1 /*
   2  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/classLoader.hpp"
  27 #include "classfile/javaAssertions.hpp"
  28 #include "classfile/symbolTable.hpp"
  29 #include "compiler/compilerOracle.hpp"
  30 #include "memory/allocation.inline.hpp"
  31 #include "memory/cardTableRS.hpp"
  32 #include "memory/genCollectedHeap.hpp"
  33 #include "memory/referenceProcessor.hpp"
  34 #include "memory/universe.inline.hpp"
  35 #include "oops/oop.inline.hpp"
  36 #include "prims/jvmtiExport.hpp"
  37 #include "runtime/arguments.hpp"
  38 #include "runtime/arguments_ext.hpp"
  39 #include "runtime/globals_extension.hpp"
  40 #include "runtime/java.hpp"
  41 #include "services/management.hpp"
  42 #include "services/memTracker.hpp"
  43 #include "utilities/defaultStream.hpp"
  44 #include "utilities/macros.hpp"
  45 #include "utilities/stringUtils.hpp"
  46 #include "utilities/taskqueue.hpp"
  47 #ifdef TARGET_OS_FAMILY_linux
  48 # include "os_linux.inline.hpp"
  49 #endif
  50 #ifdef TARGET_OS_FAMILY_solaris
  51 # include "os_solaris.inline.hpp"
  52 #endif
  53 #ifdef TARGET_OS_FAMILY_windows
  54 # include "os_windows.inline.hpp"
  55 #endif
  56 #ifdef TARGET_OS_FAMILY_aix
  57 # include "os_aix.inline.hpp"
  58 #endif
  59 #ifdef TARGET_OS_FAMILY_bsd
  60 # include "os_bsd.inline.hpp"
  61 #endif
  62 #if INCLUDE_ALL_GCS
  63 #include "gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.hpp"
  64 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
  65 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
  66 #include "gc_implementation/shenandoah/shenandoahHeap.hpp"
  67 #include "gc_implementation/shenandoah/shenandoahLogging.hpp"
  68 #endif // INCLUDE_ALL_GCS
  69 
  70 // Note: This is a special bug reporting site for the JVM
  71 #define DEFAULT_VENDOR_URL_BUG "http://bugreport.java.com/bugreport/crash.jsp"
  72 #define DEFAULT_JAVA_LAUNCHER  "generic"
  73 
  74 // Disable options not supported in this release, with a warning if they
  75 // were explicitly requested on the command-line
  76 #define UNSUPPORTED_OPTION(opt, description)                    \
  77 do {                                                            \
  78   if (opt) {                                                    \
  79     if (FLAG_IS_CMDLINE(opt)) {                                 \
  80       warning(description " is disabled in this release.");     \
  81     }                                                           \
  82     FLAG_SET_DEFAULT(opt, false);                               \
  83   }                                                             \
  84 } while(0)
  85 
  86 #define UNSUPPORTED_GC_OPTION(gc)                                     \
  87 do {                                                                  \
  88   if (gc) {                                                           \
  89     if (FLAG_IS_CMDLINE(gc)) {                                        \
  90       warning(#gc " is not supported in this VM.  Using Serial GC."); \
  91     }                                                                 \
  92     FLAG_SET_DEFAULT(gc, false);                                      \
  93   }                                                                   \
  94 } while(0)
  95 
  96 char**  Arguments::_jvm_flags_array             = NULL;
  97 int     Arguments::_num_jvm_flags               = 0;
  98 char**  Arguments::_jvm_args_array              = NULL;
  99 int     Arguments::_num_jvm_args                = 0;
 100 char*  Arguments::_java_command                 = NULL;
 101 SystemProperty* Arguments::_system_properties   = NULL;
 102 const char*  Arguments::_gc_log_filename        = NULL;
 103 bool   Arguments::_has_profile                  = false;
 104 size_t Arguments::_conservative_max_heap_alignment = 0;
 105 uintx  Arguments::_min_heap_size                = 0;
 106 uintx  Arguments::_min_heap_free_ratio          = 0;
 107 uintx  Arguments::_max_heap_free_ratio          = 0;
 108 Arguments::Mode Arguments::_mode                = _mixed;
 109 bool   Arguments::_java_compiler                = false;
 110 bool   Arguments::_xdebug_mode                  = false;
 111 const char*  Arguments::_java_vendor_url_bug    = DEFAULT_VENDOR_URL_BUG;
 112 const char*  Arguments::_sun_java_launcher      = DEFAULT_JAVA_LAUNCHER;
 113 int    Arguments::_sun_java_launcher_pid        = -1;
 114 bool   Arguments::_created_by_gamma_launcher    = false;
 115 
 116 // These parameters are reset in method parse_vm_init_args(JavaVMInitArgs*)
 117 bool   Arguments::_AlwaysCompileLoopMethods     = AlwaysCompileLoopMethods;
 118 bool   Arguments::_UseOnStackReplacement        = UseOnStackReplacement;
 119 bool   Arguments::_BackgroundCompilation        = BackgroundCompilation;
 120 bool   Arguments::_ClipInlining                 = ClipInlining;
 121 
 122 char*  Arguments::SharedArchivePath             = NULL;
 123 
 124 AgentLibraryList Arguments::_libraryList;
 125 AgentLibraryList Arguments::_agentList;
 126 
 127 abort_hook_t     Arguments::_abort_hook         = NULL;
 128 exit_hook_t      Arguments::_exit_hook          = NULL;
 129 vfprintf_hook_t  Arguments::_vfprintf_hook      = NULL;
 130 
 131 
 132 SystemProperty *Arguments::_java_ext_dirs = NULL;
 133 SystemProperty *Arguments::_java_endorsed_dirs = NULL;
 134 SystemProperty *Arguments::_sun_boot_library_path = NULL;
 135 SystemProperty *Arguments::_java_library_path = NULL;
 136 SystemProperty *Arguments::_java_home = NULL;
 137 SystemProperty *Arguments::_java_class_path = NULL;
 138 SystemProperty *Arguments::_sun_boot_class_path = NULL;
 139 
 140 char* Arguments::_meta_index_path = NULL;
 141 char* Arguments::_meta_index_dir = NULL;
 142 
 143 // Check if head of 'option' matches 'name', and sets 'tail' remaining part of option string
 144 
 145 static bool match_option(const JavaVMOption *option, const char* name,
 146                          const char** tail) {
 147   int len = (int)strlen(name);
 148   if (strncmp(option->optionString, name, len) == 0) {
 149     *tail = option->optionString + len;
 150     return true;
 151   } else {
 152     return false;
 153   }
 154 }
 155 
 156 static void logOption(const char* opt) {
 157   if (PrintVMOptions) {
 158     jio_fprintf(defaultStream::output_stream(), "VM option '%s'\n", opt);
 159   }
 160 }
 161 
 162 // Process java launcher properties.
 163 void Arguments::process_sun_java_launcher_properties(JavaVMInitArgs* args) {
 164   // See if sun.java.launcher or sun.java.launcher.pid is defined.
 165   // Must do this before setting up other system properties,
 166   // as some of them may depend on launcher type.
 167   for (int index = 0; index < args->nOptions; index++) {
 168     const JavaVMOption* option = args->options + index;
 169     const char* tail;
 170 
 171     if (match_option(option, "-Dsun.java.launcher=", &tail)) {
 172       process_java_launcher_argument(tail, option->extraInfo);
 173       continue;
 174     }
 175     if (match_option(option, "-Dsun.java.launcher.pid=", &tail)) {
 176       _sun_java_launcher_pid = atoi(tail);
 177       continue;
 178     }
 179   }
 180 }
 181 
 182 // Initialize system properties key and value.
 183 void Arguments::init_system_properties() {
 184 
 185   PropertyList_add(&_system_properties, new SystemProperty("java.vm.specification.name",
 186                                                                  "Java Virtual Machine Specification",  false));
 187   PropertyList_add(&_system_properties, new SystemProperty("java.vm.version", VM_Version::vm_release(),  false));
 188   PropertyList_add(&_system_properties, new SystemProperty("java.vm.name", VM_Version::vm_name(),  false));
 189   PropertyList_add(&_system_properties, new SystemProperty("java.vm.info", VM_Version::vm_info_string(),  true));
 190 
 191   // following are JVMTI agent writeable properties.
 192   // Properties values are set to NULL and they are
 193   // os specific they are initialized in os::init_system_properties_values().
 194   _java_ext_dirs = new SystemProperty("java.ext.dirs", NULL,  true);
 195   _java_endorsed_dirs = new SystemProperty("java.endorsed.dirs", NULL,  true);
 196   _sun_boot_library_path = new SystemProperty("sun.boot.library.path", NULL,  true);
 197   _java_library_path = new SystemProperty("java.library.path", NULL,  true);
 198   _java_home =  new SystemProperty("java.home", NULL,  true);
 199   _sun_boot_class_path = new SystemProperty("sun.boot.class.path", NULL,  true);
 200 
 201   _java_class_path = new SystemProperty("java.class.path", "",  true);
 202 
 203   // Add to System Property list.
 204   PropertyList_add(&_system_properties, _java_ext_dirs);
 205   PropertyList_add(&_system_properties, _java_endorsed_dirs);
 206   PropertyList_add(&_system_properties, _sun_boot_library_path);
 207   PropertyList_add(&_system_properties, _java_library_path);
 208   PropertyList_add(&_system_properties, _java_home);
 209   PropertyList_add(&_system_properties, _java_class_path);
 210   PropertyList_add(&_system_properties, _sun_boot_class_path);
 211 
 212   // Set OS specific system properties values
 213   os::init_system_properties_values();
 214 }
 215 
 216 
 217   // Update/Initialize System properties after JDK version number is known
 218 void Arguments::init_version_specific_system_properties() {
 219   enum { bufsz = 16 };
 220   char buffer[bufsz];
 221   const char* spec_vendor = "Sun Microsystems Inc.";
 222   uint32_t spec_version = 0;
 223 
 224   if (JDK_Version::is_gte_jdk17x_version()) {
 225     spec_vendor = "Oracle Corporation";
 226     spec_version = JDK_Version::current().major_version();
 227   }
 228   jio_snprintf(buffer, bufsz, "1." UINT32_FORMAT, spec_version);
 229 
 230   PropertyList_add(&_system_properties,
 231       new SystemProperty("java.vm.specification.vendor",  spec_vendor, false));
 232   PropertyList_add(&_system_properties,
 233       new SystemProperty("java.vm.specification.version", buffer, false));
 234   PropertyList_add(&_system_properties,
 235       new SystemProperty("java.vm.vendor", VM_Version::vm_vendor(),  false));
 236 }
 237 
 238 /**
 239  * Provide a slightly more user-friendly way of eliminating -XX flags.
 240  * When a flag is eliminated, it can be added to this list in order to
 241  * continue accepting this flag on the command-line, while issuing a warning
 242  * and ignoring the value.  Once the JDK version reaches the 'accept_until'
 243  * limit, we flatly refuse to admit the existence of the flag.  This allows
 244  * a flag to die correctly over JDK releases using HSX.
 245  */
 246 typedef struct {
 247   const char* name;
 248   JDK_Version obsoleted_in; // when the flag went away
 249   JDK_Version accept_until; // which version to start denying the existence
 250 } ObsoleteFlag;
 251 
 252 static ObsoleteFlag obsolete_jvm_flags[] = {
 253   { "UseTrainGC",                    JDK_Version::jdk(5), JDK_Version::jdk(7) },
 254   { "UseSpecialLargeObjectHandling", JDK_Version::jdk(5), JDK_Version::jdk(7) },
 255   { "UseOversizedCarHandling",       JDK_Version::jdk(5), JDK_Version::jdk(7) },
 256   { "TraceCarAllocation",            JDK_Version::jdk(5), JDK_Version::jdk(7) },
 257   { "PrintTrainGCProcessingStats",   JDK_Version::jdk(5), JDK_Version::jdk(7) },
 258   { "LogOfCarSpaceSize",             JDK_Version::jdk(5), JDK_Version::jdk(7) },
 259   { "OversizedCarThreshold",         JDK_Version::jdk(5), JDK_Version::jdk(7) },
 260   { "MinTickInterval",               JDK_Version::jdk(5), JDK_Version::jdk(7) },
 261   { "DefaultTickInterval",           JDK_Version::jdk(5), JDK_Version::jdk(7) },
 262   { "MaxTickInterval",               JDK_Version::jdk(5), JDK_Version::jdk(7) },
 263   { "DelayTickAdjustment",           JDK_Version::jdk(5), JDK_Version::jdk(7) },
 264   { "ProcessingToTenuringRatio",     JDK_Version::jdk(5), JDK_Version::jdk(7) },
 265   { "MinTrainLength",                JDK_Version::jdk(5), JDK_Version::jdk(7) },
 266   { "AppendRatio",         JDK_Version::jdk_update(6,10), JDK_Version::jdk(7) },
 267   { "DefaultMaxRAM",       JDK_Version::jdk_update(6,18), JDK_Version::jdk(7) },
 268   { "DefaultInitialRAMFraction",
 269                            JDK_Version::jdk_update(6,18), JDK_Version::jdk(7) },
 270   { "UseDepthFirstScavengeOrder",
 271                            JDK_Version::jdk_update(6,22), JDK_Version::jdk(7) },
 272   { "HandlePromotionFailure",
 273                            JDK_Version::jdk_update(6,24), JDK_Version::jdk(8) },
 274   { "MaxLiveObjectEvacuationRatio",
 275                            JDK_Version::jdk_update(6,24), JDK_Version::jdk(8) },
 276   { "ForceSharedSpaces",   JDK_Version::jdk_update(6,25), JDK_Version::jdk(8) },
 277   { "UseParallelOldGCCompacting",
 278                            JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
 279   { "UseParallelDensePrefixUpdate",
 280                            JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
 281   { "UseParallelOldGCDensePrefix",
 282                            JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
 283   { "AllowTransitionalJSR292",       JDK_Version::jdk(7), JDK_Version::jdk(8) },
 284   { "UseCompressedStrings",          JDK_Version::jdk(7), JDK_Version::jdk(8) },
 285   { "CMSPermGenPrecleaningEnabled", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 286   { "CMSTriggerPermRatio", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 287   { "CMSInitiatingPermOccupancyFraction", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 288   { "AdaptivePermSizeWeight", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 289   { "PermGenPadding", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 290   { "PermMarkSweepDeadRatio", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 291   { "PermSize", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 292   { "MaxPermSize", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 293   { "MinPermHeapExpansion", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 294   { "MaxPermHeapExpansion", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
 295   { "CMSRevisitStackSize",           JDK_Version::jdk(8), JDK_Version::jdk(9) },
 296   { "PrintRevisitStats",             JDK_Version::jdk(8), JDK_Version::jdk(9) },
 297   { "UseVectoredExceptions",         JDK_Version::jdk(8), JDK_Version::jdk(9) },
 298   { "UseSplitVerifier",              JDK_Version::jdk(8), JDK_Version::jdk(9) },
 299   { "UseISM",                        JDK_Version::jdk(8), JDK_Version::jdk(9) },
 300   { "UsePermISM",                    JDK_Version::jdk(8), JDK_Version::jdk(9) },
 301   { "UseMPSS",                       JDK_Version::jdk(8), JDK_Version::jdk(9) },
 302   { "UseStringCache",                JDK_Version::jdk(8), JDK_Version::jdk(9) },
 303   { "UseOldInlining",                JDK_Version::jdk(9), JDK_Version::jdk(10) },
 304   { "AutoShutdownNMT",               JDK_Version::jdk(9), JDK_Version::jdk(10) },
 305   { "CompilationRepeat",             JDK_Version::jdk(8), JDK_Version::jdk(9) },
 306 #ifdef PRODUCT
 307   { "DesiredMethodLimit",
 308                            JDK_Version::jdk_update(7, 2), JDK_Version::jdk(8) },
 309 #endif // PRODUCT
 310   { NULL, JDK_Version(0), JDK_Version(0) }
 311 };
 312 
 313 // Returns true if the flag is obsolete and fits into the range specified
 314 // for being ignored.  In the case that the flag is ignored, the 'version'
 315 // value is filled in with the version number when the flag became
 316 // obsolete so that that value can be displayed to the user.
 317 bool Arguments::is_newly_obsolete(const char *s, JDK_Version* version) {
 318   int i = 0;
 319   assert(version != NULL, "Must provide a version buffer");
 320   while (obsolete_jvm_flags[i].name != NULL) {
 321     const ObsoleteFlag& flag_status = obsolete_jvm_flags[i];
 322     // <flag>=xxx form
 323     // [-|+]<flag> form
 324     if ((strncmp(flag_status.name, s, strlen(flag_status.name)) == 0) ||
 325         ((s[0] == '+' || s[0] == '-') &&
 326         (strncmp(flag_status.name, &s[1], strlen(flag_status.name)) == 0))) {
 327       if (JDK_Version::current().compare(flag_status.accept_until) == -1) {
 328           *version = flag_status.obsoleted_in;
 329           return true;
 330       }
 331     }
 332     i++;
 333   }
 334   return false;
 335 }
 336 
 337 // Constructs the system class path (aka boot class path) from the following
 338 // components, in order:
 339 //
 340 //     prefix           // from -Xbootclasspath/p:...
 341 //     endorsed         // the expansion of -Djava.endorsed.dirs=...
 342 //     base             // from os::get_system_properties() or -Xbootclasspath=
 343 //     suffix           // from -Xbootclasspath/a:...
 344 //
 345 // java.endorsed.dirs is a list of directories; any jar or zip files in the
 346 // directories are added to the sysclasspath just before the base.
 347 //
 348 // This could be AllStatic, but it isn't needed after argument processing is
 349 // complete.
 350 class SysClassPath: public StackObj {
 351 public:
 352   SysClassPath(const char* base);
 353   ~SysClassPath();
 354 
 355   inline void set_base(const char* base);
 356   inline void add_prefix(const char* prefix);
 357   inline void add_suffix_to_prefix(const char* suffix);
 358   inline void add_suffix(const char* suffix);
 359   inline void reset_path(const char* base);
 360 
 361   // Expand the jar/zip files in each directory listed by the java.endorsed.dirs
 362   // property.  Must be called after all command-line arguments have been
 363   // processed (in particular, -Djava.endorsed.dirs=...) and before calling
 364   // combined_path().
 365   void expand_endorsed();
 366 
 367   inline const char* get_base()     const { return _items[_scp_base]; }
 368   inline const char* get_prefix()   const { return _items[_scp_prefix]; }
 369   inline const char* get_suffix()   const { return _items[_scp_suffix]; }
 370   inline const char* get_endorsed() const { return _items[_scp_endorsed]; }
 371 
 372   // Combine all the components into a single c-heap-allocated string; caller
 373   // must free the string if/when no longer needed.
 374   char* combined_path();
 375 
 376 private:
 377   // Utility routines.
 378   static char* add_to_path(const char* path, const char* str, bool prepend);
 379   static char* add_jars_to_path(char* path, const char* directory);
 380 
 381   inline void reset_item_at(int index);
 382 
 383   // Array indices for the items that make up the sysclasspath.  All except the
 384   // base are allocated in the C heap and freed by this class.
 385   enum {
 386     _scp_prefix,        // from -Xbootclasspath/p:...
 387     _scp_endorsed,      // the expansion of -Djava.endorsed.dirs=...
 388     _scp_base,          // the default sysclasspath
 389     _scp_suffix,        // from -Xbootclasspath/a:...
 390     _scp_nitems         // the number of items, must be last.
 391   };
 392 
 393   const char* _items[_scp_nitems];
 394   DEBUG_ONLY(bool _expansion_done;)
 395 };
 396 
 397 SysClassPath::SysClassPath(const char* base) {
 398   memset(_items, 0, sizeof(_items));
 399   _items[_scp_base] = base;
 400   DEBUG_ONLY(_expansion_done = false;)
 401 }
 402 
 403 SysClassPath::~SysClassPath() {
 404   // Free everything except the base.
 405   for (int i = 0; i < _scp_nitems; ++i) {
 406     if (i != _scp_base) reset_item_at(i);
 407   }
 408   DEBUG_ONLY(_expansion_done = false;)
 409 }
 410 
 411 inline void SysClassPath::set_base(const char* base) {
 412   _items[_scp_base] = base;
 413 }
 414 
 415 inline void SysClassPath::add_prefix(const char* prefix) {
 416   _items[_scp_prefix] = add_to_path(_items[_scp_prefix], prefix, true);
 417 }
 418 
 419 inline void SysClassPath::add_suffix_to_prefix(const char* suffix) {
 420   _items[_scp_prefix] = add_to_path(_items[_scp_prefix], suffix, false);
 421 }
 422 
 423 inline void SysClassPath::add_suffix(const char* suffix) {
 424   _items[_scp_suffix] = add_to_path(_items[_scp_suffix], suffix, false);
 425 }
 426 
 427 inline void SysClassPath::reset_item_at(int index) {
 428   assert(index < _scp_nitems && index != _scp_base, "just checking");
 429   if (_items[index] != NULL) {
 430     FREE_C_HEAP_ARRAY(char, _items[index], mtInternal);
 431     _items[index] = NULL;
 432   }
 433 }
 434 
 435 inline void SysClassPath::reset_path(const char* base) {
 436   // Clear the prefix and suffix.
 437   reset_item_at(_scp_prefix);
 438   reset_item_at(_scp_suffix);
 439   set_base(base);
 440 }
 441 
 442 //------------------------------------------------------------------------------
 443 
 444 void SysClassPath::expand_endorsed() {
 445   assert(_items[_scp_endorsed] == NULL, "can only be called once.");
 446 
 447   const char* path = Arguments::get_property("java.endorsed.dirs");
 448   if (path == NULL) {
 449     path = Arguments::get_endorsed_dir();
 450     assert(path != NULL, "no default for java.endorsed.dirs");
 451   }
 452 
 453   char* expanded_path = NULL;
 454   const char separator = *os::path_separator();
 455   const char* const end = path + strlen(path);
 456   while (path < end) {
 457     const char* tmp_end = strchr(path, separator);
 458     if (tmp_end == NULL) {
 459       expanded_path = add_jars_to_path(expanded_path, path);
 460       path = end;
 461     } else {
 462       char* dirpath = NEW_C_HEAP_ARRAY(char, tmp_end - path + 1, mtInternal);
 463       memcpy(dirpath, path, tmp_end - path);
 464       dirpath[tmp_end - path] = '\0';
 465       expanded_path = add_jars_to_path(expanded_path, dirpath);
 466       FREE_C_HEAP_ARRAY(char, dirpath, mtInternal);
 467       path = tmp_end + 1;
 468     }
 469   }
 470   _items[_scp_endorsed] = expanded_path;
 471   DEBUG_ONLY(_expansion_done = true;)
 472 }
 473 
 474 // Combine the bootclasspath elements, some of which may be null, into a single
 475 // c-heap-allocated string.
 476 char* SysClassPath::combined_path() {
 477   assert(_items[_scp_base] != NULL, "empty default sysclasspath");
 478   assert(_expansion_done, "must call expand_endorsed() first.");
 479 
 480   size_t lengths[_scp_nitems];
 481   size_t total_len = 0;
 482 
 483   const char separator = *os::path_separator();
 484 
 485   // Get the lengths.
 486   int i;
 487   for (i = 0; i < _scp_nitems; ++i) {
 488     if (_items[i] != NULL) {
 489       lengths[i] = strlen(_items[i]);
 490       // Include space for the separator char (or a NULL for the last item).
 491       total_len += lengths[i] + 1;
 492     }
 493   }
 494   assert(total_len > 0, "empty sysclasspath not allowed");
 495 
 496   // Copy the _items to a single string.
 497   char* cp = NEW_C_HEAP_ARRAY(char, total_len, mtInternal);
 498   char* cp_tmp = cp;
 499   for (i = 0; i < _scp_nitems; ++i) {
 500     if (_items[i] != NULL) {
 501       memcpy(cp_tmp, _items[i], lengths[i]);
 502       cp_tmp += lengths[i];
 503       *cp_tmp++ = separator;
 504     }
 505   }
 506   *--cp_tmp = '\0';     // Replace the extra separator.
 507   return cp;
 508 }
 509 
 510 // Note:  path must be c-heap-allocated (or NULL); it is freed if non-null.
 511 char*
 512 SysClassPath::add_to_path(const char* path, const char* str, bool prepend) {
 513   char *cp;
 514 
 515   assert(str != NULL, "just checking");
 516   if (path == NULL) {
 517     size_t len = strlen(str) + 1;
 518     cp = NEW_C_HEAP_ARRAY(char, len, mtInternal);
 519     memcpy(cp, str, len);                       // copy the trailing null
 520   } else {
 521     const char separator = *os::path_separator();
 522     size_t old_len = strlen(path);
 523     size_t str_len = strlen(str);
 524     size_t len = old_len + str_len + 2;
 525 
 526     if (prepend) {
 527       cp = NEW_C_HEAP_ARRAY(char, len, mtInternal);
 528       char* cp_tmp = cp;
 529       memcpy(cp_tmp, str, str_len);
 530       cp_tmp += str_len;
 531       *cp_tmp = separator;
 532       memcpy(++cp_tmp, path, old_len + 1);      // copy the trailing null
 533       FREE_C_HEAP_ARRAY(char, path, mtInternal);
 534     } else {
 535       cp = REALLOC_C_HEAP_ARRAY(char, path, len, mtInternal);
 536       char* cp_tmp = cp + old_len;
 537       *cp_tmp = separator;
 538       memcpy(++cp_tmp, str, str_len + 1);       // copy the trailing null
 539     }
 540   }
 541   return cp;
 542 }
 543 
 544 // Scan the directory and append any jar or zip files found to path.
 545 // Note:  path must be c-heap-allocated (or NULL); it is freed if non-null.
 546 char* SysClassPath::add_jars_to_path(char* path, const char* directory) {
 547   DIR* dir = os::opendir(directory);
 548   if (dir == NULL) return path;
 549 
 550   char dir_sep[2] = { '\0', '\0' };
 551   size_t directory_len = strlen(directory);
 552   const char fileSep = *os::file_separator();
 553   if (directory[directory_len - 1] != fileSep) dir_sep[0] = fileSep;
 554 
 555   /* Scan the directory for jars/zips, appending them to path. */
 556   struct dirent *entry;
 557   char *dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory), mtInternal);
 558   while ((entry = os::readdir(dir, (dirent *) dbuf)) != NULL) {
 559     const char* name = entry->d_name;
 560     const char* ext = name + strlen(name) - 4;
 561     bool isJarOrZip = ext > name &&
 562       (os::file_name_strcmp(ext, ".jar") == 0 ||
 563        os::file_name_strcmp(ext, ".zip") == 0);
 564     if (isJarOrZip) {
 565       size_t length = directory_len + 2 + strlen(name);
 566       char* jarpath = NEW_C_HEAP_ARRAY(char, length, mtInternal);
 567       jio_snprintf(jarpath, length, "%s%s%s", directory, dir_sep, name);
 568       path = add_to_path(path, jarpath, false);
 569       FREE_C_HEAP_ARRAY(char, jarpath, mtInternal);
 570     }
 571   }
 572   FREE_C_HEAP_ARRAY(char, dbuf, mtInternal);
 573   os::closedir(dir);
 574   return path;
 575 }
 576 
 577 // Parses a memory size specification string.
