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Java example source code file (arguments.cpp)

This example Java source code file (arguments.cpp) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

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The arguments.cpp Java example source code

/*
 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

#include "precompiled.hpp"
#include "classfile/javaAssertions.hpp"
#include "classfile/symbolTable.hpp"
#include "compiler/compilerOracle.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/cardTableRS.hpp"
#include "memory/genCollectedHeap.hpp"
#include "memory/referenceProcessor.hpp"
#include "memory/universe.inline.hpp"
#include "oops/oop.inline.hpp"
#include "prims/jvmtiExport.hpp"
#include "runtime/arguments.hpp"
#include "runtime/globals_extension.hpp"
#include "runtime/java.hpp"
#include "services/management.hpp"
#include "services/memTracker.hpp"
#include "utilities/defaultStream.hpp"
#include "utilities/macros.hpp"
#include "utilities/taskqueue.hpp"
#ifdef TARGET_OS_FAMILY_linux
# include "os_linux.inline.hpp"
#endif
#ifdef TARGET_OS_FAMILY_solaris
# include "os_solaris.inline.hpp"
#endif
#ifdef TARGET_OS_FAMILY_windows
# include "os_windows.inline.hpp"
#endif
#ifdef TARGET_OS_FAMILY_bsd
# include "os_bsd.inline.hpp"
#endif
#if INCLUDE_ALL_GCS
#include "gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.hpp"
#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
#include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
#endif // INCLUDE_ALL_GCS

// Note: This is a special bug reporting site for the JVM
#define DEFAULT_VENDOR_URL_BUG "http://bugreport.sun.com/bugreport/crash.jsp"
#define DEFAULT_JAVA_LAUNCHER  "generic"

// Disable options not supported in this release, with a warning if they
// were explicitly requested on the command-line
#define UNSUPPORTED_OPTION(opt, description)                    \
do {                                                            \
  if (opt) {                                                    \
    if (FLAG_IS_CMDLINE(opt)) {                                 \
      warning(description " is disabled in this release.");     \
    }                                                           \
    FLAG_SET_DEFAULT(opt, false);                               \
  }                                                             \
} while(0)

#define UNSUPPORTED_GC_OPTION(gc)                                     \
do {                                                                  \
  if (gc) {                                                           \
    if (FLAG_IS_CMDLINE(gc)) {                                        \
      warning(#gc " is not supported in this VM.  Using Serial GC."); \
    }                                                                 \
    FLAG_SET_DEFAULT(gc, false);                                      \
  }                                                                   \
} while(0)

char**  Arguments::_jvm_flags_array             = NULL;
int     Arguments::_num_jvm_flags               = 0;
char**  Arguments::_jvm_args_array              = NULL;
int     Arguments::_num_jvm_args                = 0;
char*  Arguments::_java_command                 = NULL;
SystemProperty* Arguments::_system_properties   = NULL;
const char*  Arguments::_gc_log_filename        = NULL;
bool   Arguments::_has_profile                  = false;
size_t Arguments::_conservative_max_heap_alignment = 0;
uintx  Arguments::_min_heap_size                = 0;
Arguments::Mode Arguments::_mode                = _mixed;
bool   Arguments::_java_compiler                = false;
bool   Arguments::_xdebug_mode                  = false;
const char*  Arguments::_java_vendor_url_bug    = DEFAULT_VENDOR_URL_BUG;
const char*  Arguments::_sun_java_launcher      = DEFAULT_JAVA_LAUNCHER;
int    Arguments::_sun_java_launcher_pid        = -1;
bool   Arguments::_created_by_gamma_launcher    = false;

// These parameters are reset in method parse_vm_init_args(JavaVMInitArgs*)
bool   Arguments::_AlwaysCompileLoopMethods     = AlwaysCompileLoopMethods;
bool   Arguments::_UseOnStackReplacement        = UseOnStackReplacement;
bool   Arguments::_BackgroundCompilation        = BackgroundCompilation;
bool   Arguments::_ClipInlining                 = ClipInlining;

char*  Arguments::SharedArchivePath             = NULL;

AgentLibraryList Arguments::_libraryList;
AgentLibraryList Arguments::_agentList;

abort_hook_t     Arguments::_abort_hook         = NULL;
exit_hook_t      Arguments::_exit_hook          = NULL;
vfprintf_hook_t  Arguments::_vfprintf_hook      = NULL;


SystemProperty *Arguments::_java_ext_dirs = NULL;
SystemProperty *Arguments::_java_endorsed_dirs = NULL;
SystemProperty *Arguments::_sun_boot_library_path = NULL;
SystemProperty *Arguments::_java_library_path = NULL;
SystemProperty *Arguments::_java_home = NULL;
SystemProperty *Arguments::_java_class_path = NULL;
SystemProperty *Arguments::_sun_boot_class_path = NULL;

char* Arguments::_meta_index_path = NULL;
char* Arguments::_meta_index_dir = NULL;

// Check if head of 'option' matches 'name', and sets 'tail' remaining part of option string

static bool match_option(const JavaVMOption *option, const char* name,
                         const char** tail) {
  int len = (int)strlen(name);
  if (strncmp(option->optionString, name, len) == 0) {
    *tail = option->optionString + len;
    return true;
  } else {
    return false;
  }
}

static void logOption(const char* opt) {
  if (PrintVMOptions) {
    jio_fprintf(defaultStream::output_stream(), "VM option '%s'\n", opt);
  }
}

// Process java launcher properties.
void Arguments::process_sun_java_launcher_properties(JavaVMInitArgs* args) {
  // See if sun.java.launcher or sun.java.launcher.pid is defined.
  // Must do this before setting up other system properties,
  // as some of them may depend on launcher type.
  for (int index = 0; index < args->nOptions; index++) {
    const JavaVMOption* option = args->options + index;
    const char* tail;

    if (match_option(option, "-Dsun.java.launcher=", &tail)) {
      process_java_launcher_argument(tail, option->extraInfo);
      continue;
    }
    if (match_option(option, "-Dsun.java.launcher.pid=", &tail)) {
      _sun_java_launcher_pid = atoi(tail);
      continue;
    }
  }
}

// Initialize system properties key and value.
void Arguments::init_system_properties() {

  PropertyList_add(&_system_properties, new SystemProperty("java.vm.specification.name",
                                                                 "Java Virtual Machine Specification",  false));
  PropertyList_add(&_system_properties, new SystemProperty("java.vm.version", VM_Version::vm_release(),  false));
  PropertyList_add(&_system_properties, new SystemProperty("java.vm.name", VM_Version::vm_name(),  false));
  PropertyList_add(&_system_properties, new SystemProperty("java.vm.info", VM_Version::vm_info_string(),  true));

  // following are JVMTI agent writeable properties.
  // Properties values are set to NULL and they are
  // os specific they are initialized in os::init_system_properties_values().
  _java_ext_dirs = new SystemProperty("java.ext.dirs", NULL,  true);
  _java_endorsed_dirs = new SystemProperty("java.endorsed.dirs", NULL,  true);
  _sun_boot_library_path = new SystemProperty("sun.boot.library.path", NULL,  true);
  _java_library_path = new SystemProperty("java.library.path", NULL,  true);
  _java_home =  new SystemProperty("java.home", NULL,  true);
  _sun_boot_class_path = new SystemProperty("sun.boot.class.path", NULL,  true);

