + str_len + 2;
 459 
 460     if (prepend) {
 461       cp = NEW_C_HEAP_ARRAY(char, len);
 462       char* cp_tmp = cp;
 463       memcpy(cp_tmp, str, str_len);
 464       cp_tmp += str_len;
 465       *cp_tmp = separator;
 466       memcpy(++cp_tmp, path, old_len + 1);      // copy the trailing null
 467       FREE_C_HEAP_ARRAY(char, path);
 468     } else {
 469       cp = REALLOC_C_HEAP_ARRAY(char, path, len);
 470       char* cp_tmp = cp + old_len;
 471       *cp_tmp = separator;
 472       memcpy(++cp_tmp, str, str_len + 1);       // copy the trailing null
 473     }
 474   }
 475   return cp;
 476 }
 477 
 478 // Scan the directory and append any jar or zip files found to path.
 479 // Note:  path must be c-heap-allocated (or NULL); it is freed if non-null.
 480 char* SysClassPath::add_jars_to_path(char* path, const char* directory) {
 481   DIR* dir = os::opendir(directory);
 482   if (dir == NULL) return path;
 483 
 484   char dir_sep[2] = { '\0', '\0' };
 485   size_t directory_len = strlen(directory);
 486   const char fileSep = *os::file_separator();
 487   if (directory[directory_len - 1] != fileSep) dir_sep[0] = fileSep;
 488 
 489   /* Scan the directory for jars/zips, appending them to path. */
 490   struct dirent *entry;
 491   char *dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory));
 492   while ((entry = os::readdir(dir, (dirent *) dbuf)) != NULL) {
 493     const char* name = entry->d_name;
 494     const char* ext = name + strlen(name) - 4;
 495     bool isJarOrZip = ext > name &&
 496       (os::file_name_strcmp(ext, ".jar") == 0 ||
 497        os::file_name_strcmp(ext, ".zip") == 0);
 498     if (isJarOrZip) {
 499       char* jarpath = NEW_C_HEAP_ARRAY(char, directory_len + 2 + strlen(name));
 500       sprintf(jarpath, "%s%s%s", directory, dir_sep, name);
 501       path = add_to_path(path, jarpath, false);
 502       FREE_C_HEAP_ARRAY(char, jarpath);
 503     }
 504   }
 505   FREE_C_HEAP_ARRAY(char, dbuf);
 506   os::closedir(dir);
 507   return path;
 508 }
 509 
 510 // Parses a memory size specification string.
 511 static bool atomull(const char *s, julong* result) {
 512   julong n = 0;
 513   int args_read = sscanf(s, os::julong_format_specifier(), &n);
 514   if (args_read != 1) {
 515     return false;
 516   }
 517   while (*s != '\0' && isdigit(*s)) {
 518     s++;
 519   }
 520   // 4705540: illegal if more characters are found after the first non-digit
 521   if (strlen(s) > 1) {
 522     return false;
 523   }
 524   switch (*s) {
 525     case 'T': case 't':
 526       *result = n * G * K;
 527       // Check for overflow.
 528       if (*result/((julong)G * K) != n) return false;
 529       return true;
 530     case 'G': case 'g':
 531       *result = n * G;
 532       if (*result/G != n) return false;
 533       return true;
 534     case 'M': case 'm':
 535       *result = n * M;
 536       if (*result/M != n) return false;
 537       return true;
 538     case 'K': case 'k':
 539       *result = n * K;
 540       if (*result/K != n) return false;
 541       return true;
 542     case '\0':
 543       *result = n;
 544       return true;
 545     default:
 546       return false;
 547   }
 548 }
 549 
 550 Arguments::ArgsRange Arguments::check_memory_size(julong size, julong min_size) {
 551   if (size < min_size) return arg_too_small;
 552   // Check that size will fit in a size_t (only relevant on 32-bit)
 553   if (size > max_uintx) return arg_too_big;
 554   return arg_in_range;
 555 }
 556 
 557 // Describe an argument out of range error
 558 void Arguments::describe_range_error(ArgsRange errcode) {
 559   switch(errcode) {
 560   case arg_too_big:
 561     jio_fprintf(defaultStream::error_stream(),
 562                 "The specified size exceeds the maximum "
 563                 "representable size.\n");
 564     break;
 565   case arg_too_small:
 566   case arg_unreadable:
 567   case arg_in_range:
 568     // do nothing for now
 569     break;
 570   default:
 571     ShouldNotReachHere();
 572   }
 573 }
 574 
 575 static bool set_bool_flag(char* name, bool value, FlagValueOrigin origin) {
 576   return CommandLineFlags::boolAtPut(name, &value, origin);
 577 }
 578 
 579 static bool set_fp_numeric_flag(char* name, char* value, FlagValueOrigin origin) {
 580   double v;
 581   if (sscanf(value, "%lf", &v) != 1) {
 582     return false;
 583   }
 584 
 585   if (CommandLineFlags::doubleAtPut(name, &v, origin)) {
 586     return true;
 587   }
 588   return false;
 589 }
 590 
 591 static bool set_numeric_flag(char* name, char* value, FlagValueOrigin origin) {
 592   julong v;
 593   intx intx_v;
 594   bool is_neg = false;
 595   // Check the sign first since atomull() parses only unsigned values.
 596   if (*value == '-') {
 597     if (!CommandLineFlags::intxAt(name, &intx_v)) {
 598       return false;
 599     }
 600     value++;
 601     is_neg = true;
 602   }
 603   if (!atomull(value, &v)) {
 604     return false;
 605   }
 606   intx_v = (intx) v;
 607   if (is_neg) {
 608     intx_v = -intx_v;
 609   }
 610   if (CommandLineFlags::intxAtPut(name, &intx_v, origin)) {
 611     return true;
 612   }
 613   uintx uintx_v = (uintx) v;
 614   if (!is_neg && CommandLineFlags::uintxAtPut(name, &uintx_v, origin)) {
 615     return true;
 616   }
 617   uint64_t uint64_t_v = (uint64_t) v;
 618   if (!is_neg && CommandLineFlags::uint64_tAtPut(name, &uint64_t_v, origin)) {
 619     return true;
 620   }
 621   return false;
 622 }
 623 
 624 static bool set_string_flag(char* name, const char* value, FlagValueOrigin origin) {
 625   if (!CommandLineFlags::ccstrAtPut(name, &value, origin))  return false;
 626   // Contract:  CommandLineFlags always returns a pointer that needs freeing.
 627   FREE_C_HEAP_ARRAY(char, value);
 628   return true;
 629 }
 630 
 631 static bool append_to_string_flag(char* name, const char* new_value, FlagValueOrigin origin) {
 632   const char* old_value = "";
 633   if (!CommandLineFlags::ccstrAt(name, &old_value))  return false;
 634   size_t old_len = old_value != NULL ? strlen(old_value) : 0;
 635   size_t new_len = strlen(new_value);
 636   const char* value;
 637   char* free_this_too = NULL;
 638   if (old_len == 0) {
 639     value = new_value;
 640   } else if (new_len == 0) {
 641     value = old_value;
 642   } else {
 643     char* buf = NEW_C_HEAP_ARRAY(char, old_len + 1 + new_len + 1);
 644     // each new setting adds another LINE to the switch:
 645     sprintf(buf, "%s\n%s", old_value, new_value);
 646     value = buf;
 647     free_this_too = buf;
 648   }
 649   (void) CommandLineFlags::ccstrAtPut(name, &value, origin);
 650   // CommandLineFlags always returns a pointer that needs freeing.
 651   FREE_C_HEAP_ARRAY(char, value);
 652   if (free_this_too != NULL) {
 653     // CommandLineFlags made its own copy, so I must delete my own temp. buffer.
 654     FREE_C_HEAP_ARRAY(char, free_this_too);
 655   }
 656   return true;
 657 }
 658 
 659 bool Arguments::parse_argument(const char* arg, FlagValueOrigin origin) {
 660 
 661   // range of acceptable characters spelled out for portability reasons
 662 #define NAME_RANGE  "[abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_]"
 663 #define BUFLEN 255
 664   char name[BUFLEN+1];
 665   char dummy;
 666 
 667   if (sscanf(arg, "-%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
 668     return set_bool_flag(name, false, origin);
 669   }
 670   if (sscanf(arg, "+%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
 671     return set_bool_flag(name, true, origin);
 672   }
 673 
 674   char punct;
 675   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "%c", name, &punct) == 2 && punct == '=') {
 676     const char* value = strchr(arg, '=') + 1;
 677     Flag* flag = Flag::find_flag(name, strlen(name));
 678     if (flag != NULL && flag->is_ccstr()) {
 679       if (flag->ccstr_accumulates()) {
 680         return append_to_string_flag(name, value, origin);
 681       } else {
 682         if (value[0] == '\0') {
 683           value = NULL;
 684         }
 685         return set_string_flag(name, value, origin);
 686       }
 687     }
 688   }
 689 
 690   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE ":%c", name, &punct) == 2 && punct == '=') {
 691     const char* value = strchr(arg, '=') + 1;
 692     // -XX:Foo:=xxx will reset the string flag to the given value.
 693     if (value[0] == '\0') {
 694       value = NULL;
 695     }
 696     return set_string_flag(name, value, origin);
 697   }
 698 
 699 #define SIGNED_FP_NUMBER_RANGE "[-0123456789.]"
 700 #define SIGNED_NUMBER_RANGE    "[-0123456789]"
 701 #define        NUMBER_RANGE    "[0123456789]"
 702   char value[BUFLEN + 1];
 703   char value2[BUFLEN + 1];
 704   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_NUMBER_RANGE "." "%" XSTR(BUFLEN) NUMBER_RANGE "%c", name, value, value2, &dummy) == 3) {
 705     // Looks like a floating-point number -- try again with more lenient format string
 706     if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_FP_NUMBER_RANGE "%c", name, value, &dummy) == 2) {
 707       return set_fp_numeric_flag(name, value, origin);
 708     }
 709   }
 710 
 711 #define VALUE_RANGE "[-kmgtKMGT0123456789]"
 712   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) VALUE_RANGE "%c", name, value, &dummy) == 2) {
 713     return set_numeric_flag(name, value, origin);
 714   }
 715 
 716   return false;
 717 }
 718 
 719 void Arguments::add_string(char*** bldarray, int* count, const char* arg) {
 720   assert(bldarray != NULL, "illegal argument");
 721 
 722   if (arg == NULL) {
 723     return;
 724   }
 725 
 726   int index = *count;
 727 
 728   // expand the array and add arg to the last element
 729   (*count)++;
 730   if (*bldarray == NULL) {
 731     *bldarray = NEW_C_HEAP_ARRAY(char*, *count);
 732   } else {
 733     *bldarray = REALLOC_C_HEAP_ARRAY(char*, *bldarray, *count);
 734   }
 735   (*bldarray)[index] = strdup(arg);
 736 }
 737 
 738 void Arguments::build_jvm_args(const char* arg) {
 739   add_string(&_jvm_args_array, &_num_jvm_args, arg);
 740 }
 741 
 742 void Arguments::build_jvm_flags(const char* arg) {
 743   add_string(&_jvm_flags_array, &_num_jvm_flags, arg);
 744 }
 745 
 746 // utility function to return a string that concatenates all
 747 // strings in a given char** array
 748 const char* Arguments::build_resource_string(char** args, int count) {
 749   if (args == NULL || count == 0) {
 750     return NULL;
 751   }
 752   size_t length = strlen(args[0]) + 1; // add 1 for the null terminator
 753   for (int i = 1; i < count; i++) {
 754     length += strlen(args[i]) + 1; // add 1 for a space
 755   }
 756   char* s = NEW_RESOURCE_ARRAY(char, length);
 757   strcpy(s, args[0]);
 758   for (int j = 1; j < count; j++) {
 759     strcat(s, " ");
 760     strcat(s, args[j]);
 761   }
 762   return (const char*) s;
 763 }
 764 
 765 void Arguments::print_on(outputStream* st) {
 766   st->print_cr("VM Arguments:");
 767   if (num_jvm_flags() > 0) {
 768     st->print("jvm_flags: "); print_jvm_flags_on(st);
 769   }
 770   if (num_jvm_args() > 0) {
 771     st->print("jvm_args: "); print_jvm_args_on(st);
 772   }
 773   st->print_cr("java_command: %s", java_command() ? java_command() : "<unknown>");
 774   st->print_cr("Launcher Type: %s", _sun_java_launcher);
 775 }
 776 
 777 void Arguments::print_jvm_flags_on(outputStream* st) {
 778   if (_num_jvm_flags > 0) {
 779     for (int i=0; i < _num_jvm_flags; i++) {
 780       st->print("%s ", _jvm_flags_array[i]);
 781     }
 782     st->print_cr("");
 783   }
 784 }
 785 
 786 void Arguments::print_jvm_args_on(outputStream* st) {
 787   if (_num_jvm_args > 0) {
 788     for (int i=0; i < _num_jvm_args; i++) {
 789       st->print("%s ", _jvm_args_array[i]);
 790     }
 791     st->print_cr("");
 792   }
 793 }
 794 
 795 bool Arguments::process_argument(const char* arg,
 796     jboolean ignore_unrecognized, FlagValueOrigin origin) {
 797 
 798   JDK_Version since = JDK_Version();
 799 
 800   if (parse_argument(arg, origin)) {
 801     // do nothing
 802   } else if (is_newly_obsolete(arg, &since)) {
 803     enum { bufsize = 256 };
 804     char buffer[bufsize];
 805     since.to_string(buffer, bufsize);
 806     jio_fprintf(defaultStream::error_stream(),
 807       "Warning: The flag %s has been EOL'd as of %s and will"
 808       " be ignored\n", arg, buffer);
 809   } else {
 810     if (!ignore_unrecognized) {
 811       jio_fprintf(defaultStream::error_stream(),
 812                   "Unrecognized VM option '%s'\n", arg);
 813       // allow for commandline "commenting out" options like -XX:#+Verbose
 814       if (strlen(arg) == 0 || arg[0] != '#') {
 815         return false;
 816       }
 817     }
 818   }
 819   return true;
 820 }
 821 
 822 bool Arguments::process_settings_file(const char* file_name, bool should_exist, jboolean ignore_unrecognized) {
 823   FILE* stream = fopen(file_name, "rb");
 824   if (stream == NULL) {
 825     if (should_exist) {
 826       jio_fprintf(defaultStream::error_stream(),
 827                   "Could not open settings file %s\n", file_name);
 828       return false;
 829     } else {
 830       return true;
 831     }
 832   }
 833 
 834   char token[1024];
 835   int  pos = 0;
 836 
 837   bool in_white_space = true;
 838   bool in_comment     = false;
 839   bool in_quote       = false;
 840   char quote_c        = 0;
 841   bool result         = true;
 842 
 843   int c = getc(stream);
 844   while(c != EOF) {
 845     if (in_white_space) {
 846       if (in_comment) {
 847         if (c == '\n') in_comment = false;
 848       } else {
 849         if (c == '#') in_comment = true;
 850         else if (!isspace(c)) {
 851           in_white_space = false;
 852           token[pos++] = c;
 853         }
 854       }
 855     } else {
 856       if (c == '\n' || (!in_quote && isspace(c))) {
 857         // token ends at newline, or at unquoted whitespace
 858         // this allows a way to include spaces in string-valued options
 859         token[pos] = '\0';
 860         logOption(token);
 861         result &= process_argument(token, ignore_unrecognized, CONFIG_FILE);
 862         build_jvm_flags(token);
 863         pos = 0;
 864         in_white_space = true;
 865         in_quote = false;
 866       } else if (!in_quote && (c == '\'' || c == '"')) {
 867         in_quote = true;
 868         quote_c = c;
 869       } else if (in_quote && (c == quote_c)) {
 870         in_quote = false;
 871       } else {
 872         token[pos++] = c;
 873       }
 874     }
 875     c = getc(stream);
 876   }
 877   if (pos > 0) {
 878     token[pos] = '\0';
 879     result &= process_argument(token, ignore_unrecognized, CONFIG_FILE);
 880     build_jvm_flags(token);
 881   }
 882   fclose(stream);
 883   return result;
 884 }
 885 
 886 //=============================================================================================================
 887 // Parsing of properties (-D)
 888 
 889 const char* Arguments::get_property(const char* key) {
 890   return PropertyList_get_value(system_properties(), key);
 891 }
 892 
 893 bool Arguments::add_property(const char* prop) {
 894   const char* eq = strchr(prop, '=');
 895   char* key;
 896   // ns must be static--its address may be stored in a SystemProperty object.