 578 static bool atomull(const char *s, julong* result) {
 579   julong n = 0;
 580   int args_read = sscanf(s, JULONG_FORMAT, &n);
 581   if (args_read != 1) {
 582     return false;
 583   }
 584   while (*s != '\0' && isdigit(*s)) {
 585     s++;
 586   }
 587   // 4705540: illegal if more characters are found after the first non-digit
 588   if (strlen(s) > 1) {
 589     return false;
 590   }
 591   switch (*s) {
 592     case 'T': case 't':
 593       *result = n * G * K;
 594       // Check for overflow.
 595       if (*result/((julong)G * K) != n) return false;
 596       return true;
 597     case 'G': case 'g':
 598       *result = n * G;
 599       if (*result/G != n) return false;
 600       return true;
 601     case 'M': case 'm':
 602       *result = n * M;
 603       if (*result/M != n) return false;
 604       return true;
 605     case 'K': case 'k':
 606       *result = n * K;
 607       if (*result/K != n) return false;
 608       return true;
 609     case '\0':
 610       *result = n;
 611       return true;
 612     default:
 613       return false;
 614   }
 615 }
 616 
 617 Arguments::ArgsRange Arguments::check_memory_size(julong size, julong min_size) {
 618   if (size < min_size) return arg_too_small;
 619   // Check that size will fit in a size_t (only relevant on 32-bit)
 620   if (size > max_uintx) return arg_too_big;
 621   return arg_in_range;
 622 }
 623 
 624 // Describe an argument out of range error
 625 void Arguments::describe_range_error(ArgsRange errcode) {
 626   switch(errcode) {
 627   case arg_too_big:
 628     jio_fprintf(defaultStream::error_stream(),
 629                 "The specified size exceeds the maximum "
 630                 "representable size.\n");
 631     break;
 632   case arg_too_small:
 633   case arg_unreadable:
 634   case arg_in_range:
 635     // do nothing for now
 636     break;
 637   default:
 638     ShouldNotReachHere();
 639   }
 640 }
 641 
 642 static bool set_bool_flag(char* name, bool value, Flag::Flags origin) {
 643   return CommandLineFlags::boolAtPut(name, &value, origin);
 644 }
 645 
 646 static bool set_fp_numeric_flag(char* name, char* value, Flag::Flags origin) {
 647   double v;
 648   if (sscanf(value, "%lf", &v) != 1) {
 649     return false;
 650   }
 651 
 652   if (CommandLineFlags::doubleAtPut(name, &v, origin)) {
 653     return true;
 654   }
 655   return false;
 656 }
 657 
 658 static bool set_numeric_flag(char* name, char* value, Flag::Flags origin) {
 659   julong v;
 660   intx intx_v;
 661   bool is_neg = false;
 662   // Check the sign first since atomull() parses only unsigned values.
 663   if (*value == '-') {
 664     if (!CommandLineFlags::intxAt(name, &intx_v)) {
 665       return false;
 666     }
 667     value++;
 668     is_neg = true;
 669   }
 670   if (!atomull(value, &v)) {
 671     return false;
 672   }
 673   intx_v = (intx) v;
 674   if (is_neg) {
 675     intx_v = -intx_v;
 676   }
 677   if (CommandLineFlags::intxAtPut(name, &intx_v, origin)) {
 678     return true;
 679   }
 680   uintx uintx_v = (uintx) v;
 681   if (!is_neg && CommandLineFlags::uintxAtPut(name, &uintx_v, origin)) {
 682     return true;
 683   }
 684   uint64_t uint64_t_v = (uint64_t) v;
 685   if (!is_neg && CommandLineFlags::uint64_tAtPut(name, &uint64_t_v, origin)) {
 686     return true;
 687   }
 688   return false;
 689 }
 690 
 691 static bool set_string_flag(char* name, const char* value, Flag::Flags origin) {
 692   if (!CommandLineFlags::ccstrAtPut(name, &value, origin))  return false;
 693   // Contract:  CommandLineFlags always returns a pointer that needs freeing.
 694   FREE_C_HEAP_ARRAY(char, value, mtInternal);
 695   return true;
 696 }
 697 
 698 static bool append_to_string_flag(char* name, const char* new_value, Flag::Flags origin) {
 699   const char* old_value = "";
 700   if (!CommandLineFlags::ccstrAt(name, &old_value))  return false;
 701   size_t old_len = old_value != NULL ? strlen(old_value) : 0;
 702   size_t new_len = strlen(new_value);
 703   const char* value;
 704   char* free_this_too = NULL;
 705   if (old_len == 0) {
 706     value = new_value;
 707   } else if (new_len == 0) {
 708     value = old_value;
 709   } else {
 710     size_t length = old_len + 1 + new_len + 1;
 711     char* buf = NEW_C_HEAP_ARRAY(char, length, mtInternal);
 712     // each new setting adds another LINE to the switch:
 713     jio_snprintf(buf, length, "%s\n%s", old_value, new_value);
 714     value = buf;
 715     free_this_too = buf;
 716   }
 717   (void) CommandLineFlags::ccstrAtPut(name, &value, origin);
 718   // CommandLineFlags always returns a pointer that needs freeing.
 719   FREE_C_HEAP_ARRAY(char, value, mtInternal);
 720   if (free_this_too != NULL) {
 721     // CommandLineFlags made its own copy, so I must delete my own temp. buffer.
 722     FREE_C_HEAP_ARRAY(char, free_this_too, mtInternal);
 723   }
 724   return true;
 725 }
 726 
 727 bool Arguments::parse_argument(const char* arg, Flag::Flags origin) {
 728 
 729   // range of acceptable characters spelled out for portability reasons
 730 #define NAME_RANGE  "[abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_]"
 731 #define BUFLEN 255
 732   char name[BUFLEN+1];
 733   char dummy;
 734 
 735   if (sscanf(arg, "-%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
 736     return set_bool_flag(name, false, origin);
 737   }
 738   if (sscanf(arg, "+%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
 739     return set_bool_flag(name, true, origin);
 740   }
 741 
 742   char punct;
 743   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "%c", name, &punct) == 2 && punct == '=') {
 744     const char* value = strchr(arg, '=') + 1;
 745     Flag* flag = Flag::find_flag(name, strlen(name));
 746     if (flag != NULL && flag->is_ccstr()) {
 747       if (flag->ccstr_accumulates()) {
 748         return append_to_string_flag(name, value, origin);
 749       } else {
 750         if (value[0] == '\0') {
 751           value = NULL;
 752         }
 753         return set_string_flag(name, value, origin);
 754       }
 755     }
 756   }
 757 
 758   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE ":%c", name, &punct) == 2 && punct == '=') {
 759     const char* value = strchr(arg, '=') + 1;
 760     // -XX:Foo:=xxx will reset the string flag to the given value.
 761     if (value[0] == '\0') {
 762       value = NULL;
 763     }
 764     return set_string_flag(name, value, origin);
 765   }
 766 
 767 #define SIGNED_FP_NUMBER_RANGE "[-0123456789.]"
 768 #define SIGNED_NUMBER_RANGE    "[-0123456789]"
 769 #define        NUMBER_RANGE    "[0123456789]"
 770   char value[BUFLEN + 1];
 771   char value2[BUFLEN + 1];
 772   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_NUMBER_RANGE "." "%" XSTR(BUFLEN) NUMBER_RANGE "%c", name, value, value2, &dummy) == 3) {
 773     // Looks like a floating-point number -- try again with more lenient format string
 774     if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_FP_NUMBER_RANGE "%c", name, value, &dummy) == 2) {
 775       return set_fp_numeric_flag(name, value, origin);
 776     }
 777   }
 778 
 779 #define VALUE_RANGE "[-kmgtKMGT0123456789]"
 780   if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) VALUE_RANGE "%c", name, value, &dummy) == 2) {
 781     return set_numeric_flag(name, value, origin);
 782   }
 783 
 784   return false;
 785 }
 786 
 787 void Arguments::add_string(char*** bldarray, int* count, const char* arg) {
 788   assert(bldarray != NULL, "illegal argument");
 789 
 790   if (arg == NULL) {
 791     return;
 792   }
 793 
 794   int new_count = *count + 1;
 795 
 796   // expand the array and add arg to the last element
 797   if (*bldarray == NULL) {
 798     *bldarray = NEW_C_HEAP_ARRAY(char*, new_count, mtInternal);
 799   } else {
 800     *bldarray = REALLOC_C_HEAP_ARRAY(char*, *bldarray, new_count, mtInternal);
 801   }
 802   (*bldarray)[*count] = strdup(arg);
 803   *count = new_count;
 804 }
 805 
 806 void Arguments::build_jvm_args(const char* arg) {
 807   add_string(&_jvm_args_array, &_num_jvm_args, arg);
 808 }
 809 
 810 void Arguments::build_jvm_flags(const char* arg) {
 811   add_string(&_jvm_flags_array, &_num_jvm_flags, arg);
 812 }
 813 
 814 // utility function to return a string that concatenates all
 815 // strings in a given char** array
 816 const char* Arguments::build_resource_string(char** args, int count) {
 817   if (args == NULL || count == 0) {
 818     return NULL;
 819   }
 820   size_t length = 0;
 821   for (int i = 0; i < count; i++) {
 822     length += strlen(args[i]) + 1; // add 1 for a space or NULL terminating character
 823   }
 824   char* s = NEW_RESOURCE_ARRAY(char, length);
 825   char* dst = s;
 826   for (int j = 0; j < count; j++) {
 827     size_t offset = strlen(args[j]) + 1; // add 1 for a space or NULL terminating character
 828     jio_snprintf(dst, length, "%s ", args[j]); // jio_snprintf will replace the last space character with NULL character
 829     dst += offset;
 830     length -= offset;
 831   }
 832   return (const char*) s;
 833 }
 834 
 835 void Arguments::print_on(outputStream* st) {
 836   st->print_cr("VM Arguments:");
 837   if (num_jvm_flags() > 0) {
 838     st->print("jvm_flags: "); print_jvm_flags_on(st);
 839   }
 840   if (num_jvm_args() > 0) {
 841     st->print("jvm_args: "); print_jvm_args_on(st);
 842   }
 843   st->print_cr("java_command: %s", java_command() ? java_command() : "<unknown>");
 844   if (_java_class_path != NULL) {
 845     char* path = _java_class_path->value();
 846     st->print_cr("java_class_path (initial): %s", strlen(path) == 0 ? "<not set>" : path );
 847   }
 848   st->print_cr("Launcher Type: %s", _sun_java_launcher);
 849 }
 850 
 851 void Arguments::print_jvm_flags_on(outputStream* st) {
 852   if (_num_jvm_flags > 0) {
 853     for (int i=0; i < _num_jvm_flags; i++) {
 854       st->print("%s ", _jvm_flags_array[i]);
 855     }
 856     st->cr();
 857   }
 858 }
 859 
 860 void Arguments::print_jvm_args_on(outputStream* st) {
 861   if (_num_jvm_args > 0) {
 862     for (int i=0; i < _num_jvm_args; i++) {
 863       st->print("%s ", _jvm_args_array[i]);
 864     }
 865     st->cr();
 866   }
 867 }
 868 
 869 bool Arguments::process_argument(const char* arg,
 870     jboolean ignore_unrecognized, Flag::Flags origin) {
 871 
 872   JDK_Version since = JDK_Version();
 873 
 874   if (parse_argument(arg, origin) || ignore_unrecognized) {
 875     return true;
 876   }
 877 
 878   bool has_plus_minus = (*arg == '+' || *arg == '-');
 879   const char* const argname = has_plus_minus ? arg + 1 : arg;
 880   if (is_newly_obsolete(arg, &since)) {
 881     char version[256];
 882     since.to_string(version, sizeof(version));
 883     warning("ignoring option %s; support was removed in %s", argname, version);
 884     return true;
 885   }
 886 
 887   // For locked flags, report a custom error message if available.
 888   // Otherwise, report the standard unrecognized VM option.
 889 
 890   size_t arg_len;
 891   const char* equal_sign = strchr(argname, '=');
 892   if (equal_sign == NULL) {
 893     arg_len = strlen(argname);
 894   } else {
 895     arg_len = equal_sign - argname;
 896   }
 897 
 898   Flag* found_flag = Flag::find_flag((const char*)argname, arg_len, true, true);
 899   if (found_flag != NULL) {
 900     char locked_message_buf[BUFLEN];
 901     found_flag->get_locked_message(locked_message_buf, BUFLEN);
 902     if (strlen(locked_message_buf) == 0) {
 903       if (found_flag->is_bool() && !has_plus_minus) {
 904         jio_fprintf(defaultStream::error_stream(),
 905           "Missing +/- setting for VM option '%s'\n", argname);
 906       } else if (!found_flag->is_bool() && has_plus_minus) {
 907         jio_fprintf(defaultStream::error_stream(),
 908           "Unexpected +/- setting in VM option '%s'\n", argname);
 909       } else {
 910         jio_fprintf(defaultStream::error_stream(),
 911           "Improperly specified VM option '%s'\n", argname);
 912       }
 913     } else {
 914       jio_fprintf(defaultStream::error_stream(), "%s", locked_message_buf);
 915     }
 916   } else {
 917     jio_fprintf(defaultStream::error_stream(),
 918                 "Unrecognized VM option '%s'\n", argname);
 919     Flag* fuzzy_matched = Flag::fuzzy_match((const char*)argname, arg_len, true);
 920     if (fuzzy_matched != NULL) {
 921       jio_fprintf(defaultStream::error_stream(),
 922                   "Did you mean '%s%s%s'?\n",
 923                   (fuzzy_matched->is_bool()) ? "(+/-)" : "",
 924                   fuzzy_matched->_name,
 925                   (fuzzy_matched->is_bool()) ? "" : "=<value>");
 926     }
 927   }
 928 
 929   // allow for commandline "commenting out" options like -XX:#+Verbose
 930   return arg[0] == '#';
 931 }
 932 
 933 bool Arguments::process_settings_file(const char* file_name, bool should_exist, jboolean ignore_unrecognized) {
 934   FILE* stream = fopen(file_name, "rb");
 935   if (stream == NULL) {
 936     if (should_exist) {
 937       jio_fprintf(defaultStream::error_stream(),
 938                   "Could not open settings file %s\n", file_name);
 939       return false;
 940     } else {
 941       return true;
 942     }
 943   }
 944 
 945   char token[1024];
 946   int  pos = 0;
 947 
 948   bool in_white_space = true;
 949   bool in_comment     = false;
 950   bool in_quote       = false;
 951   char quote_c        = 0;
 952   bool result         = true;
 953 
 954   int c = getc(stream);
 955   while(c != EOF && pos < (int)(sizeof(token)-1)) {
 956     if (in_white_space) {
 957       if (in_comment) {
 958         if (c == '\n') in_comment = false;
 959       } else {
 960         if (c == '#') in_comment = true;
 961         else if (!isspace(c)) {
 962           in_white_space = false;
 963           token[pos++] = c;
 964         }
 965       }
 966     } else {
 967       if (c == '\n' || (!in_quote && isspace(c))) {
 968         // token ends at newline, or at unquoted whitespace
 969         // this allows a way to include spaces in string-valued options
 970         token[pos] = '\0';
 971         logOption(token);
 972         result &= process_argument(token, ignore_unrecognized, Flag::CONFIG_FILE);
 973         build_jvm_flags(token);
 974         pos = 0;
 975         in_white_space = true;
 976         in_quote = false;
 977       } else if (!in_quote && (c == '\'' || c == '"')) {
 978         in_quote = true;
 979         quote_c = c;
 980       } else if (in_quote && (c == quote_c)) {
 981         in_quote = false;
 982       } else {
 983         token[pos++] = c;
 984       }
 985     }
 986     c = getc(stream);
 987   }
 988   if (pos > 0) {
 989     token[pos] = '\0';
 990     result &= process_argument(token, ignore_unrecognized, Flag::CONFIG_FILE);
 991     build_jvm_flags(token);
 992   }
 993   fclose(stream);
 994   return result;
 995 }
 996 
 997 //=============================================================================================================
 998 // Parsing of properties (-D)
 999 
1000 const char* Arguments::get_property(const char* key) {
1001   return PropertyList_get_value(system_properties(), key);
1002 }
1003 
1004 bool Arguments::add_property(const char* prop) {
1005   const char* eq = strchr(prop, '=');
1006   char* key;
1007   // ns must be static--its address may be stored in a SystemProperty object.
1008   const static char ns[1] = {0};
1009   char* value = (char *)ns;
1010 
1011   size_t key_len = (eq == NULL) ? strlen(prop) : (eq - prop);
1012   key = AllocateHeap(key_len + 1, mtInternal);
1013   strncpy(key, prop, key_len);
1014   key[key_len] = '\0';
1015 
1016   if (eq != NULL) {
1017     size_t value_len = strlen(prop) - key_len - 1;
1018     value = AllocateHeap(value_len + 1, mtInternal);
1019     strncpy(value, &prop[key_len + 1], value_len + 1);
1020   }
1021 
1022   if (strcmp(key, "java.compiler") == 0) {
1023     process_java_compiler_argument(value);
1024     FreeHeap(key);
1025     if (eq != NULL) {
1026       FreeHeap(value);
1027     }
1028     return true;
1029   } else if (strcmp(key, "sun.java.command") == 0) {
1030     _java_command = value;
1031 
1032     // Record value in Arguments, but let it get passed to Java.
1033   } else if (strcmp(key, "sun.java.launcher.pid") == 0) {
1034     // launcher.pid property is private and is processed
1035     // in process_sun_java_launcher_properties();
1036     // the sun.java.launcher property is passed on to the java application
1037     FreeHeap(key);
1038     if (eq != NULL) {
1039       FreeHeap(value);
1040     }
1041     return true;
1042   } else if (strcmp(key, "java.vendor.url.bug") == 0) {
1043     // save it in _java_vendor_url_bug, so JVM fatal error handler can access
1044     // its value without going through the property list or making a Java call.
1045     _java_vendor_url_bug = value;
1046   } else if (strcmp(key, "sun.boot.library.path") == 0) {
1047     PropertyList_unique_add(&_system_properties, key, value, true);
1048     return true;
1049   }
1050   // Create new property and add at the end of the list
1051   PropertyList_unique_add(&_system_properties, key, value);
1052   return true;
1053 }
1054 
1055 //===========================================================================================================
1056 // Setting int/mixed/comp mode flags
1057 
1058 void Arguments::set_mode_flags(Mode mode) {
1059   // Set up default values for all flags.
1060   // If you add a flag to any of the branches below,
1061   // add a default value for it here.
1062   set_java_compiler(false);
1063   _mode                      = mode;
1064 
1065   // Ensure Agent_OnLoad has the correct initial values.
1066   // This may not be the final mode; mode may change later in onload phase.
1067   PropertyList_unique_add(&_system_properties, "java.vm.info",
1068                           (char*)VM_Version::vm_info_string(), false);
1069 
1070   UseInterpreter             = true;
1071   UseCompiler                = true;
1072   UseLoopCounter             = true;
1073 
1074 #ifndef ZERO
1075   // Turn these off for mixed and comp.  Leave them on for Zero.
1076   if (FLAG_IS_DEFAULT(UseFastAccessorMethods)) {
1077     UseFastAccessorMethods = (mode == _int);
1078   }
1079   if (FLAG_IS_DEFAULT(UseFastEmptyMethods)) {
1080     UseFastEmptyMethods = (mode == _int);
1081   }
1082 #endif
1083 
1084   // Default values may be platform/compiler dependent -
1085   // use the saved values
1086   ClipInlining               = Arguments::_ClipInlining;
1087   AlwaysCompileLoopMethods   = Arguments::_AlwaysCompileLoopMethods;
1088   UseOnStackReplacement      = Arguments::_UseOnStackReplacement;
1089   BackgroundCompilation      = Arguments::_BackgroundCompilation;
1090 
1091   // Change from defaults based on mode
1092   switch (mode) {
1093   default:
1094     ShouldNotReachHere();
1095     break;
1096   case _int:
1097     UseCompiler              = false;
1098     UseLoopCounter           = false;
1099     AlwaysCompileLoopMethods = false;
1100     UseOnStackReplacement    = false;
1101     break;
1102   case _mixed:
1103     // same as default
1104     break;
1105   case _comp:
1106     UseInterpreter           = false;
1107     BackgroundCompilation    = false;
1108     ClipInlining             = false;
1109     // Be much more aggressive in tiered mode with -Xcomp and exercise C2 more.
1110     // We will first compile a level 3 version (C1 with full profiling), then do one invocation of it and
1111     // compile a level 4 (C2) and then continue executing it.
1112     if (TieredCompilation) {
1113       Tier3InvokeNotifyFreqLog = 0;
1114       Tier4InvocationThreshold = 0;
1115     }
1116     break;
1117   }
1118 }
1119 
1120 #if defined(COMPILER2) || defined(_LP64) || !INCLUDE_CDS
1121 // Conflict: required to use shared spaces (-Xshare:on), but
1122 // incompatible command line options were chosen.
1123 
1124 static void no_shared_spaces(const char* message) {
1125   if (RequireSharedSpaces) {
1126     jio_fprintf(defaultStream::error_stream(),
1127       "Class data sharing is inconsistent with other specified options.\n");
1128     vm_exit_during_initialization("Unable to use shared archive.", message);
1129   } else {
1130     FLAG_SET_DEFAULT(UseSharedSpaces, false);
1131   }
1132 }
1133 #endif
1134 
1135 void Arguments::set_tiered_flags() {
1136   // With tiered, set default policy to AdvancedThresholdPolicy, which is 3.
1137   if (FLAG_IS_DEFAULT(CompilationPolicyChoice)) {
1138     FLAG_SET_DEFAULT(CompilationPolicyChoice, 3);
1139   }
1140   if (CompilationPolicyChoice < 2) {
1141     vm_exit_during_initialization(
1142       "Incompatible compilation policy selected", NULL);
1143   }
1144   // Increase the code cache size - tiered compiles a lot more.
1145   if (FLAG_IS_DEFAULT(ReservedCodeCacheSize)) {
1146     NOT_AARCH64(FLAG_SET_DEFAULT(ReservedCodeCacheSize, ReservedCodeCacheSize * 5));
1147     AARCH64_ONLY(FLAG_SET_DEFAULT(ReservedCodeCacheSize,
1148                                   MIN2(CODE_CACHE_DEFAULT_LIMIT, ReservedCodeCacheSize * 5)));
1149   }
1150   if (!UseInterpreter) { // -Xcomp
1151     Tier3InvokeNotifyFreqLog = 0;
1152     Tier4InvocationThreshold = 0;
1153   }
1154 }
1155 
1156 /**
1157  * Returns the minimum number of compiler threads needed to run the JVM. The following
1158  * configurations are possible.
1159  *
1160  * 1) The JVM is build using an interpreter only. As a result, the minimum number of
1161  *    compiler threads is 0.
1162  * 2) The JVM is build using the compiler(s) and tiered compilation is disabled. As
1163  *    a result, either C1 or C2 is used, so the minimum number of compiler threads is 1.
1164  * 3) The JVM is build using the compiler(s) and tiered compilation is enabled. However,
1165  *    the option "TieredStopAtLevel < CompLevel_full_optimization". As a result, only
1166  *    C1 can be used, so the minimum number of compiler threads is 1.
1167  * 4) The JVM is build using the compilers and tiered compilation is enabled. The option
1168  *    'TieredStopAtLevel = CompLevel_full_optimization' (the default value). As a result,
1169  *    the minimum number of compiler threads is 2.
1170  */
1171 int Arguments::get_min_number_of_compiler_threads() {
1172 #if !defined(COMPILER1) && !defined(COMPILER2) && !defined(SHARK)
1173   return 0;   // case 1
1174 #else
1175   if (!TieredCompilation || (TieredStopAtLevel < CompLevel_full_optimization)) {
1176     return 1; // case 2 or case 3
1177   }
1178   return 2;   // case 4 (tiered)
1179 #endif
1180 }
1181 
1182 #if INCLUDE_ALL_GCS
1183 static void disable_adaptive_size_policy(const char* collector_name) {
1184   if (UseAdaptiveSizePolicy) {
1185     if (FLAG_IS_CMDLINE(UseAdaptiveSizePolicy)) {
1186       warning("disabling UseAdaptiveSizePolicy; it is incompatible with %s.",
1187               collector_name);
1188     }
1189     FLAG_SET_DEFAULT(UseAdaptiveSizePolicy, false);
1190   }
1191 }
1192 
1193 void Arguments::set_parnew_gc_flags() {
1194   assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC && !UseG1GC,
1195          "control point invariant");
1196   assert(UseParNewGC, "Error");
1197 
1198   // Turn off AdaptiveSizePolicy for parnew until it is complete.
1199   disable_adaptive_size_policy("UseParNewGC");
1200 
1201   if (FLAG_IS_DEFAULT(ParallelGCThreads)) {
1202     FLAG_SET_DEFAULT(ParallelGCThreads, Abstract_VM_Version::parallel_worker_threads());
1203     assert(ParallelGCThreads > 0, "We should always have at least one thread by default");
1204   } else if (ParallelGCThreads == 0) {
1205     jio_fprintf(defaultStream::error_stream(),
1206         "The ParNew GC can not be combined with -XX:ParallelGCThreads=0\n");
1207     vm_exit(1);
1208   }
1209 
1210   // By default YoungPLABSize and OldPLABSize are set to 4096 and 1024 respectively,
1211   // these settings are default for Parallel Scavenger. For ParNew+Tenured configuration
1212   // we set them to 1024 and 1024.
1213   // See CR 6362902.
1214   if (FLAG_IS_DEFAULT(YoungPLABSize)) {
1215     FLAG_SET_DEFAULT(YoungPLABSize, (intx)1024);
1216   }
1217   if (FLAG_IS_DEFAULT(OldPLABSize)) {
1218     FLAG_SET_DEFAULT(OldPLABSize, (intx)1024);
1219   }
1220 
1221   // AlwaysTenure flag should make ParNew promote all at first collection.
1222   // See CR 6362902.
1223   if (AlwaysTenure) {
1224     FLAG_SET_CMDLINE(uintx, MaxTenuringThreshold, 0);
1225   }
1226   // When using compressed oops, we use local overflow stacks,
1227   // rather than using a global overflow list chained through
1228   // the klass word of the object's pre-image.