  _java_class_path = new SystemProperty("java.class.path", "",  true);

  // Add to System Property list.
  PropertyList_add(&_system_properties, _java_ext_dirs);
  PropertyList_add(&_system_properties, _java_endorsed_dirs);
  PropertyList_add(&_system_properties, _sun_boot_library_path);
  PropertyList_add(&_system_properties, _java_library_path);
  PropertyList_add(&_system_properties, _java_home);
  PropertyList_add(&_system_properties, _java_class_path);
  PropertyList_add(&_system_properties, _sun_boot_class_path);

  // Set OS specific system properties values
  os::init_system_properties_values();
}


  // Update/Initialize System properties after JDK version number is known
void Arguments::init_version_specific_system_properties() {
  enum { bufsz = 16 };
  char buffer[bufsz];
  const char* spec_vendor = "Sun Microsystems Inc.";
  uint32_t spec_version = 0;

  if (JDK_Version::is_gte_jdk17x_version()) {
    spec_vendor = "Oracle Corporation";
    spec_version = JDK_Version::current().major_version();
  }
  jio_snprintf(buffer, bufsz, "1." UINT32_FORMAT, spec_version);

  PropertyList_add(&_system_properties,
      new SystemProperty("java.vm.specification.vendor",  spec_vendor, false));
  PropertyList_add(&_system_properties,
      new SystemProperty("java.vm.specification.version", buffer, false));
  PropertyList_add(&_system_properties,
      new SystemProperty("java.vm.vendor", VM_Version::vm_vendor(),  false));
}

/**
 * Provide a slightly more user-friendly way of eliminating -XX flags.
 * When a flag is eliminated, it can be added to this list in order to
 * continue accepting this flag on the command-line, while issuing a warning
 * and ignoring the value.  Once the JDK version reaches the 'accept_until'
 * limit, we flatly refuse to admit the existence of the flag.  This allows
 * a flag to die correctly over JDK releases using HSX.
 */
typedef struct {
  const char* name;
  JDK_Version obsoleted_in; // when the flag went away
  JDK_Version accept_until; // which version to start denying the existence
} ObsoleteFlag;

static ObsoleteFlag obsolete_jvm_flags[] = {
  { "UseTrainGC",                    JDK_Version::jdk(5), JDK_Version::jdk(7) },
  { "UseSpecialLargeObjectHandling", JDK_Version::jdk(5), JDK_Version::jdk(7) },
  { "UseOversizedCarHandling",       JDK_Version::jdk(5), JDK_Version::jdk(7) },
  { "TraceCarAllocation",            JDK_Version::jdk(5), JDK_Version::jdk(7) },
  { "PrintTrainGCProcessingStats",   JDK_Version::jdk(5), JDK_Version::jdk(7) },
  { "LogOfCarSpaceSize",             JDK_Version::jdk(5), JDK_Version::jdk(7) },
  { "OversizedCarThreshold",         JDK_Version::jdk(5), JDK_Version::jdk(7) },
  { "MinTickInterval",               JDK_Version::jdk(5), JDK_Version::jdk(7) },
  { "DefaultTickInterval",           JDK_Version::jdk(5), JDK_Version::jdk(7) },
  { "MaxTickInterval",               JDK_Version::jdk(5), JDK_Version::jdk(7) },
  { "DelayTickAdjustment",           JDK_Version::jdk(5), JDK_Version::jdk(7) },
  { "ProcessingToTenuringRatio",     JDK_Version::jdk(5), JDK_Version::jdk(7) },
  { "MinTrainLength",                JDK_Version::jdk(5), JDK_Version::jdk(7) },
  { "AppendRatio",         JDK_Version::jdk_update(6,10), JDK_Version::jdk(7) },
  { "DefaultMaxRAM",       JDK_Version::jdk_update(6,18), JDK_Version::jdk(7) },
  { "DefaultInitialRAMFraction",
                           JDK_Version::jdk_update(6,18), JDK_Version::jdk(7) },
  { "UseDepthFirstScavengeOrder",
                           JDK_Version::jdk_update(6,22), JDK_Version::jdk(7) },
  { "HandlePromotionFailure",
                           JDK_Version::jdk_update(6,24), JDK_Version::jdk(8) },
  { "MaxLiveObjectEvacuationRatio",
                           JDK_Version::jdk_update(6,24), JDK_Version::jdk(8) },
  { "ForceSharedSpaces",   JDK_Version::jdk_update(6,25), JDK_Version::jdk(8) },
  { "UseParallelOldGCCompacting",
                           JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
  { "UseParallelDensePrefixUpdate",
                           JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
  { "UseParallelOldGCDensePrefix",
                           JDK_Version::jdk_update(6,27), JDK_Version::jdk(8) },
  { "AllowTransitionalJSR292",       JDK_Version::jdk(7), JDK_Version::jdk(8) },
  { "UseCompressedStrings",          JDK_Version::jdk(7), JDK_Version::jdk(8) },
  { "CMSPermGenPrecleaningEnabled", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
  { "CMSTriggerPermRatio", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
  { "CMSInitiatingPermOccupancyFraction", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
  { "AdaptivePermSizeWeight", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
  { "PermGenPadding", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
  { "PermMarkSweepDeadRatio", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
  { "PermSize", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
  { "MaxPermSize", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
  { "MinPermHeapExpansion", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
  { "MaxPermHeapExpansion", JDK_Version::jdk(8),  JDK_Version::jdk(9) },
  { "CMSRevisitStackSize",           JDK_Version::jdk(8), JDK_Version::jdk(9) },
  { "PrintRevisitStats",             JDK_Version::jdk(8), JDK_Version::jdk(9) },
  { "UseVectoredExceptions",         JDK_Version::jdk(8), JDK_Version::jdk(9) },
  { "UseSplitVerifier",              JDK_Version::jdk(8), JDK_Version::jdk(9) },
  { "UseISM",                        JDK_Version::jdk(8), JDK_Version::jdk(9) },
  { "UsePermISM",                    JDK_Version::jdk(8), JDK_Version::jdk(9) },
  { "UseMPSS",                       JDK_Version::jdk(8), JDK_Version::jdk(9) },
  { "UseStringCache",                JDK_Version::jdk(8), JDK_Version::jdk(9) },
#ifdef PRODUCT
  { "DesiredMethodLimit",
                           JDK_Version::jdk_update(7, 2), JDK_Version::jdk(8) },
#endif // PRODUCT
  { NULL, JDK_Version(0), JDK_Version(0) }
};

// Returns true if the flag is obsolete and fits into the range specified
// for being ignored.  In the case that the flag is ignored, the 'version'
// value is filled in with the version number when the flag became
// obsolete so that that value can be displayed to the user.
bool Arguments::is_newly_obsolete(const char *s, JDK_Version* version) {
  int i = 0;
  assert(version != NULL, "Must provide a version buffer");
  while (obsolete_jvm_flags[i].name != NULL) {
    const ObsoleteFlag& flag_status = obsolete_jvm_flags[i];
    // <flag>=xxx form
    // [-|+]<flag> form
    if ((strncmp(flag_status.name, s, strlen(flag_status.name)) == 0) ||
        ((s[0] == '+' || s[0] == '-') &&
        (strncmp(flag_status.name, &s[1], strlen(flag_status.name)) == 0))) {
      if (JDK_Version::current().compare(flag_status.accept_until) == -1) {
          *version = flag_status.obsoleted_in;
          return true;
      }
    }
    i++;
  }
  return false;
}