 897   const static char ns[1] = {0};
 898   char* value = (char *)ns;
 899 
 900   size_t key_len = (eq == NULL) ? strlen(prop) : (eq - prop);
 901   key = AllocateHeap(key_len + 1, "add_property");
 902   strncpy(key, prop, key_len);
 903   key[key_len] = '\0';
 904 
 905   if (eq != NULL) {
 906     size_t value_len = strlen(prop) - key_len - 1;
 907     value = AllocateHeap(value_len + 1, "add_property");
 908     strncpy(value, &prop[key_len + 1], value_len + 1);
 909   }
 910 
 911   if (strcmp(key, "java.compiler") == 0) {
 912     process_java_compiler_argument(value);
 913     FreeHeap(key);
 914     if (eq != NULL) {
 915       FreeHeap(value);
 916     }
 917     return true;
 918   } else if (strcmp(key, "sun.java.command") == 0) {
 919     _java_command = value;
 920 
 921     // Record value in Arguments, but let it get passed to Java.
 922   } else if (strcmp(key, "sun.java.launcher.pid") == 0) {
 923     // launcher.pid property is private and is processed
 924     // in process_sun_java_launcher_properties();
 925     // the sun.java.launcher property is passed on to the java application
 926     FreeHeap(key);
 927     if (eq != NULL) {
 928       FreeHeap(value);
 929     }
 930     return true;
 931   } else if (strcmp(key, "java.vendor.url.bug") == 0) {
 932     // save it in _java_vendor_url_bug, so JVM fatal error handler can access
 933     // its value without going through the property list or making a Java call.
 934     _java_vendor_url_bug = value;
 935   } else if (strcmp(key, "sun.boot.library.path") == 0) {
 936     PropertyList_unique_add(&_system_properties, key, value, true);
 937     return true;
 938   }
 939   // Create new property and add at the end of the list
 940   PropertyList_unique_add(&_system_properties, key, value);
 941   return true;
 942 }
 943 
 944 //===========================================================================================================
 945 // Setting int/mixed/comp mode flags
 946 
 947 void Arguments::set_mode_flags(Mode mode) {
 948   // Set up default values for all flags.
 949   // If you add a flag to any of the branches below,
 950   // add a default value for it here.
 951   set_java_compiler(false);
 952   _mode                      = mode;
 953 
 954   // Ensure Agent_OnLoad has the correct initial values.
 955   // This may not be the final mode; mode may change later in onload phase.
 956   PropertyList_unique_add(&_system_properties, "java.vm.info",
 957                           (char*)Abstract_VM_Version::vm_info_string(), false);
 958 
 959   UseInterpreter             = true;
 960   UseCompiler                = true;
 961   UseLoopCounter             = true;
 962 
 963   // Default values may be platform/compiler dependent -
 964   // use the saved values
 965   ClipInlining               = Arguments::_ClipInlining;
 966   AlwaysCompileLoopMethods   = Arguments::_AlwaysCompileLoopMethods;
 967   UseOnStackReplacement      = Arguments::_UseOnStackReplacement;
 968   BackgroundCompilation      = Arguments::_BackgroundCompilation;
 969 
 970   // Change from defaults based on mode
 971   switch (mode) {
 972   default:
 973     ShouldNotReachHere();
 974     break;
 975   case _int:
 976     UseCompiler              = false;
 977     UseLoopCounter           = false;
 978     AlwaysCompileLoopMethods = false;
 979     UseOnStackReplacement    = false;
 980     break;
 981   case _mixed:
 982     // same as default
 983     break;
 984   case _comp:
 985     UseInterpreter           = false;
 986     BackgroundCompilation    = false;
 987     ClipInlining             = false;
 988     break;
 989   }
 990 }
 991 
 992 // Conflict: required to use shared spaces (-Xshare:on), but
 993 // incompatible command line options were chosen.
 994 
 995 static void no_shared_spaces() {
 996   if (RequireSharedSpaces) {
 997     jio_fprintf(defaultStream::error_stream(),
 998       "Class data sharing is inconsistent with other specified options.\n");
 999     vm_exit_during_initialization("Unable to use shared archive.", NULL);
1000   } else {
1001     FLAG_SET_DEFAULT(UseSharedSpaces, false);
1002   }
1003 }
1004 
1005 void Arguments::check_compressed_oops_compat() {
1006 #ifdef _LP64
1007   assert(UseCompressedOops, "Precondition");
1008   // Is it on by default or set on ergonomically
1009   bool is_on_by_default = FLAG_IS_DEFAULT(UseCompressedOops) || FLAG_IS_ERGO(UseCompressedOops);
1010 
1011   // If dumping an archive or forcing its use, disable compressed oops if possible
1012   if (DumpSharedSpaces || RequireSharedSpaces) {
1013     if (is_on_by_default) {
1014       FLAG_SET_DEFAULT(UseCompressedOops, false);
1015       return;
1016     } else {
1017       vm_exit_during_initialization(
1018         "Class Data Sharing is not supported with compressed oops yet", NULL);
1019     }
1020   } else if (UseSharedSpaces) {
1021     // UseSharedSpaces is on by default. With compressed oops, we turn it off.
1022     FLAG_SET_DEFAULT(UseSharedSpaces, false);
1023   }
1024 #endif
1025 }
1026 
1027 void Arguments::set_tiered_flags() {
1028   if (FLAG_IS_DEFAULT(CompilationPolicyChoice)) {
1029     FLAG_SET_DEFAULT(CompilationPolicyChoice, 2);
1030   }
1031   if (CompilationPolicyChoice < 2) {
1032     vm_exit_during_initialization(
1033       "Incompatible compilation policy selected", NULL);
1034   }
1035   // Increase the code cache size - tiered compiles a lot more.
1036   if (FLAG_IS_DEFAULT(ReservedCodeCacheSize)) {
1037     FLAG_SET_DEFAULT(ReservedCodeCacheSize, ReservedCodeCacheSize * 2);
1038   }
1039 }
1040 
1041 #ifndef KERNEL
1042 // If the user has chosen ParallelGCThreads > 0, we set UseParNewGC
1043 // if it's not explictly set or unset. If the user has chosen
1044 // UseParNewGC and not explicitly set ParallelGCThreads we
1045 // set it, unless this is a single cpu machine.
1046 void Arguments::set_parnew_gc_flags() {
1047   assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC && !UseG1GC,
1048          "control point invariant");
1049   assert(UseParNewGC, "Error");
1050 
1051   // Turn off AdaptiveSizePolicy by default for parnew until it is
1052   // complete.
1053   if (FLAG_IS_DEFAULT(UseAdaptiveSizePolicy)) {
1054     FLAG_SET_DEFAULT(UseAdaptiveSizePolicy, false);
1055   }
1056 
1057   if (ParallelGCThreads == 0) {
1058     FLAG_SET_DEFAULT(ParallelGCThreads,
1059                      Abstract_VM_Version::parallel_worker_threads());
1060     if (ParallelGCThreads == 1) {
1061       FLAG_SET_DEFAULT(UseParNewGC, false);
1062       FLAG_SET_DEFAULT(ParallelGCThreads, 0);
1063     }
1064   }
1065   if (UseParNewGC) {
1066     // CDS doesn't work with ParNew yet
1067     no_shared_spaces();
1068 
1069     // By default YoungPLABSize and OldPLABSize are set to 4096 and 1024 respectively,
1070     // these settings are default for Parallel Scavenger. For ParNew+Tenured configuration
1071     // we set them to 1024 and 1024.
1072     // See CR 6362902.
1073     if (FLAG_IS_DEFAULT(YoungPLABSize)) {
1074       FLAG_SET_DEFAULT(YoungPLABSize, (intx)1024);
1075     }
1076     if (FLAG_IS_DEFAULT(OldPLABSize)) {
1077       FLAG_SET_DEFAULT(OldPLABSize, (intx)1024);
1078     }
1079 
1080     // AlwaysTenure flag should make ParNew promote all at first collection.
1081     // See CR 6362902.
1082     if (AlwaysTenure) {
1083       FLAG_SET_CMDLINE(intx, MaxTenuringThreshold, 0);
1084     }
1085     // When using compressed oops, we use local overflow stacks,
1086     // rather than using a global overflow list chained through
1087     // the klass word of the object's pre-image.
1088     if (UseCompressedOops && !ParGCUseLocalOverflow) {
1089       if (!FLAG_IS_DEFAULT(ParGCUseLocalOverflow)) {
1090         warning("Forcing +ParGCUseLocalOverflow: needed if using compressed references");
1091       }
1092       FLAG_SET_DEFAULT(ParGCUseLocalOverflow, true);
1093     }
1094     assert(ParGCUseLocalOverflow || !UseCompressedOops, "Error");
1095   }
1096 }
1097 
1098 // Adjust some sizes to suit CMS and/or ParNew needs; these work well on
1099 // sparc/solaris for certain applications, but would gain from
1100 // further optimization and tuning efforts, and would almost
1101 // certainly gain from analysis of platform and environment.
1102 void Arguments::set_cms_and_parnew_gc_flags() {
1103   assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC, "Error");
1104   assert(UseConcMarkSweepGC, "CMS is expected to be on here");
1105 
1106   // If we are using CMS, we prefer to UseParNewGC,
1107   // unless explicitly forbidden.
1108   if (FLAG_IS_DEFAULT(UseParNewGC)) {
1109     FLAG_SET_ERGO(bool, UseParNewGC, true);
1110   }
1111 
1112   // Turn off AdaptiveSizePolicy by default for cms until it is
1113   // complete.
1114   if (FLAG_IS_DEFAULT(UseAdaptiveSizePolicy)) {
1115     FLAG_SET_DEFAULT(UseAdaptiveSizePolicy, false);
1116   }
1117 
1118   // In either case, adjust ParallelGCThreads and/or UseParNewGC
1119   // as needed.
1120   if (UseParNewGC) {
1121     set_parnew_gc_flags();
1122   }
1123 
1124   // Now make adjustments for CMS
1125   size_t young_gen_per_worker;
1126   intx new_ratio;
1127   size_t min_new_default;
1128   intx tenuring_default;
1129   if (CMSUseOldDefaults) {  // old defaults: "old" as of 6.0
1130     if FLAG_IS_DEFAULT(CMSYoungGenPerWorker) {
1131       FLAG_SET_ERGO(intx, CMSYoungGenPerWorker, 4*M);
1132     }
1133     young_gen_per_worker = 4*M;
1134     new_ratio = (intx)15;
1135     min_new_default = 4*M;
1136     tenuring_default = (intx)0;
1137   } else { // new defaults: "new" as of 6.0
1138     young_gen_per_worker = CMSYoungGenPerWorker;
1139     new_ratio = (intx)7;
1140     min_new_default = 16*M;
1141     tenuring_default = (intx)4;
1142   }
1143 
1144   // Preferred young gen size for "short" pauses
1145   const uintx parallel_gc_threads =
1146     (ParallelGCThreads == 0 ? 1 : ParallelGCThreads);
1147   const size_t preferred_max_new_size_unaligned =
1148     ScaleForWordSize(young_gen_per_worker * parallel_gc_threads);
1149   const size_t preferred_max_new_size =
1150     align_size_up(preferred_max_new_size_unaligned, os::vm_page_size());
1151 
1152   // Unless explicitly requested otherwise, size young gen
1153   // for "short" pauses ~ 4M*ParallelGCThreads
1154 
1155   // If either MaxNewSize or NewRatio is set on the command line,
1156   // assume the user is trying to set the size of the young gen.
1157 
1158   if (FLAG_IS_DEFAULT(MaxNewSize) && FLAG_IS_DEFAULT(NewRatio)) {
1159 
1160     // Set MaxNewSize to our calculated preferred_max_new_size unless
1161     // NewSize was set on the command line and it is larger than
1162     // preferred_max_new_size.
1163     if (!FLAG_IS_DEFAULT(NewSize)) {   // NewSize explicitly set at command-line
1164       FLAG_SET_ERGO(uintx, MaxNewSize, MAX2(NewSize, preferred_max_new_size));
1165     } else {
1166       FLAG_SET_ERGO(uintx, MaxNewSize, preferred_max_new_size);
1167     }
1168     if (PrintGCDetails && Verbose) {
1169       // Too early to use gclog_or_tty
1170       tty->print_cr("Ergo set MaxNewSize: " SIZE_FORMAT, MaxNewSize);
1171     }
1172 
1173     // Unless explicitly requested otherwise, prefer a large
1174     // Old to Young gen size so as to shift the collection load
1175     // to the old generation concurrent collector
1176 
1177     // If this is only guarded by FLAG_IS_DEFAULT(NewRatio)
1178     // then NewSize and OldSize may be calculated.  That would
1179     // generally lead to some differences with ParNewGC for which
1180     // there was no obvious reason.  Also limit to the case where
1181     // MaxNewSize has not been set.
1182 
1183     FLAG_SET_ERGO(intx, NewRatio, MAX2(NewRatio, new_ratio));
1184 
1185     // Code along this path potentially sets NewSize and OldSize
1186 
1187     // Calculate the desired minimum size of the young gen but if
1188     // NewSize has been set on the command line, use it here since
1189     // it should be the final value.
1190     size_t min_new;
1191     if (FLAG_IS_DEFAULT(NewSize)) {
1192       min_new = align_size_up(ScaleForWordSize(min_new_default),
1193                               os::vm_page_size());
1194     } else {
1195       min_new = NewSize;
1196     }
1197     size_t prev_initial_size = InitialHeapSize;
1198     if (prev_initial_size != 0 && prev_initial_size < min_new + OldSize) {
1199       FLAG_SET_ERGO(uintx, InitialHeapSize, min_new + OldSize);
1200       // Currently minimum size and the initial heap sizes are the same.
1201       set_min_heap_size(InitialHeapSize);
1202       if (PrintGCDetails && Verbose) {
1203         warning("Initial heap size increased to " SIZE_FORMAT " M from "
1204                 SIZE_FORMAT " M; use -XX:NewSize=... for finer control.",
1205                 InitialHeapSize/M, prev_initial_size/M);
1206       }
1207     }
1208 
1209     // MaxHeapSize is aligned down in collectorPolicy
1210     size_t max_heap =
1211       align_size_down(MaxHeapSize,
1212                       CardTableRS::ct_max_alignment_constraint());
1213 
1214     if (PrintGCDetails && Verbose) {
1215       // Too early to use gclog_or_tty
1216       tty->print_cr("CMS set min_heap_size: " SIZE_FORMAT
1217            " initial_heap_size:  " SIZE_FORMAT
1218            " max_heap: " SIZE_FORMAT,
1219            min_heap_size(), InitialHeapSize, max_heap);
1220     }
1221     if (max_heap > 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("Ergo set NewSize: " SIZE_FORMAT, NewSize);
1230         }
1231       }
1232       // Unless explicitly requested otherwise, size old gen
1233       // so that it's at least 3X of NewSize to begin with;
1234       // later NewRatio will decide how it grows; see above.
1235       if (FLAG_IS_DEFAULT(OldSize)) {
1236         if (max_heap > NewSize) {
1237           FLAG_SET_ERGO(uintx, OldSize, MIN2(3*NewSize, max_heap - NewSize));
1238           if (PrintGCDetails && Verbose) {
1239             // Too early to use gclog_or_tty
1240             tty->print_cr("Ergo set OldSize: " SIZE_FORMAT, OldSize);
1241           }
1242         }
1243       }
1244     }
1245   }
1246   // Unless explicitly requested otherwise, definitely
1247   // promote all objects surviving "tenuring_default" scavenges.
1248   if (FLAG_IS_DEFAULT(MaxTenuringThreshold) &&
1249       FLAG_IS_DEFAULT(SurvivorRatio)) {
1250     FLAG_SET_ERGO(intx, MaxTenuringThreshold, tenuring_default);
1251   }
1252   // If we decided above (or user explicitly requested)
1253   // `promote all' (via MaxTenuringThreshold := 0),
1254   // prefer minuscule survivor spaces so as not to waste
1255   // space for (non-existent) survivors
1256   if (FLAG_IS_DEFAULT(SurvivorRatio) && MaxTenuringThreshold == 0) {
1257     FLAG_SET_ERGO(intx, SurvivorRatio, MAX2((intx)1024, SurvivorRatio));
1258   }
1259   // If OldPLABSize is set and CMSParPromoteBlocksToClaim is not,
1260   // set CMSParPromoteBlocksToClaim equal to OldPLABSize.