1229   if (UseCompressedOops && !ParGCUseLocalOverflow) {
1230     if (!FLAG_IS_DEFAULT(ParGCUseLocalOverflow)) {
1231       warning("Forcing +ParGCUseLocalOverflow: needed if using compressed references");
1232     }
1233     FLAG_SET_DEFAULT(ParGCUseLocalOverflow, true);
1234   }
1235   assert(ParGCUseLocalOverflow || !UseCompressedOops, "Error");
1236 }
1237 
1238 // Adjust some sizes to suit CMS and/or ParNew needs; these work well on
1239 // sparc/solaris for certain applications, but would gain from
1240 // further optimization and tuning efforts, and would almost
1241 // certainly gain from analysis of platform and environment.
1242 void Arguments::set_cms_and_parnew_gc_flags() {
1243   assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC, "Error");
1244   assert(UseConcMarkSweepGC, "CMS is expected to be on here");
1245 
1246   // If we are using CMS, we prefer to UseParNewGC,
1247   // unless explicitly forbidden.
1248   if (FLAG_IS_DEFAULT(UseParNewGC)) {
1249     FLAG_SET_ERGO(bool, UseParNewGC, true);
1250   }
1251 
1252   // Turn off AdaptiveSizePolicy by default for cms until it is complete.
1253   disable_adaptive_size_policy("UseConcMarkSweepGC");
1254 
1255   // In either case, adjust ParallelGCThreads and/or UseParNewGC
1256   // as needed.
1257   if (UseParNewGC) {
1258     set_parnew_gc_flags();
1259   }
1260 
1261   size_t max_heap = align_size_down(MaxHeapSize,
1262                                     CardTableRS::ct_max_alignment_constraint());
1263 
1264   // Now make adjustments for CMS
1265   intx   tenuring_default = (intx)6;
1266   size_t young_gen_per_worker = CMSYoungGenPerWorker;
1267 
1268   // Preferred young gen size for "short" pauses:
1269   // upper bound depends on # of threads and NewRatio.
1270   const uintx parallel_gc_threads =
1271     (ParallelGCThreads == 0 ? 1 : ParallelGCThreads);
1272   const size_t preferred_max_new_size_unaligned =
1273     MIN2(max_heap/(NewRatio+1), ScaleForWordSize(young_gen_per_worker * parallel_gc_threads));
1274   size_t preferred_max_new_size =
1275     align_size_up(preferred_max_new_size_unaligned, os::vm_page_size());
1276 
1277   // Unless explicitly requested otherwise, size young gen
1278   // for "short" pauses ~ CMSYoungGenPerWorker*ParallelGCThreads
1279 
1280   // If either MaxNewSize or NewRatio is set on the command line,
1281   // assume the user is trying to set the size of the young gen.
1282   if (FLAG_IS_DEFAULT(MaxNewSize) && FLAG_IS_DEFAULT(NewRatio)) {
1283 
1284     // Set MaxNewSize to our calculated preferred_max_new_size unless
1285     // NewSize was set on the command line and it is larger than
1286     // preferred_max_new_size.
1287     if (!FLAG_IS_DEFAULT(NewSize)) {   // NewSize explicitly set at command-line
1288       FLAG_SET_ERGO(uintx, MaxNewSize, MAX2(NewSize, preferred_max_new_size));
1289     } else {
1290       FLAG_SET_ERGO(uintx, MaxNewSize, preferred_max_new_size);
1291     }
1292     if (PrintGCDetails && Verbose) {
1293       // Too early to use gclog_or_tty
1294       tty->print_cr("CMS ergo set MaxNewSize: " SIZE_FORMAT, MaxNewSize);
1295     }
1296 
1297     // Code along this path potentially sets NewSize and OldSize
1298     if (PrintGCDetails && Verbose) {
1299       // Too early to use gclog_or_tty
1300       tty->print_cr("CMS set min_heap_size: " SIZE_FORMAT
1301            " initial_heap_size:  " SIZE_FORMAT
1302            " max_heap: " SIZE_FORMAT,
1303            min_heap_size(), InitialHeapSize, max_heap);
1304     }
1305     size_t min_new = preferred_max_new_size;
1306     if (FLAG_IS_CMDLINE(NewSize)) {
1307       min_new = NewSize;
1308     }
1309     if (max_heap > min_new && min_heap_size() > min_new) {
1310       // Unless explicitly requested otherwise, make young gen
1311       // at least min_new, and at most preferred_max_new_size.
1312       if (FLAG_IS_DEFAULT(NewSize)) {
1313         FLAG_SET_ERGO(uintx, NewSize, MAX2(NewSize, min_new));
1314         FLAG_SET_ERGO(uintx, NewSize, MIN2(preferred_max_new_size, NewSize));
1315         if (PrintGCDetails && Verbose) {
1316           // Too early to use gclog_or_tty
1317           tty->print_cr("CMS ergo set NewSize: " SIZE_FORMAT, NewSize);
1318         }
1319       }
1320       // Unless explicitly requested otherwise, size old gen
1321       // so it's NewRatio x of NewSize.
1322       if (FLAG_IS_DEFAULT(OldSize)) {
1323         if (max_heap > NewSize) {
1324           FLAG_SET_ERGO(uintx, OldSize, MIN2(NewRatio*NewSize, max_heap - NewSize));
1325           if (PrintGCDetails && Verbose) {
1326             // Too early to use gclog_or_tty
1327             tty->print_cr("CMS ergo set OldSize: " SIZE_FORMAT, OldSize);
1328           }
1329         }
1330       }
1331     }
1332   }
1333   // Unless explicitly requested otherwise, definitely
1334   // promote all objects surviving "tenuring_default" scavenges.
1335   if (FLAG_IS_DEFAULT(MaxTenuringThreshold) &&
1336       FLAG_IS_DEFAULT(SurvivorRatio)) {
1337     FLAG_SET_ERGO(uintx, MaxTenuringThreshold, tenuring_default);
1338   }
1339   // If we decided above (or user explicitly requested)
1340   // `promote all' (via MaxTenuringThreshold := 0),
1341   // prefer minuscule survivor spaces so as not to waste
1342   // space for (non-existent) survivors
1343   if (FLAG_IS_DEFAULT(SurvivorRatio) && MaxTenuringThreshold == 0) {
1344     FLAG_SET_ERGO(uintx, SurvivorRatio, MAX2((uintx)1024, SurvivorRatio));
1345   }
1346   // If OldPLABSize is set and CMSParPromoteBlocksToClaim is not,
1347   // set CMSParPromoteBlocksToClaim equal to OldPLABSize.
1348   // This is done in order to make ParNew+CMS configuration to work
1349   // with YoungPLABSize and OldPLABSize options.
1350   // See CR 6362902.
1351   if (!FLAG_IS_DEFAULT(OldPLABSize)) {
1352     if (FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim)) {
1353       // OldPLABSize is not the default value but CMSParPromoteBlocksToClaim
1354       // is.  In this situtation let CMSParPromoteBlocksToClaim follow
1355       // the value (either from the command line or ergonomics) of
1356       // OldPLABSize.  Following OldPLABSize is an ergonomics decision.
1357       FLAG_SET_ERGO(uintx, CMSParPromoteBlocksToClaim, OldPLABSize);
1358     } else {
1359       // OldPLABSize and CMSParPromoteBlocksToClaim are both set.
1360       // CMSParPromoteBlocksToClaim is a collector-specific flag, so
1361       // we'll let it to take precedence.
1362       jio_fprintf(defaultStream::error_stream(),
1363                   "Both OldPLABSize and CMSParPromoteBlocksToClaim"
1364                   " options are specified for the CMS collector."
1365                   " CMSParPromoteBlocksToClaim will take precedence.\n");
1366     }
1367   }
1368   if (!FLAG_IS_DEFAULT(ResizeOldPLAB) && !ResizeOldPLAB) {
1369     // OldPLAB sizing manually turned off: Use a larger default setting,
1370     // unless it was manually specified. This is because a too-low value
1371     // will slow down scavenges.
1372     if (FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim)) {
1373       FLAG_SET_ERGO(uintx, CMSParPromoteBlocksToClaim, 50); // default value before 6631166
1374     }
1375   }
1376   // Overwrite OldPLABSize which is the variable we will internally use everywhere.
1377   FLAG_SET_ERGO(uintx, OldPLABSize, CMSParPromoteBlocksToClaim);
1378   // If either of the static initialization defaults have changed, note this
1379   // modification.
1380   if (!FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim) || !FLAG_IS_DEFAULT(OldPLABWeight)) {
1381     CFLS_LAB::modify_initialization(OldPLABSize, OldPLABWeight);
1382   }
1383 
1384   if (!ClassUnloading) {
1385     FLAG_SET_CMDLINE(bool, CMSClassUnloadingEnabled, false);
1386     FLAG_SET_CMDLINE(bool, ExplicitGCInvokesConcurrentAndUnloadsClasses, false);
1387     FLAG_SET_CMDLINE(uintx, ShenandoahUnloadClassesFrequency, 0);
1388   }
1389 
1390   if (PrintGCDetails && Verbose) {
1391     tty->print_cr("MarkStackSize: %uk  MarkStackSizeMax: %uk",
1392       (unsigned int) (MarkStackSize / K), (uint) (MarkStackSizeMax / K));
1393     tty->print_cr("ConcGCThreads: %u", (uint) ConcGCThreads);
1394   }
1395 }
1396 #endif // INCLUDE_ALL_GCS
1397 
1398 void set_object_alignment() {
1399   // Object alignment.
1400   assert(is_power_of_2(ObjectAlignmentInBytes), "ObjectAlignmentInBytes must be power of 2");
1401   MinObjAlignmentInBytes     = ObjectAlignmentInBytes;
1402   assert(MinObjAlignmentInBytes >= HeapWordsPerLong * HeapWordSize, "ObjectAlignmentInBytes value is too small");
1403   MinObjAlignment            = MinObjAlignmentInBytes / HeapWordSize;
1404   assert(MinObjAlignmentInBytes == MinObjAlignment * HeapWordSize, "ObjectAlignmentInBytes value is incorrect");
1405   MinObjAlignmentInBytesMask = MinObjAlignmentInBytes - 1;
1406 
1407   LogMinObjAlignmentInBytes  = exact_log2(ObjectAlignmentInBytes);
1408   LogMinObjAlignment         = LogMinObjAlignmentInBytes - LogHeapWordSize;
1409 
1410   // Oop encoding heap max
1411   OopEncodingHeapMax = (uint64_t(max_juint) + 1) << LogMinObjAlignmentInBytes;
1412 
1413 #if INCLUDE_ALL_GCS
1414   // Set CMS global values
1415   CompactibleFreeListSpace::set_cms_values();
1416 #endif // INCLUDE_ALL_GCS
1417 }
1418 
1419 bool verify_object_alignment() {
1420   // Object alignment.
1421   if (!is_power_of_2(ObjectAlignmentInBytes)) {
1422     jio_fprintf(defaultStream::error_stream(),
1423                 "error: ObjectAlignmentInBytes=%d must be power of 2\n",
1424                 (int)ObjectAlignmentInBytes);
1425     return false;
1426   }
1427   if ((int)ObjectAlignmentInBytes < BytesPerLong) {
1428     jio_fprintf(defaultStream::error_stream(),
1429                 "error: ObjectAlignmentInBytes=%d must be greater or equal %d\n",
1430                 (int)ObjectAlignmentInBytes, BytesPerLong);
1431     return false;
1432   }
1433   // It does not make sense to have big object alignment
1434   // since a space lost due to alignment will be greater
1435   // then a saved space from compressed oops.
1436   if ((int)ObjectAlignmentInBytes > 256) {
1437     jio_fprintf(defaultStream::error_stream(),
1438                 "error: ObjectAlignmentInBytes=%d must not be greater than 256\n",
1439                 (int)ObjectAlignmentInBytes);
1440     return false;
1441   }
1442   // In case page size is very small.
1443   if ((int)ObjectAlignmentInBytes >= os::vm_page_size()) {
1444     jio_fprintf(defaultStream::error_stream(),
1445                 "error: ObjectAlignmentInBytes=%d must be less than page size %d\n",
1446                 (int)ObjectAlignmentInBytes, os::vm_page_size());
1447     return false;
1448   }
1449   if(SurvivorAlignmentInBytes == 0) {
1450     SurvivorAlignmentInBytes = ObjectAlignmentInBytes;
1451   } else {
1452     if (!is_power_of_2(SurvivorAlignmentInBytes)) {
1453       jio_fprintf(defaultStream::error_stream(),
1454             "error: SurvivorAlignmentInBytes=%d must be power of 2\n",
1455             (int)SurvivorAlignmentInBytes);
1456       return false;
1457     }
1458     if (SurvivorAlignmentInBytes < ObjectAlignmentInBytes) {
1459       jio_fprintf(defaultStream::error_stream(),
1460           "error: SurvivorAlignmentInBytes=%d must be greater than ObjectAlignmentInBytes=%d \n",
1461           (int)SurvivorAlignmentInBytes, (int)ObjectAlignmentInBytes);
1462       return false;
1463     }
1464   }
1465   return true;
1466 }
1467 
1468 size_t Arguments::max_heap_for_compressed_oops() {
1469   // Avoid sign flip.
1470   assert(OopEncodingHeapMax > (uint64_t)os::vm_page_size(), "Unusual page size");
1471   // We need to fit both the NULL page and the heap into the memory budget, while
1472   // keeping alignment constraints of the heap. To guarantee the latter, as the
1473   // NULL page is located before the heap, we pad the NULL page to the conservative
1474   // maximum alignment that the GC may ever impose upon the heap.
1475   size_t displacement_due_to_null_page = align_size_up_(os::vm_page_size(),
1476                                                         _conservative_max_heap_alignment);
1477 
1478   LP64_ONLY(return OopEncodingHeapMax - displacement_due_to_null_page);
1479   NOT_LP64(ShouldNotReachHere(); return 0);
1480 }
1481 
1482 bool Arguments::should_auto_select_low_pause_collector() {
1483   if (UseAutoGCSelectPolicy &&
1484       !FLAG_IS_DEFAULT(MaxGCPauseMillis) &&
1485       (MaxGCPauseMillis <= AutoGCSelectPauseMillis)) {
1486     if (PrintGCDetails) {
1487       // Cannot use gclog_or_tty yet.
1488       tty->print_cr("Automatic selection of the low pause collector"
1489        " based on pause goal of %d (ms)", (int) MaxGCPauseMillis);
1490     }
1491     return true;
1492   }
1493   return false;
1494 }
1495 
1496 void Arguments::set_use_compressed_oops() {
1497 #ifndef ZERO
1498 #ifdef _LP64
1499   // MaxHeapSize is not set up properly at this point, but
1500   // the only value that can override MaxHeapSize if we are
1501   // to use UseCompressedOops is InitialHeapSize.
1502   size_t max_heap_size = MAX2(MaxHeapSize, InitialHeapSize);
1503 
1504   if (max_heap_size <= max_heap_for_compressed_oops()) {
1505 #if !defined(COMPILER1) || defined(TIERED)
1506     if (FLAG_IS_DEFAULT(UseCompressedOops)) {
1507       FLAG_SET_ERGO(bool, UseCompressedOops, true);
1508     }
1509 #endif
1510 #ifdef _WIN64
1511     if (UseLargePages && UseCompressedOops) {
1512       // Cannot allocate guard pages for implicit checks in indexed addressing
1513       // mode, when large pages are specified on windows.
1514       // This flag could be switched ON if narrow oop base address is set to 0,
1515       // see code in Universe::initialize_heap().
1516       Universe::set_narrow_oop_use_implicit_null_checks(false);
1517     }
1518 #endif //  _WIN64
1519   } else {
1520     if (UseCompressedOops && !FLAG_IS_DEFAULT(UseCompressedOops)) {
1521       warning("Max heap size too large for Compressed Oops");
1522       FLAG_SET_DEFAULT(UseCompressedOops, false);
1523       FLAG_SET_DEFAULT(UseCompressedClassPointers, false);
1524     }
1525   }
1526 #endif // _LP64
1527 #endif // ZERO
1528 }
1529 
1530 // NOTE: set_use_compressed_klass_ptrs() must be called after calling
1531 // set_use_compressed_oops().
1532 void Arguments::set_use_compressed_klass_ptrs() {
1533 #ifndef ZERO
1534 #ifdef _LP64
1535   // UseCompressedOops must be on for UseCompressedClassPointers to be on.
1536   if (!UseCompressedOops) {
1537     if (UseCompressedClassPointers) {
1538       warning("UseCompressedClassPointers requires UseCompressedOops");
1539     }
1540     FLAG_SET_DEFAULT(UseCompressedClassPointers, false);
1541   } else {
1542     // Turn on UseCompressedClassPointers too
1543     if (FLAG_IS_DEFAULT(UseCompressedClassPointers)) {
1544       FLAG_SET_ERGO(bool, UseCompressedClassPointers, true);
1545     }
1546     // Check the CompressedClassSpaceSize to make sure we use compressed klass ptrs.
1547     if (UseCompressedClassPointers) {
1548       if (CompressedClassSpaceSize > KlassEncodingMetaspaceMax) {
1549         warning("CompressedClassSpaceSize is too large for UseCompressedClassPointers");
1550         FLAG_SET_DEFAULT(UseCompressedClassPointers, false);
1551       }
1552     }
1553   }
1554 #endif // _LP64
1555 #endif // !ZERO
1556 }
1557 
1558 void Arguments::set_conservative_max_heap_alignment() {
1559   // The conservative maximum required alignment for the heap is the maximum of
1560   // the alignments imposed by several sources: any requirements from the heap
1561   // itself, the collector policy and the maximum page size we may run the VM
1562   // with.
1563   size_t heap_alignment = GenCollectedHeap::conservative_max_heap_alignment();
1564 #if INCLUDE_ALL_GCS
1565   if (UseParallelGC) {
1566     heap_alignment = ParallelScavengeHeap::conservative_max_heap_alignment();
1567   } else if (UseG1GC) {
1568     heap_alignment = G1CollectedHeap::conservative_max_heap_alignment();
1569   } else if (UseShenandoahGC) {
1570     heap_alignment = ShenandoahHeap::conservative_max_heap_alignment();
1571   }
1572 #endif // INCLUDE_ALL_GCS
1573   _conservative_max_heap_alignment = MAX4(heap_alignment,
1574                                           (size_t)os::vm_allocation_granularity(),
1575                                           os::max_page_size(),
1576                                           CollectorPolicy::compute_heap_alignment());
1577 }
1578 
1579 void Arguments::select_gc_ergonomically() {
1580   if (os::is_server_class_machine()) {
1581     if (should_auto_select_low_pause_collector()) {
1582       FLAG_SET_ERGO(bool, UseConcMarkSweepGC, true);
1583     } else {
1584       FLAG_SET_ERGO(bool, UseParallelGC, true);
1585     }
1586   }
1587 }
1588 
1589 void Arguments::select_gc() {
1590   if (!gc_selected()) {
1591     select_gc_ergonomically();
1592   }
1593 }
1594 
1595 void Arguments::set_ergonomics_flags() {
1596   select_gc();
1597 
1598 #ifdef COMPILER2
1599   // Shared spaces work fine with other GCs but causes bytecode rewriting
1600   // to be disabled, which hurts interpreter performance and decreases
1601   // server performance.  When -server is specified, keep the default off
1602   // unless it is asked for.  Future work: either add bytecode rewriting
1603   // at link time, or rewrite bytecodes in non-shared methods.
1604   if (!DumpSharedSpaces && !RequireSharedSpaces &&
1605       (FLAG_IS_DEFAULT(UseSharedSpaces) || !UseSharedSpaces)) {
1606     no_shared_spaces("COMPILER2 default: -Xshare:auto | off, have to manually setup to on.");
1607   }
1608 #endif
1609 
1610   set_conservative_max_heap_alignment();
1611 
1612 #ifndef ZERO
1613 #ifdef _LP64
1614   set_use_compressed_oops();
1615 
1616   // set_use_compressed_klass_ptrs() must be called after calling
1617   // set_use_compressed_oops().
1618   set_use_compressed_klass_ptrs();
1619 
1620   // Also checks that certain machines are slower with compressed oops
1621   // in vm_version initialization code.
1622 #endif // _LP64
1623 #endif // !ZERO
1624 }
1625 
1626 void Arguments::set_parallel_gc_flags() {
1627   assert(UseParallelGC || UseParallelOldGC, "Error");
1628   // Enable ParallelOld unless it was explicitly disabled (cmd line or rc file).
1629   if (FLAG_IS_DEFAULT(UseParallelOldGC)) {
1630     FLAG_SET_DEFAULT(UseParallelOldGC, true);
1631   }
1632   FLAG_SET_DEFAULT(UseParallelGC, true);
1633 
1634   // If no heap maximum was requested explicitly, use some reasonable fraction
1635   // of the physical memory, up to a maximum of 1GB.
1636   FLAG_SET_DEFAULT(ParallelGCThreads,
1637                    Abstract_VM_Version::parallel_worker_threads());
1638   if (ParallelGCThreads == 0) {
1639     jio_fprintf(defaultStream::error_stream(),
1640         "The Parallel GC can not be combined with -XX:ParallelGCThreads=0\n");
1641     vm_exit(1);
1642   }
1643 
1644   if (UseAdaptiveSizePolicy) {
1645     // We don't want to limit adaptive heap sizing's freedom to adjust the heap
1646     // unless the user actually sets these flags.
1647     if (FLAG_IS_DEFAULT(MinHeapFreeRatio)) {
1648       FLAG_SET_DEFAULT(MinHeapFreeRatio, 0);
1649       _min_heap_free_ratio = MinHeapFreeRatio;
1650     }
1651     if (FLAG_IS_DEFAULT(MaxHeapFreeRatio)) {
1652       FLAG_SET_DEFAULT(MaxHeapFreeRatio, 100);
1653       _max_heap_free_ratio = MaxHeapFreeRatio;
1654     }
1655   }
1656 
1657   // If InitialSurvivorRatio or MinSurvivorRatio were not specified, but the
1658   // SurvivorRatio has been set, reset their default values to SurvivorRatio +
1659   // 2.  By doing this we make SurvivorRatio also work for Parallel Scavenger.
1660   // See CR 6362902 for details.
1661   if (!FLAG_IS_DEFAULT(SurvivorRatio)) {
1662     if (FLAG_IS_DEFAULT(InitialSurvivorRatio)) {
1663        FLAG_SET_DEFAULT(InitialSurvivorRatio, SurvivorRatio + 2);
1664     }
1665     if (FLAG_IS_DEFAULT(MinSurvivorRatio)) {
1666       FLAG_SET_DEFAULT(MinSurvivorRatio, SurvivorRatio + 2);
1667     }
1668   }
1669 
1670   if (UseParallelOldGC) {
1671     // Par compact uses lower default values since they are treated as
1672     // minimums.  These are different defaults because of the different
1673     // interpretation and are not ergonomically set.
1674     if (FLAG_IS_DEFAULT(MarkSweepDeadRatio)) {
1675       FLAG_SET_DEFAULT(MarkSweepDeadRatio, 1);
1676     }
1677   }
1678 }
1679 
1680 void Arguments::set_g1_gc_flags() {
1681   assert(UseG1GC, "Error");
1682 #ifdef COMPILER1
1683   FastTLABRefill = false;
1684 #endif
1685   FLAG_SET_DEFAULT(ParallelGCThreads,
1686                      Abstract_VM_Version::parallel_worker_threads());
1687   if (ParallelGCThreads == 0) {
1688     vm_exit_during_initialization("The flag -XX:+UseG1GC can not be combined with -XX:ParallelGCThreads=0", NULL);
1689     }
1690 
1691 #if INCLUDE_ALL_GCS
1692   if (G1ConcRefinementThreads == 0) {
1693     FLAG_SET_DEFAULT(G1ConcRefinementThreads, ParallelGCThreads);
1694   }
1695 #endif
1696 
1697   // MarkStackSize will be set (if it hasn't been set by the user)
1698   // when concurrent marking is initialized.
1699   // Its value will be based upon the number of parallel marking threads.
1700   // But we do set the maximum mark stack size here.
1701   if (FLAG_IS_DEFAULT(MarkStackSizeMax)) {
1702     FLAG_SET_DEFAULT(MarkStackSizeMax, 128 * TASKQUEUE_SIZE);
1703   }
1704 
1705   if (FLAG_IS_DEFAULT(GCTimeRatio) || GCTimeRatio == 0) {
1706     // In G1, we want the default GC overhead goal to be higher than
1707     // say in PS. So we set it here to 10%. Otherwise the heap might
1708     // be expanded more aggressively than we would like it to. In
1709     // fact, even 10% seems to not be high enough in some cases
1710     // (especially small GC stress tests that the main thing they do
1711     // is allocation). We might consider increase it further.
1712     FLAG_SET_DEFAULT(GCTimeRatio, 9);
1713   }
1714 
1715   if (PrintGCDetails && Verbose) {
1716     tty->print_cr("MarkStackSize: %uk  MarkStackSizeMax: %uk",
1717       (unsigned int) (MarkStackSize / K), (uint) (MarkStackSizeMax / K));
1718     tty->print_cr("ConcGCThreads: %u", (uint) ConcGCThreads);
1719   }
1720 }
1721 
1722 void Arguments::set_shenandoah_gc_flags() {
1723 
1724 #if !(defined AARCH64 || defined AMD64 || defined IA32)
1725   UNSUPPORTED_GC_OPTION(UseShenandoahGC);
1726 #endif
1727 
1728 #ifdef IA32
1729   warning("Shenandoah GC is not fully supported on this platform:");
1730   warning("  concurrent modes are not supported, only STW cycles are enabled;");
1731   warning("  arch-specific barrier code is not implemented, disabling barriers;");
1732 
1733 #if INCLUDE_ALL_GCS
1734   FLAG_SET_DEFAULT(ShenandoahGCHeuristics,           "passive");
1735 
1736   FLAG_SET_DEFAULT(ShenandoahSATBBarrier,            false);
1737   FLAG_SET_DEFAULT(ShenandoahWriteBarrier,           false);
1738   FLAG_SET_DEFAULT(ShenandoahReadBarrier,            false);
1739   FLAG_SET_DEFAULT(ShenandoahCASBarrier,             false);
1740   FLAG_SET_DEFAULT(ShenandoahAcmpBarrier,            false);
1741   FLAG_SET_DEFAULT(ShenandoahCloneBarrier,           false);
1742 #endif
1743 #endif
1744 
1745 #if INCLUDE_ALL_GCS
1746   if (!FLAG_IS_DEFAULT(ShenandoahGarbageThreshold)) {
1747     if (0 > ShenandoahGarbageThreshold || ShenandoahGarbageThreshold > 100) {
1748       vm_exit_during_initialization("The flag -XX:ShenandoahGarbageThreshold is out of range", NULL);
1749     }
1750   }
1751 
1752   if (!FLAG_IS_DEFAULT(ShenandoahAllocationThreshold)) {
1753     if (0 > ShenandoahAllocationThreshold || ShenandoahAllocationThreshold > 100) {
1754       vm_exit_during_initialization("The flag -XX:ShenandoahAllocationThreshold is out of range", NULL);
1755     }
1756   }
1757 
1758   if (!FLAG_IS_DEFAULT(ShenandoahFreeThreshold)) {
1759     if (0 > ShenandoahFreeThreshold || ShenandoahFreeThreshold > 100) {
1760       vm_exit_during_initialization("The flag -XX:ShenandoahFreeThreshold is out of range", NULL);
1761     }
1762   }
1763 #endif
1764 
1765 #ifdef _LP64
1766   // The optimized ObjArrayChunkedTask takes some bits away from the full 64 addressable
1767   // bits, fail if we ever attempt to address more than we can. Only valid on 64bit.