// Constructs the system class path (aka boot class path) from the following
// components, in order:
//
//     prefix           // from -Xbootclasspath/p:...
//     endorsed         // the expansion of -Djava.endorsed.dirs=...
//     base             // from os::get_system_properties() or -Xbootclasspath=
//     suffix           // from -Xbootclasspath/a:...
//
// java.endorsed.dirs is a list of directories; any jar or zip files in the
// directories are added to the sysclasspath just before the base.
//
// This could be AllStatic, but it isn't needed after argument processing is
// complete.
class SysClassPath: public StackObj {
public:
  SysClassPath(const char* base);
  ~SysClassPath();

  inline void set_base(const char* base);
  inline void add_prefix(const char* prefix);
  inline void add_suffix_to_prefix(const char* suffix);
  inline void add_suffix(const char* suffix);
  inline void reset_path(const char* base);

  // Expand the jar/zip files in each directory listed by the java.endorsed.dirs
  // property.  Must be called after all command-line arguments have been
  // processed (in particular, -Djava.endorsed.dirs=...) and before calling
  // combined_path().
  void expand_endorsed();

  inline const char* get_base()     const { return _items[_scp_base]; }
  inline const char* get_prefix()   const { return _items[_scp_prefix]; }
  inline const char* get_suffix()   const { return _items[_scp_suffix]; }
  inline const char* get_endorsed() const { return _items[_scp_endorsed]; }

  // Combine all the components into a single c-heap-allocated string; caller
  // must free the string if/when no longer needed.
  char* combined_path();

private:
  // Utility routines.
  static char* add_to_path(const char* path, const char* str, bool prepend);
  static char* add_jars_to_path(char* path, const char* directory);

  inline void reset_item_at(int index);

  // Array indices for the items that make up the sysclasspath.  All except the
  // base are allocated in the C heap and freed by this class.
  enum {
    _scp_prefix,        // from -Xbootclasspath/p:...
    _scp_endorsed,      // the expansion of -Djava.endorsed.dirs=...
    _scp_base,          // the default sysclasspath
    _scp_suffix,        // from -Xbootclasspath/a:...
    _scp_nitems         // the number of items, must be last.
  };

  const char* _items[_scp_nitems];
  DEBUG_ONLY(bool _expansion_done;)
};

SysClassPath::SysClassPath(const char* base) {
  memset(_items, 0, sizeof(_items));
  _items[_scp_base] = base;
  DEBUG_ONLY(_expansion_done = false;)
}

SysClassPath::~SysClassPath() {
  // Free everything except the base.
  for (int i = 0; i < _scp_nitems; ++i) {
    if (i != _scp_base) reset_item_at(i);
  }
  DEBUG_ONLY(_expansion_done = false;)
}

inline void SysClassPath::set_base(const char* base) {
  _items[_scp_base] = base;
}

inline void SysClassPath::add_prefix(const char* prefix) {
  _items[_scp_prefix] = add_to_path(_items[_scp_prefix], prefix, true);
}

inline void SysClassPath::add_suffix_to_prefix(const char* suffix) {
  _items[_scp_prefix] = add_to_path(_items[_scp_prefix], suffix, false);
}

inline void SysClassPath::add_suffix(const char* suffix) {
  _items[_scp_suffix] = add_to_path(_items[_scp_suffix], suffix, false);
}

inline void SysClassPath::reset_item_at(int index) {
  assert(index < _scp_nitems && index != _scp_base, "just checking");
  if (_items[index] != NULL) {
    FREE_C_HEAP_ARRAY(char, _items[index], mtInternal);
    _items[index] = NULL;
  }
}

inline void SysClassPath::reset_path(const char* base) {
  // Clear the prefix and suffix.
  reset_item_at(_scp_prefix);
  reset_item_at(_scp_suffix);
  set_base(base);
}

//------------------------------------------------------------------------------

void SysClassPath::expand_endorsed() {
  assert(_items[_scp_endorsed] == NULL, "can only be called once.");

  const char* path = Arguments::get_property("java.endorsed.dirs");
  if (path == NULL) {
    path = Arguments::get_endorsed_dir();
    assert(path != NULL, "no default for java.endorsed.dirs");
  }

  char* expanded_path = NULL;
  const char separator = *os::path_separator();
  const char* const end = path + strlen(path);
  while (path < end) {
    const char* tmp_end = strchr(path, separator);
    if (tmp_end == NULL) {
      expanded_path = add_jars_to_path(expanded_path, path);
      path = end;
    } else {
      char* dirpath = NEW_C_HEAP_ARRAY(char, tmp_end - path + 1, mtInternal);
      memcpy(dirpath, path, tmp_end - path);
      dirpath[tmp_end - path] = '\0';
      expanded_path = add_jars_to_path(expanded_path, dirpath);
      FREE_C_HEAP_ARRAY(char, dirpath, mtInternal);
      path = tmp_end + 1;
    }
  }
  _items[_scp_endorsed] = expanded_path;
  DEBUG_ONLY(_expansion_done = true;)
}

// Combine the bootclasspath elements, some of which may be null, into a single
// c-heap-allocated string.
char* SysClassPath::combined_path() {
  assert(_items[_scp_base] != NULL, "empty default sysclasspath");
  assert(_expansion_done, "must call expand_endorsed() first.");

  size_t lengths[_scp_nitems];
  size_t total_len = 0;

  const char separator = *os::path_separator();

  // Get the lengths.
  int i;
  for (i = 0; i < _scp_nitems; ++i) {
    if (_items[i] != NULL) {
      lengths[i] = strlen(_items[i]);
      // Include space for the separator char (or a NULL for the last item).
      total_len += lengths[i] + 1;
    }
  }
  assert(total_len > 0, "empty sysclasspath not allowed");

  // Copy the _items to a single string.
  char* cp = NEW_C_HEAP_ARRAY(char, total_len, mtInternal);
  char* cp_tmp = cp;
  for (i = 0; i < _scp_nitems; ++i) {
    if (_items[i] != NULL) {
      memcpy(cp_tmp, _items[i], lengths[i]);
      cp_tmp += lengths[i];
      *cp_tmp++ = separator;
    }
  }
  *--cp_tmp = '\0';     // Replace the extra separator.
  return cp;
}

// Note:  path must be c-heap-allocated (or NULL); it is freed if non-null.
char*
SysClassPath::add_to_path(const char* path, const char* str, bool prepend) {
  char *cp;

  assert(str != NULL, "just checking");
  if (path == NULL) {
    size_t len = strlen(str) + 1;
    cp = NEW_C_HEAP_ARRAY(char, len, mtInternal);
    memcpy(cp, str, len);                       // copy the trailing null
  } else {
    const char separator = *os::path_separator();
    size_t old_len = strlen(path);
    size_t str_len = strlen(str);
    size_t len = old_len + str_len + 2;

    if (prepend) {
      cp = NEW_C_HEAP_ARRAY(char, len, mtInternal);
      char* cp_tmp = cp;
      memcpy(cp_tmp, str, str_len);
      cp_tmp += str_len;
      *cp_tmp = separator;
      memcpy(++cp_tmp, path, old_len + 1);      // copy the trailing null
      FREE_C_HEAP_ARRAY(char, path, mtInternal);
    } else {
      cp = REALLOC_C_HEAP_ARRAY(char, path, len, mtInternal);
      char* cp_tmp = cp + old_len;
      *cp_tmp = separator;
      memcpy(++cp_tmp, str, str_len + 1);       // copy the trailing null
    }
  }
  return cp;
}