1261   // This is done in order to make ParNew+CMS configuration to work
1262   // with YoungPLABSize and OldPLABSize options.
1263   // See CR 6362902.
1264   if (!FLAG_IS_DEFAULT(OldPLABSize)) {
1265     if (FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim)) {
1266       // OldPLABSize is not the default value but CMSParPromoteBlocksToClaim
1267       // is.  In this situtation let CMSParPromoteBlocksToClaim follow
1268       // the value (either from the command line or ergonomics) of
1269       // OldPLABSize.  Following OldPLABSize is an ergonomics decision.
1270       FLAG_SET_ERGO(uintx, CMSParPromoteBlocksToClaim, OldPLABSize);
1271     } else {
1272       // OldPLABSize and CMSParPromoteBlocksToClaim are both set.
1273       // CMSParPromoteBlocksToClaim is a collector-specific flag, so
1274       // we'll let it to take precedence.
1275       jio_fprintf(defaultStream::error_stream(),
1276                   "Both OldPLABSize and CMSParPromoteBlocksToClaim"
1277                   " options are specified for the CMS collector."
1278                   " CMSParPromoteBlocksToClaim will take precedence.\n");
1279     }
1280   }
1281   if (!FLAG_IS_DEFAULT(ResizeOldPLAB) && !ResizeOldPLAB) {
1282     // OldPLAB sizing manually turned off: Use a larger default setting,
1283     // unless it was manually specified. This is because a too-low value
1284     // will slow down scavenges.
1285     if (FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim)) {
1286       FLAG_SET_ERGO(uintx, CMSParPromoteBlocksToClaim, 50); // default value before 6631166
1287     }
1288   }
1289   // Overwrite OldPLABSize which is the variable we will internally use everywhere.
1290   FLAG_SET_ERGO(uintx, OldPLABSize, CMSParPromoteBlocksToClaim);
1291   // If either of the static initialization defaults have changed, note this
1292   // modification.
1293   if (!FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim) || !FLAG_IS_DEFAULT(OldPLABWeight)) {
1294     CFLS_LAB::modify_initialization(OldPLABSize, OldPLABWeight);
1295   }
1296   if (PrintGCDetails && Verbose) {
1297     tty->print_cr("MarkStackSize: %uk  MarkStackSizeMax: %uk",
1298       MarkStackSize / K, MarkStackSizeMax / K);
1299     tty->print_cr("ConcGCThreads: %u", ConcGCThreads);
1300   }
1301 }
1302 #endif // KERNEL
1303 
1304 void set_object_alignment() {
1305   // Object alignment.
1306   assert(is_power_of_2(ObjectAlignmentInBytes), "ObjectAlignmentInBytes must be power of 2");
1307   MinObjAlignmentInBytes     = ObjectAlignmentInBytes;
1308   assert(MinObjAlignmentInBytes >= HeapWordsPerLong * HeapWordSize, "ObjectAlignmentInBytes value is too small");
1309   MinObjAlignment            = MinObjAlignmentInBytes / HeapWordSize;
1310   assert(MinObjAlignmentInBytes == MinObjAlignment * HeapWordSize, "ObjectAlignmentInBytes value is incorrect");
1311   MinObjAlignmentInBytesMask = MinObjAlignmentInBytes - 1;
1312 
1313   LogMinObjAlignmentInBytes  = exact_log2(ObjectAlignmentInBytes);
1314   LogMinObjAlignment         = LogMinObjAlignmentInBytes - LogHeapWordSize;
1315 
1316   // Oop encoding heap max
1317   OopEncodingHeapMax = (uint64_t(max_juint) + 1) << LogMinObjAlignmentInBytes;
1318 
1319 #ifndef KERNEL
1320   // Set CMS global values
1321   CompactibleFreeListSpace::set_cms_values();
1322 #endif // KERNEL
1323 }
1324 
1325 bool verify_object_alignment() {
1326   // Object alignment.
1327   if (!is_power_of_2(ObjectAlignmentInBytes)) {
1328     jio_fprintf(defaultStream::error_stream(),
1329                 "error: ObjectAlignmentInBytes=%d must be power of 2\n",
1330                 (int)ObjectAlignmentInBytes);
1331     return false;
1332   }
1333   if ((int)ObjectAlignmentInBytes < BytesPerLong) {
1334     jio_fprintf(defaultStream::error_stream(),
1335                 "error: ObjectAlignmentInBytes=%d must be greater or equal %d\n",
1336                 (int)ObjectAlignmentInBytes, BytesPerLong);
1337     return false;
1338   }
1339   // It does not make sense to have big object alignment
1340   // since a space lost due to alignment will be greater
1341   // then a saved space from compressed oops.
1342   if ((int)ObjectAlignmentInBytes > 256) {
1343     jio_fprintf(defaultStream::error_stream(),
1344                 "error: ObjectAlignmentInBytes=%d must not be greater then 256\n",
1345                 (int)ObjectAlignmentInBytes);
1346     return false;
1347   }
1348   // In case page size is very small.
1349   if ((int)ObjectAlignmentInBytes >= os::vm_page_size()) {
1350     jio_fprintf(defaultStream::error_stream(),
1351                 "error: ObjectAlignmentInBytes=%d must be less then page size %d\n",
1352                 (int)ObjectAlignmentInBytes, os::vm_page_size());
1353     return false;
1354   }
1355   return true;
1356 }
1357 
1358 inline uintx max_heap_for_compressed_oops() {
1359   // Avoid sign flip.
1360   if (OopEncodingHeapMax < MaxPermSize + os::vm_page_size()) {
1361     return 0;
1362   }
1363   LP64_ONLY(return OopEncodingHeapMax - MaxPermSize - os::vm_page_size());
1364   NOT_LP64(ShouldNotReachHere(); return 0);
1365 }
1366 
1367 bool Arguments::should_auto_select_low_pause_collector() {
1368   if (UseAutoGCSelectPolicy &&
1369       !FLAG_IS_DEFAULT(MaxGCPauseMillis) &&
1370       (MaxGCPauseMillis <= AutoGCSelectPauseMillis)) {
1371     if (PrintGCDetails) {
1372       // Cannot use gclog_or_tty yet.
1373       tty->print_cr("Automatic selection of the low pause collector"
1374        " based on pause goal of %d (ms)", MaxGCPauseMillis);
1375     }
1376     return true;
1377   }
1378   return false;
1379 }
1380 
1381 void Arguments::set_ergonomics_flags() {
1382   // Parallel GC is not compatible with sharing. If one specifies
1383   // that they want sharing explicitly, do not set ergonomics flags.
1384   if (DumpSharedSpaces || ForceSharedSpaces) {
1385     return;
1386   }
1387 
1388   if (os::is_server_class_machine() && !force_client_mode ) {
1389     // If no other collector is requested explicitly,
1390     // let the VM select the collector based on
1391     // machine class and automatic selection policy.
1392     if (!UseSerialGC &&
1393         !UseConcMarkSweepGC &&
1394         !UseG1GC &&
1395         !UseParNewGC &&
1396         !DumpSharedSpaces &&
1397         FLAG_IS_DEFAULT(UseParallelGC)) {
1398       if (should_auto_select_low_pause_collector()) {
1399         FLAG_SET_ERGO(bool, UseConcMarkSweepGC, true);
1400       } else {
1401         FLAG_SET_ERGO(bool, UseParallelGC, true);
1402       }
1403       no_shared_spaces();
1404     }
1405   }
1406 
1407 #ifndef ZERO
1408 #ifdef _LP64
1409   // Check that UseCompressedOops can be set with the max heap size allocated
1410   // by ergonomics.
1411   if (MaxHeapSize <= max_heap_for_compressed_oops()) {
1412 #if !defined(COMPILER1) || defined(TIERED)
1413     if (FLAG_IS_DEFAULT(UseCompressedOops) && !UseG1GC) {
1414       FLAG_SET_ERGO(bool, UseCompressedOops, true);
1415     }
1416 #endif
1417 #ifdef _WIN64
1418     if (UseLargePages && UseCompressedOops) {
1419       // Cannot allocate guard pages for implicit checks in indexed addressing
1420       // mode, when large pages are specified on windows.
1421       // This flag could be switched ON if narrow oop base address is set to 0,
1422       // see code in Universe::initialize_heap().
1423       Universe::set_narrow_oop_use_implicit_null_checks(false);
1424     }
1425 #endif //  _WIN64
1426   } else {
1427     if (UseCompressedOops && !FLAG_IS_DEFAULT(UseCompressedOops)) {
1428       warning("Max heap size too large for Compressed Oops");
1429       FLAG_SET_DEFAULT(UseCompressedOops, false);
1430     }
1431   }
1432   // Also checks that certain machines are slower with compressed oops
1433   // in vm_version initialization code.
1434 #endif // _LP64
1435 #endif // !ZERO
1436 }
1437 
1438 void Arguments::set_parallel_gc_flags() {
1439   assert(UseParallelGC || UseParallelOldGC, "Error");
1440   // If parallel old was requested, automatically enable parallel scavenge.
1441   if (UseParallelOldGC && !UseParallelGC && FLAG_IS_DEFAULT(UseParallelGC)) {
1442     FLAG_SET_DEFAULT(UseParallelGC, true);
1443   }
1444 
1445   // If no heap maximum was requested explicitly, use some reasonable fraction
1446   // of the physical memory, up to a maximum of 1GB.
1447   if (UseParallelGC) {
1448     FLAG_SET_ERGO(uintx, ParallelGCThreads,
1449                   Abstract_VM_Version::parallel_worker_threads());
1450 
1451     // If InitialSurvivorRatio or MinSurvivorRatio were not specified, but the
1452     // SurvivorRatio has been set, reset their default values to SurvivorRatio +
1453     // 2.  By doing this we make SurvivorRatio also work for Parallel Scavenger.
1454     // See CR 6362902 for details.
1455     if (!FLAG_IS_DEFAULT(SurvivorRatio)) {
1456       if (FLAG_IS_DEFAULT(InitialSurvivorRatio)) {
1457          FLAG_SET_DEFAULT(InitialSurvivorRatio, SurvivorRatio + 2);
1458       }
1459       if (FLAG_IS_DEFAULT(MinSurvivorRatio)) {
1460         FLAG_SET_DEFAULT(MinSurvivorRatio, SurvivorRatio + 2);
1461       }
1462     }
1463 
1464     if (UseParallelOldGC) {
1465       // Par compact uses lower default values since they are treated as
1466       // minimums.  These are different defaults because of the different
1467       // interpretation and are not ergonomically set.
1468       if (FLAG_IS_DEFAULT(MarkSweepDeadRatio)) {
1469         FLAG_SET_DEFAULT(MarkSweepDeadRatio, 1);
1470       }
1471       if (FLAG_IS_DEFAULT(PermMarkSweepDeadRatio)) {
1472         FLAG_SET_DEFAULT(PermMarkSweepDeadRatio, 5);
1473       }
1474     }
1475   }
1476 }
1477 
1478 void Arguments::set_g1_gc_flags() {
1479   assert(UseG1GC, "Error");
1480 #ifdef COMPILER1
1481   FastTLABRefill = false;
1482 #endif
1483   FLAG_SET_DEFAULT(ParallelGCThreads,
1484                      Abstract_VM_Version::parallel_worker_threads());
1485   if (ParallelGCThreads == 0) {
1486     FLAG_SET_DEFAULT(ParallelGCThreads,
1487                      Abstract_VM_Version::parallel_worker_threads());
1488   }
1489   no_shared_spaces();
1490 
1491   if (FLAG_IS_DEFAULT(MarkStackSize)) {
1492     FLAG_SET_DEFAULT(MarkStackSize, 128 * TASKQUEUE_SIZE);
1493   }
1494   if (PrintGCDetails && Verbose) {
1495     tty->print_cr("MarkStackSize: %uk  MarkStackSizeMax: %uk",
1496       MarkStackSize / K, MarkStackSizeMax / K);
1497     tty->print_cr("ConcGCThreads: %u", ConcGCThreads);
1498   }
1499 
1500   if (FLAG_IS_DEFAULT(GCTimeRatio) || GCTimeRatio == 0) {
1501     // In G1, we want the default GC overhead goal to be higher than
1502     // say in PS. So we set it here to 10%. Otherwise the heap might
1503     // be expanded more aggressively than we would like it to. In
1504     // fact, even 10% seems to not be high enough in some cases
1505     // (especially small GC stress tests that the main thing they do
1506     // is allocation). We might consider increase it further.
1507     FLAG_SET_DEFAULT(GCTimeRatio, 9);
1508   }
1509 }
1510 
1511 void Arguments::set_heap_size() {
1512   if (!FLAG_IS_DEFAULT(DefaultMaxRAMFraction)) {
1513     // Deprecated flag
1514     FLAG_SET_CMDLINE(uintx, MaxRAMFraction, DefaultMaxRAMFraction);
1515   }
1516 
1517   const julong phys_mem =
1518     FLAG_IS_DEFAULT(MaxRAM) ? MIN2(os::physical_memory(), (julong)MaxRAM)
1519                             : (julong)MaxRAM;
1520 
1521   // If the maximum heap size has not been set with -Xmx,
1522   // then set it as fraction of the size of physical memory,
1523   // respecting the maximum and minimum sizes of the heap.
1524   if (FLAG_IS_DEFAULT(MaxHeapSize)) {
1525     julong reasonable_max = phys_mem / MaxRAMFraction;
1526 
1527     if (phys_mem <= MaxHeapSize * MinRAMFraction) {
1528       // Small physical memory, so use a minimum fraction of it for the heap
1529       reasonable_max = phys_mem / MinRAMFraction;
1530     } else {
1531       // Not-small physical memory, so require a heap at least
1532       // as large as MaxHeapSize
1533       reasonable_max = MAX2(reasonable_max, (julong)MaxHeapSize);
1534     }
1535     if (!FLAG_IS_DEFAULT(ErgoHeapSizeLimit) && ErgoHeapSizeLimit != 0) {
1536       // Limit the heap size to ErgoHeapSizeLimit
1537       reasonable_max = MIN2(reasonable_max, (julong)ErgoHeapSizeLimit);
1538     }
1539     if (UseCompressedOops) {
1540       // Limit the heap size to the maximum possible when using compressed oops
1541       julong max_coop_heap = (julong)max_heap_for_compressed_oops();
1542       if (HeapBaseMinAddress + MaxHeapSize < max_coop_heap) {
1543         // Heap should be above HeapBaseMinAddress to get zero based compressed oops
1544         // but it should be not less than default MaxHeapSize.
1545         max_coop_heap -= HeapBaseMinAddress;
1546       }
1547       reasonable_max = MIN2(reasonable_max, max_coop_heap);
1548     }
1549     reasonable_max = os::allocatable_physical_memory(reasonable_max);
1550 
1551     if (!FLAG_IS_DEFAULT(InitialHeapSize)) {
1552       // An initial heap size was specified on the command line,
1553       // so be sure that the maximum size is consistent.  Done
1554       // after call to allocatable_physical_memory because that
1555       // method might reduce the allocation size.
1556       reasonable_max = MAX2(reasonable_max, (julong)InitialHeapSize);
1557     }
1558 
1559     if (PrintGCDetails && Verbose) {
1560       // Cannot use gclog_or_tty yet.
1561       tty->print_cr("  Maximum heap size " SIZE_FORMAT, reasonable_max);
1562     }
1563     FLAG_SET_ERGO(uintx, MaxHeapSize, (uintx)reasonable_max);
1564   }
1565 
1566   // If the initial_heap_size has not been set with InitialHeapSize
1567   // or -Xms, then set it as fraction of the size of physical memory,
1568   // respecting the maximum and minimum sizes of the heap.