1768   if (MaxHeapSize >= ObjArrayChunkedTask::max_addressable()) {
1769     jio_fprintf(defaultStream::error_stream(),
1770                 "Shenandoah GC cannot address more than " SIZE_FORMAT " bytes, and " SIZE_FORMAT " bytes heap requested.",
1771                 ObjArrayChunkedTask::max_addressable(), MaxHeapSize);
1772     vm_exit(1);
1773   }
1774 #endif
1775 
1776   FLAG_SET_DEFAULT(ParallelGCThreads,
1777                    Abstract_VM_Version::parallel_worker_threads());
1778 
1779   if (FLAG_IS_DEFAULT(ConcGCThreads)) {
1780     uint conc_threads = MAX2((uint) 1, (uint)ParallelGCThreads);
1781     FLAG_SET_DEFAULT(ConcGCThreads, conc_threads);
1782   }
1783 
1784   if (FLAG_IS_DEFAULT(ParallelRefProcEnabled)) {
1785     FLAG_SET_DEFAULT(ParallelRefProcEnabled, true);
1786   }
1787 
1788 #if INCLUDE_ALL_GCS
1789   if (ShenandoahRegionSampling && FLAG_IS_DEFAULT(PerfDataMemorySize)) {
1790     // When sampling is enabled, max out the PerfData memory to get more
1791     // Shenandoah data in, including Matrix.
1792     FLAG_SET_DEFAULT(PerfDataMemorySize, 2048*K);
1793   }
1794 #endif
1795 
1796 #ifdef COMPILER2
1797   // Shenandoah cares more about pause times, rather than raw throughput.
1798   // Enabling safepoints in counted loops makes it more responsive with
1799   // long loops.
1800   if (FLAG_IS_DEFAULT(UseCountedLoopSafepoints)) {
1801     FLAG_SET_DEFAULT(UseCountedLoopSafepoints, true);
1802   }
1803 
1804 #ifdef ASSERT
1805   // C2 barrier verification is only reliable when all default barriers are enabled
1806   if (ShenandoahVerifyOptoBarriers &&
1807           (!FLAG_IS_DEFAULT(ShenandoahSATBBarrier)    ||
1808            !FLAG_IS_DEFAULT(ShenandoahReadBarrier)    ||
1809            !FLAG_IS_DEFAULT(ShenandoahWriteBarrier)   ||
1810            !FLAG_IS_DEFAULT(ShenandoahCASBarrier)     ||
1811            !FLAG_IS_DEFAULT(ShenandoahAcmpBarrier)    ||
1812            !FLAG_IS_DEFAULT(ShenandoahCloneBarrier)
1813           )) {
1814     warning("Unusual barrier configuration, disabling C2 barrier verification");
1815     FLAG_SET_DEFAULT(ShenandoahVerifyOptoBarriers, false);
1816   }
1817 #else
1818   guarantee(!ShenandoahVerifyOptoBarriers, "Should be disabled");
1819 #endif // ASSERT
1820 #endif // COMPILER2
1821 
1822 #if INCLUDE_ALL_GCS
1823   if (AlwaysPreTouch) {
1824     // Shenandoah handles pre-touch on its own. It does not let the
1825     // generic storage code to do the pre-touch before Shenandoah has
1826     // a chance to do it on its own.
1827     FLAG_SET_DEFAULT(AlwaysPreTouch, false);
1828     FLAG_SET_DEFAULT(ShenandoahAlwaysPreTouch, true);
1829   }
1830 
1831   if (ShenandoahAlwaysPreTouch) {
1832     if (!FLAG_IS_DEFAULT(ShenandoahUncommit)) {
1833       warning("AlwaysPreTouch is enabled, disabling ShenandoahUncommit");
1834     }
1835     FLAG_SET_DEFAULT(ShenandoahUncommit, false);
1836   }
1837 
1838   // If class unloading is disabled, no unloading for concurrent cycles as well.
1839   // If class unloading is enabled, users should opt-in for unloading during
1840   // concurrent cycles.
1841   if (!ClassUnloading || !FLAG_IS_CMDLINE(ClassUnloadingWithConcurrentMark)) {
1842     if (PrintGC) {
1843       tty->print_cr("Consider -XX:+ClassUnloadingWithConcurrentMark if large pause times "
1844                     "are observed on class-unloading sensitive workloads");
1845     }
1846     FLAG_SET_DEFAULT(ClassUnloadingWithConcurrentMark, false);
1847   }
1848 
1849   // JNI fast get field stuff is not currently supported by Shenandoah.
1850   // It would introduce another heap memory access for reading the forwarding
1851   // pointer, which would have to be guarded by the signal handler machinery.
1852   // See:
1853   // http://mail.openjdk.java.net/pipermail/hotspot-dev/2018-June/032763.html
1854   FLAG_SET_DEFAULT(UseFastJNIAccessors, false);
1855 
1856   // TLAB sizing policy makes resizing decisions before each GC cycle. It averages
1857   // historical data, assigning more recent data the weight according to TLABAllocationWeight.
1858   // Current default is good for generational collectors that run frequent young GCs.
1859   // With Shenandoah, GC cycles are much less frequent, so we need we need sizing policy
1860   // to converge faster over smaller number of resizing decisions.
1861   if (FLAG_IS_DEFAULT(TLABAllocationWeight)) {
1862     FLAG_SET_DEFAULT(TLABAllocationWeight, 90);
1863   }
1864 
1865   // Shenandoah needs more C2 nodes to compile some methods with lots of barriers.
1866   // NodeLimitFudgeFactor needs to stay the same relative to MaxNodeLimit.
1867 #ifdef COMPILER2
1868   if (FLAG_IS_DEFAULT(MaxNodeLimit)) {
1869     FLAG_SET_DEFAULT(MaxNodeLimit, MaxNodeLimit * 3);
1870     FLAG_SET_DEFAULT(NodeLimitFudgeFactor, NodeLimitFudgeFactor * 3);
1871   }
1872 #endif
1873 #endif
1874 }
1875 
1876 #if !INCLUDE_ALL_GCS
1877 #ifdef ASSERT
1878 static bool verify_serial_gc_flags() {
1879   return (UseSerialGC &&
1880         !(UseParNewGC || (UseConcMarkSweepGC || CMSIncrementalMode) || UseG1GC ||
1881           UseParallelGC || UseParallelOldGC));
1882 }
1883 #endif // ASSERT
1884 #endif // INCLUDE_ALL_GCS
1885 
1886 void Arguments::set_gc_specific_flags() {
1887 #if INCLUDE_ALL_GCS
1888   // Set per-collector flags
1889   if (UseParallelGC || UseParallelOldGC) {
1890     set_parallel_gc_flags();
1891   } else if (UseConcMarkSweepGC) { // Should be done before ParNew check below
1892     set_cms_and_parnew_gc_flags();
1893   } else if (UseParNewGC) {  // Skipped if CMS is set above
1894     set_parnew_gc_flags();
1895   } else if (UseG1GC) {
1896     set_g1_gc_flags();
1897   } else if (UseShenandoahGC) {
1898     set_shenandoah_gc_flags();
1899   }
1900   check_deprecated_gcs();
1901   check_deprecated_gc_flags();
1902   if (AssumeMP && !UseSerialGC) {
1903     if (FLAG_IS_DEFAULT(ParallelGCThreads) && ParallelGCThreads == 1) {
1904       warning("If the number of processors is expected to increase from one, then"
1905               " you should configure the number of parallel GC threads appropriately"
1906               " using -XX:ParallelGCThreads=N");
1907     }
1908   }
1909   if (MinHeapFreeRatio == 100) {
1910     // Keeping the heap 100% free is hard ;-) so limit it to 99%.
1911     FLAG_SET_ERGO(uintx, MinHeapFreeRatio, 99);
1912   }
1913 #else // INCLUDE_ALL_GCS
1914   assert(verify_serial_gc_flags(), "SerialGC unset");
1915 #endif // INCLUDE_ALL_GCS
1916 }
1917 
1918 julong Arguments::limit_by_allocatable_memory(julong limit) {
1919   julong max_allocatable;
1920   julong result = limit;
1921   if (os::has_allocatable_memory_limit(&max_allocatable)) {
1922     result = MIN2(result, max_allocatable / MaxVirtMemFraction);
1923   }
1924   return result;
1925 }
1926 
1927 void Arguments::set_heap_size() {
1928   if (!FLAG_IS_DEFAULT(DefaultMaxRAMFraction)) {
1929     // Deprecated flag
1930     FLAG_SET_CMDLINE(uintx, MaxRAMFraction, DefaultMaxRAMFraction);
1931   }
1932 
1933   julong phys_mem =
1934     FLAG_IS_DEFAULT(MaxRAM) ? MIN2(os::physical_memory(), (julong)MaxRAM)
1935                             : (julong)MaxRAM;
1936 
1937   // Experimental support for CGroup memory limits
1938   if (UseCGroupMemoryLimitForHeap) {
1939     // This is a rough indicator that a CGroup limit may be in force
1940     // for this process
1941     const char* lim_file = "/sys/fs/cgroup/memory/memory.limit_in_bytes";
1942     FILE *fp = fopen(lim_file, "r");
1943     if (fp != NULL) {
1944       julong cgroup_max = 0;
1945       int ret = fscanf(fp, JULONG_FORMAT, &cgroup_max);
1946       if (ret == 1 && cgroup_max > 0) {
1947         // If unlimited, cgroup_max will be a very large, but unspecified
1948         // value, so use initial phys_mem as a limit
1949         if (PrintGCDetails && Verbose) {
1950           // Cannot use gclog_or_tty yet.
1951           tty->print_cr("Setting phys_mem to the min of cgroup limit ("
1952                         JULONG_FORMAT "MB) and initial phys_mem ("
1953                         JULONG_FORMAT "MB)", cgroup_max/M, phys_mem/M);
1954         }
1955         phys_mem = MIN2(cgroup_max, phys_mem);
1956       } else {
1957         warning("Unable to read/parse cgroup memory limit from %s: %s",
1958                 lim_file, errno != 0 ? strerror(errno) : "unknown error");
1959       }
1960       fclose(fp);
1961     } else {
1962       warning("Unable to open cgroup memory limit file %s (%s)", lim_file, strerror(errno));
1963     }
1964   }
1965 
1966   // If the maximum heap size has not been set with -Xmx,
1967   // then set it as fraction of the size of physical memory,
1968   // respecting the maximum and minimum sizes of the heap.
1969   if (FLAG_IS_DEFAULT(MaxHeapSize)) {
1970     julong reasonable_max = phys_mem / MaxRAMFraction;
1971 
1972     if (phys_mem <= MaxHeapSize * MinRAMFraction) {
1973       // Small physical memory, so use a minimum fraction of it for the heap
1974       reasonable_max = phys_mem / MinRAMFraction;
1975     } else {
1976       // Not-small physical memory, so require a heap at least
1977       // as large as MaxHeapSize
1978       reasonable_max = MAX2(reasonable_max, (julong)MaxHeapSize);
1979     }
1980     if (!FLAG_IS_DEFAULT(ErgoHeapSizeLimit) && ErgoHeapSizeLimit != 0) {
1981       // Limit the heap size to ErgoHeapSizeLimit
1982       reasonable_max = MIN2(reasonable_max, (julong)ErgoHeapSizeLimit);
1983     }
1984     if (UseCompressedOops) {
1985       // Limit the heap size to the maximum possible when using compressed oops
1986       julong max_coop_heap = (julong)max_heap_for_compressed_oops();
1987       if (HeapBaseMinAddress + MaxHeapSize < max_coop_heap) {
1988         // Heap should be above HeapBaseMinAddress to get zero based compressed oops
1989         // but it should be not less than default MaxHeapSize.
1990         max_coop_heap -= HeapBaseMinAddress;
1991       }
1992       reasonable_max = MIN2(reasonable_max, max_coop_heap);
1993     }
1994     reasonable_max = limit_by_allocatable_memory(reasonable_max);
1995 
1996     if (!FLAG_IS_DEFAULT(InitialHeapSize)) {
1997       // An initial heap size was specified on the command line,
1998       // so be sure that the maximum size is consistent.  Done
1999       // after call to limit_by_allocatable_memory because that
2000       // method might reduce the allocation size.
2001       reasonable_max = MAX2(reasonable_max, (julong)InitialHeapSize);
2002     }
2003 
2004     if (PrintGCDetails && Verbose) {
2005       // Cannot use gclog_or_tty yet.
2006       tty->print_cr("  Maximum heap size " SIZE_FORMAT, (size_t) reasonable_max);
2007     }
2008     FLAG_SET_ERGO(uintx, MaxHeapSize, (uintx)reasonable_max);
2009   }
2010 
2011   // If the minimum or initial heap_size have not been set or requested to be set
2012   // ergonomically, set them accordingly.
2013   if (InitialHeapSize == 0 || min_heap_size() == 0) {
2014     julong reasonable_minimum = (julong)(OldSize + NewSize);
2015 
2016     reasonable_minimum = MIN2(reasonable_minimum, (julong)MaxHeapSize);
2017 
2018     reasonable_minimum = limit_by_allocatable_memory(reasonable_minimum);
2019 
2020     if (InitialHeapSize == 0) {
2021       julong reasonable_initial = phys_mem / InitialRAMFraction;
2022 
2023       reasonable_initial = MAX3(reasonable_initial, reasonable_minimum, (julong)min_heap_size());
2024       reasonable_initial = MIN2(reasonable_initial, (julong)MaxHeapSize);
2025 
2026       reasonable_initial = limit_by_allocatable_memory(reasonable_initial);
2027 
2028       if (PrintGCDetails && Verbose) {
2029         // Cannot use gclog_or_tty yet.
2030         tty->print_cr("  Initial heap size " SIZE_FORMAT, (uintx)reasonable_initial);
2031       }
2032       FLAG_SET_ERGO(uintx, InitialHeapSize, (uintx)reasonable_initial);
2033     }
2034     // If the minimum heap size has not been set (via -Xms),
2035     // synchronize with InitialHeapSize to avoid errors with the default value.
2036     if (min_heap_size() == 0) {
2037       set_min_heap_size(MIN2((uintx)reasonable_minimum, InitialHeapSize));
2038       if (PrintGCDetails && Verbose) {
2039         // Cannot use gclog_or_tty yet.
2040         tty->print_cr("  Minimum heap size " SIZE_FORMAT, min_heap_size());
2041       }
2042     }
2043   }
2044 }
2045 
2046 // This must be called after ergonomics because we want bytecode rewriting
2047 // if the server compiler is used, or if UseSharedSpaces is disabled.
2048 void Arguments::set_bytecode_flags() {
2049   // Better not attempt to store into a read-only space.
2050   if (UseSharedSpaces) {
2051     FLAG_SET_DEFAULT(RewriteBytecodes, false);
2052     FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
2053   }
2054 
2055   if (!RewriteBytecodes) {
2056     FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
2057   }
2058 }
2059 
2060 // Aggressive optimization flags  -XX:+AggressiveOpts
2061 void Arguments::set_aggressive_opts_flags() {
2062 #ifdef COMPILER2
2063   if (AggressiveUnboxing) {
2064     if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
2065       FLAG_SET_DEFAULT(EliminateAutoBox, true);
2066     } else if (!EliminateAutoBox) {
2067       // warning("AggressiveUnboxing is disabled because EliminateAutoBox is disabled");
2068       AggressiveUnboxing = false;
2069     }
2070     if (FLAG_IS_DEFAULT(DoEscapeAnalysis)) {
2071       FLAG_SET_DEFAULT(DoEscapeAnalysis, true);
2072     } else if (!DoEscapeAnalysis) {
2073       // warning("AggressiveUnboxing is disabled because DoEscapeAnalysis is disabled");
2074       AggressiveUnboxing = false;
2075     }
2076   }
2077   if (AggressiveOpts || !FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
2078     if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
2079       FLAG_SET_DEFAULT(EliminateAutoBox, true);
2080     }
2081     if (FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
2082       FLAG_SET_DEFAULT(AutoBoxCacheMax, 20000);
2083     }
2084 
2085     // Feed the cache size setting into the JDK
2086     char buffer[1024];
2087     jio_snprintf(buffer, 1024, "java.lang.Integer.IntegerCache.high=" INTX_FORMAT, AutoBoxCacheMax);
2088     add_property(buffer);
2089   }
2090   if (AggressiveOpts && FLAG_IS_DEFAULT(BiasedLockingStartupDelay)) {
2091     FLAG_SET_DEFAULT(BiasedLockingStartupDelay, 500);
2092   }
2093 #endif
2094 
2095   if (AggressiveOpts) {
2096 // Sample flag setting code
2097 //    if (FLAG_IS_DEFAULT(EliminateZeroing)) {
2098 //      FLAG_SET_DEFAULT(EliminateZeroing, true);
2099 //    }
2100   }
2101 }
2102 
2103 //===========================================================================================================
2104 // Parsing of java.compiler property
2105 
2106 void Arguments::process_java_compiler_argument(char* arg) {
2107   // For backwards compatibility, Djava.compiler=NONE or ""
2108   // causes us to switch to -Xint mode UNLESS -Xdebug
2109   // is also specified.
2110   if (strlen(arg) == 0 || strcasecmp(arg, "NONE") == 0) {
2111     set_java_compiler(true);    // "-Djava.compiler[=...]" most recently seen.
2112   }
2113 }
2114 
2115 void Arguments::process_java_launcher_argument(const char* launcher, void* extra_info) {
2116   _sun_java_launcher = strdup(launcher);
2117   if (strcmp("gamma", _sun_java_launcher) == 0) {
2118     _created_by_gamma_launcher = true;
2119   }
2120 }
2121 
2122 bool Arguments::created_by_java_launcher() {
2123   assert(_sun_java_launcher != NULL, "property must have value");
2124   return strcmp(DEFAULT_JAVA_LAUNCHER, _sun_java_launcher) != 0;
2125 }
2126 
2127 bool Arguments::created_by_gamma_launcher() {
2128   return _created_by_gamma_launcher;
2129 }
2130 
2131 //===========================================================================================================
2132 // Parsing of main arguments
2133 
2134 bool Arguments::verify_interval(uintx val, uintx min,
2135                                 uintx max, const char* name) {
2136   // Returns true iff value is in the inclusive interval [min..max]
2137   // false, otherwise.
2138   if (val >= min && val <= max) {
2139     return true;
2140   }
2141   jio_fprintf(defaultStream::error_stream(),
2142               "%s of " UINTX_FORMAT " is invalid; must be between " UINTX_FORMAT
2143               " and " UINTX_FORMAT "\n",
2144               name, val, min, max);
2145   return false;
2146 }
2147 
2148 bool Arguments::verify_min_value(intx val, intx min, const char* name) {
2149   // Returns true if given value is at least specified min threshold
2150   // false, otherwise.
2151   if (val >= min ) {
2152       return true;
2153   }
2154   jio_fprintf(defaultStream::error_stream(),
2155               "%s of " INTX_FORMAT " is invalid; must be at least " INTX_FORMAT "\n",
2156               name, val, min);
2157   return false;
2158 }
2159 
2160 bool Arguments::verify_percentage(uintx value, const char* name) {
2161   if (is_percentage(value)) {
2162     return true;
2163   }
2164   jio_fprintf(defaultStream::error_stream(),
2165               "%s of " UINTX_FORMAT " is invalid; must be between 0 and 100\n",
2166               name, value);
2167   return false;
2168 }
2169 
2170 // check if do gclog rotation
2171 // +UseGCLogFileRotation is a must,
2172 // no gc log rotation when log file not supplied or
2173 // NumberOfGCLogFiles is 0
2174 void check_gclog_consistency() {
2175   if (UseGCLogFileRotation) {
2176     if ((Arguments::gc_log_filename() == NULL) || (NumberOfGCLogFiles == 0)) {
2177       jio_fprintf(defaultStream::output_stream(),
2178                   "To enable GC log rotation, use -Xloggc:<filename> -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=<num_of_files>\n"
2179                   "where num_of_file > 0\n"
2180                   "GC log rotation is turned off\n");
2181       UseGCLogFileRotation = false;
2182     }
2183   }
2184 
2185   if (UseGCLogFileRotation && (GCLogFileSize != 0) && (GCLogFileSize < 8*K)) {
2186     FLAG_SET_CMDLINE(uintx, GCLogFileSize, 8*K);
2187     jio_fprintf(defaultStream::output_stream(),
2188                 "GCLogFileSize changed to minimum 8K\n");
2189   }
2190 
2191   // Record more information about previous cycles for improved debugging pleasure
2192   if (FLAG_IS_DEFAULT(LogEventsBufferEntries)) {
2193     FLAG_SET_DEFAULT(LogEventsBufferEntries, 250);
2194   }
2195 
2196 #if INCLUDE_ALL_GCS
2197   if (AlwaysPreTouch || ShenandoahAlwaysPreTouch) {
2198     if (!FLAG_IS_DEFAULT(ShenandoahUncommitDelay)) {
2199       warning("AlwaysPreTouch is enabled, disabling ShenandoahUncommitDelay");
2200     }
2201     FLAG_SET_DEFAULT(ShenandoahUncommitDelay, max_uintx);
2202   }
2203 #endif
2204 }
2205 
2206 // This function is called for -Xloggc:<filename>, it can be used
2207 // to check if a given file name(or string) conforms to the following
2208 // specification:
2209 // A valid string only contains "[A-Z][a-z][0-9].-_%[p|t]"
2210 // %p and %t only allowed once. We only limit usage of filename not path
2211 bool is_filename_valid(const char *file_name) {
2212   const char* p = file_name;
2213   char file_sep = os::file_separator()[0];
2214   const char* cp;
2215   // skip prefix path
2216   for (cp = file_name; *cp != '\0'; cp++) {
2217     if (*cp == '/' || *cp == file_sep) {
2218       p = cp + 1;
2219     }
2220   }
2221 
2222   int count_p = 0;
2223   int count_t = 0;
2224   while (*p != '\0') {
2225     if ((*p >= '0' && *p <= '9') ||
2226         (*p >= 'A' && *p <= 'Z') ||
2227         (*p >= 'a' && *p <= 'z') ||
2228          *p == '-'               ||
2229          *p == '_'               ||
2230          *p == '.') {
2231        p++;
2232        continue;
2233     }
2234     if (*p == '%') {
2235       if(*(p + 1) == 'p') {
2236         p += 2;
2237         count_p ++;
2238         continue;
2239       }
2240       if (*(p + 1) == 't') {
2241         p += 2;
2242         count_t ++;
2243         continue;
2244       }
2245     }
2246     return false;
2247   }
2248   return count_p < 2 && count_t < 2;
2249 }
2250 
2251 bool Arguments::verify_MinHeapFreeRatio(FormatBuffer<80>& err_msg, uintx min_heap_free_ratio) {
2252   if (!is_percentage(min_heap_free_ratio)) {
2253     err_msg.print("MinHeapFreeRatio must have a value between 0 and 100");
2254     return false;
2255   }
2256   if (min_heap_free_ratio > MaxHeapFreeRatio) {
2257     err_msg.print("MinHeapFreeRatio (" UINTX_FORMAT ") must be less than or "
2258                   "equal to MaxHeapFreeRatio (" UINTX_FORMAT ")", min_heap_free_ratio,
2259                   MaxHeapFreeRatio);
2260     return false;
2261   }
2262   // This does not set the flag itself, but stores the value in a safe place for later usage.
2263   _min_heap_free_ratio = min_heap_free_ratio;
2264   return true;
2265 }
2266 
2267 bool Arguments::verify_MaxHeapFreeRatio(FormatBuffer<80>& err_msg, uintx max_heap_free_ratio) {
2268   if (!is_percentage(max_heap_free_ratio)) {
2269     err_msg.print("MaxHeapFreeRatio must have a value between 0 and 100");
2270     return false;
2271   }
2272   if (max_heap_free_ratio < MinHeapFreeRatio) {
2273     err_msg.print("MaxHeapFreeRatio (" UINTX_FORMAT ") must be greater than or "
2274                   "equal to MinHeapFreeRatio (" UINTX_FORMAT ")", max_heap_free_ratio,
2275                   MinHeapFreeRatio);
2276     return false;
2277   }
2278   // This does not set the flag itself, but stores the value in a safe place for later usage.
2279   _max_heap_free_ratio = max_heap_free_ratio;
2280   return true;
2281 }
2282 
2283 // Check consistency of GC selection
2284 bool Arguments::check_gc_consistency() {
2285   check_gclog_consistency();
2286   bool status = true;
2287   // Ensure that the user has not selected conflicting sets
2288   // of collectors. [Note: this check is merely a user convenience;
2289   // collectors over-ride each other so that only a non-conflicting
2290   // set is selected; however what the user gets is not what they
2291   // may have expected from the combination they asked for. It's
2292   // better to reduce user confusion by not allowing them to
2293   // select conflicting combinations.
2294   uint i = 0;
2295   if (UseSerialGC)                       i++;
2296   if (UseConcMarkSweepGC || UseParNewGC) i++;
2297   if (UseParallelGC || UseParallelOldGC) i++;
2298   if (UseG1GC)                           i++;
2299   if (UseShenandoahGC)                   i++;
2300   if (i > 1) {
2301     jio_fprintf(defaultStream::error_stream(),
2302                 "Conflicting collector combinations in option list; "
2303                 "please refer to the release notes for the combinations "
2304                 "allowed\n");
2305     status = false;
2306   }
2307   return status;
2308 }
2309 
2310 void Arguments::check_deprecated_gcs() {
2311   if (UseConcMarkSweepGC && !UseParNewGC) {
2312     warning("Using the DefNew young collector with the CMS collector is deprecated "
2313         "and will likely be removed in a future release");
2314   }
2315 
2316   if (UseParNewGC && !UseConcMarkSweepGC) {
2317     // !UseConcMarkSweepGC means that we are using serial old gc. Unfortunately we don't
2318     // set up UseSerialGC properly, so that can't be used in the check here.