// Scan the directory and append any jar or zip files found to path.
// Note:  path must be c-heap-allocated (or NULL); it is freed if non-null.
char* SysClassPath::add_jars_to_path(char* path, const char* directory) {
  DIR* dir = os::opendir(directory);
  if (dir == NULL) return path;

  char dir_sep[2] = { '\0', '\0' };
  size_t directory_len = strlen(directory);
  const char fileSep = *os::file_separator();
  if (directory[directory_len - 1] != fileSep) dir_sep[0] = fileSep;

  /* Scan the directory for jars/zips, appending them to path. */
  struct dirent *entry;
  char *dbuf = NEW_C_HEAP_ARRAY(char, os::readdir_buf_size(directory), mtInternal);
  while ((entry = os::readdir(dir, (dirent *) dbuf)) != NULL) {
    const char* name = entry->d_name;
    const char* ext = name + strlen(name) - 4;
    bool isJarOrZip = ext > name &&
      (os::file_name_strcmp(ext, ".jar") == 0 ||
       os::file_name_strcmp(ext, ".zip") == 0);
    if (isJarOrZip) {
      char* jarpath = NEW_C_HEAP_ARRAY(char, directory_len + 2 + strlen(name), mtInternal);
      sprintf(jarpath, "%s%s%s", directory, dir_sep, name);
      path = add_to_path(path, jarpath, false);
      FREE_C_HEAP_ARRAY(char, jarpath, mtInternal);
    }
  }
  FREE_C_HEAP_ARRAY(char, dbuf, mtInternal);
  os::closedir(dir);
  return path;
}

// Parses a memory size specification string.
static bool atomull(const char *s, julong* result) {
  julong n = 0;
  int args_read = sscanf(s, JULONG_FORMAT, &n);
  if (args_read != 1) {
    return false;
  }
  while (*s != '\0' && isdigit(*s)) {
    s++;
  }
  // 4705540: illegal if more characters are found after the first non-digit
  if (strlen(s) > 1) {
    return false;
  }
  switch (*s) {
    case 'T': case 't':
      *result = n * G * K;
      // Check for overflow.
      if (*result/((julong)G * K) != n) return false;
      return true;
    case 'G': case 'g':
      *result = n * G;
      if (*result/G != n) return false;
      return true;
    case 'M': case 'm':
      *result = n * M;
      if (*result/M != n) return false;
      return true;
    case 'K': case 'k':
      *result = n * K;
      if (*result/K != n) return false;
      return true;
    case '\0':
      *result = n;
      return true;
    default:
      return false;
  }
}

Arguments::ArgsRange Arguments::check_memory_size(julong size, julong min_size) {
  if (size < min_size) return arg_too_small;
  // Check that size will fit in a size_t (only relevant on 32-bit)
  if (size > max_uintx) return arg_too_big;
  return arg_in_range;
}

// Describe an argument out of range error
void Arguments::describe_range_error(ArgsRange errcode) {
  switch(errcode) {
  case arg_too_big:
    jio_fprintf(defaultStream::error_stream(),
                "The specified size exceeds the maximum "
                "representable size.\n");
    break;
  case arg_too_small:
  case arg_unreadable:
  case arg_in_range:
    // do nothing for now
    break;
  default:
    ShouldNotReachHere();
  }
}

static bool set_bool_flag(char* name, bool value, Flag::Flags origin) {
  return CommandLineFlags::boolAtPut(name, &value, origin);
}

static bool set_fp_numeric_flag(char* name, char* value, Flag::Flags origin) {
  double v;
  if (sscanf(value, "%lf", &v) != 1) {
    return false;
  }

  if (CommandLineFlags::doubleAtPut(name, &v, origin)) {
    return true;
  }
  return false;
}

static bool set_numeric_flag(char* name, char* value, Flag::Flags origin) {
  julong v;
  intx intx_v;
  bool is_neg = false;
  // Check the sign first since atomull() parses only unsigned values.
  if (*value == '-') {
    if (!CommandLineFlags::intxAt(name, &intx_v)) {
      return false;
    }
    value++;
    is_neg = true;
  }
  if (!atomull(value, &v)) {
    return false;
  }
  intx_v = (intx) v;
  if (is_neg) {
    intx_v = -intx_v;
  }
  if (CommandLineFlags::intxAtPut(name, &intx_v, origin)) {
    return true;
  }
  uintx uintx_v = (uintx) v;
  if (!is_neg && CommandLineFlags::uintxAtPut(name, &uintx_v, origin)) {
    return true;
  }
  uint64_t uint64_t_v = (uint64_t) v;
  if (!is_neg && CommandLineFlags::uint64_tAtPut(name, &uint64_t_v, origin)) {
    return true;
  }
  return false;
}

static bool set_string_flag(char* name, const char* value, Flag::Flags origin) {
  if (!CommandLineFlags::ccstrAtPut(name, &value, origin))  return false;
  // Contract:  CommandLineFlags always returns a pointer that needs freeing.
  FREE_C_HEAP_ARRAY(char, value, mtInternal);
  return true;
}

static bool append_to_string_flag(char* name, const char* new_value, Flag::Flags origin) {
  const char* old_value = "";
  if (!CommandLineFlags::ccstrAt(name, &old_value))  return false;
  size_t old_len = old_value != NULL ? strlen(old_value) : 0;
  size_t new_len = strlen(new_value);
  const char* value;
  char* free_this_too = NULL;
  if (old_len == 0) {
    value = new_value;
  } else if (new_len == 0) {
    value = old_value;
  } else {
    char* buf = NEW_C_HEAP_ARRAY(char, old_len + 1 + new_len + 1, mtInternal);
    // each new setting adds another LINE to the switch:
    sprintf(buf, "%s\n%s", old_value, new_value);
    value = buf;
    free_this_too = buf;
  }
  (void) CommandLineFlags::ccstrAtPut(name, &value, origin);
  // CommandLineFlags always returns a pointer that needs freeing.
  FREE_C_HEAP_ARRAY(char, value, mtInternal);
  if (free_this_too != NULL) {
    // CommandLineFlags made its own copy, so I must delete my own temp. buffer.
    FREE_C_HEAP_ARRAY(char, free_this_too, mtInternal);
  }
  return true;
}

bool Arguments::parse_argument(const char* arg, Flag::Flags origin) {

  // range of acceptable characters spelled out for portability reasons
#define NAME_RANGE  "[abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_]"
#define BUFLEN 255
  char name[BUFLEN+1];
  char dummy;

  if (sscanf(arg, "-%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
    return set_bool_flag(name, false, origin);
  }
  if (sscanf(arg, "+%" XSTR(BUFLEN) NAME_RANGE "%c", name, &dummy) == 1) {
    return set_bool_flag(name, true, origin);
  }

  char punct;
  if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "%c", name, &punct) == 2 && punct == '=') {
    const char* value = strchr(arg, '=') + 1;
    Flag* flag = Flag::find_flag(name, strlen(name));
    if (flag != NULL && flag->is_ccstr()) {
      if (flag->ccstr_accumulates()) {
        return append_to_string_flag(name, value, origin);
      } else {
        if (value[0] == '\0') {
          value = NULL;
        }
        return set_string_flag(name, value, origin);
      }
    }
  }

  if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE ":%c", name, &punct) == 2 && punct == '=') {
    const char* value = strchr(arg, '=') + 1;
    // -XX:Foo:=xxx will reset the string flag to the given value.
    if (value[0] == '\0') {
      value = NULL;
    }
    return set_string_flag(name, value, origin);
  }