1569   if (FLAG_IS_DEFAULT(InitialHeapSize)) {
1570     julong reasonable_minimum = (julong)(OldSize + NewSize);
1571 
1572     reasonable_minimum = MIN2(reasonable_minimum, (julong)MaxHeapSize);
1573 
1574     reasonable_minimum = os::allocatable_physical_memory(reasonable_minimum);
1575 
1576     julong reasonable_initial = phys_mem / InitialRAMFraction;
1577 
1578     reasonable_initial = MAX2(reasonable_initial, reasonable_minimum);
1579     reasonable_initial = MIN2(reasonable_initial, (julong)MaxHeapSize);
1580 
1581     reasonable_initial = os::allocatable_physical_memory(reasonable_initial);
1582 
1583     if (PrintGCDetails && Verbose) {
1584       // Cannot use gclog_or_tty yet.
1585       tty->print_cr("  Initial heap size " SIZE_FORMAT, (uintx)reasonable_initial);
1586       tty->print_cr("  Minimum heap size " SIZE_FORMAT, (uintx)reasonable_minimum);
1587     }
1588     FLAG_SET_ERGO(uintx, InitialHeapSize, (uintx)reasonable_initial);
1589     set_min_heap_size((uintx)reasonable_minimum);
1590   }
1591 }
1592 
1593 // This must be called after ergonomics because we want bytecode rewriting
1594 // if the server compiler is used, or if UseSharedSpaces is disabled.
1595 void Arguments::set_bytecode_flags() {
1596   // Better not attempt to store into a read-only space.
1597   if (UseSharedSpaces) {
1598     FLAG_SET_DEFAULT(RewriteBytecodes, false);
1599     FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
1600   }
1601 
1602   if (!RewriteBytecodes) {
1603     FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
1604   }
1605 }
1606 
1607 // Aggressive optimization flags  -XX:+AggressiveOpts
1608 void Arguments::set_aggressive_opts_flags() {
1609 #ifdef COMPILER2
1610   if (AggressiveOpts || !FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
1611     if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
1612       FLAG_SET_DEFAULT(EliminateAutoBox, true);
1613     }
1614     if (FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
1615       FLAG_SET_DEFAULT(AutoBoxCacheMax, 20000);
1616     }
1617 
1618     // Feed the cache size setting into the JDK
1619     char buffer[1024];
1620     sprintf(buffer, "java.lang.Integer.IntegerCache.high=" INTX_FORMAT, AutoBoxCacheMax);
1621     add_property(buffer);
1622   }
1623   if (AggressiveOpts && FLAG_IS_DEFAULT(DoEscapeAnalysis)) {
1624     FLAG_SET_DEFAULT(DoEscapeAnalysis, true);
1625   }
1626   if (AggressiveOpts && FLAG_IS_DEFAULT(BiasedLockingStartupDelay)) {
1627     FLAG_SET_DEFAULT(BiasedLockingStartupDelay, 500);
1628   }
1629   if (AggressiveOpts && FLAG_IS_DEFAULT(OptimizeStringConcat)) {
1630     FLAG_SET_DEFAULT(OptimizeStringConcat, true);
1631   }
1632   if (AggressiveOpts && FLAG_IS_DEFAULT(OptimizeFill)) {
1633     FLAG_SET_DEFAULT(OptimizeFill, true);
1634   }
1635 #endif
1636 
1637   if (AggressiveOpts) {
1638 // Sample flag setting code
1639 //    if (FLAG_IS_DEFAULT(EliminateZeroing)) {
1640 //      FLAG_SET_DEFAULT(EliminateZeroing, true);
1641 //    }
1642   }
1643 }
1644 
1645 //===========================================================================================================
1646 // Parsing of java.compiler property
1647 
1648 void Arguments::process_java_compiler_argument(char* arg) {
1649   // For backwards compatibility, Djava.compiler=NONE or ""
1650   // causes us to switch to -Xint mode UNLESS -Xdebug
1651   // is also specified.
1652   if (strlen(arg) == 0 || strcasecmp(arg, "NONE") == 0) {
1653     set_java_compiler(true);    // "-Djava.compiler[=...]" most recently seen.
1654   }
1655 }
1656 
1657 void Arguments::process_java_launcher_argument(const char* launcher, void* extra_info) {
1658   _sun_java_launcher = strdup(launcher);
1659 }
1660 
1661 bool Arguments::created_by_java_launcher() {
1662   assert(_sun_java_launcher != NULL, "property must have value");
1663   return strcmp(DEFAULT_JAVA_LAUNCHER, _sun_java_launcher) != 0;
1664 }
1665 
1666 //===========================================================================================================
1667 // Parsing of main arguments
1668 
1669 bool Arguments::verify_interval(uintx val, uintx min,
1670                                 uintx max, const char* name) {
1671   // Returns true iff value is in the inclusive interval [min..max]
1672   // false, otherwise.
1673   if (val >= min && val <= max) {
1674     return true;
1675   }
1676   jio_fprintf(defaultStream::error_stream(),
1677               "%s of " UINTX_FORMAT " is invalid; must be between " UINTX_FORMAT
1678               " and " UINTX_FORMAT "\n",
1679               name, val, min, max);
1680   return false;
1681 }
1682 
1683 bool Arguments::verify_min_value(intx val, intx min, const char* name) {
1684   // Returns true if given value is greater than specified min threshold
1685   // false, otherwise.
1686   if (val >= min ) {
1687       return true;
1688   }
1689   jio_fprintf(defaultStream::error_stream(),
1690               "%s of " INTX_FORMAT " is invalid; must be greater than " INTX_FORMAT "\n",
1691               name, val, min);
1692   return false;
1693 }
1694 
1695 bool Arguments::verify_percentage(uintx value, const char* name) {
1696   if (value <= 100) {
1697     return true;
1698   }
1699   jio_fprintf(defaultStream::error_stream(),
1700               "%s of " UINTX_FORMAT " is invalid; must be between 0 and 100\n",
1701               name, value);
1702   return false;
1703 }
1704 
1705 static void force_serial_gc() {
1706   FLAG_SET_DEFAULT(UseSerialGC, true);
1707   FLAG_SET_DEFAULT(UseParNewGC, false);
1708   FLAG_SET_DEFAULT(UseConcMarkSweepGC, false);
1709   FLAG_SET_DEFAULT(CMSIncrementalMode, false);  // special CMS suboption
1710   FLAG_SET_DEFAULT(UseParallelGC, false);
1711   FLAG_SET_DEFAULT(UseParallelOldGC, false);
1712   FLAG_SET_DEFAULT(UseG1GC, false);
1713 }
1714 
1715 static bool verify_serial_gc_flags() {
1716   return (UseSerialGC &&
1717         !(UseParNewGC || (UseConcMarkSweepGC || CMSIncrementalMode) || UseG1GC ||
1718           UseParallelGC || UseParallelOldGC));
1719 }
1720 
1721 // Check consistency of GC selection
1722 bool Arguments::check_gc_consistency() {
1723   bool status = true;
1724   // Ensure that the user has not selected conflicting sets
1725   // of collectors. [Note: this check is merely a user convenience;
1726   // collectors over-ride each other so that only a non-conflicting
1727   // set is selected; however what the user gets is not what they
1728   // may have expected from the combination they asked for. It's
1729   // better to reduce user confusion by not allowing them to
1730   // select conflicting combinations.
1731   uint i = 0;
1732   if (UseSerialGC)                       i++;
1733   if (UseConcMarkSweepGC || UseParNewGC) i++;
1734   if (UseParallelGC || UseParallelOldGC) i++;
1735   if (UseG1GC)                           i++;
1736   if (i > 1) {
1737     jio_fprintf(defaultStream::error_stream(),
1738                 "Conflicting collector combinations in option list; "
1739                 "please refer to the release notes for the combinations "
1740                 "allowed\n");
1741     status = false;
1742   }
1743 
1744   return status;
1745 }
1746 
1747 // Check stack pages settings
1748 bool Arguments::check_stack_pages()
1749 {
1750   bool status = true;
1751   status = status && verify_min_value(StackYellowPages, 1, "StackYellowPages");
1752   status = status && verify_min_value(StackRedPages, 1, "StackRedPages");
1753   // greater stack shadow pages can't generate instruction to bang stack
1754   status = status && verify_interval(StackShadowPages, 1, 50, "StackShadowPages");
1755   return status;
1756 }
1757 
1758 // Check the consistency of vm_init_args
1759 bool Arguments::check_vm_args_consistency() {
1760   // Method for adding checks for flag consistency.
1761   // The intent is to warn the user of all possible conflicts,
1762   // before returning an error.
1763   // Note: Needs platform-dependent factoring.
1764   bool status = true;
1765 
1766 #if ( (defined(COMPILER2) && defined(SPARC)))
1767   // NOTE: The call to VM_Version_init depends on the fact that VM_Version_init
1768   // on sparc doesn't require generation of a stub as is the case on, e.g.,
1769   // x86.  Normally, VM_Version_init must be called from init_globals in
1770   // init.cpp, which is called by the initial java thread *after* arguments
1771   // have been parsed.  VM_Version_init gets called twice on sparc.
1772   extern void VM_Version_init();
1773   VM_Version_init();
1774   if (!VM_Version::has_v9()) {
1775     jio_fprintf(defaultStream::error_stream(),
1776                 "V8 Machine detected, Server requires V9\n");
1777     status = false;
1778   }
1779 #endif /* COMPILER2 && SPARC */
1780 
1781   // Allow both -XX:-UseStackBanging and -XX:-UseBoundThreads in non-product
1782   // builds so the cost of stack banging can be measured.
1783 #if (defined(PRODUCT) && defined(SOLARIS))
1784   if (!UseBoundThreads && !UseStackBanging) {
1785     jio_fprintf(defaultStream::error_stream(),
1786                 "-UseStackBanging conflicts with -UseBoundThreads\n");
1787 
1788      status = false;
1789   }
1790 #endif
1791 
1792   if (TLABRefillWasteFraction == 0) {
1793     jio_fprintf(defaultStream::error_stream(),
1794                 "TLABRefillWasteFraction should be a denominator, "
1795                 "not " SIZE_FORMAT "\n",
1796                 TLABRefillWasteFraction);
1797     status = false;
1798   }
1799 
1800   status = status && verify_percentage(AdaptiveSizePolicyWeight,
1801                               "AdaptiveSizePolicyWeight");
1802   status = status && verify_percentage(AdaptivePermSizeWeight, "AdaptivePermSizeWeight");
1803   status = status && verify_percentage(ThresholdTolerance, "ThresholdTolerance");
1804   status = status && verify_percentage(MinHeapFreeRatio, "MinHeapFreeRatio");
1805   status = status && verify_percentage(MaxHeapFreeRatio, "MaxHeapFreeRatio");
1806 
1807   if (MinHeapFreeRatio > MaxHeapFreeRatio) {
1808     jio_fprintf(defaultStream::error_stream(),
1809                 "MinHeapFreeRatio (" UINTX_FORMAT ") must be less than or "
1810                 "equal to MaxHeapFreeRatio (" UINTX_FORMAT ")\n",
1811                 MinHeapFreeRatio, MaxHeapFreeRatio);
1812     status = false;
1813   }
1814   // Keeping the heap 100% free is hard ;-) so limit it to 99%.
1815   MinHeapFreeRatio = MIN2(MinHeapFreeRatio, (uintx) 99);
1816 
1817   if (FullGCALot && FLAG_IS_DEFAULT(MarkSweepAlwaysCompactCount)) {
1818     MarkSweepAlwaysCompactCount = 1;  // Move objects every gc.
1819   }
1820 
1821   if (UseParallelOldGC && ParallelOldGCSplitALot) {
1822     // Settings to encourage splitting.
1823     if (!FLAG_IS_CMDLINE(NewRatio)) {
1824       FLAG_SET_CMDLINE(intx, NewRatio, 2);
1825     }
1826     if (!FLAG_IS_CMDLINE(ScavengeBeforeFullGC)) {
1827       FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
1828     }
1829   }
1830 
1831   status = status && verify_percentage(GCHeapFreeLimit, "GCHeapFreeLimit");
1832   status = status && verify_percentage(GCTimeLimit, "GCTimeLimit");
1833   if (GCTimeLimit == 100) {
1834     // Turn off gc-overhead-limit-exceeded checks
1835     FLAG_SET_DEFAULT(UseGCOverheadLimit, false);
1836   }
1837 
1838   status = status && verify_percentage(GCHeapFreeLimit, "GCHeapFreeLimit");
1839 
1840   // Check whether user-specified sharing option conflicts with GC or page size.
1841   // Both sharing and large pages are enabled by default on some platforms;
1842   // large pages override sharing only if explicitly set on the command line.
1843   const bool cannot_share = UseConcMarkSweepGC || CMSIncrementalMode ||
1844           UseG1GC || UseParNewGC || UseParallelGC || UseParallelOldGC ||
1845           UseLargePages && FLAG_IS_CMDLINE(UseLargePages);
1846   if (cannot_share) {
1847     // Either force sharing on by forcing the other options off, or
1848     // force sharing off.
1849     if (DumpSharedSpaces || ForceSharedSpaces) {
1850       jio_fprintf(defaultStream::error_stream(),
1851                   "Using Serial GC and default page size because of %s\n",
1852                   ForceSharedSpaces ? "-Xshare:on" : "-Xshare:dump");
1853       force_serial_gc();
1854       FLAG_SET_DEFAULT(UseLargePages, false);
1855     } else {
1856       if (UseSharedSpaces && Verbose) {
1857         jio_fprintf(defaultStream::error_stream(),
1858                     "Turning off use of shared archive because of "
1859                     "choice of garbage collector or large pages\n");
1860       }
1861       no_shared_spaces();
1862     }
1863   } else if (UseLargePages && (UseSharedSpaces || DumpSharedSpaces)) {
1864     FLAG_SET_DEFAULT(UseLargePages, false);
1865   }
1866 
1867   status = status && check_gc_consistency();
1868   status = status && check_stack_pages();
1869 
1870   if (_has_alloc_profile) {
1871     if (UseParallelGC || UseParallelOldGC) {
1872       jio_fprintf(defaultStream::error_stream(),
1873                   "error:  invalid argument combination.\n"
1874                   "Allocation profiling (-Xaprof) cannot be used together with "
1875                   "Parallel GC (-XX:+UseParallelGC or -XX:+UseParallelOldGC).\n");
1876       status = false;
1877     }
1878     if (UseConcMarkSweepGC) {
1879       jio_fprintf(defaultStream::error_stream(),
1880                   "error:  invalid argument combination.\n"
1881                   "Allocation profiling (-Xaprof) cannot be used together with "
1882                   "the CMS collector (-XX:+UseConcMarkSweepGC).\n");
1883       status = false;
1884     }
1885   }
1886 
1887   if (CMSIncrementalMode) {
1888     if (!UseConcMarkSweepGC) {
1889       jio_fprintf(defaultStream::error_stream(),
1890                   "error:  invalid argument combination.\n"
1891                   "The CMS collector (-XX:+UseConcMarkSweepGC) must be "
1892                   "selected in order\nto use CMSIncrementalMode.\n");
1893       status = false;
1894     } else {
1895       status = status && verify_percentage(CMSIncrementalDutyCycle,
1896                                   "CMSIncrementalDutyCycle");
1897       status = status && verify_percentage(CMSIncrementalDutyCycleMin,
1898                                   "CMSIncrementalDutyCycleMin");
1899       status = status && verify_percentage(CMSIncrementalSafetyFactor,
1900                                   "CMSIncrementalSafetyFactor");
1901       status = status && verify_percentage(CMSIncrementalOffset,
1902                                   "CMSIncrementalOffset");
1903       status = status && verify_percentage(CMSExpAvgFactor,
1904                                   "CMSExpAvgFactor");
1905       // If it was not set on the command line, set
1906       // CMSInitiatingOccupancyFraction to 1 so icms can initiate cycles early.
1907       if (CMSInitiatingOccupancyFraction < 0) {
1908         FLAG_SET_DEFAULT(CMSInitiatingOccupancyFraction, 1);
1909       }
1910     }
1911   }
1912 
1913   // CMS space iteration, which FLSVerifyAllHeapreferences entails,
1914   // insists that we hold the requisite locks so that the iteration is
1915   // MT-safe. For the verification at start-up and shut-down, we don't
1916   // yet have a good way of acquiring and releasing these locks,
1917   // which are not visible at the CollectedHeap level. We want to
1918   // be able to acquire these locks and then do the iteration rather
1919   // than just disable the lock verification. This will be fixed under
1920   // bug 4788986.