2319     warning("Using the ParNew young collector with the Serial old collector is deprecated "
2320         "and will likely be removed in a future release");
2321   }
2322 
2323   if (CMSIncrementalMode) {
2324     warning("Using incremental CMS is deprecated and will likely be removed in a future release");
2325   }
2326 }
2327 
2328 void Arguments::check_deprecated_gc_flags() {
2329   if (FLAG_IS_CMDLINE(MaxGCMinorPauseMillis)) {
2330     warning("Using MaxGCMinorPauseMillis as minor pause goal is deprecated"
2331             "and will likely be removed in future release");
2332   }
2333   if (FLAG_IS_CMDLINE(DefaultMaxRAMFraction)) {
2334     warning("DefaultMaxRAMFraction is deprecated and will likely be removed in a future release. "
2335         "Use MaxRAMFraction instead.");
2336   }
2337   if (FLAG_IS_CMDLINE(UseCMSCompactAtFullCollection)) {
2338     warning("UseCMSCompactAtFullCollection is deprecated and will likely be removed in a future release.");
2339   }
2340   if (FLAG_IS_CMDLINE(CMSFullGCsBeforeCompaction)) {
2341     warning("CMSFullGCsBeforeCompaction is deprecated and will likely be removed in a future release.");
2342   }
2343   if (FLAG_IS_CMDLINE(UseCMSCollectionPassing)) {
2344     warning("UseCMSCollectionPassing is deprecated and will likely be removed in a future release.");
2345   }
2346 }
2347 
2348 // Check stack pages settings
2349 bool Arguments::check_stack_pages()
2350 {
2351   bool status = true;
2352   status = status && verify_min_value(StackYellowPages, 1, "StackYellowPages");
2353   status = status && verify_min_value(StackRedPages, 1, "StackRedPages");
2354   // greater stack shadow pages can't generate instruction to bang stack
2355   status = status && verify_interval(StackShadowPages, 1, 50, "StackShadowPages");
2356   return status;
2357 }
2358 
2359 // Check the consistency of vm_init_args
2360 bool Arguments::check_vm_args_consistency() {
2361   // Method for adding checks for flag consistency.
2362   // The intent is to warn the user of all possible conflicts,
2363   // before returning an error.
2364   // Note: Needs platform-dependent factoring.
2365   bool status = true;
2366 
2367   // Allow both -XX:-UseStackBanging and -XX:-UseBoundThreads in non-product
2368   // builds so the cost of stack banging can be measured.
2369 #if (defined(PRODUCT) && defined(SOLARIS))
2370   if (!UseBoundThreads && !UseStackBanging) {
2371     jio_fprintf(defaultStream::error_stream(),
2372                 "-UseStackBanging conflicts with -UseBoundThreads\n");
2373 
2374      status = false;
2375   }
2376 #endif
2377 
2378   if (TLABRefillWasteFraction == 0) {
2379     jio_fprintf(defaultStream::error_stream(),
2380                 "TLABRefillWasteFraction should be a denominator, "
2381                 "not " SIZE_FORMAT "\n",
2382                 TLABRefillWasteFraction);
2383     status = false;
2384   }
2385 
2386   status = status && verify_interval(AdaptiveSizePolicyWeight, 0, 100,
2387                               "AdaptiveSizePolicyWeight");
2388   status = status && verify_percentage(ThresholdTolerance, "ThresholdTolerance");
2389 
2390   // Divide by bucket size to prevent a large size from causing rollover when
2391   // calculating amount of memory needed to be allocated for the String table.
2392   status = status && verify_interval(StringTableSize, minimumStringTableSize,
2393     (max_uintx / StringTable::bucket_size()), "StringTable size");
2394 
2395   status = status && verify_interval(SymbolTableSize, minimumSymbolTableSize,
2396     (max_uintx / SymbolTable::bucket_size()), "SymbolTable size");
2397 
2398   {
2399     // Using "else if" below to avoid printing two error messages if min > max.
2400     // This will also prevent us from reporting both min>100 and max>100 at the
2401     // same time, but that is less annoying than printing two identical errors IMHO.
2402     FormatBuffer<80> err_msg("%s","");
2403     if (!verify_MinHeapFreeRatio(err_msg, MinHeapFreeRatio)) {
2404       jio_fprintf(defaultStream::error_stream(), "%s\n", err_msg.buffer());
2405       status = false;
2406     } else if (!verify_MaxHeapFreeRatio(err_msg, MaxHeapFreeRatio)) {
2407       jio_fprintf(defaultStream::error_stream(), "%s\n", err_msg.buffer());
2408       status = false;
2409     }
2410   }
2411 
2412   // Min/MaxMetaspaceFreeRatio
2413   status = status && verify_percentage(MinMetaspaceFreeRatio, "MinMetaspaceFreeRatio");
2414   status = status && verify_percentage(MaxMetaspaceFreeRatio, "MaxMetaspaceFreeRatio");
2415 
2416   if (MinMetaspaceFreeRatio > MaxMetaspaceFreeRatio) {
2417     jio_fprintf(defaultStream::error_stream(),
2418                 "MinMetaspaceFreeRatio (%s" UINTX_FORMAT ") must be less than or "
2419                 "equal to MaxMetaspaceFreeRatio (%s" UINTX_FORMAT ")\n",
2420                 FLAG_IS_DEFAULT(MinMetaspaceFreeRatio) ? "Default: " : "",
2421                 MinMetaspaceFreeRatio,
2422                 FLAG_IS_DEFAULT(MaxMetaspaceFreeRatio) ? "Default: " : "",
2423                 MaxMetaspaceFreeRatio);
2424     status = false;
2425   }
2426 
2427   // Trying to keep 100% free is not practical
2428   MinMetaspaceFreeRatio = MIN2(MinMetaspaceFreeRatio, (uintx) 99);
2429 
2430   if (FullGCALot && FLAG_IS_DEFAULT(MarkSweepAlwaysCompactCount)) {
2431     MarkSweepAlwaysCompactCount = 1;  // Move objects every gc.
2432   }
2433 
2434   if (UseParallelOldGC && ParallelOldGCSplitALot) {
2435     // Settings to encourage splitting.
2436     if (!FLAG_IS_CMDLINE(NewRatio)) {
2437       FLAG_SET_CMDLINE(uintx, NewRatio, 2);
2438     }
2439     if (!FLAG_IS_CMDLINE(ScavengeBeforeFullGC)) {
2440       FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
2441     }
2442   }
2443 
2444   status = status && verify_percentage(GCHeapFreeLimit, "GCHeapFreeLimit");
2445   status = status && verify_percentage(GCTimeLimit, "GCTimeLimit");
2446   if (GCTimeLimit == 100) {
2447     // Turn off gc-overhead-limit-exceeded checks
2448     FLAG_SET_DEFAULT(UseGCOverheadLimit, false);
2449   }
2450 
2451   status = status && check_gc_consistency();
2452   status = status && check_stack_pages();
2453 
2454   if (CMSIncrementalMode) {
2455     if (!UseConcMarkSweepGC) {
2456       jio_fprintf(defaultStream::error_stream(),
2457                   "error:  invalid argument combination.\n"
2458                   "The CMS collector (-XX:+UseConcMarkSweepGC) must be "
2459                   "selected in order\nto use CMSIncrementalMode.\n");
2460       status = false;
2461     } else {
2462       status = status && verify_percentage(CMSIncrementalDutyCycle,
2463                                   "CMSIncrementalDutyCycle");
2464       status = status && verify_percentage(CMSIncrementalDutyCycleMin,
2465                                   "CMSIncrementalDutyCycleMin");
2466       status = status && verify_percentage(CMSIncrementalSafetyFactor,
2467                                   "CMSIncrementalSafetyFactor");
2468       status = status && verify_percentage(CMSIncrementalOffset,
2469                                   "CMSIncrementalOffset");
2470       status = status && verify_percentage(CMSExpAvgFactor,
2471                                   "CMSExpAvgFactor");
2472       // If it was not set on the command line, set
2473       // CMSInitiatingOccupancyFraction to 1 so icms can initiate cycles early.
2474       if (CMSInitiatingOccupancyFraction < 0) {
2475         FLAG_SET_DEFAULT(CMSInitiatingOccupancyFraction, 1);
2476       }
2477     }
2478   }
2479 
2480   // CMS space iteration, which FLSVerifyAllHeapreferences entails,
2481   // insists that we hold the requisite locks so that the iteration is
2482   // MT-safe. For the verification at start-up and shut-down, we don't
2483   // yet have a good way of acquiring and releasing these locks,
2484   // which are not visible at the CollectedHeap level. We want to
2485   // be able to acquire these locks and then do the iteration rather
2486   // than just disable the lock verification. This will be fixed under
2487   // bug 4788986.
2488   if (UseConcMarkSweepGC && FLSVerifyAllHeapReferences) {
2489     if (VerifyDuringStartup) {
2490       warning("Heap verification at start-up disabled "
2491               "(due to current incompatibility with FLSVerifyAllHeapReferences)");
2492       VerifyDuringStartup = false; // Disable verification at start-up
2493     }
2494 
2495     if (VerifyBeforeExit) {
2496       warning("Heap verification at shutdown disabled "
2497               "(due to current incompatibility with FLSVerifyAllHeapReferences)");
2498       VerifyBeforeExit = false; // Disable verification at shutdown
2499     }
2500   }
2501 
2502   // Note: only executed in non-PRODUCT mode
2503   if (!UseAsyncConcMarkSweepGC &&
2504       (ExplicitGCInvokesConcurrent ||
2505        ExplicitGCInvokesConcurrentAndUnloadsClasses)) {
2506     jio_fprintf(defaultStream::error_stream(),
2507                 "error: +ExplicitGCInvokesConcurrent[AndUnloadsClasses] conflicts"
2508                 " with -UseAsyncConcMarkSweepGC");
2509     status = false;
2510   }
2511 
2512   status = status && verify_min_value(ParGCArrayScanChunk, 1, "ParGCArrayScanChunk");
2513 
2514 #if INCLUDE_ALL_GCS
2515   if (UseG1GC) {
2516     status = status && verify_percentage(G1NewSizePercent, "G1NewSizePercent");
2517     status = status && verify_percentage(G1MaxNewSizePercent, "G1MaxNewSizePercent");
2518     status = status && verify_interval(G1NewSizePercent, 0, G1MaxNewSizePercent, "G1NewSizePercent");
2519 
2520     status = status && verify_percentage(InitiatingHeapOccupancyPercent,
2521                                          "InitiatingHeapOccupancyPercent");
2522     status = status && verify_min_value(G1RefProcDrainInterval, 1,
2523                                         "G1RefProcDrainInterval");
2524     status = status && verify_min_value((intx)G1ConcMarkStepDurationMillis, 1,
2525                                         "G1ConcMarkStepDurationMillis");
2526     status = status && verify_interval(G1ConcRSHotCardLimit, 0, max_jubyte,
2527                                        "G1ConcRSHotCardLimit");
2528     status = status && verify_interval(G1ConcRSLogCacheSize, 0, 27,
2529                                        "G1ConcRSLogCacheSize");
2530     status = status && verify_interval(StringDeduplicationAgeThreshold, 1, markOopDesc::max_age,
2531                                        "StringDeduplicationAgeThreshold");
2532   }
2533   if (UseConcMarkSweepGC) {
2534     status = status && verify_min_value(CMSOldPLABNumRefills, 1, "CMSOldPLABNumRefills");
2535     status = status && verify_min_value(CMSOldPLABToleranceFactor, 1, "CMSOldPLABToleranceFactor");
2536     status = status && verify_min_value(CMSOldPLABMax, 1, "CMSOldPLABMax");
2537     status = status && verify_interval(CMSOldPLABMin, 1, CMSOldPLABMax, "CMSOldPLABMin");
2538 
2539     status = status && verify_min_value(CMSYoungGenPerWorker, 1, "CMSYoungGenPerWorker");
2540 
2541     status = status && verify_min_value(CMSSamplingGrain, 1, "CMSSamplingGrain");
2542     status = status && verify_interval(CMS_SweepWeight, 0, 100, "CMS_SweepWeight");
2543     status = status && verify_interval(CMS_FLSWeight, 0, 100, "CMS_FLSWeight");
2544 
2545     status = status && verify_interval(FLSCoalescePolicy, 0, 4, "FLSCoalescePolicy");
2546 
2547     status = status && verify_min_value(CMSRescanMultiple, 1, "CMSRescanMultiple");
2548     status = status && verify_min_value(CMSConcMarkMultiple, 1, "CMSConcMarkMultiple");
2549 
2550     status = status && verify_interval(CMSPrecleanIter, 0, 9, "CMSPrecleanIter");
2551     status = status && verify_min_value(CMSPrecleanDenominator, 1, "CMSPrecleanDenominator");
2552     status = status && verify_interval(CMSPrecleanNumerator, 0, CMSPrecleanDenominator - 1, "CMSPrecleanNumerator");
2553 
2554     status = status && verify_percentage(CMSBootstrapOccupancy, "CMSBootstrapOccupancy");
2555 
2556     status = status && verify_min_value(CMSPrecleanThreshold, 100, "CMSPrecleanThreshold");
2557 
2558     status = status && verify_percentage(CMSScheduleRemarkEdenPenetration, "CMSScheduleRemarkEdenPenetration");
2559     status = status && verify_min_value(CMSScheduleRemarkSamplingRatio, 1, "CMSScheduleRemarkSamplingRatio");
2560     status = status && verify_min_value(CMSBitMapYieldQuantum, 1, "CMSBitMapYieldQuantum");
2561     status = status && verify_percentage(CMSTriggerRatio, "CMSTriggerRatio");
2562     status = status && verify_percentage(CMSIsTooFullPercentage, "CMSIsTooFullPercentage");
2563   }
2564 
2565   if (UseParallelGC || UseParallelOldGC) {
2566     status = status && verify_interval(ParallelOldDeadWoodLimiterMean, 0, 100, "ParallelOldDeadWoodLimiterMean");
2567     status = status && verify_interval(ParallelOldDeadWoodLimiterStdDev, 0, 100, "ParallelOldDeadWoodLimiterStdDev");
2568 
2569     status = status && verify_percentage(YoungGenerationSizeIncrement, "YoungGenerationSizeIncrement");
2570     status = status && verify_percentage(TenuredGenerationSizeIncrement, "TenuredGenerationSizeIncrement");
2571 
2572     status = status && verify_min_value(YoungGenerationSizeSupplementDecay, 1, "YoungGenerationSizeSupplementDecay");
2573     status = status && verify_min_value(TenuredGenerationSizeSupplementDecay, 1, "TenuredGenerationSizeSupplementDecay");
2574 
2575     status = status && verify_min_value(ParGCCardsPerStrideChunk, 1, "ParGCCardsPerStrideChunk");
2576 
2577     status = status && verify_min_value(ParallelOldGCSplitInterval, 0, "ParallelOldGCSplitInterval");
2578   }
2579 #endif // INCLUDE_ALL_GCS
2580 
2581   status = status && verify_interval(RefDiscoveryPolicy,
2582                                      ReferenceProcessor::DiscoveryPolicyMin,
2583                                      ReferenceProcessor::DiscoveryPolicyMax,
2584                                      "RefDiscoveryPolicy");
2585 
2586   // Limit the lower bound of this flag to 1 as it is used in a division
2587   // expression.
2588   status = status && verify_interval(TLABWasteTargetPercent,
2589                                      1, 100, "TLABWasteTargetPercent");
2590 
2591   status = status && verify_object_alignment();
2592 
2593   status = status && verify_interval(CompressedClassSpaceSize, 1*M, 3*G,
2594                                       "CompressedClassSpaceSize");
2595 
2596   status = status && verify_interval(MarkStackSizeMax,
2597                                   1, (max_jint - 1), "MarkStackSizeMax");
2598   status = status && verify_interval(NUMAChunkResizeWeight, 0, 100, "NUMAChunkResizeWeight");
2599 
2600   status = status && verify_min_value(LogEventsBufferEntries, 1, "LogEventsBufferEntries");
2601 
2602   status = status && verify_min_value(HeapSizePerGCThread, (uintx) os::vm_page_size(), "HeapSizePerGCThread");
2603 
2604   status = status && verify_min_value(GCTaskTimeStampEntries, 1, "GCTaskTimeStampEntries");
2605 
2606   status = status && verify_percentage(ParallelGCBufferWastePct, "ParallelGCBufferWastePct");
2607   status = status && verify_interval(TargetPLABWastePct, 1, 100, "TargetPLABWastePct");
2608 
2609   status = status && verify_min_value(ParGCStridesPerThread, 1, "ParGCStridesPerThread");
2610 
2611   status = status && verify_min_value(MinRAMFraction, 1, "MinRAMFraction");
2612   status = status && verify_min_value(InitialRAMFraction, 1, "InitialRAMFraction");
2613   status = status && verify_min_value(MaxRAMFraction, 1, "MaxRAMFraction");
2614   status = status && verify_min_value(DefaultMaxRAMFraction, 1, "DefaultMaxRAMFraction");
2615 
2616   status = status && verify_interval(AdaptiveTimeWeight, 0, 100, "AdaptiveTimeWeight");
2617   status = status && verify_min_value(AdaptiveSizeDecrementScaleFactor, 1, "AdaptiveSizeDecrementScaleFactor");
2618 
2619   status = status && verify_interval(TLABAllocationWeight, 0, 100, "TLABAllocationWeight");
2620   status = status && verify_min_value(MinTLABSize, 1, "MinTLABSize");
2621   status = status && verify_min_value(TLABRefillWasteFraction, 1, "TLABRefillWasteFraction");
2622 
2623   status = status && verify_percentage(YoungGenerationSizeSupplement, "YoungGenerationSizeSupplement");
2624   status = status && verify_percentage(TenuredGenerationSizeSupplement, "TenuredGenerationSizeSupplement");
2625 
2626   // the "age" field in the oop header is 4 bits; do not want to pull in markOop.hpp
2627   // just for that, so hardcode here.
2628   status = status && verify_interval(MaxTenuringThreshold, 0, 15, "MaxTenuringThreshold");
2629   status = status && verify_interval(InitialTenuringThreshold, 0, MaxTenuringThreshold, "MaxTenuringThreshold");
2630   status = status && verify_percentage(TargetSurvivorRatio, "TargetSurvivorRatio");
2631   status = status && verify_percentage(MarkSweepDeadRatio, "MarkSweepDeadRatio");
2632 
2633   status = status && verify_min_value(MarkSweepAlwaysCompactCount, 1, "MarkSweepAlwaysCompactCount");
2634 #ifdef COMPILER1
2635   status = status && verify_min_value(ValueMapInitialSize, 1, "ValueMapInitialSize");
2636 #endif
2637 
2638   if (PrintNMTStatistics) {
2639 #if INCLUDE_NMT
2640     if (MemTracker::tracking_level() == NMT_off) {
2641 #endif // INCLUDE_NMT
2642       warning("PrintNMTStatistics is disabled, because native memory tracking is not enabled");
2643       PrintNMTStatistics = false;
2644 #if INCLUDE_NMT
2645     }
2646 #endif
2647   }
2648 
2649   // Need to limit the extent of the padding to reasonable size.
2650   // 8K is well beyond the reasonable HW cache line size, even with the
2651   // aggressive prefetching, while still leaving the room for segregating
2652   // among the distinct pages.
2653   if (ContendedPaddingWidth < 0 || ContendedPaddingWidth > 8192) {
2654     jio_fprintf(defaultStream::error_stream(),
2655                 "ContendedPaddingWidth=" INTX_FORMAT " must be in between %d and %d\n",
2656                 ContendedPaddingWidth, 0, 8192);
2657     status = false;
2658   }
2659 
2660   // Need to enforce the padding not to break the existing field alignments.
2661   // It is sufficient to check against the largest type size.
2662   if ((ContendedPaddingWidth % BytesPerLong) != 0) {
2663     jio_fprintf(defaultStream::error_stream(),
2664                 "ContendedPaddingWidth=" INTX_FORMAT " must be a multiple of %d\n",
2665                 ContendedPaddingWidth, BytesPerLong);
2666     status = false;
2667   }
2668 
2669   // Check lower bounds of the code cache
2670   // Template Interpreter code is approximately 3X larger in debug builds.
2671   uint min_code_cache_size = (CodeCacheMinimumUseSpace DEBUG_ONLY(* 3)) + CodeCacheMinimumFreeSpace;
2672   if (InitialCodeCacheSize < (uintx)os::vm_page_size()) {
2673     jio_fprintf(defaultStream::error_stream(),
2674                 "Invalid InitialCodeCacheSize=%dK. Must be at least %dK.\n", InitialCodeCacheSize/K,
2675                 os::vm_page_size()/K);
2676     status = false;
2677   } else if (ReservedCodeCacheSize < InitialCodeCacheSize) {
2678     jio_fprintf(defaultStream::error_stream(),
2679                 "Invalid ReservedCodeCacheSize: %dK. Must be at least InitialCodeCacheSize=%dK.\n",
2680                 ReservedCodeCacheSize/K, InitialCodeCacheSize/K);
2681     status = false;
2682   } else if (ReservedCodeCacheSize < min_code_cache_size) {
2683     jio_fprintf(defaultStream::error_stream(),
2684                 "Invalid ReservedCodeCacheSize=%dK. Must be at least %uK.\n", ReservedCodeCacheSize/K,
2685                 min_code_cache_size/K);
2686     status = false;
2687   } else if (ReservedCodeCacheSize > CODE_CACHE_SIZE_LIMIT) {
2688     // Code cache size larger than CODE_CACHE_SIZE_LIMIT is not supported.
2689     jio_fprintf(defaultStream::error_stream(),
2690                 "Invalid ReservedCodeCacheSize=%dM. Must be at most %uM.\n", ReservedCodeCacheSize/M,
2691                 CODE_CACHE_SIZE_LIMIT/M);
2692     status = false;
2693   }
2694 
2695   status &= verify_interval(NmethodSweepFraction, 1, ReservedCodeCacheSize/K, "NmethodSweepFraction");
2696   status &= verify_interval(NmethodSweepActivity, 0, 2000, "NmethodSweepActivity");
2697 
2698   if (!FLAG_IS_DEFAULT(CICompilerCount) && !FLAG_IS_DEFAULT(CICompilerCountPerCPU) && CICompilerCountPerCPU) {
2699     warning("The VM option CICompilerCountPerCPU overrides CICompilerCount.");
2700   }
2701 
2702 #ifdef COMPILER1
2703   status &= verify_interval(SafepointPollOffset, 0, os::vm_page_size() - BytesPerWord, "SafepointPollOffset");
2704 #endif
2705 
2706   int min_number_of_compiler_threads = get_min_number_of_compiler_threads();
2707   // The default CICompilerCount's value is CI_COMPILER_COUNT.
2708   assert(min_number_of_compiler_threads <= CI_COMPILER_COUNT, "minimum should be less or equal default number");
2709   // Check the minimum number of compiler threads
2710   status &=verify_min_value(CICompilerCount, min_number_of_compiler_threads, "CICompilerCount");
2711 
2712   return status;
2713 }
2714 
2715 bool Arguments::is_bad_option(const JavaVMOption* option, jboolean ignore,
2716   const char* option_type) {
2717   if (ignore) return false;
2718 
2719   const char* spacer = " ";
2720   if (option_type == NULL) {
2721     option_type = ++spacer; // Set both to the empty string.
2722   }
2723 
2724   if (os::obsolete_option(option)) {
2725     jio_fprintf(defaultStream::error_stream(),
2726                 "Obsolete %s%soption: %s\n", option_type, spacer,
2727       option->optionString);
2728     return false;
2729   } else {
2730     jio_fprintf(defaultStream::error_stream(),
2731                 "Unrecognized %s%soption: %s\n", option_type, spacer,
2732       option->optionString);
2733     return true;
2734   }
2735 }
2736 
2737 static const char* user_assertion_options[] = {
2738   "-da", "-ea", "-disableassertions", "-enableassertions", 0
2739 };
2740 
2741 static const char* system_assertion_options[] = {
2742   "-dsa", "-esa", "-disablesystemassertions", "-enablesystemassertions", 0
2743 };
2744 
2745 // Return true if any of the strings in null-terminated array 'names' matches.
2746 // If tail_allowed is true, then the tail must begin with a colon; otherwise,
2747 // the option must match exactly.
2748 static bool match_option(const JavaVMOption* option, const char** names, const char** tail,
2749   bool tail_allowed) {
2750   for (/* empty */; *names != NULL; ++names) {
2751     if (match_option(option, *names, tail)) {
2752       if (**tail == '\0' || tail_allowed && **tail == ':') {
2753         return true;
2754       }
2755     }
2756   }
2757   return false;
2758 }
2759 
2760 bool Arguments::parse_uintx(const char* value,
2761                             uintx* uintx_arg,
2762                             uintx min_size) {
2763 
2764   // Check the sign first since atomull() parses only unsigned values.
2765   bool value_is_positive = !(*value == '-');
2766 
2767   if (value_is_positive) {
2768     julong n;
2769     bool good_return = atomull(value, &n);
2770     if (good_return) {
2771       bool above_minimum = n >= min_size;
2772       bool value_is_too_large = n > max_uintx;
2773 
2774       if (above_minimum && !value_is_too_large) {
2775         *uintx_arg = n;
2776         return true;
2777       }
2778     }
2779   }
2780   return false;
2781 }
2782 
2783 Arguments::ArgsRange Arguments::parse_memory_size(const char* s,
2784                                                   julong* long_arg,
2785                                                   julong min_size) {
2786   if (!atomull(s, long_arg)) return arg_unreadable;
2787   return check_memory_size(*long_arg, min_size);
2788 }
2789 
2790 // Parse JavaVMInitArgs structure
2791 
2792 jint Arguments::parse_vm_init_args(const JavaVMInitArgs* args) {
2793   // For components of the system classpath.