#define SIGNED_FP_NUMBER_RANGE "[-0123456789.]"
#define SIGNED_NUMBER_RANGE    "[-0123456789]"
#define        NUMBER_RANGE    "[0123456789]"
  char value[BUFLEN + 1];
  char value2[BUFLEN + 1];
  if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_NUMBER_RANGE "." "%" XSTR(BUFLEN) NUMBER_RANGE "%c", name, value, value2, &dummy) == 3) {
    // Looks like a floating-point number -- try again with more lenient format string
    if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) SIGNED_FP_NUMBER_RANGE "%c", name, value, &dummy) == 2) {
      return set_fp_numeric_flag(name, value, origin);
    }
  }

#define VALUE_RANGE "[-kmgtKMGT0123456789]"
  if (sscanf(arg, "%" XSTR(BUFLEN) NAME_RANGE "=" "%" XSTR(BUFLEN) VALUE_RANGE "%c", name, value, &dummy) == 2) {
    return set_numeric_flag(name, value, origin);
  }

  return false;
}

void Arguments::add_string(char*** bldarray, int* count, const char* arg) {
  assert(bldarray != NULL, "illegal argument");

  if (arg == NULL) {
    return;
  }

  int new_count = *count + 1;

  // expand the array and add arg to the last element
  if (*bldarray == NULL) {
    *bldarray = NEW_C_HEAP_ARRAY(char*, new_count, mtInternal);
  } else {
    *bldarray = REALLOC_C_HEAP_ARRAY(char*, *bldarray, new_count, mtInternal);
  }
  (*bldarray)[*count] = strdup(arg);
  *count = new_count;
}

void Arguments::build_jvm_args(const char* arg) {
  add_string(&_jvm_args_array, &_num_jvm_args, arg);
}

void Arguments::build_jvm_flags(const char* arg) {
  add_string(&_jvm_flags_array, &_num_jvm_flags, arg);
}

// utility function to return a string that concatenates all
// strings in a given char** array
const char* Arguments::build_resource_string(char** args, int count) {
  if (args == NULL || count == 0) {
    return NULL;
  }
  size_t length = strlen(args[0]) + 1; // add 1 for the null terminator
  for (int i = 1; i < count; i++) {
    length += strlen(args[i]) + 1; // add 1 for a space
  }
  char* s = NEW_RESOURCE_ARRAY(char, length);
  strcpy(s, args[0]);
  for (int j = 1; j < count; j++) {
    strcat(s, " ");
    strcat(s, args[j]);
  }
  return (const char*) s;
}

void Arguments::print_on(outputStream* st) {
  st->print_cr("VM Arguments:");
  if (num_jvm_flags() > 0) {
    st->print("jvm_flags: "); print_jvm_flags_on(st);
  }
  if (num_jvm_args() > 0) {
    st->print("jvm_args: "); print_jvm_args_on(st);
  }
  st->print_cr("java_command: %s", java_command() ? java_command() : "<unknown>");
  if (_java_class_path != NULL) {
    char* path = _java_class_path->value();
    st->print_cr("java_class_path (initial): %s", strlen(path) == 0 ? "<not set>" : path );
  }
  st->print_cr("Launcher Type: %s", _sun_java_launcher);
}

void Arguments::print_jvm_flags_on(outputStream* st) {
  if (_num_jvm_flags > 0) {
    for (int i=0; i < _num_jvm_flags; i++) {
      st->print("%s ", _jvm_flags_array[i]);
    }
    st->print_cr("");
  }
}

void Arguments::print_jvm_args_on(outputStream* st) {
  if (_num_jvm_args > 0) {
    for (int i=0; i < _num_jvm_args; i++) {
      st->print("%s ", _jvm_args_array[i]);
    }
    st->print_cr("");
  }
}

bool Arguments::process_argument(const char* arg,
    jboolean ignore_unrecognized, Flag::Flags origin) {

  JDK_Version since = JDK_Version();

  if (parse_argument(arg, origin) || ignore_unrecognized) {
    return true;
  }

  bool has_plus_minus = (*arg == '+' || *arg == '-');
  const char* const argname = has_plus_minus ? arg + 1 : arg;
  if (is_newly_obsolete(arg, &since)) {
    char version[256];
    since.to_string(version, sizeof(version));
    warning("ignoring option %s; support was removed in %s", argname, version);
    return true;
  }

  // For locked flags, report a custom error message if available.
  // Otherwise, report the standard unrecognized VM option.

  size_t arg_len;
  const char* equal_sign = strchr(argname, '=');
  if (equal_sign == NULL) {
    arg_len = strlen(argname);
  } else {
    arg_len = equal_sign - argname;
  }

  Flag* found_flag = Flag::find_flag((const char*)argname, arg_len, true);
  if (found_flag != NULL) {
    char locked_message_buf[BUFLEN];
    found_flag->get_locked_message(locked_message_buf, BUFLEN);
    if (strlen(locked_message_buf) == 0) {
      if (found_flag->is_bool() && !has_plus_minus) {
        jio_fprintf(defaultStream::error_stream(),
          "Missing +/- setting for VM option '%s'\n", argname);
      } else if (!found_flag->is_bool() && has_plus_minus) {
        jio_fprintf(defaultStream::error_stream(),
          "Unexpected +/- setting in VM option '%s'\n", argname);
      } else {
        jio_fprintf(defaultStream::error_stream(),
          "Improperly specified VM option '%s'\n", argname);
      }
    } else {
      jio_fprintf(defaultStream::error_stream(), "%s", locked_message_buf);
    }
  } else {
    jio_fprintf(defaultStream::error_stream(),
                "Unrecognized VM option '%s'\n", argname);
    Flag* fuzzy_matched = Flag::fuzzy_match((const char*)argname, arg_len, true);
    if (fuzzy_matched != NULL) {
      jio_fprintf(defaultStream::error_stream(),
                  "Did you mean '%s%s%s'?\n",
                  (fuzzy_matched->is_bool()) ? "(+/-)" : "",
                  fuzzy_matched->_name,
                  (fuzzy_matched->is_bool()) ? "" : "=<value>");
    }
  }