1921   if (UseConcMarkSweepGC && FLSVerifyAllHeapReferences) {
1922     if (VerifyGCStartAt == 0) {
1923       warning("Heap verification at start-up disabled "
1924               "(due to current incompatibility with FLSVerifyAllHeapReferences)");
1925       VerifyGCStartAt = 1;      // Disable verification at start-up
1926     }
1927     if (VerifyBeforeExit) {
1928       warning("Heap verification at shutdown disabled "
1929               "(due to current incompatibility with FLSVerifyAllHeapReferences)");
1930       VerifyBeforeExit = false; // Disable verification at shutdown
1931     }
1932   }
1933 
1934   // Note: only executed in non-PRODUCT mode
1935   if (!UseAsyncConcMarkSweepGC &&
1936       (ExplicitGCInvokesConcurrent ||
1937        ExplicitGCInvokesConcurrentAndUnloadsClasses)) {
1938     jio_fprintf(defaultStream::error_stream(),
1939                 "error: +ExplictGCInvokesConcurrent[AndUnloadsClasses] conflicts"
1940                 " with -UseAsyncConcMarkSweepGC");
1941     status = false;
1942   }
1943 
1944 #ifndef SERIALGC
1945   if (UseG1GC) {
1946     status = status && verify_percentage(InitiatingHeapOccupancyPercent,
1947                                          "InitiatingHeapOccupancyPercent");
1948     status = status && verify_min_value(G1RefProcDrainInterval, 1,
1949                                         "G1RefProcDrainInterval");
1950     status = status && verify_min_value((intx)G1ConcMarkStepDurationMillis, 1,
1951                                         "G1ConcMarkStepDurationMillis");
1952   }
1953 #endif
1954 
1955   status = status && verify_interval(RefDiscoveryPolicy,
1956                                      ReferenceProcessor::DiscoveryPolicyMin,
1957                                      ReferenceProcessor::DiscoveryPolicyMax,
1958                                      "RefDiscoveryPolicy");
1959 
1960   // Limit the lower bound of this flag to 1 as it is used in a division
1961   // expression.
1962   status = status && verify_interval(TLABWasteTargetPercent,
1963                                      1, 100, "TLABWasteTargetPercent");
1964 
1965   status = status && verify_object_alignment();
1966 
1967   return status;
1968 }
1969 
1970 bool Arguments::is_bad_option(const JavaVMOption* option, jboolean ignore,
1971   const char* option_type) {
1972   if (ignore) return false;
1973 
1974   const char* spacer = " ";
1975   if (option_type == NULL) {
1976     option_type = ++spacer; // Set both to the empty string.
1977   }
1978 
1979   if (os::obsolete_option(option)) {
1980     jio_fprintf(defaultStream::error_stream(),
1981                 "Obsolete %s%soption: %s\n", option_type, spacer,
1982       option->optionString);
1983     return false;
1984   } else {
1985     jio_fprintf(defaultStream::error_stream(),
1986                 "Unrecognized %s%soption: %s\n", option_type, spacer,
1987       option->optionString);
1988     return true;
1989   }
1990 }
1991 
1992 static const char* user_assertion_options[] = {
1993   "-da", "-ea", "-disableassertions", "-enableassertions", 0
1994 };
1995 
1996 static const char* system_assertion_options[] = {
1997   "-dsa", "-esa", "-disablesystemassertions", "-enablesystemassertions", 0
1998 };
1999 
2000 // Return true if any of the strings in null-terminated array 'names' matches.
2001 // If tail_allowed is true, then the tail must begin with a colon; otherwise,
2002 // the option must match exactly.
2003 static bool match_option(const JavaVMOption* option, const char** names, const char** tail,
2004   bool tail_allowed) {
2005   for (/* empty */; *names != NULL; ++names) {
2006     if (match_option(option, *names, tail)) {
2007       if (**tail == '\0' || tail_allowed && **tail == ':') {
2008         return true;
2009       }
2010     }
2011   }
2012   return false;
2013 }
2014 
2015 bool Arguments::parse_uintx(const char* value,
2016                             uintx* uintx_arg,
2017                             uintx min_size) {
2018 
2019   // Check the sign first since atomull() parses only unsigned values.
2020   bool value_is_positive = !(*value == '-');
2021 
2022   if (value_is_positive) {
2023     julong n;
2024     bool good_return = atomull(value, &n);
2025     if (good_return) {
2026       bool above_minimum = n >= min_size;
2027       bool value_is_too_large = n > max_uintx;
2028 
2029       if (above_minimum && !value_is_too_large) {
2030         *uintx_arg = n;
2031         return true;
2032       }
2033     }
2034   }
2035   return false;
2036 }
2037 
2038 Arguments::ArgsRange Arguments::parse_memory_size(const char* s,
2039                                                   julong* long_arg,
2040                                                   julong min_size) {
2041   if (!atomull(s, long_arg)) return arg_unreadable;
2042   return check_memory_size(*long_arg, min_size);
2043 }
2044 
2045 // Parse JavaVMInitArgs structure
2046 
2047 jint Arguments::parse_vm_init_args(const JavaVMInitArgs* args) {
2048   // For components of the system classpath.
2049   SysClassPath scp(Arguments::get_sysclasspath());
2050   bool scp_assembly_required = false;
2051 
2052   // Save default settings for some mode flags
2053   Arguments::_AlwaysCompileLoopMethods = AlwaysCompileLoopMethods;
2054   Arguments::_UseOnStackReplacement    = UseOnStackReplacement;
2055   Arguments::_ClipInlining             = ClipInlining;
2056   Arguments::_BackgroundCompilation    = BackgroundCompilation;
2057 
2058   // Parse JAVA_TOOL_OPTIONS environment variable (if present)
2059   jint result = parse_java_tool_options_environment_variable(&scp, &scp_assembly_required);
2060   if (result != JNI_OK) {
2061     return result;
2062   }
2063 
2064   // Parse JavaVMInitArgs structure passed in
2065   result = parse_each_vm_init_arg(args, &scp, &scp_assembly_required, COMMAND_LINE);
2066   if (result != JNI_OK) {
2067     return result;
2068   }
2069 
2070   if (AggressiveOpts) {
2071     // Insert alt-rt.jar between user-specified bootclasspath
2072     // prefix and the default bootclasspath.  os::set_boot_path()
2073     // uses meta_index_dir as the default bootclasspath directory.
2074     const char* altclasses_jar = "alt-rt.jar";
2075     size_t altclasses_path_len = strlen(get_meta_index_dir()) + 1 +
2076                                  strlen(altclasses_jar);
2077     char* altclasses_path = NEW_C_HEAP_ARRAY(char, altclasses_path_len);
2078     strcpy(altclasses_path, get_meta_index_dir());
2079     strcat(altclasses_path, altclasses_jar);
2080     scp.add_suffix_to_prefix(altclasses_path);
2081     scp_assembly_required = true;
2082     FREE_C_HEAP_ARRAY(char, altclasses_path);
2083   }
2084 
2085   // Parse _JAVA_OPTIONS environment variable (if present) (mimics classic VM)
2086   result = parse_java_options_environment_variable(&scp, &scp_assembly_required);
2087   if (result != JNI_OK) {
2088     return result;
2089   }
2090 
2091   // Do final processing now that all arguments have been parsed
2092   result = finalize_vm_init_args(&scp, scp_assembly_required);
2093   if (result != JNI_OK) {
2094     return result;
2095   }
2096 
2097   return JNI_OK;
2098 }
2099 
2100 jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args,
2101                                        SysClassPath* scp_p,
2102                                        bool* scp_assembly_required_p,
2103                                        FlagValueOrigin origin) {
2104   // Remaining part of option string
2105   const char* tail;
2106 
2107   // iterate over arguments
2108   for (int index = 0; index < args->nOptions; index++) {
2109     bool is_absolute_path = false;  // for -agentpath vs -agentlib
2110 
2111     const JavaVMOption* option = args->options + index;
2112 
2113     if (!match_option(option, "-Djava.class.path", &tail) &&
2114         !match_option(option, "-Dsun.java.command", &tail) &&
2115         !match_option(option, "-Dsun.java.launcher", &tail)) {
2116 
2117         // add all jvm options to the jvm_args string. This string
2118         // is used later to set the java.vm.args PerfData string constant.
2119         // the -Djava.class.path and the -Dsun.java.command options are
2120         // omitted from jvm_args string as each have their own PerfData
2121         // string constant object.
2122         build_jvm_args(option->optionString);
2123     }
2124 
2125     // -verbose:[class/gc/jni]
2126     if (match_option(option, "-verbose", &tail)) {
2127       if (!strcmp(tail, ":class") || !strcmp(tail, "")) {
2128         FLAG_SET_CMDLINE(bool, TraceClassLoading, true);
2129         FLAG_SET_CMDLINE(bool, TraceClassUnloading, true);
2130       } else if (!strcmp(tail, ":gc")) {
2131         FLAG_SET_CMDLINE(bool, PrintGC, true);
2132       } else if (!strcmp(tail, ":jni")) {
2133         FLAG_SET_CMDLINE(bool, PrintJNIResolving, true);
2134       }
2135     // -da / -ea / -disableassertions / -enableassertions
2136     // These accept an optional class/package name separated by a colon, e.g.,
2137     // -da:java.lang.Thread.
2138     } else if (match_option(option, user_assertion_options, &tail, true)) {
2139       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2140       if (*tail == '\0') {
2141         JavaAssertions::setUserClassDefault(enable);
2142       } else {
2143         assert(*tail == ':', "bogus match by match_option()");
2144         JavaAssertions::addOption(tail + 1, enable);
2145       }
2146     // -dsa / -esa / -disablesystemassertions / -enablesystemassertions
2147     } else if (match_option(option, system_assertion_options, &tail, false)) {
2148       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2149       JavaAssertions::setSystemClassDefault(enable);
2150     // -bootclasspath:
2151     } else if (match_option(option, "-Xbootclasspath:", &tail)) {
2152       scp_p->reset_path(tail);
2153       *scp_assembly_required_p = true;
2154     // -bootclasspath/a:
2155     } else if (match_option(option, "-Xbootclasspath/a:", &tail)) {
2156       scp_p->add_suffix(tail);
2157       *scp_assembly_required_p = true;
2158     // -bootclasspath/p:
2159     } else if (match_option(option, "-Xbootclasspath/p:", &tail)) {
2160       scp_p->add_prefix(tail);
2161       *scp_assembly_required_p = true;
2162     // -Xrun
2163     } else if (match_option(option, "-Xrun", &tail)) {
2164       if (tail != NULL) {
2165         const char* pos = strchr(tail, ':');
2166         size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
2167         char* name = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len + 1), tail, len);
2168         name[len] = '\0';
2169 
2170         char *options = NULL;
2171         if(pos != NULL) {
2172           size_t len2 = strlen(pos+1) + 1; // options start after ':'.  Final zero must be copied.
2173           options = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len2), pos+1, len2);
2174         }
2175 #ifdef JVMTI_KERNEL
2176         if ((strcmp(name, "hprof") == 0) || (strcmp(name, "jdwp") == 0)) {
2177           warning("profiling and debugging agents are not supported with Kernel VM");
2178         } else
2179 #endif // JVMTI_KERNEL
2180         add_init_library(name, options);
2181       }
2182     // -agentlib and -agentpath
2183     } else if (match_option(option, "-agentlib:", &tail) ||
2184           (is_absolute_path = match_option(option, "-agentpath:", &tail))) {
2185       if(tail != NULL) {
2186         const char* pos = strchr(tail, '=');
2187         size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
2188         char* name = strncpy(NEW_C_HEAP_ARRAY(char, len + 1), tail, len);
2189         name[len] = '\0';
2190 
2191         char *options = NULL;
2192         if(pos != NULL) {
2193           options = strcpy(NEW_C_HEAP_ARRAY(char, strlen(pos + 1) + 1), pos + 1);
2194         }
2195 #ifdef JVMTI_KERNEL
2196         if ((strcmp(name, "hprof") == 0) || (strcmp(name, "jdwp") == 0)) {
2197           warning("profiling and debugging agents are not supported with Kernel VM");
2198         } else
2199 #endif // JVMTI_KERNEL
2200         add_init_agent(name, options, is_absolute_path);
2201 
2202       }
2203     // -javaagent
2204     } else if (match_option(option, "-javaagent:", &tail)) {
2205       if(tail != NULL) {
2206         char *options = strcpy(NEW_C_HEAP_ARRAY(char, strlen(tail) + 1), tail);
2207         add_init_agent("instrument", options, false);
2208       }
2209     // -Xnoclassgc
2210     } else if (match_option(option, "-Xnoclassgc", &tail)) {
2211       FLAG_SET_CMDLINE(bool, ClassUnloading, false);
2212     // -Xincgc: i-CMS
2213     } else if (match_option(option, "-Xincgc", &tail)) {
2214       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, true);
2215       FLAG_SET_CMDLINE(bool, CMSIncrementalMode, true);
2216     // -Xnoincgc: no i-CMS
2217     } else if (match_option(option, "-Xnoincgc", &tail)) {
2218       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, false);
2219       FLAG_SET_CMDLINE(bool, CMSIncrementalMode, false);
2220     // -Xconcgc
2221     } else if (match_option(option, "-Xconcgc", &tail)) {
2222       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, true);
2223     // -Xnoconcgc
2224     } else if (match_option(option, "-Xnoconcgc", &tail)) {
2225       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, false);
2226     // -Xbatch
2227     } else if (match_option(option, "-Xbatch", &tail)) {
2228       FLAG_SET_CMDLINE(bool, BackgroundCompilation, false);
2229     // -Xmn for compatibility with other JVM vendors
2230     } else if (match_option(option, "-Xmn", &tail)) {
2231       julong long_initial_eden_size = 0;
2232       ArgsRange errcode = parse_memory_size(tail, &long_initial_eden_size, 1);
2233       if (errcode != arg_in_range) {
2234         jio_fprintf(defaultStream::error_stream(),
2235                     "Invalid initial eden size: %s\n", option->optionString);
2236         describe_range_error(errcode);
2237         return JNI_EINVAL;
2238       }
2239       FLAG_SET_CMDLINE(uintx, MaxNewSize, (uintx)long_initial_eden_size);
2240       FLAG_SET_CMDLINE(uintx, NewSize, (uintx)long_initial_eden_size);
2241     // -Xms
2242     } else if (match_option(option, "-Xms", &tail)) {
2243       julong long_initial_heap_size = 0;
2244       ArgsRange errcode = parse_memory_size(tail, &long_initial_heap_size, 1);
2245       if (errcode != arg_in_range) {
2246         jio_fprintf(defaultStream::error_stream(),
2247                     "Invalid initial heap size: %s\n", option->optionString);
2248         describe_range_error(errcode);
2249         return JNI_EINVAL;
2250       }
2251       FLAG_SET_CMDLINE(uintx, InitialHeapSize, (uintx)long_initial_heap_size);
2252       // Currently the minimum size and the initial heap sizes are the same.
2253       set_min_heap_size(InitialHeapSize);
2254     // -Xmx
2255     } else if (match_option(option, "-Xmx", &tail)) {
2256       julong long_max_heap_size = 0;
2257       ArgsRange errcode = parse_memory_size(tail, &long_max_heap_size, 1);
2258       if (errcode != arg_in_range) {
2259         jio_fprintf(defaultStream::error_stream(),
2260                     "Invalid maximum heap size: %s\n", option->optionString);
2261         describe_range_error(errcode);
2262         return JNI_EINVAL;
2263       }
2264       FLAG_SET_CMDLINE(uintx, MaxHeapSize, (uintx)long_max_heap_size);
2265     // Xmaxf
2266     } else if (match_option(option, "-Xmaxf", &tail)) {
2267       int maxf = (int)(atof(tail) * 100);
2268       if (maxf < 0 || maxf > 100) {
2269         jio_fprintf(defaultStream::error_stream(),
2270                     "Bad max heap free percentage size: %s\n",
2271                     option->optionString);
2272         return JNI_EINVAL;
2273       } else {
2274         FLAG_SET_CMDLINE(uintx, MaxHeapFreeRatio, maxf);
2275       }
2276     // Xminf
2277     } else if (match_option(option, "-Xminf", &tail)) {
2278       int minf = (int)(atof(tail) * 100);
2279       if (minf < 0 || minf > 100) {
2280         jio_fprintf(defaultStream::error_stream(),
2281                     "Bad min heap free percentage size: %s\n",
2282                     option->optionString);
2283         return JNI_EINVAL;
2284       } else {
2285         FLAG_SET_CMDLINE(uintx, MinHeapFreeRatio, minf);
2286       }
2287     // -Xss
2288     } else if (match_option(option, "-Xss", &tail)) {
2289       julong long_ThreadStackSize = 0;
2290       ArgsRange errcode = parse_memory_size(tail, &long_ThreadStackSize, 1000);
2291       if (errcode != arg_in_range) {
2292         jio_fprintf(defaultStream::error_stream(),
2293                     "Invalid thread stack size: %s\n", option->optionString);
2294         describe_range_error(errcode);
2295         return JNI_EINVAL;
2296       }
2297       // Internally track ThreadStackSize in units of 1024 bytes.