2794   SysClassPath scp(Arguments::get_sysclasspath());
2795   bool scp_assembly_required = false;
2796 
2797   // Save default settings for some mode flags
2798   Arguments::_AlwaysCompileLoopMethods = AlwaysCompileLoopMethods;
2799   Arguments::_UseOnStackReplacement    = UseOnStackReplacement;
2800   Arguments::_ClipInlining             = ClipInlining;
2801   Arguments::_BackgroundCompilation    = BackgroundCompilation;
2802 
2803   // Setup flags for mixed which is the default
2804   set_mode_flags(_mixed);
2805 
2806   // Parse JAVA_TOOL_OPTIONS environment variable (if present)
2807   jint result = parse_java_tool_options_environment_variable(&scp, &scp_assembly_required);
2808   if (result != JNI_OK) {
2809     return result;
2810   }
2811 
2812   // Parse JavaVMInitArgs structure passed in
2813   result = parse_each_vm_init_arg(args, &scp, &scp_assembly_required, Flag::COMMAND_LINE);
2814   if (result != JNI_OK) {
2815     return result;
2816   }
2817 
2818   // Parse _JAVA_OPTIONS environment variable (if present) (mimics classic VM)
2819   result = parse_java_options_environment_variable(&scp, &scp_assembly_required);
2820   if (result != JNI_OK) {
2821     return result;
2822   }
2823 
2824   // Do final processing now that all arguments have been parsed
2825   result = finalize_vm_init_args(&scp, scp_assembly_required);
2826   if (result != JNI_OK) {
2827     return result;
2828   }
2829 
2830   return JNI_OK;
2831 }
2832 
2833 // Checks if name in command-line argument -agent{lib,path}:name[=options]
2834 // represents a valid HPROF of JDWP agent.  is_path==true denotes that we
2835 // are dealing with -agentpath (case where name is a path), otherwise with
2836 // -agentlib
2837 bool valid_hprof_or_jdwp_agent(char *name, bool is_path) {
2838   char *_name;
2839   const char *_hprof = "hprof", *_jdwp = "jdwp";
2840   size_t _len_hprof, _len_jdwp, _len_prefix;
2841 
2842   if (is_path) {
2843     if ((_name = strrchr(name, (int) *os::file_separator())) == NULL) {
2844       return false;
2845     }
2846 
2847     _name++;  // skip past last path separator
2848     _len_prefix = strlen(JNI_LIB_PREFIX);
2849 
2850     if (strncmp(_name, JNI_LIB_PREFIX, _len_prefix) != 0) {
2851       return false;
2852     }
2853 
2854     _name += _len_prefix;
2855     _len_hprof = strlen(_hprof);
2856     _len_jdwp = strlen(_jdwp);
2857 
2858     if (strncmp(_name, _hprof, _len_hprof) == 0) {
2859       _name += _len_hprof;
2860     }
2861     else if (strncmp(_name, _jdwp, _len_jdwp) == 0) {
2862       _name += _len_jdwp;
2863     }
2864     else {
2865       return false;
2866     }
2867 
2868     if (strcmp(_name, JNI_LIB_SUFFIX) != 0) {
2869       return false;
2870     }
2871 
2872     return true;
2873   }
2874 
2875   if (strcmp(name, _hprof) == 0 || strcmp(name, _jdwp) == 0) {
2876     return true;
2877   }
2878 
2879   return false;
2880 }
2881 
2882 jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args,
2883                                        SysClassPath* scp_p,
2884                                        bool* scp_assembly_required_p,
2885                                        Flag::Flags origin) {
2886   // Remaining part of option string
2887   const char* tail;
2888 
2889   // iterate over arguments
2890   for (int index = 0; index < args->nOptions; index++) {
2891     bool is_absolute_path = false;  // for -agentpath vs -agentlib
2892 
2893     const JavaVMOption* option = args->options + index;
2894 
2895     if (!match_option(option, "-Djava.class.path", &tail) &&
2896         !match_option(option, "-Dsun.java.command", &tail) &&
2897         !match_option(option, "-Dsun.java.launcher", &tail)) {
2898 
2899         // add all jvm options to the jvm_args string. This string
2900         // is used later to set the java.vm.args PerfData string constant.
2901         // the -Djava.class.path and the -Dsun.java.command options are
2902         // omitted from jvm_args string as each have their own PerfData
2903         // string constant object.
2904         build_jvm_args(option->optionString);
2905     }
2906 
2907     // -verbose:[class/gc/jni]
2908     if (match_option(option, "-verbose", &tail)) {
2909       if (!strcmp(tail, ":class") || !strcmp(tail, "")) {
2910         FLAG_SET_CMDLINE(bool, TraceClassLoading, true);
2911         FLAG_SET_CMDLINE(bool, TraceClassUnloading, true);
2912       } else if (!strcmp(tail, ":gc")) {
2913         FLAG_SET_CMDLINE(bool, PrintGC, true);
2914       } else if (!strcmp(tail, ":jni")) {
2915         FLAG_SET_CMDLINE(bool, PrintJNIResolving, true);
2916       }
2917     // -da / -ea / -disableassertions / -enableassertions
2918     // These accept an optional class/package name separated by a colon, e.g.,
2919     // -da:java.lang.Thread.
2920     } else if (match_option(option, user_assertion_options, &tail, true)) {
2921       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2922       if (*tail == '\0') {
2923         JavaAssertions::setUserClassDefault(enable);
2924       } else {
2925         assert(*tail == ':', "bogus match by match_option()");
2926         JavaAssertions::addOption(tail + 1, enable);
2927       }
2928     // -dsa / -esa / -disablesystemassertions / -enablesystemassertions
2929     } else if (match_option(option, system_assertion_options, &tail, false)) {
2930       bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
2931       JavaAssertions::setSystemClassDefault(enable);
2932     // -bootclasspath:
2933     } else if (match_option(option, "-Xbootclasspath:", &tail)) {
2934       scp_p->reset_path(tail);
2935       *scp_assembly_required_p = true;
2936     // -bootclasspath/a:
2937     } else if (match_option(option, "-Xbootclasspath/a:", &tail)) {
2938       scp_p->add_suffix(tail);
2939       *scp_assembly_required_p = true;
2940     // -bootclasspath/p:
2941     } else if (match_option(option, "-Xbootclasspath/p:", &tail)) {
2942       scp_p->add_prefix(tail);
2943       *scp_assembly_required_p = true;
2944     // -Xrun
2945     } else if (match_option(option, "-Xrun", &tail)) {
2946       if (tail != NULL) {
2947         const char* pos = strchr(tail, ':');
2948         size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
2949         char* name = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len + 1, mtInternal), tail, len);
2950         name[len] = '\0';
2951 
2952         char *options = NULL;
2953         if(pos != NULL) {
2954           size_t len2 = strlen(pos+1) + 1; // options start after ':'.  Final zero must be copied.
2955           options = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len2, mtInternal), pos+1, len2);
2956         }
2957 #if !INCLUDE_JVMTI
2958         if ((strcmp(name, "hprof") == 0) || (strcmp(name, "jdwp") == 0)) {
2959           jio_fprintf(defaultStream::error_stream(),
2960             "Profiling and debugging agents are not supported in this VM\n");
2961           return JNI_ERR;
2962         }
2963 #endif // !INCLUDE_JVMTI
2964         add_init_library(name, options);
2965       }
2966     // -agentlib and -agentpath
2967     } else if (match_option(option, "-agentlib:", &tail) ||
2968           (is_absolute_path = match_option(option, "-agentpath:", &tail))) {
2969       if(tail != NULL) {
2970         const char* pos = strchr(tail, '=');
2971         size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
2972         char* name = strncpy(NEW_C_HEAP_ARRAY(char, len + 1, mtInternal), tail, len);
2973         name[len] = '\0';
2974 
2975         char *options = NULL;
2976         if(pos != NULL) {
2977           size_t length = strlen(pos + 1) + 1;
2978           options = NEW_C_HEAP_ARRAY(char, length, mtInternal);
2979           jio_snprintf(options, length, "%s", pos + 1);
2980         }
2981 #if !INCLUDE_JVMTI
2982         if (valid_hprof_or_jdwp_agent(name, is_absolute_path)) {
2983           jio_fprintf(defaultStream::error_stream(),
2984             "Profiling and debugging agents are not supported in this VM\n");
2985           return JNI_ERR;
2986         }
2987 #endif // !INCLUDE_JVMTI
2988         add_init_agent(name, options, is_absolute_path);
2989       }
2990     // -javaagent
2991     } else if (match_option(option, "-javaagent:", &tail)) {
2992 #if !INCLUDE_JVMTI
2993       jio_fprintf(defaultStream::error_stream(),
2994         "Instrumentation agents are not supported in this VM\n");
2995       return JNI_ERR;
2996 #else
2997       if(tail != NULL) {
2998         size_t length = strlen(tail) + 1;
2999         char *options = NEW_C_HEAP_ARRAY(char, length, mtInternal);
3000         jio_snprintf(options, length, "%s", tail);
3001         add_init_agent("instrument", options, false);
3002       }
3003 #endif // !INCLUDE_JVMTI
3004     // -Xnoclassgc
3005     } else if (match_option(option, "-Xnoclassgc", &tail)) {
3006       FLAG_SET_CMDLINE(bool, ClassUnloading, false);
3007     // -Xincgc: i-CMS
3008     } else if (match_option(option, "-Xincgc", &tail)) {
3009       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, true);
3010       FLAG_SET_CMDLINE(bool, CMSIncrementalMode, true);
3011     // -Xnoincgc: no i-CMS
3012     } else if (match_option(option, "-Xnoincgc", &tail)) {
3013       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, false);
3014       FLAG_SET_CMDLINE(bool, CMSIncrementalMode, false);
3015     // -Xconcgc
3016     } else if (match_option(option, "-Xconcgc", &tail)) {
3017       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, true);
3018     // -Xnoconcgc
3019     } else if (match_option(option, "-Xnoconcgc", &tail)) {
3020       FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, false);
3021     // -Xbatch
3022     } else if (match_option(option, "-Xbatch", &tail)) {
3023       FLAG_SET_CMDLINE(bool, BackgroundCompilation, false);
3024     // -Xmn for compatibility with other JVM vendors
3025     } else if (match_option(option, "-Xmn", &tail)) {
3026       julong long_initial_young_size = 0;
3027       ArgsRange errcode = parse_memory_size(tail, &long_initial_young_size, 1);
3028       if (errcode != arg_in_range) {
3029         jio_fprintf(defaultStream::error_stream(),
3030                     "Invalid initial young generation size: %s\n", option->optionString);
3031         describe_range_error(errcode);
3032         return JNI_EINVAL;
3033       }
3034       FLAG_SET_CMDLINE(uintx, MaxNewSize, (uintx)long_initial_young_size);
3035       FLAG_SET_CMDLINE(uintx, NewSize, (uintx)long_initial_young_size);
3036     // -Xms
3037     } else if (match_option(option, "-Xms", &tail)) {
3038       julong long_initial_heap_size = 0;
3039       // an initial heap size of 0 means automatically determine
3040       ArgsRange errcode = parse_memory_size(tail, &long_initial_heap_size, 0);
3041       if (errcode != arg_in_range) {
3042         jio_fprintf(defaultStream::error_stream(),
3043                     "Invalid initial heap size: %s\n", option->optionString);
3044         describe_range_error(errcode);
3045         return JNI_EINVAL;
3046       }
3047       set_min_heap_size((uintx)long_initial_heap_size);
3048       // Currently the minimum size and the initial heap sizes are the same.
3049       // Can be overridden with -XX:InitialHeapSize.
3050       FLAG_SET_CMDLINE(uintx, InitialHeapSize, (uintx)long_initial_heap_size);
3051     // -Xmx
3052     } else if (match_option(option, "-Xmx", &tail) || match_option(option, "-XX:MaxHeapSize=", &tail)) {
3053       julong long_max_heap_size = 0;
3054       ArgsRange errcode = parse_memory_size(tail, &long_max_heap_size, 1);
3055       if (errcode != arg_in_range) {
3056         jio_fprintf(defaultStream::error_stream(),
3057                     "Invalid maximum heap size: %s\n", option->optionString);
3058         describe_range_error(errcode);
3059         return JNI_EINVAL;
3060       }
3061       FLAG_SET_CMDLINE(uintx, MaxHeapSize, (uintx)long_max_heap_size);
3062     // Xmaxf
3063     } else if (match_option(option, "-Xmaxf", &tail)) {
3064       char* err;
3065       int maxf = (int)(strtod(tail, &err) * 100);
3066       if (*err != '\0' || *tail == '\0' || maxf < 0 || maxf > 100) {
3067         jio_fprintf(defaultStream::error_stream(),
3068                     "Bad max heap free percentage size: %s\n",
3069                     option->optionString);
3070         return JNI_EINVAL;
3071       } else {
3072         FLAG_SET_CMDLINE(uintx, MaxHeapFreeRatio, maxf);
3073       }
3074     // Xminf
3075     } else if (match_option(option, "-Xminf", &tail)) {
3076       char* err;
3077       int minf = (int)(strtod(tail, &err) * 100);
3078       if (*err != '\0' || *tail == '\0' || minf < 0 || minf > 100) {
3079         jio_fprintf(defaultStream::error_stream(),
3080                     "Bad min heap free percentage size: %s\n",
3081                     option->optionString);
3082         return JNI_EINVAL;
3083       } else {
3084         FLAG_SET_CMDLINE(uintx, MinHeapFreeRatio, minf);
3085       }
3086     // -Xss
3087     } else if (match_option(option, "-Xss", &tail)) {
3088       julong long_ThreadStackSize = 0;
3089       ArgsRange errcode = parse_memory_size(tail, &long_ThreadStackSize, 1000);
3090       if (errcode != arg_in_range) {
3091         jio_fprintf(defaultStream::error_stream(),
3092                     "Invalid thread stack size: %s\n", option->optionString);
3093         describe_range_error(errcode);
3094         return JNI_EINVAL;
3095       }
3096       // Internally track ThreadStackSize in units of 1024 bytes.
3097       FLAG_SET_CMDLINE(intx, ThreadStackSize,
3098                               round_to((int)long_ThreadStackSize, K) / K);
3099     // -Xoss
3100     } else if (match_option(option, "-Xoss", &tail)) {
3101           // HotSpot does not have separate native and Java stacks, ignore silently for compatibility
3102     } else if (match_option(option, "-XX:CodeCacheExpansionSize=", &tail)) {
3103       julong long_CodeCacheExpansionSize = 0;
3104       ArgsRange errcode = parse_memory_size(tail, &long_CodeCacheExpansionSize, os::vm_page_size());
3105       if (errcode != arg_in_range) {
3106         jio_fprintf(defaultStream::error_stream(),
3107                    "Invalid argument: %s. Must be at least %luK.\n", option->optionString,
3108                    os::vm_page_size()/K);
3109         return JNI_EINVAL;
3110       }
3111       FLAG_SET_CMDLINE(uintx, CodeCacheExpansionSize, (uintx)long_CodeCacheExpansionSize);
3112     } else if (match_option(option, "-Xmaxjitcodesize", &tail) ||
3113                match_option(option, "-XX:ReservedCodeCacheSize=", &tail)) {
3114       julong long_ReservedCodeCacheSize = 0;
3115 
3116       ArgsRange errcode = parse_memory_size(tail, &long_ReservedCodeCacheSize, 1);
3117       if (errcode != arg_in_range) {
3118         jio_fprintf(defaultStream::error_stream(),
3119                     "Invalid maximum code cache size: %s.\n", option->optionString);
3120         return JNI_EINVAL;
3121       }
3122       FLAG_SET_CMDLINE(uintx, ReservedCodeCacheSize, (uintx)long_ReservedCodeCacheSize);
3123       //-XX:IncreaseFirstTierCompileThresholdAt=
3124       } else if (match_option(option, "-XX:IncreaseFirstTierCompileThresholdAt=", &tail)) {
3125         uintx uint_IncreaseFirstTierCompileThresholdAt = 0;
3126         if (!parse_uintx(tail, &uint_IncreaseFirstTierCompileThresholdAt, 0) || uint_IncreaseFirstTierCompileThresholdAt > 99) {
3127           jio_fprintf(defaultStream::error_stream(),
3128                       "Invalid value for IncreaseFirstTierCompileThresholdAt: %s. Should be between 0 and 99.\n",
3129                       option->optionString);
3130           return JNI_EINVAL;
3131         }
3132         FLAG_SET_CMDLINE(uintx, IncreaseFirstTierCompileThresholdAt, (uintx)uint_IncreaseFirstTierCompileThresholdAt);
3133     // -green
3134     } else if (match_option(option, "-green", &tail)) {
3135       jio_fprintf(defaultStream::error_stream(),
3136                   "Green threads support not available\n");
3137           return JNI_EINVAL;
3138     // -native
3139     } else if (match_option(option, "-native", &tail)) {
3140           // HotSpot always uses native threads, ignore silently for compatibility
3141     // -Xsqnopause
3142     } else if (match_option(option, "-Xsqnopause", &tail)) {
3143           // EVM option, ignore silently for compatibility
3144     // -Xrs
3145     } else if (match_option(option, "-Xrs", &tail)) {
3146           // Classic/EVM option, new functionality
3147       FLAG_SET_CMDLINE(bool, ReduceSignalUsage, true);
3148     } else if (match_option(option, "-Xusealtsigs", &tail)) {
3149           // change default internal VM signals used - lower case for back compat
3150       FLAG_SET_CMDLINE(bool, UseAltSigs, true);
3151     // -Xoptimize
3152     } else if (match_option(option, "-Xoptimize", &tail)) {
3153           // EVM option, ignore silently for compatibility
3154     // -Xprof
3155     } else if (match_option(option, "-Xprof", &tail)) {
3156 #if INCLUDE_FPROF
3157       _has_profile = true;
3158 #else // INCLUDE_FPROF
3159       jio_fprintf(defaultStream::error_stream(),
3160         "Flat profiling is not supported in this VM.\n");
3161       return JNI_ERR;
3162 #endif // INCLUDE_FPROF
3163     // -Xconcurrentio
3164     } else if (match_option(option, "-Xconcurrentio", &tail)) {
3165       FLAG_SET_CMDLINE(bool, UseLWPSynchronization, true);
3166       FLAG_SET_CMDLINE(bool, BackgroundCompilation, false);
3167       FLAG_SET_CMDLINE(intx, DeferThrSuspendLoopCount, 1);
3168       FLAG_SET_CMDLINE(bool, UseTLAB, false);
3169       FLAG_SET_CMDLINE(uintx, NewSizeThreadIncrease, 16 * K);  // 20Kb per thread added to new generation
3170 
3171       // -Xinternalversion
3172     } else if (match_option(option, "-Xinternalversion", &tail)) {
3173       jio_fprintf(defaultStream::output_stream(), "%s\n",
3174                   VM_Version::internal_vm_info_string());
3175       vm_exit(0);
3176 #ifndef PRODUCT
3177     // -Xprintflags
3178     } else if (match_option(option, "-Xprintflags", &tail)) {
3179       CommandLineFlags::printFlags(tty, false);
3180       vm_exit(0);
3181 #endif
3182     // -D
3183     } else if (match_option(option, "-D", &tail)) {
3184       if (CheckEndorsedAndExtDirs) {
3185         if (match_option(option, "-Djava.endorsed.dirs=", &tail)) {
3186           // abort if -Djava.endorsed.dirs is set
3187           jio_fprintf(defaultStream::output_stream(),
3188             "-Djava.endorsed.dirs will not be supported in a future release.\n"
3189             "Refer to JEP 220 for details (http://openjdk.java.net/jeps/220).\n");
3190           return JNI_EINVAL;
3191         }
3192         if (match_option(option, "-Djava.ext.dirs=", &tail)) {
3193           // abort if -Djava.ext.dirs is set
3194           jio_fprintf(defaultStream::output_stream(),
3195             "-Djava.ext.dirs will not be supported in a future release.\n"
3196             "Refer to JEP 220 for details (http://openjdk.java.net/jeps/220).\n");
3197           return JNI_EINVAL;
3198         }
3199       }
3200 
3201       if (!add_property(tail)) {
3202         return JNI_ENOMEM;
3203       }
3204       // Out of the box management support
3205       if (match_option(option, "-Dcom.sun.management", &tail)) {
3206 #if INCLUDE_MANAGEMENT
3207         FLAG_SET_CMDLINE(bool, ManagementServer, true);
3208 #else
3209         jio_fprintf(defaultStream::output_stream(),
3210           "-Dcom.sun.management is not supported in this VM.\n");
3211         return JNI_ERR;
3212 #endif
3213       }
3214     // -Xint
3215     } else if (match_option(option, "-Xint", &tail)) {
3216           set_mode_flags(_int);
3217     // -Xmixed
3218     } else if (match_option(option, "-Xmixed", &tail)) {
3219           set_mode_flags(_mixed);
3220     // -Xcomp
3221     } else if (match_option(option, "-Xcomp", &tail)) {
3222       // for testing the compiler; turn off all flags that inhibit compilation
3223           set_mode_flags(_comp);
3224     // -Xshare:dump
3225     } else if (match_option(option, "-Xshare:dump", &tail)) {
3226       FLAG_SET_CMDLINE(bool, DumpSharedSpaces, true);
3227       set_mode_flags(_int);     // Prevent compilation, which creates objects
3228     // -Xshare:on
3229     } else if (match_option(option, "-Xshare:on", &tail)) {
3230       FLAG_SET_CMDLINE(bool, UseSharedSpaces, true);
3231       FLAG_SET_CMDLINE(bool, RequireSharedSpaces, true);
3232     // -Xshare:auto
3233     } else if (match_option(option, "-Xshare:auto", &tail)) {
3234       FLAG_SET_CMDLINE(bool, UseSharedSpaces, true);
3235       FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false);
3236     // -Xshare:off
3237     } else if (match_option(option, "-Xshare:off", &tail)) {
3238       FLAG_SET_CMDLINE(bool, UseSharedSpaces, false);
3239       FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false);
3240     // -Xverify
3241     } else if (match_option(option, "-Xverify", &tail)) {
3242       if (strcmp(tail, ":all") == 0 || strcmp(tail, "") == 0) {
3243         FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, true);
3244         FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true);
3245       } else if (strcmp(tail, ":remote") == 0) {
3246         FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false);
3247         FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true);
3248       } else if (strcmp(tail, ":none") == 0) {
3249         FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false);
3250         FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, false);
3251       } else if (is_bad_option(option, args->ignoreUnrecognized, "verification")) {
3252         return JNI_EINVAL;
3253       }
3254     // -Xdebug
3255     } else if (match_option(option, "-Xdebug", &tail)) {
3256       // note this flag has been used, then ignore
3257       set_xdebug_mode(true);
3258     // -Xnoagent
3259     } else if (match_option(option, "-Xnoagent", &tail)) {
3260       // For compatibility with classic. HotSpot refuses to load the old style agent.dll.
3261     } else if (match_option(option, "-Xboundthreads", &tail)) {
3262       // Bind user level threads to kernel threads (Solaris only)
3263       FLAG_SET_CMDLINE(bool, UseBoundThreads, true);
3264     } else if (match_option(option, "-Xloggc:", &tail)) {
3265       // Redirect GC output to the file. -Xloggc:<filename>
3266       // ostream_init_log(), when called will use this filename
3267       // to initialize a fileStream.
3268       _gc_log_filename = strdup(tail);
3269      if (!is_filename_valid(_gc_log_filename)) {
3270        jio_fprintf(defaultStream::output_stream(),
3271                   "Invalid file name for use with -Xloggc: Filename can only contain the "
3272                   "characters [A-Z][a-z][0-9]-_.%%[p|t] but it has been %s\n"
3273                   "Note %%p or %%t can only be used once\n", _gc_log_filename);
3274         return JNI_EINVAL;
3275       }
3276       FLAG_SET_CMDLINE(bool, PrintGC, true);
3277       FLAG_SET_CMDLINE(bool, PrintGCTimeStamps, true);
3278 
3279     // JNI hooks
3280     } else if (match_option(option, "-Xcheck", &tail)) {
3281       if (!strcmp(tail, ":jni")) {
3282 #if !INCLUDE_JNI_CHECK
3283         warning("JNI CHECKING is not supported in this VM");
3284 #else
3285         CheckJNICalls = true;
3286 #endif // INCLUDE_JNI_CHECK
3287       } else if (is_bad_option(option, args->ignoreUnrecognized,
3288                                      "check")) {
3289         return JNI_EINVAL;
3290       }
3291     } else if (match_option(option, "vfprintf", &tail)) {
3292       _vfprintf_hook = CAST_TO_FN_PTR(vfprintf_hook_t, option->extraInfo);
3293     } else if (match_option(option, "exit", &tail)) {
3294       _exit_hook = CAST_TO_FN_PTR(exit_hook_t, option->extraInfo);
3295     } else if (match_option(option, "abort", &tail)) {
3296       _abort_hook = CAST_TO_FN_PTR(abort_hook_t, option->extraInfo);
3297     // -XX:+AggressiveHeap
3298     } else if (match_option(option, "-XX:+AggressiveHeap", &tail)) {
3299 
3300       // This option inspects the machine and attempts to set various
3301       // parameters to be optimal for long-running, memory allocation
3302       // intensive jobs.  It is intended for machines with large
3303       // amounts of cpu and memory.
3304 
3305       // initHeapSize is needed since _initial_heap_size is 4 bytes on a 32 bit
3306       // VM, but we may not be able to represent the total physical memory
3307       // available (like having 8gb of memory on a box but using a 32bit VM).
3308       // Thus, we need to make sure we're using a julong for intermediate
3309       // calculations.
3310       julong initHeapSize;
3311       julong total_memory = os::physical_memory();
3312 
3313       if (total_memory < (julong)256*M) {
3314         jio_fprintf(defaultStream::error_stream(),
3315                     "You need at least 256mb of memory to use -XX:+AggressiveHeap\n");
3316         vm_exit(1);
3317       }
3318 
3319       // The heap size is half of available memory, or (at most)
3320       // all of possible memory less 160mb (leaving room for the OS
3321       // when using ISM).  This is the maximum; because adaptive sizing
3322       // is turned on below, the actual space used may be smaller.
3323 
3324       initHeapSize = MIN2(total_memory / (julong)2,
3325                           total_memory - (julong)160*M);
3326 
3327       initHeapSize = limit_by_allocatable_memory(initHeapSize);
3328 
3329       if (FLAG_IS_DEFAULT(MaxHeapSize)) {
3330          FLAG_SET_CMDLINE(uintx, MaxHeapSize, initHeapSize);
3331          FLAG_SET_CMDLINE(uintx, InitialHeapSize, initHeapSize);
3332          // Currently the minimum size and the initial heap sizes are the same.
3333          set_min_heap_size(initHeapSize);
3334       }
3335       if (FLAG_IS_DEFAULT(NewSize)) {
3336          // Make the young generation 3/8ths of the total heap.
3337          FLAG_SET_CMDLINE(uintx, NewSize,
3338                                 ((julong)MaxHeapSize / (julong)8) * (julong)3);
3339          FLAG_SET_CMDLINE(uintx, MaxNewSize, NewSize);
3340       }
3341 
3342 #ifndef _ALLBSD_SOURCE  // UseLargePages is not yet supported on BSD.
3343       FLAG_SET_DEFAULT(UseLargePages, true);
3344 #endif
3345 
3346       // Increase some data structure sizes for efficiency
3347       FLAG_SET_CMDLINE(uintx, BaseFootPrintEstimate, MaxHeapSize);
3348       FLAG_SET_CMDLINE(bool, ResizeTLAB, false);
3349       FLAG_SET_CMDLINE(uintx, TLABSize, 256*K);
3350 
3351       // See the OldPLABSize comment below, but replace 'after promotion'
3352       // with 'after copying'.  YoungPLABSize is the size of the survivor
3353       // space per-gc-thread buffers.  The default is 4kw.