  // allow for commandline "commenting out" options like -XX:#+Verbose
  return arg[0] == '#';
}

bool Arguments::process_settings_file(const char* file_name, bool should_exist, jboolean ignore_unrecognized) {
  FILE* stream = fopen(file_name, "rb");
  if (stream == NULL) {
    if (should_exist) {
      jio_fprintf(defaultStream::error_stream(),
                  "Could not open settings file %s\n", file_name);
      return false;
    } else {
      return true;
    }
  }

  char token[1024];
  int  pos = 0;

  bool in_white_space = true;
  bool in_comment     = false;
  bool in_quote       = false;
  char quote_c        = 0;
  bool result         = true;

  int c = getc(stream);
  while(c != EOF && pos < (int)(sizeof(token)-1)) {
    if (in_white_space) {
      if (in_comment) {
        if (c == '\n') in_comment = false;
      } else {
        if (c == '#') in_comment = true;
        else if (!isspace(c)) {
          in_white_space = false;
          token[pos++] = c;
        }
      }
    } else {
      if (c == '\n' || (!in_quote && isspace(c))) {
        // token ends at newline, or at unquoted whitespace
        // this allows a way to include spaces in string-valued options
        token[pos] = '\0';
        logOption(token);
        result &= process_argument(token, ignore_unrecognized, Flag::CONFIG_FILE);
        build_jvm_flags(token);
        pos = 0;
        in_white_space = true;
        in_quote = false;
      } else if (!in_quote && (c == '\'' || c == '"')) {
        in_quote = true;
        quote_c = c;
      } else if (in_quote && (c == quote_c)) {
        in_quote = false;
      } else {
        token[pos++] = c;
      }
    }
    c = getc(stream);
  }
  if (pos > 0) {
    token[pos] = '\0';
    result &= process_argument(token, ignore_unrecognized, Flag::CONFIG_FILE);
    build_jvm_flags(token);
  }
  fclose(stream);
  return result;
}

//=============================================================================================================
// Parsing of properties (-D)

const char* Arguments::get_property(const char* key) {
  return PropertyList_get_value(system_properties(), key);
}

bool Arguments::add_property(const char* prop) {
  const char* eq = strchr(prop, '=');
  char* key;
  // ns must be static--its address may be stored in a SystemProperty object.
  const static char ns[1] = {0};
  char* value = (char *)ns;

  size_t key_len = (eq == NULL) ? strlen(prop) : (eq - prop);
  key = AllocateHeap(key_len + 1, mtInternal);
  strncpy(key, prop, key_len);
  key[key_len] = '\0';

  if (eq != NULL) {
    size_t value_len = strlen(prop) - key_len - 1;
    value = AllocateHeap(value_len + 1, mtInternal);
    strncpy(value, &prop[key_len + 1], value_len + 1);
  }

  if (strcmp(key, "java.compiler") == 0) {
    process_java_compiler_argument(value);
    FreeHeap(key);
    if (eq != NULL) {
      FreeHeap(value);
    }
    return true;
  } else if (strcmp(key, "sun.java.command") == 0) {
    _java_command = value;

    // Record value in Arguments, but let it get passed to Java.
  } else if (strcmp(key, "sun.java.launcher.pid") == 0) {
    // launcher.pid property is private and is processed
    // in process_sun_java_launcher_properties();
    // the sun.java.launcher property is passed on to the java application
    FreeHeap(key);
    if (eq != NULL) {
      FreeHeap(value);
    }
    return true;
  } else if (strcmp(key, "java.vendor.url.bug") == 0) {
    // save it in _java_vendor_url_bug, so JVM fatal error handler can access
    // its value without going through the property list or making a Java call.
    _java_vendor_url_bug = value;
  } else if (strcmp(key, "sun.boot.library.path") == 0) {
    PropertyList_unique_add(&_system_properties, key, value, true);
    return true;
  }
  // Create new property and add at the end of the list
  PropertyList_unique_add(&_system_properties, key, value);
  return true;
}

//===========================================================================================================
// Setting int/mixed/comp mode flags

void Arguments::set_mode_flags(Mode mode) {
  // Set up default values for all flags.
  // If you add a flag to any of the branches below,
  // add a default value for it here.
  set_java_compiler(false);
  _mode                      = mode;

  // Ensure Agent_OnLoad has the correct initial values.
  // This may not be the final mode; mode may change later in onload phase.
  PropertyList_unique_add(&_system_properties, "java.vm.info",
                          (char*)VM_Version::vm_info_string(), false);

  UseInterpreter             = true;
  UseCompiler                = true;
  UseLoopCounter             = true;

#ifndef ZERO
  // Turn these off for mixed and comp.  Leave them on for Zero.
  if (FLAG_IS_DEFAULT(UseFastAccessorMethods)) {
    UseFastAccessorMethods = (mode == _int);
  }
  if (FLAG_IS_DEFAULT(UseFastEmptyMethods)) {
    UseFastEmptyMethods = (mode == _int);
  }
#endif

  // Default values may be platform/compiler dependent -
  // use the saved values
  ClipInlining               = Arguments::_ClipInlining;
  AlwaysCompileLoopMethods   = Arguments::_AlwaysCompileLoopMethods;
  UseOnStackReplacement      = Arguments::_UseOnStackReplacement;
  BackgroundCompilation      = Arguments::_BackgroundCompilation;

  // Change from defaults based on mode
  switch (mode) {
  default:
    ShouldNotReachHere();
    break;
  case _int:
    UseCompiler              = false;
    UseLoopCounter           = false;
    AlwaysCompileLoopMethods = false;
    UseOnStackReplacement    = false;
    break;
  case _mixed:
    // same as default
    break;
  case _comp:
    UseInterpreter           = false;
    BackgroundCompilation    = false;
    ClipInlining             = false;
    // Be much more aggressive in tiered mode with -Xcomp and exercise C2 more.
    // We will first compile a level 3 version (C1 with full profiling), then do one invocation of it and
    // compile a level 4 (C2) and then continue executing it.
    if (TieredCompilation) {
      Tier3InvokeNotifyFreqLog = 0;
      Tier4InvocationThreshold = 0;
    }
    break;
  }
}

#if defined(COMPILER2) || defined(_LP64) || !INCLUDE_CDS
// Conflict: required to use shared spaces (-Xshare:on), but
// incompatible command line options were chosen.

static void no_shared_spaces() {
  if (RequireSharedSpaces) {
    jio_fprintf(defaultStream::error_stream(),
      "Class data sharing is inconsistent with other specified options.\n");
    vm_exit_during_initialization("Unable to use shared archive.", NULL);
  } else {
    FLAG_SET_DEFAULT(UseSharedSpaces, false);
  }
}
#endif

void Arguments::set_tiered_flags() {
  // With tiered, set default policy to AdvancedThresholdPolicy, which is 3.
  if (FLAG_IS_DEFAULT(CompilationPolicyChoice)) {
    FLAG_SET_DEFAULT(CompilationPolicyChoice, 3);
  }
  if (CompilationPolicyChoice < 2) {
    vm_exit_during_initialization(
      "Incompatible compilation policy selected", NULL);
  }
  // Increase the code cache size - tiered compiles a lot more.
  if (FLAG_IS_DEFAULT(ReservedCodeCacheSize)) {
    FLAG_SET_DEFAULT(ReservedCodeCacheSize, ReservedCodeCacheSize * 5);
  }
  if (!UseInterpreter) { // -Xcomp
    Tier3InvokeNotifyFreqLog = 0;
    Tier4InvocationThreshold = 0;
  }
}

#if INCLUDE_ALL_GCS
static void disable_adaptive_size_policy(const char* collector_name) {
  if (UseAdaptiveSizePolicy) {
    if (FLAG_IS_CMDLINE(UseAdaptiveSizePolicy)) {
      warning("disabling UseAdaptiveSizePolicy; it is incompatible with %s.",
              collector_name);
    }
    FLAG_SET_DEFAULT(UseAdaptiveSizePolicy, false);
  }
}

void Arguments::set_parnew_gc_flags() {
  assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC && !UseG1GC,
         "control point invariant");
  assert(UseParNewGC, "Error");