2298       FLAG_SET_CMDLINE(intx, ThreadStackSize,
2299                               round_to((int)long_ThreadStackSize, K) / K);
2300     // -Xoss
2301     } else if (match_option(option, "-Xoss", &tail)) {
2302           // HotSpot does not have separate native and Java stacks, ignore silently for compatibility
2303     // -Xmaxjitcodesize
2304     } else if (match_option(option, "-Xmaxjitcodesize", &tail) ||
2305                match_option(option, "-XX:ReservedCodeCacheSize=", &tail)) {
2306       julong long_ReservedCodeCacheSize = 0;
2307       ArgsRange errcode = parse_memory_size(tail, &long_ReservedCodeCacheSize,
2308                                             (size_t)InitialCodeCacheSize);
2309       if (errcode != arg_in_range) {
2310         jio_fprintf(defaultStream::error_stream(),
2311                     "Invalid maximum code cache size: %s. Should be greater than InitialCodeCacheSize=%dK\n",
2312                     option->optionString, InitialCodeCacheSize/K);
2313         describe_range_error(errcode);
2314         return JNI_EINVAL;
2315       }
2316       FLAG_SET_CMDLINE(uintx, ReservedCodeCacheSize, (uintx)long_ReservedCodeCacheSize);
2317     // -green
2318     } else if (match_option(option, "-green", &tail)) {
2319       jio_fprintf(defaultStream::error_stream(),
2320                   "Green threads support not available\n");
2321           return JNI_EINVAL;
2322     // -native
2323     } else if (match_option(option, "-native", &tail)) {
2324           // HotSpot always uses native threads, ignore silently for compatibility
2325     // -Xsqnopause
2326     } else if (match_option(option, "-Xsqnopause", &tail)) {
2327           // EVM option, ignore silently for compatibility
2328     // -Xrs
2329     } else if (match_option(option, "-Xrs", &tail)) {
2330           // Classic/EVM option, new functionality
2331       FLAG_SET_CMDLINE(bool, ReduceSignalUsage, true);
2332     } else if (match_option(option, "-Xusealtsigs", &tail)) {
2333           // change default internal VM signals used - lower case for back compat
2334       FLAG_SET_CMDLINE(bool, UseAltSigs, true);
2335     // -Xoptimize
2336     } else if (match_option(option, "-Xoptimize", &tail)) {
2337           // EVM option, ignore silently for compatibility
2338     // -Xprof
2339     } else if (match_option(option, "-Xprof", &tail)) {
2340 #ifndef FPROF_KERNEL
2341       _has_profile = true;
2342 #else // FPROF_KERNEL
2343       // do we have to exit?
2344       warning("Kernel VM does not support flat profiling.");
2345 #endif // FPROF_KERNEL
2346     // -Xaprof
2347     } else if (match_option(option, "-Xaprof", &tail)) {
2348       _has_alloc_profile = true;
2349     // -Xconcurrentio
2350     } else if (match_option(option, "-Xconcurrentio", &tail)) {
2351       FLAG_SET_CMDLINE(bool, UseLWPSynchronization, true);
2352       FLAG_SET_CMDLINE(bool, BackgroundCompilation, false);
2353       FLAG_SET_CMDLINE(intx, DeferThrSuspendLoopCount, 1);
2354       FLAG_SET_CMDLINE(bool, UseTLAB, false);
2355       FLAG_SET_CMDLINE(uintx, NewSizeThreadIncrease, 16 * K);  // 20Kb per thread added to new generation
2356 
2357       // -Xinternalversion
2358     } else if (match_option(option, "-Xinternalversion", &tail)) {
2359       jio_fprintf(defaultStream::output_stream(), "%s\n",
2360                   VM_Version::internal_vm_info_string());
2361       vm_exit(0);
2362 #ifndef PRODUCT
2363     // -Xprintflags
2364     } else if (match_option(option, "-Xprintflags", &tail)) {
2365       CommandLineFlags::printFlags();
2366       vm_exit(0);
2367 #endif
2368     // -D
2369     } else if (match_option(option, "-D", &tail)) {
2370       if (!add_property(tail)) {
2371         return JNI_ENOMEM;
2372       }
2373       // Out of the box management support
2374       if (match_option(option, "-Dcom.sun.management", &tail)) {
2375         FLAG_SET_CMDLINE(bool, ManagementServer, true);
2376       }
2377     // -Xint
2378     } else if (match_option(option, "-Xint", &tail)) {
2379           set_mode_flags(_int);
2380     // -Xmixed
2381     } else if (match_option(option, "-Xmixed", &tail)) {
2382           set_mode_flags(_mixed);
2383     // -Xcomp
2384     } else if (match_option(option, "-Xcomp", &tail)) {
2385       // for testing the compiler; turn off all flags that inhibit compilation
2386           set_mode_flags(_comp);
2387 
2388     // -Xshare:dump
2389     } else if (match_option(option, "-Xshare:dump", &tail)) {
2390 #ifdef TIERED
2391       FLAG_SET_CMDLINE(bool, DumpSharedSpaces, true);
2392       set_mode_flags(_int);     // Prevent compilation, which creates objects
2393 #elif defined(COMPILER2)
2394       vm_exit_during_initialization(
2395           "Dumping a shared archive is not supported on the Server JVM.", NULL);
2396 #elif defined(KERNEL)
2397       vm_exit_during_initialization(
2398           "Dumping a shared archive is not supported on the Kernel JVM.", NULL);
2399 #else
2400       FLAG_SET_CMDLINE(bool, DumpSharedSpaces, true);
2401       set_mode_flags(_int);     // Prevent compilation, which creates objects
2402 #endif
2403     // -Xshare:on
2404     } else if (match_option(option, "-Xshare:on", &tail)) {
2405       FLAG_SET_CMDLINE(bool, UseSharedSpaces, true);
2406       FLAG_SET_CMDLINE(bool, RequireSharedSpaces, true);
2407 #ifdef TIERED
2408       FLAG_SET_CMDLINE(bool, ForceSharedSpaces, true);
2409 #endif // TIERED
2410     // -Xshare:auto
2411     } else if (match_option(option, "-Xshare:auto", &tail)) {
2412       FLAG_SET_CMDLINE(bool, UseSharedSpaces, true);
2413       FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false);
2414     // -Xshare:off
2415     } else if (match_option(option, "-Xshare:off", &tail)) {
2416       FLAG_SET_CMDLINE(bool, UseSharedSpaces, false);
2417       FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false);
2418 
2419     // -Xverify
2420     } else if (match_option(option, "-Xverify", &tail)) {
2421       if (strcmp(tail, ":all") == 0 || strcmp(tail, "") == 0) {
2422         FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, true);
2423         FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true);
2424       } else if (strcmp(tail, ":remote") == 0) {
2425         FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false);
2426         FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true);
2427       } else if (strcmp(tail, ":none") == 0) {
2428         FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false);
2429         FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, false);
2430       } else if (is_bad_option(option, args->ignoreUnrecognized, "verification")) {
2431         return JNI_EINVAL;
2432       }
2433     // -Xdebug
2434     } else if (match_option(option, "-Xdebug", &tail)) {
2435       // note this flag has been used, then ignore
2436       set_xdebug_mode(true);
2437     // -Xnoagent
2438     } else if (match_option(option, "-Xnoagent", &tail)) {
2439       // For compatibility with classic. HotSpot refuses to load the old style agent.dll.
2440     } else if (match_option(option, "-Xboundthreads", &tail)) {
2441       // Bind user level threads to kernel threads (Solaris only)
2442       FLAG_SET_CMDLINE(bool, UseBoundThreads, true);
2443     } else if (match_option(option, "-Xloggc:", &tail)) {
2444       // Redirect GC output to the file. -Xloggc:<filename>
2445       // ostream_init_log(), when called will use this filename
2446       // to initialize a fileStream.
2447       _gc_log_filename = strdup(tail);
2448       FLAG_SET_CMDLINE(bool, PrintGC, true);
2449       FLAG_SET_CMDLINE(bool, PrintGCTimeStamps, true);
2450       FLAG_SET_CMDLINE(bool, TraceClassUnloading, true);
2451 
2452     // JNI hooks
2453     } else if (match_option(option, "-Xcheck", &tail)) {
2454       if (!strcmp(tail, ":jni")) {
2455         CheckJNICalls = true;
2456       } else if (is_bad_option(option, args->ignoreUnrecognized,
2457                                      "check")) {
2458         return JNI_EINVAL;
2459       }
2460     } else if (match_option(option, "vfprintf", &tail)) {
2461       _vfprintf_hook = CAST_TO_FN_PTR(vfprintf_hook_t, option->extraInfo);
2462     } else if (match_option(option, "exit", &tail)) {
2463       _exit_hook = CAST_TO_FN_PTR(exit_hook_t, option->extraInfo);
2464     } else if (match_option(option, "abort", &tail)) {
2465       _abort_hook = CAST_TO_FN_PTR(abort_hook_t, option->extraInfo);
2466     // -XX:+AggressiveHeap
2467     } else if (match_option(option, "-XX:+AggressiveHeap", &tail)) {
2468 
2469       // This option inspects the machine and attempts to set various
2470       // parameters to be optimal for long-running, memory allocation
2471       // intensive jobs.  It is intended for machines with large
2472       // amounts of cpu and memory.
2473 
2474       // initHeapSize is needed since _initial_heap_size is 4 bytes on a 32 bit
2475       // VM, but we may not be able to represent the total physical memory
2476       // available (like having 8gb of memory on a box but using a 32bit VM).
2477       // Thus, we need to make sure we're using a julong for intermediate
2478       // calculations.
2479       julong initHeapSize;
2480       julong total_memory = os::physical_memory();
2481 
2482       if (total_memory < (julong)256*M) {
2483         jio_fprintf(defaultStream::error_stream(),
2484                     "You need at least 256mb of memory to use -XX:+AggressiveHeap\n");
2485         vm_exit(1);
2486       }
2487 
2488       // The heap size is half of available memory, or (at most)
2489       // all of possible memory less 160mb (leaving room for the OS
2490       // when using ISM).  This is the maximum; because adaptive sizing
2491       // is turned on below, the actual space used may be smaller.
2492 
2493       initHeapSize = MIN2(total_memory / (julong)2,
2494                           total_memory - (julong)160*M);
2495 
2496       // Make sure that if we have a lot of memory we cap the 32 bit
2497       // process space.  The 64bit VM version of this function is a nop.
2498       initHeapSize = os::allocatable_physical_memory(initHeapSize);
2499 
2500       // The perm gen is separate but contiguous with the
2501       // object heap (and is reserved with it) so subtract it
2502       // from the heap size.
2503       if (initHeapSize > MaxPermSize) {
2504         initHeapSize = initHeapSize - MaxPermSize;
2505       } else {
2506         warning("AggressiveHeap and MaxPermSize values may conflict");
2507       }
2508 
2509       if (FLAG_IS_DEFAULT(MaxHeapSize)) {
2510          FLAG_SET_CMDLINE(uintx, MaxHeapSize, initHeapSize);
2511          FLAG_SET_CMDLINE(uintx, InitialHeapSize, initHeapSize);
2512          // Currently the minimum size and the initial heap sizes are the same.
2513          set_min_heap_size(initHeapSize);
2514       }
2515       if (FLAG_IS_DEFAULT(NewSize)) {
2516          // Make the young generation 3/8ths of the total heap.
2517          FLAG_SET_CMDLINE(uintx, NewSize,
2518                                 ((julong)MaxHeapSize / (julong)8) * (julong)3);
2519          FLAG_SET_CMDLINE(uintx, MaxNewSize, NewSize);
2520       }
2521 
2522       FLAG_SET_DEFAULT(UseLargePages, true);
2523 
2524       // Increase some data structure sizes for efficiency
2525       FLAG_SET_CMDLINE(uintx, BaseFootPrintEstimate, MaxHeapSize);
2526       FLAG_SET_CMDLINE(bool, ResizeTLAB, false);
2527       FLAG_SET_CMDLINE(uintx, TLABSize, 256*K);
2528 
2529       // See the OldPLABSize comment below, but replace 'after promotion'
2530       // with 'after copying'.  YoungPLABSize is the size of the survivor
2531       // space per-gc-thread buffers.  The default is 4kw.
2532       FLAG_SET_CMDLINE(uintx, YoungPLABSize, 256*K);      // Note: this is in words
2533 
2534       // OldPLABSize is the size of the buffers in the old gen that
2535       // UseParallelGC uses to promote live data that doesn't fit in the
2536       // survivor spaces.  At any given time, there's one for each gc thread.
2537       // The default size is 1kw. These buffers are rarely used, since the
2538       // survivor spaces are usually big enough.  For specjbb, however, there
2539       // are occasions when there's lots of live data in the young gen
2540       // and we end up promoting some of it.  We don't have a definite
2541       // explanation for why bumping OldPLABSize helps, but the theory
2542       // is that a bigger PLAB results in retaining something like the
2543       // original allocation order after promotion, which improves mutator
2544       // locality.  A minor effect may be that larger PLABs reduce the
2545       // number of PLAB allocation events during gc.  The value of 8kw
2546       // was arrived at by experimenting with specjbb.
2547       FLAG_SET_CMDLINE(uintx, OldPLABSize, 8*K);  // Note: this is in words
2548 
2549       // CompilationPolicyChoice=0 causes the server compiler to adopt
2550       // a more conservative which-method-do-I-compile policy when one
2551       // of the counters maintained by the interpreter trips.  The
2552       // result is reduced startup time and improved specjbb and
2553       // alacrity performance.  Zero is the default, but we set it
2554       // explicitly here in case the default changes.
2555       // See runtime/compilationPolicy.*.
2556       FLAG_SET_CMDLINE(intx, CompilationPolicyChoice, 0);
2557 
2558       // Enable parallel GC and adaptive generation sizing
2559       FLAG_SET_CMDLINE(bool, UseParallelGC, true);
2560       FLAG_SET_DEFAULT(ParallelGCThreads,
2561                        Abstract_VM_Version::parallel_worker_threads());
2562 
2563       // Encourage steady state memory management
2564       FLAG_SET_CMDLINE(uintx, ThresholdTolerance, 100);
2565 
2566       // This appears to improve mutator locality
2567       FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
2568 
2569       // Get around early Solaris scheduling bug
2570       // (affinity vs other jobs on system)
2571       // but disallow DR and offlining (5008695).
2572       FLAG_SET_CMDLINE(bool, BindGCTaskThreadsToCPUs, true);
2573 
2574     } else if (match_option(option, "-XX:+NeverTenure", &tail)) {
2575       // The last option must always win.
2576       FLAG_SET_CMDLINE(bool, AlwaysTenure, false);
2577       FLAG_SET_CMDLINE(bool, NeverTenure, true);
2578     } else if (match_option(option, "-XX:+AlwaysTenure", &tail)) {
2579       // The last option must always win.