3354       FLAG_SET_CMDLINE(uintx, YoungPLABSize, 256*K);      // Note: this is in words
3355 
3356       // OldPLABSize is the size of the buffers in the old gen that
3357       // UseParallelGC uses to promote live data that doesn't fit in the
3358       // survivor spaces.  At any given time, there's one for each gc thread.
3359       // The default size is 1kw. These buffers are rarely used, since the
3360       // survivor spaces are usually big enough.  For specjbb, however, there
3361       // are occasions when there's lots of live data in the young gen
3362       // and we end up promoting some of it.  We don't have a definite
3363       // explanation for why bumping OldPLABSize helps, but the theory
3364       // is that a bigger PLAB results in retaining something like the
3365       // original allocation order after promotion, which improves mutator
3366       // locality.  A minor effect may be that larger PLABs reduce the
3367       // number of PLAB allocation events during gc.  The value of 8kw
3368       // was arrived at by experimenting with specjbb.
3369       FLAG_SET_CMDLINE(uintx, OldPLABSize, 8*K);  // Note: this is in words
3370 
3371       // Enable parallel GC and adaptive generation sizing
3372       FLAG_SET_CMDLINE(bool, UseParallelGC, true);
3373 
3374       // Encourage steady state memory management
3375       FLAG_SET_CMDLINE(uintx, ThresholdTolerance, 100);
3376 
3377       // This appears to improve mutator locality
3378       FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
3379 
3380       // Get around early Solaris scheduling bug
3381       // (affinity vs other jobs on system)
3382       // but disallow DR and offlining (5008695).
3383       FLAG_SET_CMDLINE(bool, BindGCTaskThreadsToCPUs, true);
3384 
3385     } else if (match_option(option, "-XX:+NeverTenure", &tail)) {
3386       // The last option must always win.
3387       FLAG_SET_CMDLINE(bool, AlwaysTenure, false);
3388       FLAG_SET_CMDLINE(bool, NeverTenure, true);
3389     } else if (match_option(option, "-XX:+AlwaysTenure", &tail)) {
3390       // The last option must always win.
3391       FLAG_SET_CMDLINE(bool, NeverTenure, false);
3392       FLAG_SET_CMDLINE(bool, AlwaysTenure, true);
3393     } else if (match_option(option, "-XX:+CMSPermGenSweepingEnabled", &tail) ||
3394                match_option(option, "-XX:-CMSPermGenSweepingEnabled", &tail)) {
3395       jio_fprintf(defaultStream::error_stream(),
3396         "Please use CMSClassUnloadingEnabled in place of "
3397         "CMSPermGenSweepingEnabled in the future\n");
3398     } else if (match_option(option, "-XX:+UseGCTimeLimit", &tail)) {
3399       FLAG_SET_CMDLINE(bool, UseGCOverheadLimit, true);
3400       jio_fprintf(defaultStream::error_stream(),
3401         "Please use -XX:+UseGCOverheadLimit in place of "
3402         "-XX:+UseGCTimeLimit in the future\n");
3403     } else if (match_option(option, "-XX:-UseGCTimeLimit", &tail)) {
3404       FLAG_SET_CMDLINE(bool, UseGCOverheadLimit, false);
3405       jio_fprintf(defaultStream::error_stream(),
3406         "Please use -XX:-UseGCOverheadLimit in place of "
3407         "-XX:-UseGCTimeLimit in the future\n");
3408     // The TLE options are for compatibility with 1.3 and will be
3409     // removed without notice in a future release.  These options
3410     // are not to be documented.
3411     } else if (match_option(option, "-XX:MaxTLERatio=", &tail)) {
3412       // No longer used.
3413     } else if (match_option(option, "-XX:+ResizeTLE", &tail)) {
3414       FLAG_SET_CMDLINE(bool, ResizeTLAB, true);
3415     } else if (match_option(option, "-XX:-ResizeTLE", &tail)) {
3416       FLAG_SET_CMDLINE(bool, ResizeTLAB, false);
3417     } else if (match_option(option, "-XX:+PrintTLE", &tail)) {
3418       FLAG_SET_CMDLINE(bool, PrintTLAB, true);
3419     } else if (match_option(option, "-XX:-PrintTLE", &tail)) {
3420       FLAG_SET_CMDLINE(bool, PrintTLAB, false);
3421     } else if (match_option(option, "-XX:TLEFragmentationRatio=", &tail)) {
3422       // No longer used.
3423     } else if (match_option(option, "-XX:TLESize=", &tail)) {
3424       julong long_tlab_size = 0;
3425       ArgsRange errcode = parse_memory_size(tail, &long_tlab_size, 1);
3426       if (errcode != arg_in_range) {
3427         jio_fprintf(defaultStream::error_stream(),
3428                     "Invalid TLAB size: %s\n", option->optionString);
3429         describe_range_error(errcode);
3430         return JNI_EINVAL;
3431       }
3432       FLAG_SET_CMDLINE(uintx, TLABSize, long_tlab_size);
3433     } else if (match_option(option, "-XX:TLEThreadRatio=", &tail)) {
3434       // No longer used.
3435     } else if (match_option(option, "-XX:+UseTLE", &tail)) {
3436       FLAG_SET_CMDLINE(bool, UseTLAB, true);
3437     } else if (match_option(option, "-XX:-UseTLE", &tail)) {
3438       FLAG_SET_CMDLINE(bool, UseTLAB, false);
3439     } else if (match_option(option, "-XX:+DisplayVMOutputToStderr", &tail)) {
3440       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, false);
3441       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, true);
3442     } else if (match_option(option, "-XX:+DisplayVMOutputToStdout", &tail)) {
3443       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, false);
3444       FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, true);
3445     } else if (match_option(option, "-XX:+ExtendedDTraceProbes", &tail)) {
3446 #if defined(DTRACE_ENABLED)
3447       FLAG_SET_CMDLINE(bool, ExtendedDTraceProbes, true);
3448       FLAG_SET_CMDLINE(bool, DTraceMethodProbes, true);
3449       FLAG_SET_CMDLINE(bool, DTraceAllocProbes, true);
3450       FLAG_SET_CMDLINE(bool, DTraceMonitorProbes, true);
3451 #else // defined(DTRACE_ENABLED)
3452       jio_fprintf(defaultStream::error_stream(),
3453                   "ExtendedDTraceProbes flag is not applicable for this configuration\n");
3454       return JNI_EINVAL;
3455 #endif // defined(DTRACE_ENABLED)
3456 #ifdef ASSERT
3457     } else if (match_option(option, "-XX:+FullGCALot", &tail)) {
3458       FLAG_SET_CMDLINE(bool, FullGCALot, true);
3459       // disable scavenge before parallel mark-compact
3460       FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
3461 #endif
3462     } else if (match_option(option, "-XX:CMSParPromoteBlocksToClaim=", &tail)) {
3463       julong cms_blocks_to_claim = (julong)atol(tail);
3464       FLAG_SET_CMDLINE(uintx, CMSParPromoteBlocksToClaim, cms_blocks_to_claim);
3465       jio_fprintf(defaultStream::error_stream(),
3466         "Please use -XX:OldPLABSize in place of "
3467         "-XX:CMSParPromoteBlocksToClaim in the future\n");
3468     } else if (match_option(option, "-XX:ParCMSPromoteBlocksToClaim=", &tail)) {
3469       julong cms_blocks_to_claim = (julong)atol(tail);
3470       FLAG_SET_CMDLINE(uintx, CMSParPromoteBlocksToClaim, cms_blocks_to_claim);
3471       jio_fprintf(defaultStream::error_stream(),
3472         "Please use -XX:OldPLABSize in place of "
3473         "-XX:ParCMSPromoteBlocksToClaim in the future\n");
3474     } else if (match_option(option, "-XX:ParallelGCOldGenAllocBufferSize=", &tail)) {
3475       julong old_plab_size = 0;
3476       ArgsRange errcode = parse_memory_size(tail, &old_plab_size, 1);
3477       if (errcode != arg_in_range) {
3478         jio_fprintf(defaultStream::error_stream(),
3479                     "Invalid old PLAB size: %s\n", option->optionString);
3480         describe_range_error(errcode);
3481         return JNI_EINVAL;
3482       }
3483       FLAG_SET_CMDLINE(uintx, OldPLABSize, old_plab_size);
3484       jio_fprintf(defaultStream::error_stream(),
3485                   "Please use -XX:OldPLABSize in place of "
3486                   "-XX:ParallelGCOldGenAllocBufferSize in the future\n");
3487     } else if (match_option(option, "-XX:ParallelGCToSpaceAllocBufferSize=", &tail)) {
3488       julong young_plab_size = 0;
3489       ArgsRange errcode = parse_memory_size(tail, &young_plab_size, 1);
3490       if (errcode != arg_in_range) {
3491         jio_fprintf(defaultStream::error_stream(),
3492                     "Invalid young PLAB size: %s\n", option->optionString);
3493         describe_range_error(errcode);
3494         return JNI_EINVAL;
3495       }
3496       FLAG_SET_CMDLINE(uintx, YoungPLABSize, young_plab_size);
3497       jio_fprintf(defaultStream::error_stream(),
3498                   "Please use -XX:YoungPLABSize in place of "
3499                   "-XX:ParallelGCToSpaceAllocBufferSize in the future\n");
3500     } else if (match_option(option, "-XX:CMSMarkStackSize=", &tail) ||
3501                match_option(option, "-XX:G1MarkStackSize=", &tail)) {
3502       julong stack_size = 0;
3503       ArgsRange errcode = parse_memory_size(tail, &stack_size, 1);
3504       if (errcode != arg_in_range) {
3505         jio_fprintf(defaultStream::error_stream(),
3506                     "Invalid mark stack size: %s\n", option->optionString);
3507         describe_range_error(errcode);
3508         return JNI_EINVAL;
3509       }
3510       FLAG_SET_CMDLINE(uintx, MarkStackSize, stack_size);
3511     } else if (match_option(option, "-XX:CMSMarkStackSizeMax=", &tail)) {
3512       julong max_stack_size = 0;
3513       ArgsRange errcode = parse_memory_size(tail, &max_stack_size, 1);
3514       if (errcode != arg_in_range) {
3515         jio_fprintf(defaultStream::error_stream(),
3516                     "Invalid maximum mark stack size: %s\n",
3517                     option->optionString);
3518         describe_range_error(errcode);
3519         return JNI_EINVAL;
3520       }
3521       FLAG_SET_CMDLINE(uintx, MarkStackSizeMax, max_stack_size);
3522     } else if (match_option(option, "-XX:ParallelMarkingThreads=", &tail) ||
3523                match_option(option, "-XX:ParallelCMSThreads=", &tail)) {
3524       uintx conc_threads = 0;
3525       if (!parse_uintx(tail, &conc_threads, 1)) {
3526         jio_fprintf(defaultStream::error_stream(),
3527                     "Invalid concurrent threads: %s\n", option->optionString);
3528         return JNI_EINVAL;
3529       }
3530       FLAG_SET_CMDLINE(uintx, ConcGCThreads, conc_threads);
3531     } else if (match_option(option, "-XX:MaxDirectMemorySize=", &tail)) {
3532       julong max_direct_memory_size = 0;
3533       ArgsRange errcode = parse_memory_size(tail, &max_direct_memory_size, 0);
3534       if (errcode != arg_in_range) {
3535         jio_fprintf(defaultStream::error_stream(),
3536                     "Invalid maximum direct memory size: %s\n",
3537                     option->optionString);
3538         describe_range_error(errcode);
3539         return JNI_EINVAL;
3540       }
3541       FLAG_SET_CMDLINE(uintx, MaxDirectMemorySize, max_direct_memory_size);
3542     } else if (match_option(option, "-XX:+UseVMInterruptibleIO", &tail)) {
3543       // NOTE! In JDK 9, the UseVMInterruptibleIO flag will completely go
3544       //       away and will cause VM initialization failures!
3545       warning("-XX:+UseVMInterruptibleIO is obsolete and will be removed in a future release.");
3546       FLAG_SET_CMDLINE(bool, UseVMInterruptibleIO, true);
3547 #if !INCLUDE_MANAGEMENT
3548     } else if (match_option(option, "-XX:+ManagementServer", &tail)) {
3549         jio_fprintf(defaultStream::error_stream(),
3550           "ManagementServer is not supported in this VM.\n");
3551         return JNI_ERR;
3552 #endif // INCLUDE_MANAGEMENT
3553     } else if (match_option(option, "-XX:", &tail)) { // -XX:xxxx
3554       // Skip -XX:Flags= since that case has already been handled
3555       if (strncmp(tail, "Flags=", strlen("Flags=")) != 0) {
3556         if (!process_argument(tail, args->ignoreUnrecognized, origin)) {
3557           return JNI_EINVAL;
3558         }
3559       }
3560     // Unknown option
3561     } else if (is_bad_option(option, args->ignoreUnrecognized)) {
3562       return JNI_ERR;
3563     }
3564   }
3565 
3566   // PrintSharedArchiveAndExit will turn on
3567   //   -Xshare:on
3568   //   -XX:+TraceClassPaths
3569   if (PrintSharedArchiveAndExit) {
3570     FLAG_SET_CMDLINE(bool, UseSharedSpaces, true);
3571     FLAG_SET_CMDLINE(bool, RequireSharedSpaces, true);
3572     FLAG_SET_CMDLINE(bool, TraceClassPaths, true);
3573   }
3574 
3575   // Change the default value for flags  which have different default values
3576   // when working with older JDKs.
3577 #ifdef LINUX
3578  if (JDK_Version::current().compare_major(6) <= 0 &&
3579       FLAG_IS_DEFAULT(UseLinuxPosixThreadCPUClocks)) {
3580     FLAG_SET_DEFAULT(UseLinuxPosixThreadCPUClocks, false);
3581   }
3582 #endif // LINUX
3583   fix_appclasspath();
3584   return JNI_OK;
3585 }
3586 
3587 // Remove all empty paths from the app classpath (if IgnoreEmptyClassPaths is enabled)
3588 //
3589 // This is necessary because some apps like to specify classpath like -cp foo.jar:${XYZ}:bar.jar
3590 // in their start-up scripts. If XYZ is empty, the classpath will look like "-cp foo.jar::bar.jar".
3591 // Java treats such empty paths as if the user specified "-cp foo.jar:.:bar.jar". I.e., an empty
3592 // path is treated as the current directory.
3593 //
3594 // This causes problems with CDS, which requires that all directories specified in the classpath
3595 // must be empty. In most cases, applications do NOT want to load classes from the current
3596 // directory anyway. Adding -XX:+IgnoreEmptyClassPaths will make these applications' start-up
3597 // scripts compatible with CDS.
3598 void Arguments::fix_appclasspath() {
3599   if (IgnoreEmptyClassPaths) {
3600     const char separator = *os::path_separator();
3601     const char* src = _java_class_path->value();
3602 
3603     // skip over all the leading empty paths
3604     while (*src == separator) {
3605       src ++;
3606     }
3607 
3608     char* copy = AllocateHeap(strlen(src) + 1, mtInternal);
3609     strncpy(copy, src, strlen(src) + 1);
3610 
3611     // trim all trailing empty paths
3612     for (char* tail = copy + strlen(copy) - 1; tail >= copy && *tail == separator; tail--) {
3613       *tail = '\0';
3614     }
3615 
3616     char from[3] = {separator, separator, '\0'};
3617     char to  [2] = {separator, '\0'};
3618     while (StringUtils::replace_no_expand(copy, from, to) > 0) {
3619       // Keep replacing "::" -> ":" until we have no more "::" (non-windows)
3620       // Keep replacing ";;" -> ";" until we have no more ";;" (windows)
3621     }
3622 
3623     _java_class_path->set_value(copy);
3624     FreeHeap(copy); // a copy was made by set_value, so don't need this anymore
3625   }
3626 
3627   if (!PrintSharedArchiveAndExit) {
3628     ClassLoader::trace_class_path(tty, "[classpath: ", _java_class_path->value());
3629   }
3630 }
3631 
3632 static bool has_jar_files(const char* directory) {
3633   DIR* dir = os::opendir(directory);
3634   if (dir == NULL) return false;
3635 
3636   struct dirent *entry;
3637   char *dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory), mtInternal);
3638   bool hasJarFile = false;
3639   while (!hasJarFile && (entry = os::readdir(dir, (dirent *) dbuf)) != NULL) {
3640     const char* name = entry->d_name;
3641     const char* ext = name + strlen(name) - 4;
3642     hasJarFile = ext > name && (os::file_name_strcmp(ext, ".jar") == 0);
3643   }
3644   FREE_C_HEAP_ARRAY(char, dbuf, mtInternal);
3645   os::closedir(dir);
3646   return hasJarFile ;
3647 }
3648 
3649 // returns the number of directories in the given path containing JAR files
3650 // If the skip argument is not NULL, it will skip that directory
3651 static int check_non_empty_dirs(const char* path, const char* type, const char* skip) {
3652   const char separator = *os::path_separator();
3653   const char* const end = path + strlen(path);
3654   int nonEmptyDirs = 0;
3655   while (path < end) {
3656     const char* tmp_end = strchr(path, separator);
3657     if (tmp_end == NULL) {
3658       if ((skip == NULL || strcmp(path, skip) != 0) && has_jar_files(path)) {
3659         nonEmptyDirs++;
3660         jio_fprintf(defaultStream::output_stream(),
3661           "Non-empty %s directory: %s\n", type, path);
3662       }
3663       path = end;
3664     } else {
3665       char* dirpath = NEW_C_HEAP_ARRAY(char, tmp_end - path + 1, mtInternal);
3666       memcpy(dirpath, path, tmp_end - path);
3667       dirpath[tmp_end - path] = '\0';
3668       if ((skip == NULL || strcmp(dirpath, skip) != 0) && has_jar_files(dirpath)) {
3669         nonEmptyDirs++;
3670         jio_fprintf(defaultStream::output_stream(),
3671           "Non-empty %s directory: %s\n", type, dirpath);
3672       }
3673       FREE_C_HEAP_ARRAY(char, dirpath, mtInternal);
3674       path = tmp_end + 1;
3675     }
3676   }
3677   return nonEmptyDirs;
3678 }
3679 
3680 // Returns true if endorsed standards override mechanism and extension mechanism
3681 // are not used.
3682 static bool check_endorsed_and_ext_dirs() {
3683   if (!CheckEndorsedAndExtDirs)
3684     return true;
3685 
3686   char endorsedDir[JVM_MAXPATHLEN];
3687   char extDir[JVM_MAXPATHLEN];
3688   const char* fileSep = os::file_separator();
3689   jio_snprintf(endorsedDir, sizeof(endorsedDir), "%s%slib%sendorsed",
3690                Arguments::get_java_home(), fileSep, fileSep);
3691   jio_snprintf(extDir, sizeof(extDir), "%s%slib%sext",
3692                Arguments::get_java_home(), fileSep, fileSep);
3693 
3694   // check endorsed directory
3695   int nonEmptyDirs = check_non_empty_dirs(Arguments::get_endorsed_dir(), "endorsed", NULL);
3696 
3697   // check the extension directories but skip the default lib/ext directory
3698   nonEmptyDirs += check_non_empty_dirs(Arguments::get_ext_dirs(), "extension", extDir);
3699 
3700   // List of JAR files installed in the default lib/ext directory.
3701   // -XX:+CheckEndorsedAndExtDirs checks if any non-JDK file installed
3702   static const char* jdk_ext_jars[] = {
3703       "access-bridge-32.jar",
3704       "access-bridge-64.jar",
3705       "access-bridge.jar",
3706       "cldrdata.jar",
3707       "dnsns.jar",
3708       "jaccess.jar",
3709       "jfxrt.jar",
3710       "localedata.jar",
3711       "nashorn.jar",
3712       "sunec.jar",
3713       "sunjce_provider.jar",
3714       "sunmscapi.jar",
3715       "sunpkcs11.jar",
3716       "ucrypto.jar",
3717       "zipfs.jar",
3718       NULL
3719   };
3720 
3721   // check if the default lib/ext directory has any non-JDK jar files; if so, error
3722   DIR* dir = os::opendir(extDir);
3723   if (dir != NULL) {
3724     int num_ext_jars = 0;
3725     struct dirent *entry;
3726     char *dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(extDir), mtInternal);
3727     while ((entry = os::readdir(dir, (dirent *) dbuf)) != NULL) {
3728       const char* name = entry->d_name;
3729       const char* ext = name + strlen(name) - 4;
3730       if (ext > name && (os::file_name_strcmp(ext, ".jar") == 0)) {
3731         bool is_jdk_jar = false;
3732         const char* jarfile = NULL;
3733         for (int i=0; (jarfile = jdk_ext_jars[i]) != NULL; i++) {
3734           if (os::file_name_strcmp(name, jarfile) == 0) {
3735             is_jdk_jar = true;
3736             break;
3737           }
3738         }
3739         if (!is_jdk_jar) {
3740           jio_fprintf(defaultStream::output_stream(),
3741             "%s installed in <JAVA_HOME>/lib/ext\n", name);
3742           num_ext_jars++;
3743         }
3744       }
3745     }
3746     FREE_C_HEAP_ARRAY(char, dbuf, mtInternal);
3747     os::closedir(dir);
3748     if (num_ext_jars > 0) {
3749       nonEmptyDirs += 1;
3750     }
3751   }
3752 
3753   // check if the default lib/endorsed directory exists; if so, error
3754   dir = os::opendir(endorsedDir);
3755   if (dir != NULL) {
3756     jio_fprintf(defaultStream::output_stream(), "<JAVA_HOME>/lib/endorsed exists\n");
3757     os::closedir(dir);
3758     nonEmptyDirs += 1;
3759   }
3760 
3761   if (nonEmptyDirs > 0) {
3762     jio_fprintf(defaultStream::output_stream(),
3763       "Endorsed standards override mechanism and extension mechanism "
3764       "will not be supported in a future release.\n"
3765       "Refer to JEP 220 for details (http://openjdk.java.net/jeps/220).\n");
3766     return false;
3767   }
3768 
3769   return true;
3770 }
3771 
3772 jint Arguments::finalize_vm_init_args(SysClassPath* scp_p, bool scp_assembly_required) {
3773   // This must be done after all -D arguments have been processed.
3774   scp_p->expand_endorsed();
3775 
3776   if (scp_assembly_required || scp_p->get_endorsed() != NULL) {
3777     // Assemble the bootclasspath elements into the final path.
3778     Arguments::set_sysclasspath(scp_p->combined_path());
3779   }
3780 
3781   if (!check_endorsed_and_ext_dirs()) {
3782     return JNI_ERR;
3783   }
3784 
3785   // This must be done after all arguments have been processed.
3786   // java_compiler() true means set to "NONE" or empty.
3787   if (java_compiler() && !xdebug_mode()) {
3788     // For backwards compatibility, we switch to interpreted mode if
3789     // -Djava.compiler="NONE" or "" is specified AND "-Xdebug" was
3790     // not specified.
3791     set_mode_flags(_int);
3792   }
3793   if (CompileThreshold == 0) {
3794     set_mode_flags(_int);
3795   }
3796 
3797   // eventually fix up InitialTenuringThreshold if only MaxTenuringThreshold is set
3798   if (FLAG_IS_DEFAULT(InitialTenuringThreshold) && (InitialTenuringThreshold > MaxTenuringThreshold)) {
3799     FLAG_SET_ERGO(uintx, InitialTenuringThreshold, MaxTenuringThreshold);
3800   }
3801 
3802 #ifndef COMPILER2
3803   // Don't degrade server performance for footprint
3804   if (FLAG_IS_DEFAULT(UseLargePages) &&
3805       MaxHeapSize < LargePageHeapSizeThreshold) {
3806     // No need for large granularity pages w/small heaps.
3807     // Note that large pages are enabled/disabled for both the
3808     // Java heap and the code cache.
3809     FLAG_SET_DEFAULT(UseLargePages, false);
3810   }
3811 
3812 #else
3813   if (!FLAG_IS_DEFAULT(OptoLoopAlignment) && FLAG_IS_DEFAULT(MaxLoopPad)) {
3814     FLAG_SET_DEFAULT(MaxLoopPad, OptoLoopAlignment-1);
3815   }
3816 #endif
3817 
3818 #ifndef TIERED
3819   // Tiered compilation is undefined.
3820   UNSUPPORTED_OPTION(TieredCompilation, "TieredCompilation");
3821 #endif
3822 
3823   // If we are running in a headless jre, force java.awt.headless property
3824   // to be true unless the property has already been set.
3825   // Also allow the OS environment variable JAVA_AWT_HEADLESS to set headless state.
3826   if (os::is_headless_jre()) {
3827     const char* headless = Arguments::get_property("java.awt.headless");
3828     if (headless == NULL) {
3829       char envbuffer[128];
3830       if (!os::getenv("JAVA_AWT_HEADLESS", envbuffer, sizeof(envbuffer))) {
3831         if (!add_property("java.awt.headless=true")) {
3832           return JNI_ENOMEM;
3833         }
3834       } else {
3835         char buffer[256];
3836         jio_snprintf(buffer, 256, "java.awt.headless=%s", envbuffer);
3837         if (!add_property(buffer)) {
3838           return JNI_ENOMEM;
3839         }
3840       }
3841     }
3842   }
3843 
3844   if (!check_vm_args_consistency()) {
3845     return JNI_ERR;
3846   }
3847 
3848   return JNI_OK;
3849 }
3850 
3851 jint Arguments::parse_java_options_environment_variable(SysClassPath* scp_p, bool* scp_assembly_required_p) {
3852   return parse_options_environment_variable("_JAVA_OPTIONS", scp_p,
3853                                             scp_assembly_required_p);
3854 }
3855 
3856 jint Arguments::parse_java_tool_options_environment_variable(SysClassPath* scp_p, bool* scp_assembly_required_p) {
3857   return parse_options_environment_variable("JAVA_TOOL_OPTIONS", scp_p,
3858                                             scp_assembly_required_p);
3859 }
3860 
3861 jint Arguments::parse_options_environment_variable(const char* name, SysClassPath* scp_p, bool* scp_assembly_required_p) {
3862   const int N_MAX_OPTIONS = 64;
3863   const int OPTION_BUFFER_SIZE = 1024;
3864   char buffer[OPTION_BUFFER_SIZE];
3865 
3866   // The variable will be ignored if it exceeds the length of the buffer.
3867   // Don't check this variable if user has special privileges
3868   // (e.g. unix su command).
3869   if (os::getenv(name, buffer, sizeof(buffer)) &&
3870       !os::have_special_privileges()) {
3871     JavaVMOption options[N_MAX_OPTIONS];      // Construct option array
3872     jio_fprintf(defaultStream::error_stream(),
3873                 "Picked up %s: %s\n", name, buffer);
3874     char* rd = buffer;                        // pointer to the input string (rd)
3875     int i;
3876     for (i = 0; i < N_MAX_OPTIONS;) {         // repeat for all options in the input string
3877       while (isspace(*rd)) rd++;              // skip whitespace
3878       if (*rd == 0) break;                    // we re done when the input string is read completely
3879 
3880       // The output, option string, overwrites the input string.