  // Turn off AdaptiveSizePolicy for parnew until it is complete.
  disable_adaptive_size_policy("UseParNewGC");

  if (FLAG_IS_DEFAULT(ParallelGCThreads)) {
    FLAG_SET_DEFAULT(ParallelGCThreads, Abstract_VM_Version::parallel_worker_threads());
    assert(ParallelGCThreads > 0, "We should always have at least one thread by default");
  } else if (ParallelGCThreads == 0) {
    jio_fprintf(defaultStream::error_stream(),
        "The ParNew GC can not be combined with -XX:ParallelGCThreads=0\n");
    vm_exit(1);
  }

  // By default YoungPLABSize and OldPLABSize are set to 4096 and 1024 respectively,
  // these settings are default for Parallel Scavenger. For ParNew+Tenured configuration
  // we set them to 1024 and 1024.
  // See CR 6362902.
  if (FLAG_IS_DEFAULT(YoungPLABSize)) {
    FLAG_SET_DEFAULT(YoungPLABSize, (intx)1024);
  }
  if (FLAG_IS_DEFAULT(OldPLABSize)) {
    FLAG_SET_DEFAULT(OldPLABSize, (intx)1024);
  }

  // AlwaysTenure flag should make ParNew promote all at first collection.
  // See CR 6362902.
  if (AlwaysTenure) {
    FLAG_SET_CMDLINE(uintx, MaxTenuringThreshold, 0);
  }
  // When using compressed oops, we use local overflow stacks,
  // rather than using a global overflow list chained through
  // the klass word of the object's pre-image.
  if (UseCompressedOops && !ParGCUseLocalOverflow) {
    if (!FLAG_IS_DEFAULT(ParGCUseLocalOverflow)) {
      warning("Forcing +ParGCUseLocalOverflow: needed if using compressed references");
    }
    FLAG_SET_DEFAULT(ParGCUseLocalOverflow, true);
  }
  assert(ParGCUseLocalOverflow || !UseCompressedOops, "Error");
}

// Adjust some sizes to suit CMS and/or ParNew needs; these work well on
// sparc/solaris for certain applications, but would gain from
// further optimization and tuning efforts, and would almost
// certainly gain from analysis of platform and environment.
void Arguments::set_cms_and_parnew_gc_flags() {
  assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC, "Error");
  assert(UseConcMarkSweepGC, "CMS is expected to be on here");

  // If we are using CMS, we prefer to UseParNewGC,
  // unless explicitly forbidden.
  if (FLAG_IS_DEFAULT(UseParNewGC)) {
    FLAG_SET_ERGO(bool, UseParNewGC, true);
  }

  // Turn off AdaptiveSizePolicy by default for cms until it is complete.
  disable_adaptive_size_policy("UseConcMarkSweepGC");

  // In either case, adjust ParallelGCThreads and/or UseParNewGC
  // as needed.
  if (UseParNewGC) {
    set_parnew_gc_flags();
  }

  size_t max_heap = align_size_down(MaxHeapSize,
                                    CardTableRS::ct_max_alignment_constraint());

  // Now make adjustments for CMS
  intx   tenuring_default = (intx)6;
  size_t young_gen_per_worker = CMSYoungGenPerWorker;

  // Preferred young gen size for "short" pauses:
  // upper bound depends on # of threads and NewRatio.
  const uintx parallel_gc_threads =
    (ParallelGCThreads == 0 ? 1 : ParallelGCThreads);
  const size_t preferred_max_new_size_unaligned =
    MIN2(max_heap/(NewRatio+1), ScaleForWordSize(young_gen_per_worker * parallel_gc_threads));
  size_t preferred_max_new_size =
    align_size_up(preferred_max_new_size_unaligned, os::vm_page_size());

  // Unless explicitly requested otherwise, size young gen
  // for "short" pauses ~ CMSYoungGenPerWorker*ParallelGCThreads

  // If either MaxNewSize or NewRatio is set on the command line,
  // assume the user is trying to set the size of the young gen.
  if (FLAG_IS_DEFAULT(MaxNewSize) && FLAG_IS_DEFAULT(NewRatio)) {

    // Set MaxNewSize to our calculated preferred_max_new_size unless
    // NewSize was set on the command line and it is larger than
    // preferred_max_new_size.
    if (!FLAG_IS_DEFAULT(NewSize)) {   // NewSize explicitly set at command-line
      FLAG_SET_ERGO(uintx, MaxNewSize, MAX2(NewSize, preferred_max_new_size));
    } else {
      FLAG_SET_ERGO(uintx, MaxNewSize, preferred_max_new_size);
    }
    if (PrintGCDetails && Verbose) {
      // Too early to use gclog_or_tty
      tty->print_cr("CMS ergo set MaxNewSize: " SIZE_FORMAT, MaxNewSize);
    }