2580       FLAG_SET_CMDLINE(bool, NeverTenure, false);
2581       FLAG_SET_CMDLINE(bool, AlwaysTenure, true);
2582     } else if (match_option(option, "-XX:+CMSPermGenSweepingEnabled", &tail) ||
2583                match_option(option, "-XX:-CMSPermGenSweepingEnabled", &tail)) {
2584       jio_fprintf(defaultStream::error_stream(),
2585         "Please use CMSClassUnloadingEnabled in place of "
2586         "CMSPermGenSweepingEnabled in the future\n");
2587     } else if (match_option(option, "-XX:+UseGCTimeLimit", &tail)) {
2588       FLAG_SET_CMDLINE(bool, UseGCOverheadLimit, true);
2589       jio_fprintf(defaultStream::error_stream(),
2590         "Please use -XX:+UseGCOverheadLimit in place of "
2591         "-XX:+UseGCTimeLimit in the future\n");
2592     } else if (match_option(option, "-XX:-UseGCTimeLimit", &tail)) {
2593       FLAG_SET_CMDLINE(bool, UseGCOverheadLimit, false);
2594       jio_fprintf(defaultStream::error_stream(),
2595         "Please use -XX:-UseGCOverheadLimit in place of "
2596         "-XX:-UseGCTimeLimit in the future\n");
2597     // The TLE options are for compatibility with 1.3 and will be
2598     // removed without notice in a future release.  These options
2599     // are not to be documented.
2600     } else if (match_option(option, "-XX:MaxTLERatio=", &tail)) {
2601       // No longer used.
2602     } else if (match_option(option, "-XX:+ResizeTLE", &tail)) {
2603       FLAG_SET_CMDLINE(bool, ResizeTLAB, true);
2604     } else if (match_option(option, "-XX:-ResizeTLE", &tail)) {
2605       FLAG_SET_CMDLINE(bool, ResizeTLAB, false);
2606     } else if (match_option(option, "-XX:+PrintTLE", &tail)) {
2607       FLAG_SET_CMDLINE(bool, PrintTLAB, true);
2608     } else if (match_option(option, "-XX:-PrintTLE", &tail)) {
2609       FLAG_SET_CMDLINE(bool, PrintTLAB, false);
2610     } else if (match_option(option, "-XX:TLEFragmentationRatio=", &tail)) {
2611       // No longer used.
2612     } else if (match_option(option, "-XX:TLESize=", &tail)) {
2613       julong long_tlab_size = 0;
2614       ArgsRange errcode = parse_memory_size(tail, &long_tlab_size, 1);
2615       if (errcode != arg_in_range) {
2616         jio_fprintf(defaultStream::error_stream(),
2617                     "Invalid TLAB size: %s\n", option->optionString);
2618         describe_range_error(errcode);
2619         return JNI_EINVAL;
2620       }
2621       FLAG_SET_CMDLINE(uintx, TLABSize, long_tlab_size);
2622     } else if (match_option(option, "-XX:TLEThreadRatio=", &tail)) {
2623       // No longer used.
2624     } else if (match_option(option, "-XX:+UseTLE", &tail)) {
2625       FLAG_SET_CMDLINE(bool, UseTLAB, true);
2626     } else if (match_option(option, "-XX:-UseTLE", &tail)) {
2627       FLAG_SET_CMDLINE(bool, UseTLAB, false);
2628 SOLARIS_ONLY(
2629     } else if (match_option(option, "-XX:+UsePermISM", &tail)) {
2630       warning("-XX:+UsePermISM is obsolete.");
2631       FLAG_SET_CMDLINE(bool, UseISM, true);
2632     } else if (match_option(option, "-XX:-UsePermISM", &tail)) {
2633       FLAG_SET_CMDLINE(bool, UseISM, false);
2634 )
2635     } else if (match_option(option, "-XX:+DisplayVMOutputToStderr", &tail)) {
2636       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, false);
2637       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, true);
2638     } else if (match_option(option, "-XX:+DisplayVMOutputToStdout", &tail)) {
2639       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, false);
2640       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, true);
2641     } else if (match_option(option, "-XX:+ExtendedDTraceProbes", &tail)) {
2642 #ifdef SOLARIS
2643       FLAG_SET_CMDLINE(bool, ExtendedDTraceProbes, true);
2644       FLAG_SET_CMDLINE(bool, DTraceMethodProbes, true);
2645       FLAG_SET_CMDLINE(bool, DTraceAllocProbes, true);
2646       FLAG_SET_CMDLINE(bool, DTraceMonitorProbes, true);
2647 #else // ndef SOLARIS
2648       jio_fprintf(defaultStream::error_stream(),
2649                   "ExtendedDTraceProbes flag is only applicable on Solaris\n");
2650       return JNI_EINVAL;
2651 #endif // ndef SOLARIS
2652 #ifdef ASSERT
2653     } else if (match_option(option, "-XX:+FullGCALot", &tail)) {
2654       FLAG_SET_CMDLINE(bool, FullGCALot, true);
2655       // disable scavenge before parallel mark-compact
2656       FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
2657 #endif
2658     } else if (match_option(option, "-XX:CMSParPromoteBlocksToClaim=", &tail)) {
2659       julong cms_blocks_to_claim = (julong)atol(tail);
2660       FLAG_SET_CMDLINE(uintx, CMSParPromoteBlocksToClaim, cms_blocks_to_claim);
2661       jio_fprintf(defaultStream::error_stream(),
2662         "Please use -XX:OldPLABSize in place of "
2663         "-XX:CMSParPromoteBlocksToClaim in the future\n");
2664     } else if (match_option(option, "-XX:ParCMSPromoteBlocksToClaim=", &tail)) {
2665       julong cms_blocks_to_claim = (julong)atol(tail);
2666       FLAG_SET_CMDLINE(uintx, CMSParPromoteBlocksToClaim, cms_blocks_to_claim);
2667       jio_fprintf(defaultStream::error_stream(),
2668         "Please use -XX:OldPLABSize in place of "
2669         "-XX:ParCMSPromoteBlocksToClaim in the future\n");
2670     } else if (match_option(option, "-XX:ParallelGCOldGenAllocBufferSize=", &tail)) {
2671       julong old_plab_size = 0;
2672       ArgsRange errcode = parse_memory_size(tail, &old_plab_size, 1);
2673       if (errcode != arg_in_range) {
2674         jio_fprintf(defaultStream::error_stream(),
2675                     "Invalid old PLAB size: %s\n", option->optionString);
2676         describe_range_error(errcode);
2677         return JNI_EINVAL;
2678       }
2679       FLAG_SET_CMDLINE(uintx, OldPLABSize, old_plab_size);
2680       jio_fprintf(defaultStream::error_stream(),
2681                   "Please use -XX:OldPLABSize in place of "
2682                   "-XX:ParallelGCOldGenAllocBufferSize in the future\n");
2683     } else if (match_option(option, "-XX:ParallelGCToSpaceAllocBufferSize=", &tail)) {
2684       julong young_plab_size = 0;
2685       ArgsRange errcode = parse_memory_size(tail, &young_plab_size, 1);
2686       if (errcode != arg_in_range) {
2687         jio_fprintf(defaultStream::error_stream(),
2688                     "Invalid young PLAB size: %s\n", option->optionString);
2689         describe_range_error(errcode);
2690         return JNI_EINVAL;
2691       }
2692       FLAG_SET_CMDLINE(uintx, YoungPLABSize, young_plab_size);
2693       jio_fprintf(defaultStream::error_stream(),
2694                   "Please use -XX:YoungPLABSize in place of "
2695                   "-XX:ParallelGCToSpaceAllocBufferSize in the future\n");
2696     } else if (match_option(option, "-XX:CMSMarkStackSize=", &tail) ||
2697                match_option(option, "-XX:G1MarkStackSize=", &tail)) {
2698       julong stack_size = 0;
2699       ArgsRange errcode = parse_memory_size(tail, &stack_size, 1);
2700       if (errcode != arg_in_range) {
2701         jio_fprintf(defaultStream::error_stream(),
2702                     "Invalid mark stack size: %s\n", option->optionString);
2703         describe_range_error(errcode);
2704         return JNI_EINVAL;
2705       }
2706       FLAG_SET_CMDLINE(uintx, MarkStackSize, stack_size);
2707     } else if (match_option(option, "-XX:CMSMarkStackSizeMax=", &tail)) {
2708       julong max_stack_size = 0;
2709       ArgsRange errcode = parse_memory_size(tail, &max_stack_size, 1);
2710       if (errcode != arg_in_range) {
2711         jio_fprintf(defaultStream::error_stream(),
2712                     "Invalid maximum mark stack size: %s\n",
2713                     option->optionString);
2714         describe_range_error(errcode);
2715         return JNI_EINVAL;
2716       }
2717       FLAG_SET_CMDLINE(uintx, MarkStackSizeMax, max_stack_size);
2718     } else if (match_option(option, "-XX:ParallelMarkingThreads=", &tail) ||
2719                match_option(option, "-XX:ParallelCMSThreads=", &tail)) {
2720       uintx conc_threads = 0;
2721       if (!parse_uintx(tail, &conc_threads, 1)) {
2722         jio_fprintf(defaultStream::error_stream(),
2723                     "Invalid concurrent threads: %s\n", option->optionString);
2724         return JNI_EINVAL;
2725       }
2726       FLAG_SET_CMDLINE(uintx, ConcGCThreads, conc_threads);
2727     } else if (match_option(option, "-XX:", &tail)) { // -XX:xxxx
2728       // Skip -XX:Flags= since that case has already been handled
2729       if (strncmp(tail, "Flags=", strlen("Flags=")) != 0) {
2730         if (!process_argument(tail, args->ignoreUnrecognized, origin)) {
2731           return JNI_EINVAL;
2732         }
2733       }
2734     // Unknown option
2735     } else if (is_bad_option(option, args->ignoreUnrecognized)) {
2736       return JNI_ERR;
2737     }
2738   }
2739   // Change the default value for flags  which have different default values
2740   // when working with older JDKs.
2741   if (JDK_Version::current().compare_major(6) <= 0 &&
2742       FLAG_IS_DEFAULT(UseVMInterruptibleIO)) {
2743     FLAG_SET_DEFAULT(UseVMInterruptibleIO, true);
2744   }
2745 #ifdef LINUX
2746  if (JDK_Version::current().compare_major(6) <= 0 &&
2747       FLAG_IS_DEFAULT(UseLinuxPosixThreadCPUClocks)) {
2748     FLAG_SET_DEFAULT(UseLinuxPosixThreadCPUClocks, false);
2749   }
2750 #endif // LINUX
2751   return JNI_OK;
2752 }
2753 
2754 jint Arguments::finalize_vm_init_args(SysClassPath* scp_p, bool scp_assembly_required) {
2755   // This must be done after all -D arguments have been processed.
2756   scp_p->expand_endorsed();
2757 
2758   if (scp_assembly_required || scp_p->get_endorsed() != NULL) {
2759     // Assemble the bootclasspath elements into the final path.
2760     Arguments::set_sysclasspath(scp_p->combined_path());
2761   }
2762 
2763   // This must be done after all arguments have been processed.
2764   // java_compiler() true means set to "NONE" or empty.
2765   if (java_compiler() && !xdebug_mode()) {
2766     // For backwards compatibility, we switch to interpreted mode if
2767     // -Djava.compiler="NONE" or "" is specified AND "-Xdebug" was
2768     // not specified.
2769     set_mode_flags(_int);
2770   }
2771   if (CompileThreshold == 0) {
2772     set_mode_flags(_int);
2773   }
2774 
2775 #ifndef COMPILER2
2776   // Don't degrade server performance for footprint
2777   if (FLAG_IS_DEFAULT(UseLargePages) &&
2778       MaxHeapSize < LargePageHeapSizeThreshold) {
2779     // No need for large granularity pages w/small heaps.
2780     // Note that large pages are enabled/disabled for both the
2781     // Java heap and the code cache.
2782     FLAG_SET_DEFAULT(UseLargePages, false);
2783     SOLARIS_ONLY(FLAG_SET_DEFAULT(UseMPSS, false));
2784     SOLARIS_ONLY(FLAG_SET_DEFAULT(UseISM, false));
2785   }
2786 
2787   // Tiered compilation is undefined with C1.
2788   TieredCompilation = false;
2789 #else
2790   if (!FLAG_IS_DEFAULT(OptoLoopAlignment) && FLAG_IS_DEFAULT(MaxLoopPad)) {
2791     FLAG_SET_DEFAULT(MaxLoopPad, OptoLoopAlignment-1);
2792   }
2793   // Temporary disable bulk zeroing reduction with G1. See CR 6627983.
2794   if (UseG1GC) {
2795     FLAG_SET_DEFAULT(ReduceBulkZeroing, false);
2796   }
2797 #endif
2798 
2799   // If we are running in a headless jre, force java.awt.headless property
2800   // to be true unless the property has already been set.
2801   // Also allow the OS environment variable JAVA_AWT_HEADLESS to set headless state.
2802   if (os::is_headless_jre()) {
2803     const char* headless = Arguments::get_property("java.awt.headless");
2804     if (headless == NULL) {
2805       char envbuffer[128];
2806       if (!os::getenv("JAVA_AWT_HEADLESS", envbuffer, sizeof(envbuffer))) {
2807         if (!add_property("java.awt.headless=true")) {
2808           return JNI_ENOMEM;
2809         }
2810       } else {
2811         char buffer[256];
2812         strcpy(buffer, "java.awt.headless=");
2813         strcat(buffer, envbuffer);
2814         if (!add_property(buffer)) {
2815           return JNI_ENOMEM;
2816         }
2817       }
2818     }
2819   }
2820 
2821   if (!check_vm_args_consistency()) {
2822     return JNI_ERR;
2823   }
2824 
2825   return JNI_OK;
2826 }
2827 
2828 jint Arguments::parse_java_options_environment_variable(SysClassPath* scp_p, bool* scp_assembly_required_p) {
2829   return parse_options_environment_variable("_JAVA_OPTIONS", scp_p,
2830                                             scp_assembly_required_p);
2831 }
2832 
2833 jint Arguments::parse_java_tool_options_environment_variable(SysClassPath* scp_p, bool* scp_assembly_required_p) {
2834   return parse_options_environment_variable("JAVA_TOOL_OPTIONS", scp_p,
2835                                             scp_assembly_required_p);
2836 }
2837 
2838 jint Arguments::parse_options_environment_variable(const char* name, SysClassPath* scp_p, bool* scp_assembly_required_p) {
2839   const int N_MAX_OPTIONS = 64;
2840   const int OPTION_BUFFER_SIZE = 1024;
2841   char buffer[OPTION_BUFFER_SIZE];
2842 
2843   // The variable will be ignored if it exceeds the length of the buffer.
2844   // Don't check this variable if user has special privileges
2845   // (e.g. unix su command).
2846   if (os::getenv(name, buffer, sizeof(buffer)) &&
2847       !os::have_special_privileges()) {
2848     JavaVMOption options[N_MAX_OPTIONS];      // Construct option array
2849     jio_fprintf(defaultStream::error_stream(),
2850                 "Picked up %s: %s\n", name, buffer);
2851     char* rd = buffer;                        // pointer to the input string (rd)
2852     int i;
2853     for (i = 0; i < N_MAX_OPTIONS;) {         // repeat for all options in the input string
2854       while (isspace(*rd)) rd++;              // skip whitespace
2855       if (*rd == 0) break;                    // we re done when the input string is read completely
2856 
2857       // The output, option string, overwrites the input string.
2858       // Because of quoting, the pointer to the option string (wrt) may lag the pointer to
2859       // input string (rd).
2860       char* wrt = rd;
2861 
2862       options[i++].optionString = wrt;        // Fill in option
2863       while (*rd != 0 && !isspace(*rd)) {     // unquoted strings terminate with a space or NULL
2864         if (*rd == '\'' || *rd == '"') {      // handle a quoted string
2865           int quote = *rd;                    // matching quote to look for
2866           rd++;                               // don't copy open quote
2867           while (*rd != quote) {              // include everything (even spaces) up until quote
2868             if (*rd == 0) {                   // string termination means unmatched string
2869               jio_fprintf(defaultStream::error_stream(),
2870                           "Unmatched quote in %s\n", name);
2871               return JNI_ERR;
2872             }
2873             *wrt++ = *rd++;                   // copy to option string
2874           }
2875           rd++;                               // don't copy close quote
2876         } else {
2877           *wrt++ = *rd++;                     // copy to option string
2878         }
2879       }
2880       // Need to check if we're done before writing a NULL,
2881       // because the write could be to the byte that rd is pointing to.