3881       // Because of quoting, the pointer to the option string (wrt) may lag the pointer to
3882       // input string (rd).
3883       char* wrt = rd;
3884 
3885       options[i++].optionString = wrt;        // Fill in option
3886       while (*rd != 0 && !isspace(*rd)) {     // unquoted strings terminate with a space or NULL
3887         if (*rd == '\'' || *rd == '"') {      // handle a quoted string
3888           int quote = *rd;                    // matching quote to look for
3889           rd++;                               // don't copy open quote
3890           while (*rd != quote) {              // include everything (even spaces) up until quote
3891             if (*rd == 0) {                   // string termination means unmatched string
3892               jio_fprintf(defaultStream::error_stream(),
3893                           "Unmatched quote in %s\n", name);
3894               return JNI_ERR;
3895             }
3896             *wrt++ = *rd++;                   // copy to option string
3897           }
3898           rd++;                               // don't copy close quote
3899         } else {
3900           *wrt++ = *rd++;                     // copy to option string
3901         }
3902       }
3903       // Need to check if we're done before writing a NULL,
3904       // because the write could be to the byte that rd is pointing to.
3905       if (*rd++ == 0) {
3906         *wrt = 0;
3907         break;
3908       }
3909       *wrt = 0;                               // Zero terminate option
3910     }
3911     // Construct JavaVMInitArgs structure and parse as if it was part of the command line
3912     JavaVMInitArgs vm_args;
3913     vm_args.version = JNI_VERSION_1_2;
3914     vm_args.options = options;
3915     vm_args.nOptions = i;
3916     vm_args.ignoreUnrecognized = IgnoreUnrecognizedVMOptions;
3917 
3918     if (PrintVMOptions) {
3919       const char* tail;
3920       for (int i = 0; i < vm_args.nOptions; i++) {
3921         const JavaVMOption *option = vm_args.options + i;
3922         if (match_option(option, "-XX:", &tail)) {
3923           logOption(tail);
3924         }
3925       }
3926     }
3927 
3928     return(parse_each_vm_init_arg(&vm_args, scp_p, scp_assembly_required_p, Flag::ENVIRON_VAR));
3929   }
3930   return JNI_OK;
3931 }
3932 
3933 void Arguments::set_shared_spaces_flags() {
3934   if (DumpSharedSpaces) {
3935     if (FailOverToOldVerifier) {
3936       // Don't fall back to the old verifier on verification failure. If a
3937       // class fails verification with the split verifier, it might fail the
3938       // CDS runtime verifier constraint check. In that case, we don't want
3939       // to share the class. We only archive classes that pass the split verifier.
3940       FLAG_SET_DEFAULT(FailOverToOldVerifier, false);
3941     }
3942 
3943     if (RequireSharedSpaces) {
3944       warning("cannot dump shared archive while using shared archive");
3945     }
3946     UseSharedSpaces = false;
3947 #ifdef _LP64
3948     if (!UseCompressedOops || !UseCompressedClassPointers) {
3949       vm_exit_during_initialization(
3950         "Cannot dump shared archive when UseCompressedOops or UseCompressedClassPointers is off.", NULL);
3951     }
3952   } else {
3953     if (!UseCompressedOops || !UseCompressedClassPointers) {
3954       no_shared_spaces("UseCompressedOops and UseCompressedClassPointers must be on for UseSharedSpaces.");
3955     }
3956 #endif
3957   }
3958 }
3959 
3960 #if !INCLUDE_ALL_GCS
3961 static void force_serial_gc() {
3962   FLAG_SET_DEFAULT(UseSerialGC, true);
3963   FLAG_SET_DEFAULT(CMSIncrementalMode, false);  // special CMS suboption
3964   UNSUPPORTED_GC_OPTION(UseG1GC);
3965   UNSUPPORTED_GC_OPTION(UseParallelGC);
3966   UNSUPPORTED_GC_OPTION(UseParallelOldGC);
3967   UNSUPPORTED_GC_OPTION(UseConcMarkSweepGC);
3968   UNSUPPORTED_GC_OPTION(UseParNewGC);
3969 }
3970 #endif // INCLUDE_ALL_GCS
3971 
3972 // Sharing support
3973 // Construct the path to the archive
3974 static char* get_shared_archive_path() {
3975   char *shared_archive_path;
3976   if (SharedArchiveFile == NULL) {
3977     char jvm_path[JVM_MAXPATHLEN];
3978     os::jvm_path(jvm_path, sizeof(jvm_path));
3979     char *end = strrchr(jvm_path, *os::file_separator());
3980     if (end != NULL) *end = '\0';
3981     size_t jvm_path_len = strlen(jvm_path);
3982     size_t file_sep_len = strlen(os::file_separator());
3983     shared_archive_path = NEW_C_HEAP_ARRAY(char, jvm_path_len +
3984         file_sep_len + 20, mtInternal);
3985     if (shared_archive_path != NULL) {
3986       strncpy(shared_archive_path, jvm_path, jvm_path_len + 1);
3987       strncat(shared_archive_path, os::file_separator(), file_sep_len);
3988       strncat(shared_archive_path, "classes.jsa", 11);
3989     }
3990   } else {
3991     shared_archive_path = NEW_C_HEAP_ARRAY(char, strlen(SharedArchiveFile) + 1, mtInternal);
3992     if (shared_archive_path != NULL) {
3993       strncpy(shared_archive_path, SharedArchiveFile, strlen(SharedArchiveFile) + 1);
3994     }
3995   }
3996   return shared_archive_path;
3997 }
3998 
3999 #ifndef PRODUCT
4000 // Determine whether LogVMOutput should be implicitly turned on.
4001 static bool use_vm_log() {
4002   if (LogCompilation || !FLAG_IS_DEFAULT(LogFile) ||
4003       PrintCompilation || PrintInlining || PrintDependencies || PrintNativeNMethods ||
4004       PrintDebugInfo || PrintRelocations || PrintNMethods || PrintExceptionHandlers ||
4005       PrintAssembly || TraceDeoptimization || TraceDependencies ||
4006       (VerifyDependencies && FLAG_IS_CMDLINE(VerifyDependencies))) {
4007     return true;
4008   }
4009 
4010 #ifdef COMPILER1
4011   if (PrintC1Statistics) {
4012     return true;
4013   }
4014 #endif // COMPILER1
4015 
4016 #ifdef COMPILER2
4017   if (PrintOptoAssembly || PrintOptoStatistics) {
4018     return true;
4019   }
4020 #endif // COMPILER2
4021 
4022   return false;
4023 }
4024 #endif // PRODUCT
4025 
4026 // Parse entry point called from JNI_CreateJavaVM
4027 
4028 jint Arguments::parse(const JavaVMInitArgs* args) {
4029 
4030   // Remaining part of option string
4031   const char* tail;
4032 
4033   // If flag "-XX:Flags=flags-file" is used it will be the first option to be processed.
4034   const char* hotspotrc = ".hotspotrc";
4035   bool settings_file_specified = false;
4036   bool needs_hotspotrc_warning = false;
4037 
4038   ArgumentsExt::process_options(args);
4039 
4040   const char* flags_file;
4041   int index;
4042   for (index = 0; index < args->nOptions; index++) {
4043     const JavaVMOption *option = args->options + index;
4044     if (match_option(option, "-XX:Flags=", &tail)) {
4045       flags_file = tail;
4046       settings_file_specified = true;
4047     }
4048     if (match_option(option, "-XX:+PrintVMOptions", &tail)) {
4049       PrintVMOptions = true;
4050     }
4051     if (match_option(option, "-XX:-PrintVMOptions", &tail)) {
4052       PrintVMOptions = false;
4053     }
4054     if (match_option(option, "-XX:+IgnoreUnrecognizedVMOptions", &tail)) {
4055       IgnoreUnrecognizedVMOptions = true;
4056     }
4057     if (match_option(option, "-XX:-IgnoreUnrecognizedVMOptions", &tail)) {
4058       IgnoreUnrecognizedVMOptions = false;
4059     }
4060     if (match_option(option, "-XX:+PrintFlagsInitial", &tail)) {
4061       CommandLineFlags::printFlags(tty, false);
4062       vm_exit(0);
4063     }
4064     if (match_option(option, "-XX:NativeMemoryTracking", &tail)) {
4065 #if INCLUDE_NMT
4066       // The launcher did not setup nmt environment variable properly.
4067       if (!MemTracker::check_launcher_nmt_support(tail)) {
4068         warning("Native Memory Tracking did not setup properly, using wrong launcher?");
4069       }
4070 
4071       // Verify if nmt option is valid.
4072       if (MemTracker::verify_nmt_option()) {
4073         // Late initialization, still in single-threaded mode.
4074         if (MemTracker::tracking_level() >= NMT_summary) {
4075           MemTracker::init();
4076         }
4077       } else {
4078         vm_exit_during_initialization("Syntax error, expecting -XX:NativeMemoryTracking=[off|summary|detail]", NULL);
4079       }
4080 #else
4081       jio_fprintf(defaultStream::error_stream(),
4082         "Native Memory Tracking is not supported in this VM\n");
4083       return JNI_ERR;
4084 #endif
4085     }
4086 
4087 
4088 #ifndef PRODUCT
4089     if (match_option(option, "-XX:+PrintFlagsWithComments", &tail)) {
4090       CommandLineFlags::printFlags(tty, true);
4091       vm_exit(0);
4092     }
4093 #endif
4094   }
4095 
4096   if (IgnoreUnrecognizedVMOptions) {
4097     // uncast const to modify the flag args->ignoreUnrecognized
4098     *(jboolean*)(&args->ignoreUnrecognized) = true;
4099   }
4100 
4101   // Parse specified settings file
4102   if (settings_file_specified) {
4103     if (!process_settings_file(flags_file, true, args->ignoreUnrecognized)) {
4104       return JNI_EINVAL;
4105     }
4106   } else {
4107 #ifdef ASSERT
4108     // Parse default .hotspotrc settings file
4109     if (!process_settings_file(".hotspotrc", false, args->ignoreUnrecognized)) {
4110       return JNI_EINVAL;
4111     }
4112 #else
4113     struct stat buf;
4114     if (os::stat(hotspotrc, &buf) == 0) {
4115       needs_hotspotrc_warning = true;
4116     }
4117 #endif
4118   }
4119 
4120   if (PrintVMOptions) {
4121     for (index = 0; index < args->nOptions; index++) {
4122       const JavaVMOption *option = args->options + index;
4123       if (match_option(option, "-XX:", &tail)) {
4124         logOption(tail);
4125       }
4126     }
4127   }
4128 
4129   // Parse JavaVMInitArgs structure passed in, as well as JAVA_TOOL_OPTIONS and _JAVA_OPTIONS
4130   jint result = parse_vm_init_args(args);
4131   if (result != JNI_OK) {
4132     return result;
4133   }
4134 
4135   // Call get_shared_archive_path() here, after possible SharedArchiveFile option got parsed.
4136   SharedArchivePath = get_shared_archive_path();
4137   if (SharedArchivePath == NULL) {
4138     return JNI_ENOMEM;
4139   }
4140 
4141   // Set up VerifySharedSpaces
4142   if (FLAG_IS_DEFAULT(VerifySharedSpaces) && SharedArchiveFile != NULL) {
4143     VerifySharedSpaces = true;
4144   }
4145 
4146   // Delay warning until here so that we've had a chance to process
4147   // the -XX:-PrintWarnings flag
4148   if (needs_hotspotrc_warning) {
4149     warning("%s file is present but has been ignored.  "
4150             "Run with -XX:Flags=%s to load the file.",
4151             hotspotrc, hotspotrc);
4152   }
4153 
4154 #ifdef _ALLBSD_SOURCE  // UseLargePages is not yet supported on BSD.
4155   UNSUPPORTED_OPTION(UseLargePages, "-XX:+UseLargePages");
4156 #endif
4157 
4158 #if INCLUDE_ALL_GCS
4159   #if (defined JAVASE_EMBEDDED || defined ARM)
4160     UNSUPPORTED_OPTION(UseG1GC, "G1 GC");
4161   #endif
4162 #endif
4163 
4164 #ifndef PRODUCT
4165   if (TraceBytecodesAt != 0) {
4166     TraceBytecodes = true;
4167   }
4168   if (CountCompiledCalls) {
4169     if (UseCounterDecay) {
4170       warning("UseCounterDecay disabled because CountCalls is set");
4171       UseCounterDecay = false;
4172     }
4173   }
4174 #endif // PRODUCT
4175 
4176   // JSR 292 is not supported before 1.7
4177   if (!JDK_Version::is_gte_jdk17x_version()) {
4178     if (EnableInvokeDynamic) {
4179       if (!FLAG_IS_DEFAULT(EnableInvokeDynamic)) {
4180         warning("JSR 292 is not supported before 1.7.  Disabling support.");
4181       }
4182       EnableInvokeDynamic = false;
4183     }
4184   }
4185 
4186   if (EnableInvokeDynamic && ScavengeRootsInCode == 0) {
4187     if (!FLAG_IS_DEFAULT(ScavengeRootsInCode)) {
4188       warning("forcing ScavengeRootsInCode non-zero because EnableInvokeDynamic is true");
4189     }
4190     ScavengeRootsInCode = 1;
4191   }
4192 
4193   if (PrintGCDetails) {
4194     // Turn on -verbose:gc options as well
4195     PrintGC = true;
4196   }
4197 
4198   if (!JDK_Version::is_gte_jdk18x_version()) {
4199     // To avoid changing the log format for 7 updates this flag is only
4200     // true by default in JDK8 and above.
4201     if (FLAG_IS_DEFAULT(PrintGCCause)) {
4202       FLAG_SET_DEFAULT(PrintGCCause, false);
4203     }
4204   }
4205 
4206   // Set object alignment values.
4207   set_object_alignment();
4208 
4209 #if !INCLUDE_ALL_GCS
4210   force_serial_gc();
4211 #endif // INCLUDE_ALL_GCS
4212 #if !INCLUDE_CDS
4213   if (DumpSharedSpaces || RequireSharedSpaces) {
4214     jio_fprintf(defaultStream::error_stream(),
4215       "Shared spaces are not supported in this VM\n");
4216     return JNI_ERR;
4217   }
4218   if ((UseSharedSpaces && FLAG_IS_CMDLINE(UseSharedSpaces)) || PrintSharedSpaces) {
4219     warning("Shared spaces are not supported in this VM");
4220     FLAG_SET_DEFAULT(UseSharedSpaces, false);
4221     FLAG_SET_DEFAULT(PrintSharedSpaces, false);
4222   }
4223   no_shared_spaces("CDS Disabled");
4224 #endif // INCLUDE_CDS
4225 
4226   return JNI_OK;
4227 }
4228 
4229 jint Arguments::apply_ergo() {
4230 
4231   // Set flags based on ergonomics.
4232   set_ergonomics_flags();
4233 
4234   set_shared_spaces_flags();
4235 
4236 #if defined(SPARC)
4237   // BIS instructions require 'membar' instruction regardless of the number
4238   // of CPUs because in virtualized/container environments which might use only 1
4239   // CPU, BIS instructions may produce incorrect results.
4240 
4241   if (FLAG_IS_DEFAULT(AssumeMP)) {
4242     FLAG_SET_DEFAULT(AssumeMP, true);
4243   }
4244 #endif
4245 
4246   // Check the GC selections again.
4247   if (!check_gc_consistency()) {
4248     return JNI_EINVAL;
4249   }
4250 
4251   if (TieredCompilation) {
4252     set_tiered_flags();
4253   } else {
4254     // Check if the policy is valid. Policies 0 and 1 are valid for non-tiered setup.
4255     if (CompilationPolicyChoice >= 2) {
4256       vm_exit_during_initialization(
4257         "Incompatible compilation policy selected", NULL);
4258     }
4259   }
4260   // Set NmethodSweepFraction after the size of the code cache is adapted (in case of tiered)
4261   if (FLAG_IS_DEFAULT(NmethodSweepFraction)) {
4262     FLAG_SET_DEFAULT(NmethodSweepFraction, 1 + ReservedCodeCacheSize / (16 * M));
4263   }
4264 
4265 
4266   // Set heap size based on available physical memory
4267   set_heap_size();
4268 
4269   ArgumentsExt::set_gc_specific_flags();
4270 
4271   // Initialize Metaspace flags and alignments.
4272   Metaspace::ergo_initialize();
4273 
4274   // Set bytecode rewriting flags
4275   set_bytecode_flags();
4276 
4277   // Set flags if Aggressive optimization flags (-XX:+AggressiveOpts) enabled.
4278   set_aggressive_opts_flags();
4279 
4280   // Turn off biased locking for locking debug mode flags,
4281   // which are subtlely different from each other but neither works with
4282   // biased locking.
4283   if (UseHeavyMonitors
4284 #ifdef COMPILER1
4285       || !UseFastLocking
4286 #endif // COMPILER1
4287     ) {
4288     if (!FLAG_IS_DEFAULT(UseBiasedLocking) && UseBiasedLocking) {
4289       // flag set to true on command line; warn the user that they
4290       // can't enable biased locking here
4291       warning("Biased Locking is not supported with locking debug flags"
4292               "; ignoring UseBiasedLocking flag." );
4293     }
4294     UseBiasedLocking = false;
4295   }
4296 
4297 #ifdef ZERO
4298   // Clear flags not supported on zero.
4299   FLAG_SET_DEFAULT(ProfileInterpreter, false);
4300   FLAG_SET_DEFAULT(UseBiasedLocking, false);
4301   LP64_ONLY(FLAG_SET_DEFAULT(UseCompressedOops, false));
4302   LP64_ONLY(FLAG_SET_DEFAULT(UseCompressedClassPointers, false));
4303 #endif // CC_INTERP
4304 
4305 #ifdef COMPILER2
4306   if (!EliminateLocks) {
4307     EliminateNestedLocks = false;
4308   }
4309   if (!Inline) {
4310     IncrementalInline = false;
4311   }
4312 #ifndef PRODUCT
4313   if (!IncrementalInline) {
4314     AlwaysIncrementalInline = false;
4315   }
4316 #endif
4317   if (IncrementalInline && FLAG_IS_DEFAULT(MaxNodeLimit)) {
4318     // incremental inlining: bump MaxNodeLimit
4319     FLAG_SET_DEFAULT(MaxNodeLimit, (intx)75000);
4320   }
4321   if (!UseTypeSpeculation && FLAG_IS_DEFAULT(TypeProfileLevel)) {
4322     // nothing to use the profiling, turn if off
4323     FLAG_SET_DEFAULT(TypeProfileLevel, 0);
4324   }
4325 #endif
4326 
4327   if (PrintAssembly && FLAG_IS_DEFAULT(DebugNonSafepoints)) {
4328     warning("PrintAssembly is enabled; turning on DebugNonSafepoints to gain additional output");
4329     DebugNonSafepoints = true;
4330   }
4331 
4332   if (FLAG_IS_CMDLINE(CompressedClassSpaceSize) && !UseCompressedClassPointers) {
4333     warning("Setting CompressedClassSpaceSize has no effect when compressed class pointers are not used");
4334   }
4335 
4336   if (UseOnStackReplacement && !UseLoopCounter) {
4337     warning("On-stack-replacement requires loop counters; enabling loop counters");
4338     FLAG_SET_DEFAULT(UseLoopCounter, true);
4339   }
4340 
4341 #ifndef PRODUCT
4342   if (CompileTheWorld) {
4343     // Force NmethodSweeper to sweep whole CodeCache each time.
4344     if (FLAG_IS_DEFAULT(NmethodSweepFraction)) {
4345       NmethodSweepFraction = 1;
4346     }
4347   }
4348 
4349   if (!LogVMOutput && FLAG_IS_DEFAULT(LogVMOutput)) {
4350     if (use_vm_log()) {
4351       LogVMOutput = true;
4352     }
4353   }
4354 #endif // PRODUCT
4355 
4356   if (PrintCommandLineFlags) {
4357     CommandLineFlags::printSetFlags(tty);
4358   }
4359 
4360   // Apply CPU specific policy for the BiasedLocking
4361   if (UseBiasedLocking) {
4362     if (!VM_Version::use_biased_locking() &&
4363         !(FLAG_IS_CMDLINE(UseBiasedLocking))) {
4364       UseBiasedLocking = false;
4365     }
4366   }
4367 #ifdef COMPILER2
4368   if (!UseBiasedLocking || EmitSync != 0) {
4369     UseOptoBiasInlining = false;
4370   }
4371 #endif
4372 
4373   // set PauseAtExit if the gamma launcher was used and a debugger is attached
4374   // but only if not already set on the commandline
4375   if (Arguments::created_by_gamma_launcher() && os::is_debugger_attached()) {
4376     bool set = false;
4377     CommandLineFlags::wasSetOnCmdline("PauseAtExit", &set);
4378     if (!set) {
4379       FLAG_SET_DEFAULT(PauseAtExit, true);
4380     }
4381   }
4382 
4383   return JNI_OK;
4384 }
4385 
4386 jint Arguments::adjust_after_os() {
4387   if (UseNUMA) {
4388     if (UseParallelGC || UseParallelOldGC) {
4389       if (FLAG_IS_DEFAULT(MinHeapDeltaBytes)) {
4390          FLAG_SET_DEFAULT(MinHeapDeltaBytes, 64*M);
4391       }
4392     }
4393     // UseNUMAInterleaving is set to ON for all collectors and
4394     // platforms when UseNUMA is set to ON. NUMA-aware collectors
4395     // such as the parallel collector for Linux and Solaris will
4396     // interleave old gen and survivor spaces on top of NUMA
4397     // allocation policy for the eden space.
4398     // Non NUMA-aware collectors such as CMS, G1 and Serial-GC on
4399     // all platforms and ParallelGC on Windows will interleave all
4400     // of the heap spaces across NUMA nodes.
4401     if (FLAG_IS_DEFAULT(UseNUMAInterleaving)) {
4402       FLAG_SET_ERGO(bool, UseNUMAInterleaving, true);
4403     }
4404   }
4405   return JNI_OK;
4406 }
4407 
4408 int Arguments::PropertyList_count(SystemProperty* pl) {
4409   int count = 0;
4410   while(pl != NULL) {
4411     count++;
4412     pl = pl->next();
4413   }
4414   return count;
4415 }
4416 
4417 const char* Arguments::PropertyList_get_value(SystemProperty *pl, const char* key) {
4418   assert(key != NULL, "just checking");
4419   SystemProperty* prop;
4420   for (prop = pl; prop != NULL; prop = prop->next()) {
4421     if (strcmp(key, prop->key()) == 0) return prop->value();
4422   }
4423   return NULL;
4424 }
4425 
4426 const char* Arguments::PropertyList_get_key_at(SystemProperty *pl, int index) {
4427   int count = 0;
4428   const char* ret_val = NULL;
4429 
4430   while(pl != NULL) {
4431     if(count >= index) {
4432       ret_val = pl->key();
4433       break;
4434     }
4435     count++;
4436     pl = pl->next();
4437   }
4438 
4439   return ret_val;
4440 }
4441 
4442 char* Arguments::PropertyList_get_value_at(SystemProperty* pl, int index) {
4443   int count = 0;
4444   char* ret_val = NULL;
4445 
4446   while(pl != NULL) {
4447     if(count >= index) {
4448       ret_val = pl->value();
4449       break;
4450     }
4451     count++;
4452     pl = pl->next();
4453   }
4454 
4455   return ret_val;
4456 }
4457 
4458 void Arguments::PropertyList_add(SystemProperty** plist, SystemProperty *new_p) {
4459   SystemProperty* p = *plist;
4460   if (p == NULL) {
4461     *plist = new_p;
4462   } else {
4463     while (p->next() != NULL) {
4464       p = p->next();
4465     }
4466     p->set_next(new_p);
4467   }
4468 }
4469 
4470 void Arguments::PropertyList_add(SystemProperty** plist, const char* k, char* v) {
4471   if (plist == NULL)
4472     return;
4473 
4474   SystemProperty* new_p = new SystemProperty(k, v, true);
4475   PropertyList_add(plist, new_p);
4476 }
4477 
4478 // This add maintains unique property key in the list.
4479 void Arguments::PropertyList_unique_add(SystemProperty** plist, const char* k, char* v, jboolean append) {
4480   if (plist == NULL)
4481     return;
4482 
4483   // If property key exist then update with new value.
4484   SystemProperty* prop;
4485   for (prop = *plist; prop != NULL; prop = prop->next()) {
4486     if (strcmp(k, prop->key()) == 0) {
4487       if (append) {
4488         prop->append_value(v);
4489       } else {
4490         prop->set_value(v);
4491       }
4492       return;
4493     }
4494   }
4495 
4496   PropertyList_add(plist, k, v);
4497 }
4498 
4499 // Copies src into buf, replacing "%%" with "%" and "%p" with pid
4500 // Returns true if all of the source pointed by src has been copied over to
4501 // the destination buffer pointed by buf. Otherwise, returns false.
4502 // Notes:
4503 // 1. If the length (buflen) of the destination buffer excluding the
4504 // NULL terminator character is not long enough for holding the expanded
4505 // pid characters, it also returns false instead of returning the partially
4506 // expanded one.
4507 // 2. The passed in "buflen" should be large enough to hold the null terminator.
4508 bool Arguments::copy_expand_pid(const char* src, size_t srclen,
4509                                 char* buf, size_t buflen) {
4510   const char* p = src;
4511   char* b = buf;
4512   const char* src_end = &src[srclen];
4513   char* buf_end = &buf[buflen - 1];
4514 
4515   while (p < src_end && b < buf_end) {
4516     if (*p == '%') {
4517       switch (*(++p)) {
4518       case '%':         // "%%" ==> "%"
4519         *b++ = *p++;
4520         break;
4521       case 'p':  {       //  "%p" ==> current process id
4522         // buf_end points to the character before the last character so
4523         // that we could write '\0' to the end of the buffer.
4524         size_t buf_sz = buf_end - b + 1;
4525         int ret = jio_snprintf(b, buf_sz, "%d", os::current_process_id());
4526 
4527         // if jio_snprintf fails or the buffer is not long enough to hold
4528         // the expanded pid, returns false.
4529         if (ret < 0 || ret >= (int)buf_sz) {
4530           return false;
4531         } else {
4532           b += ret;
4533           assert(*b == '\0', "fail in copy_expand_pid");
4534           if (p == src_end && b == buf_end + 1) {
4535             // reach the end of the buffer.
4536             return true;
4537           }
4538         }
4539         p++;
4540         break;
4541       }
4542       default :
4543         *b++ = '%';
4544       }
4545     } else {
4546       *b++ = *p++;
4547     }
4548   }
4549   *b = '\0';
4550   return (p == src_end); // return false if not all of the source was copied
4551 }