2882       if (*rd++ == 0) {
2883         *wrt = 0;
2884         break;
2885       }
2886       *wrt = 0;                               // Zero terminate option
2887     }
2888     // Construct JavaVMInitArgs structure and parse as if it was part of the command line
2889     JavaVMInitArgs vm_args;
2890     vm_args.version = JNI_VERSION_1_2;
2891     vm_args.options = options;
2892     vm_args.nOptions = i;
2893     vm_args.ignoreUnrecognized = IgnoreUnrecognizedVMOptions;
2894 
2895     if (PrintVMOptions) {
2896       const char* tail;
2897       for (int i = 0; i < vm_args.nOptions; i++) {
2898         const JavaVMOption *option = vm_args.options + i;
2899         if (match_option(option, "-XX:", &tail)) {
2900           logOption(tail);
2901         }
2902       }
2903     }
2904 
2905     return(parse_each_vm_init_arg(&vm_args, scp_p, scp_assembly_required_p, ENVIRON_VAR));
2906   }
2907   return JNI_OK;
2908 }
2909 
2910 
2911 // Parse entry point called from JNI_CreateJavaVM
2912 
2913 jint Arguments::parse(const JavaVMInitArgs* args) {
2914 
2915   // Sharing support
2916   // Construct the path to the archive
2917   char jvm_path[JVM_MAXPATHLEN];
2918   os::jvm_path(jvm_path, sizeof(jvm_path));
2919 #ifdef TIERED
2920   if (strstr(jvm_path, "client") != NULL) {
2921     force_client_mode = true;
2922   }
2923 #endif // TIERED
2924   char *end = strrchr(jvm_path, *os::file_separator());
2925   if (end != NULL) *end = '\0';
2926   char *shared_archive_path = NEW_C_HEAP_ARRAY(char, strlen(jvm_path) +
2927                                         strlen(os::file_separator()) + 20);
2928   if (shared_archive_path == NULL) return JNI_ENOMEM;
2929   strcpy(shared_archive_path, jvm_path);
2930   strcat(shared_archive_path, os::file_separator());
2931   strcat(shared_archive_path, "classes");
2932   DEBUG_ONLY(strcat(shared_archive_path, "_g");)
2933   strcat(shared_archive_path, ".jsa");
2934   SharedArchivePath = shared_archive_path;
2935 
2936   // Remaining part of option string
2937   const char* tail;
2938 
2939   // If flag "-XX:Flags=flags-file" is used it will be the first option to be processed.
2940   bool settings_file_specified = false;
2941   const char* flags_file;
2942   int index;
2943   for (index = 0; index < args->nOptions; index++) {
2944     const JavaVMOption *option = args->options + index;
2945     if (match_option(option, "-XX:Flags=", &tail)) {
2946       flags_file = tail;
2947       settings_file_specified = true;
2948     }
2949     if (match_option(option, "-XX:+PrintVMOptions", &tail)) {
2950       PrintVMOptions = true;
2951     }
2952     if (match_option(option, "-XX:-PrintVMOptions", &tail)) {
2953       PrintVMOptions = false;
2954     }
2955     if (match_option(option, "-XX:+IgnoreUnrecognizedVMOptions", &tail)) {
2956       IgnoreUnrecognizedVMOptions = true;
2957     }
2958     if (match_option(option, "-XX:-IgnoreUnrecognizedVMOptions", &tail)) {
2959       IgnoreUnrecognizedVMOptions = false;
2960     }
2961     if (match_option(option, "-XX:+PrintFlagsInitial", &tail)) {
2962       CommandLineFlags::printFlags();
2963       vm_exit(0);
2964     }
2965 
2966 #ifndef PRODUCT
2967     if (match_option(option, "-XX:+PrintFlagsWithComments", &tail)) {
2968       CommandLineFlags::printFlags(true);
2969       vm_exit(0);
2970     }
2971 #endif
2972   }
2973 
2974   if (IgnoreUnrecognizedVMOptions) {
2975     // uncast const to modify the flag args->ignoreUnrecognized
2976     *(jboolean*)(&args->ignoreUnrecognized) = true;
2977   }
2978 
2979   // Parse specified settings file
2980   if (settings_file_specified) {
2981     if (!process_settings_file(flags_file, true, args->ignoreUnrecognized)) {
2982       return JNI_EINVAL;
2983     }
2984   }
2985 
2986   // Parse default .hotspotrc settings file
2987   if (!settings_file_specified) {
2988     if (!process_settings_file(".hotspotrc", false, args->ignoreUnrecognized)) {
2989       return JNI_EINVAL;
2990     }
2991   }
2992 
2993   if (PrintVMOptions) {
2994     for (index = 0; index < args->nOptions; index++) {
2995       const JavaVMOption *option = args->options + index;
2996       if (match_option(option, "-XX:", &tail)) {
2997         logOption(tail);
2998       }
2999     }
3000   }
3001 
3002   // Parse JavaVMInitArgs structure passed in, as well as JAVA_TOOL_OPTIONS and _JAVA_OPTIONS
3003   jint result = parse_vm_init_args(args);
3004   if (result != JNI_OK) {
3005     return result;
3006   }
3007 
3008 #ifndef PRODUCT
3009   if (TraceBytecodesAt != 0) {
3010     TraceBytecodes = true;
3011   }
3012   if (CountCompiledCalls) {
3013     if (UseCounterDecay) {
3014       warning("UseCounterDecay disabled because CountCalls is set");
3015       UseCounterDecay = false;
3016     }
3017   }
3018 #endif // PRODUCT
3019 
3020   if (EnableInvokeDynamic && !EnableMethodHandles) {
3021     if (!FLAG_IS_DEFAULT(EnableMethodHandles)) {
3022       warning("forcing EnableMethodHandles true because EnableInvokeDynamic is true");
3023     }
3024     EnableMethodHandles = true;
3025   }
3026   if (EnableMethodHandles && !AnonymousClasses) {
3027     if (!FLAG_IS_DEFAULT(AnonymousClasses)) {
3028       warning("forcing AnonymousClasses true because EnableMethodHandles is true");
3029     }
3030     AnonymousClasses = true;
3031   }
3032   if ((EnableMethodHandles || AnonymousClasses) && ScavengeRootsInCode == 0) {
3033     if (!FLAG_IS_DEFAULT(ScavengeRootsInCode)) {
3034       warning("forcing ScavengeRootsInCode non-zero because EnableMethodHandles or AnonymousClasses is true");
3035     }
3036     ScavengeRootsInCode = 1;
3037   }
3038 
3039   if (PrintGCDetails) {
3040     // Turn on -verbose:gc options as well
3041     PrintGC = true;
3042   }
3043 
3044   // Set object alignment values.
3045   set_object_alignment();
3046 
3047 #ifdef SERIALGC
3048   force_serial_gc();
3049 #endif // SERIALGC
3050 #ifdef KERNEL
3051   no_shared_spaces();
3052 #endif // KERNEL
3053 
3054   // Set flags based on ergonomics.
3055   set_ergonomics_flags();
3056 
3057   if (UseCompressedOops) {
3058     check_compressed_oops_compat();
3059   }
3060 
3061   // Check the GC selections again.
3062   if (!check_gc_consistency()) {
3063     return JNI_EINVAL;
3064   }
3065 
3066   if (TieredCompilation) {
3067     set_tiered_flags();
3068   } else {
3069     // Check if the policy is valid. Policies 0 and 1 are valid for non-tiered setup.
3070     if (CompilationPolicyChoice >= 2) {
3071       vm_exit_during_initialization(
3072         "Incompatible compilation policy selected", NULL);
3073     }
3074   }
3075 
3076 #ifndef KERNEL
3077   if (UseConcMarkSweepGC) {
3078     // Set flags for CMS and ParNew.  Check UseConcMarkSweep first
3079     // to ensure that when both UseConcMarkSweepGC and UseParNewGC
3080     // are true, we don't call set_parnew_gc_flags() as well.
3081     set_cms_and_parnew_gc_flags();
3082   } else {
3083     // Set heap size based on available physical memory
3084     set_heap_size();
3085     // Set per-collector flags
3086     if (UseParallelGC || UseParallelOldGC) {
3087       set_parallel_gc_flags();
3088     } else if (UseParNewGC) {
3089       set_parnew_gc_flags();
3090     } else if (UseG1GC) {
3091       set_g1_gc_flags();
3092     }
3093   }
3094 #endif // KERNEL
3095 
3096 #ifdef SERIALGC
3097   assert(verify_serial_gc_flags(), "SerialGC unset");
3098 #endif // SERIALGC
3099 
3100   // Set bytecode rewriting flags
3101   set_bytecode_flags();
3102 
3103   // Set flags if Aggressive optimization flags (-XX:+AggressiveOpts) enabled.
3104   set_aggressive_opts_flags();
3105 
3106 #ifdef CC_INTERP
3107   // Clear flags not supported by the C++ interpreter
3108   FLAG_SET_DEFAULT(ProfileInterpreter, false);
3109   FLAG_SET_DEFAULT(UseBiasedLocking, false);
3110   LP64_ONLY(FLAG_SET_DEFAULT(UseCompressedOops, false));
3111 #endif // CC_INTERP
3112 
3113 #ifdef COMPILER2
3114   if (!UseBiasedLocking || EmitSync != 0) {
3115     UseOptoBiasInlining = false;
3116   }
3117 #endif
3118 
3119   if (PrintAssembly && FLAG_IS_DEFAULT(DebugNonSafepoints)) {
3120     warning("PrintAssembly is enabled; turning on DebugNonSafepoints to gain additional output");
3121     DebugNonSafepoints = true;
3122   }
3123 
3124 #ifndef PRODUCT
3125   if (CompileTheWorld) {
3126     // Force NmethodSweeper to sweep whole CodeCache each time.
3127     if (FLAG_IS_DEFAULT(NmethodSweepFraction)) {
3128       NmethodSweepFraction = 1;
3129     }
3130   }
3131 #endif
3132 
3133   if (PrintCommandLineFlags) {
3134     CommandLineFlags::printSetFlags();
3135   }
3136 
3137   // Apply CPU specific policy for the BiasedLocking
3138   if (UseBiasedLocking) {
3139     if (!VM_Version::use_biased_locking() &&
3140         !(FLAG_IS_CMDLINE(UseBiasedLocking))) {
3141       UseBiasedLocking = false;
3142     }
3143   }
3144 
3145   return JNI_OK;
3146 }
3147 
3148 int Arguments::PropertyList_count(SystemProperty* pl) {
3149   int count = 0;
3150   while(pl != NULL) {
3151     count++;
3152     pl = pl->next();
3153   }
3154   return count;
3155 }
3156 
3157 const char* Arguments::PropertyList_get_value(SystemProperty *pl, const char* key) {
3158   assert(key != NULL, "just checking");
3159   SystemProperty* prop;
3160   for (prop = pl; prop != NULL; prop = prop->next()) {
3161     if (strcmp(key, prop->key()) == 0) return prop->value();
3162   }
3163   return NULL;
3164 }
3165 
3166 const char* Arguments::PropertyList_get_key_at(SystemProperty *pl, int index) {
3167   int count = 0;
3168   const char* ret_val = NULL;
3169 
3170   while(pl != NULL) {
3171     if(count >= index) {
3172       ret_val = pl->key();
3173       break;
3174     }
3175     count++;
3176     pl = pl->next();
3177   }
3178 
3179   return ret_val;
3180 }
3181 
3182 char* Arguments::PropertyList_get_value_at(SystemProperty* pl, int index) {
3183   int count = 0;
3184   char* ret_val = NULL;
3185 
3186   while(pl != NULL) {
3187     if(count >= index) {
3188       ret_val = pl->value();
3189       break;
3190     }
3191     count++;
3192     pl = pl->next();
3193   }
3194 
3195   return ret_val;
3196 }
3197 
3198 void Arguments::PropertyList_add(SystemProperty** plist, SystemProperty *new_p) {
3199   SystemProperty* p = *plist;
3200   if (p == NULL) {
3201     *plist = new_p;
3202   } else {
3203     while (p->next() != NULL) {
3204       p = p->next();
3205     }
3206     p->set_next(new_p);
3207   }
3208 }
3209 
3210 void Arguments::PropertyList_add(SystemProperty** plist, const char* k, char* v) {
3211   if (plist == NULL)
3212     return;
3213 
3214   SystemProperty* new_p = new SystemProperty(k, v, true);
3215   PropertyList_add(plist, new_p);
3216 }
3217 
3218 // This add maintains unique property key in the list.
3219 void Arguments::PropertyList_unique_add(SystemProperty** plist, const char* k, char* v, jboolean append) {
3220   if (plist == NULL)
3221     return;
3222 
3223   // If property key exist then update with new value.
3224   SystemProperty* prop;
3225   for (prop = *plist; prop != NULL; prop = prop->next()) {
3226     if (strcmp(k, prop->key()) == 0) {
3227       if (append) {
3228         prop->append_value(v);
3229       } else {
3230         prop->set_value(v);
3231       }
3232       return;
3233     }
3234   }
3235 
3236   PropertyList_add(plist, k, v);
3237 }
3238 
3239 #ifdef KERNEL
3240 char *Arguments::get_kernel_properties() {
3241   // Find properties starting with kernel and append them to string
3242   // We need to find out how long they are first because the URL's that they
3243   // might point to could get long.
3244   int length = 0;
3245   SystemProperty* prop;
3246   for (prop = _system_properties; prop != NULL; prop = prop->next()) {
3247     if (strncmp(prop->key(), "kernel.", 7 ) == 0) {
3248       length += (strlen(prop->key()) + strlen(prop->value()) + 5);  // "-D ="
3249     }
3250   }
3251   // Add one for null terminator.
3252   char *props = AllocateHeap(length + 1, "get_kernel_properties");
3253   if (length != 0) {
3254     int pos = 0;
3255     for (prop = _system_properties; prop != NULL; prop = prop->next()) {
3256       if (strncmp(prop->key(), "kernel.", 7 ) == 0) {
3257         jio_snprintf(&props[pos], length-pos,
3258                      "-D%s=%s ", prop->key(), prop->value());
3259         pos = strlen(props);
3260       }
3261     }
3262   }
3263   // null terminate props in case of null
3264   props[length] = '\0';
3265   return props;
3266 }
3267 #endif // KERNEL
3268 
3269 // Copies src into buf, replacing "%%" with "%" and "%p" with pid
3270 // Returns true if all of the source pointed by src has been copied over to
3271 // the destination buffer pointed by buf. Otherwise, returns false.
3272 // Notes:
3273 // 1. If the length (buflen) of the destination buffer excluding the
3274 // NULL terminator character is not long enough for holding the expanded
3275 // pid characters, it also returns false instead of returning the partially
3276 // expanded one.
3277 // 2. The passed in "buflen" should be large enough to hold the null terminator.
3278 bool Arguments::copy_expand_pid(const char* src, size_t srclen,
3279                                 char* buf, size_t buflen) {
3280   const char* p = src;
3281   char* b = buf;
3282   const char* src_end = &src[srclen];
3283   char* buf_end = &buf[buflen - 1];
3284 
3285   while (p < src_end && b < buf_end) {
3286     if (*p == '%') {
3287       switch (*(++p)) {
3288       case '%':         // "%%" ==> "%"
3289         *b++ = *p++;
3290         break;
3291       case 'p':  {       //  "%p" ==> current process id
3292         // buf_end points to the character before the last character so
3293         // that we could write '\0' to the end of the buffer.
3294         size_t buf_sz = buf_end - b + 1;
3295         int ret = jio_snprintf(b, buf_sz, "%d", os::current_process_id());
3296 
3297         // if jio_snprintf fails or the buffer is not long enough to hold
3298         // the expanded pid, returns false.
3299         if (ret < 0 || ret >= (int)buf_sz) {
3300           return false;
3301         } else {
3302           b += ret;
3303           assert(*b == '\0', "fail in copy_expand_pid");
3304           if (p == src_end && b == buf_end + 1) {
3305             // reach the end of the buffer.
3306             return true;
3307           }
3308         }
3309         p++;
3310         break;
3311       }
3312       default :
3313         *b++ = '%';
3314       }
3315     } else {
3316       *b++ = *p++;
3317     }
3318   }
3319   *b = '\0';
3320   return (p == src_end); // return false if not all of the source was copied
3321 }