    // Code along this path potentially sets NewSize and OldSize
    if (PrintGCDetails && Verbose) {
      // Too early to use gclog_or_tty
      tty->print_cr("CMS set min_heap_size: " SIZE_FORMAT
           " initial_heap_size:  " SIZE_FORMAT
           " max_heap: " SIZE_FORMAT,
           min_heap_size(), InitialHeapSize, max_heap);
    }
    size_t min_new = preferred_max_new_size;
    if (FLAG_IS_CMDLINE(NewSize)) {
      min_new = NewSize;
    }
    if (max_heap > min_new && min_heap_size() > min_new) {
      // Unless explicitly requested otherwise, make young gen
      // at least min_new, and at most preferred_max_new_size.
      if (FLAG_IS_DEFAULT(NewSize)) {
        FLAG_SET_ERGO(uintx, NewSize, MAX2(NewSize, min_new));
        FLAG_SET_ERGO(uintx, NewSize, MIN2(preferred_max_new_size, NewSize));
        if (PrintGCDetails && Verbose) {
          // Too early to use gclog_or_tty
          tty->print_cr("CMS ergo set NewSize: " SIZE_FORMAT, NewSize);
        }
      }
      // Unless explicitly requested otherwise, size old gen
      // so it's NewRatio x of NewSize.
      if (FLAG_IS_DEFAULT(OldSize)) {
        if (max_heap > NewSize) {
          FLAG_SET_ERGO(uintx, OldSize, MIN2(NewRatio*NewSize, max_heap - NewSize));
          if (PrintGCDetails && Verbose) {
            // Too early to use gclog_or_tty
            tty->print_cr("CMS ergo set OldSize: " SIZE_FORMAT, OldSize);
          }
        }
      }
    }
  }
  // Unless explicitly requested otherwise, definitely
  // promote all objects surviving "tenuring_default" scavenges.
  if (FLAG_IS_DEFAULT(MaxTenuringThreshold) &&
      FLAG_IS_DEFAULT(SurvivorRatio)) {
    FLAG_SET_ERGO(uintx, MaxTenuringThreshold, tenuring_default);
  }
  // If we decided above (or user explicitly requested)
  // `promote all' (via MaxTenuringThreshold := 0),
  // prefer minuscule survivor spaces so as not to waste
  // space for (non-existent) survivors
  if (FLAG_IS_DEFAULT(SurvivorRatio) && MaxTenuringThreshold == 0) {
    FLAG_SET_ERGO(uintx, SurvivorRatio, MAX2((uintx)1024, SurvivorRatio));
  }
  // If OldPLABSize is set and CMSParPromoteBlocksToClaim is not,
  // set CMSParPromoteBlocksToClaim equal to OldPLABSize.
  // This is done in order to make ParNew+CMS configuration to work
  // with YoungPLABSize and OldPLABSize options.
  // See CR 6362902.
  if (!FLAG_IS_DEFAULT(OldPLABSize)) {
    if (FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim)) {
      // OldPLABSize is not the default value but CMSParPromoteBlocksToClaim
      // is.  In this situtation let CMSParPromoteBlocksToClaim follow
      // the value (either from the command line or ergonomics) of
      // OldPLABSize.  Following OldPLABSize is an ergonomics decision.
      FLAG_SET_ERGO(uintx, CMSParPromoteBlocksToClaim, OldPLABSize);
    } else {
      // OldPLABSize and CMSParPromoteBlocksToClaim are both set.
      // CMSParPromoteBlocksToClaim is a collector-specific flag, so
      // we'll let it to take precedence.
      jio_fprintf(defaultStream::error_stream(),
                  "Both OldPLABSize and CMSParPromoteBlocksToClaim"
                  " options are specified for the CMS collector."
                  " CMSParPromoteBlocksToClaim will take precedence.\n");
    }
  }
  if (!FLAG_IS_DEFAULT(ResizeOldPLAB) && !ResizeOldPLAB) {
    // OldPLAB sizing manually turned off: Use a larger default setting,
    // unless it was manually specified. This is because a too-low value
    // will slow down scavenges.
    if (FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim)) {
      FLAG_SET_ERGO(uintx, CMSParPromoteBlocksToClaim, 50); // default value before 6631166
    }
  }
  // Overwrite OldPLABSize which is the variable we will internally use everywhere.
  FLAG_SET_ERGO(uintx, OldPLABSize, CMSParPromoteBlocksToClaim);
  // If either of the static initialization defaults have changed, note this
  // modification.
  if (!FLAG_IS_DEFAULT(CMSParPromoteBlocksToClaim) || !FLAG_IS_DEFAULT(OldPLABWeight)) {
    CFLS_LAB::modify_initialization(OldPLABSize, OldPLABWeight);
  }
  if (PrintGCDetails && Verbose) {
    tty->print_cr("MarkStackSize: %uk  MarkStackSizeMax: %uk",
      MarkStackSize / K, MarkStackSizeMax / K);
    tty->print_cr("ConcGCThreads: %u", ConcGCThreads);
  }
}
#endif // INCLUDE_ALL_GCS

void set_object_alignment() {
  // Object alignment.
  assert(is_power_of_2(ObjectAlignmentInBytes), "ObjectAlignmentInBytes must be power of 2");
  MinObjAlignmentInBytes     = ObjectAlignmentInBytes;
  assert(MinObjAlignmentInBytes >= HeapWordsPerLong * HeapWordSize, "ObjectAlignmentInBytes value is too small");
  MinObjAlignment            = MinObjAlignmentInBytes / HeapWordSize;
  assert(MinObjAlignmentInBytes == MinObjAlignment * HeapWordSize, "ObjectAlignmentInBytes value is incorrect");
  MinObjAlignmentInBytesMask = MinObjAlignmentInBytes - 1;

  LogMinObjAlignmentInBytes  = exact_log2(ObjectAlignmentInBytes);
  LogMinObjAlignment         = LogMinObjAlignmentInBytes - LogHeapWordSize;

  // Oop encoding heap max
  OopEncodingHeapMax = (uint64_t(max_juint) + 1) << LogMinObjAlignmentInBytes;

#if INCLUDE_ALL_GCS
  // Set CMS global values
  CompactibleFreeListSpace::set_cms_values();
#endif // INCLUDE_ALL_GCS
}

bool verify_object_alignment() {
  // Object alignment.
  if (!is_power_of_2(ObjectAlignmentInBytes)) {
    jio_fprintf(defaultStream::error_stream(),
                "error: ObjectAlignmentInBytes=%d must be power of 2\n",
                (int)ObjectAlignmentInBytes);
    return false;
  }
  if ((int)ObjectAlignmentInBytes < BytesPerLong) {
    jio_fprintf(defaultStream::error_stream(),
                "error: ObjectAlignmentInBytes=%d must be greater or equal %d\n",
                (int)ObjectAlignmentInBytes, BytesPerLong);
    return false;
  }
  // It does not make sense to have big object alignment
  // since a space lost due to alignment will be greater
  // then a saved space from compressed oops.
  if ((int)ObjectAlignmentInBytes > 256) {
    jio_fprintf(defaultStream::error_stream(),
                "error: ObjectAlignmentInBytes=%d must not be greater than 256\n",
                (int)ObjectAlignmentInBytes);
    return false;
  }
  // In case page size is very small.
  if ((int)ObjectAlignmentInBytes >= os::vm_page_size()) {
    jio_fprintf(defaultStream::error_stream(),
                "error: ObjectAlignmentInBytes=%d must be less than page size %d\n",
                (int)ObjectAlignmentInBytes, os::vm_page_size());
    return false;
  }
  return true;
}

uintx Arguments::max_heap_for_compressed_oops() {
  // Avoid sign flip.
  assert(OopEncodingHeapMax > (uint64_t)os::vm_page_size(), "Unusual page size");
  // We need to fit both the NULL page and the heap into the memory budget, while
  // keeping alignment constraints of the heap. To guarantee the latter, as the
  // NULL page is located before the heap, we pad the NULL page to the conservative
  // maximum alignment that the GC may ever impose upon the heap.
  size_t displacement_due_to_null_page = align_size_up_(os::vm_page_size(),
                                                        _conservative_max_heap_alignment);

  LP64_ONLY(return OopEncodingHeapMax - displacement_due_to_null_page);
  NOT_LP64(ShouldNotReachHere(); return 0);
}

bool Arguments::should_auto_select_low_pause_collector() {
  if (UseAutoGCSelectPolicy &&
      !FLAG_IS_DEFAULT(MaxGCPauseMillis) &&
      (MaxGCPauseMillis <= AutoGCSelectPauseMillis)) {
    if (PrintGCDetails) {
      // Cannot use gclog_or_tty yet.
      tty->print_cr("Automatic selection of the low pause collector"
       " based on pause goal of %d (ms)", MaxGCPauseMillis);
    }
    return true;
  }
  return false;
}

void Arguments::set_use_compressed_oops() {
#ifndef ZERO
#ifdef _LP64
  // MaxHeapSize is not set up properly at this point, but
  // the only value that can override MaxHeapSize if we are
  // to use UseCompressedOops is InitialHeapSize.
  size_t max_heap_size = MAX2(MaxHeapSize, InitialHeapSize);

  if (max_heap_size <= max_heap_for_compressed_oops()) {
#if !defined(COMPILER1) || defined(TIERED)
    if (FLAG_IS_DEFAULT(UseCompressedOops)) {
      FLAG_SET_ERGO(bool, UseCompressedOops, true);
    }
#endif
#ifdef _WIN64
    if (UseLargePages && UseCompressedOops) {
      // Cannot allocate guard pages for implicit checks in indexed addressing
      // mode, when large pages are specified on windows.
      // This flag could be switched ON if narrow oop base address is set to 0,
      // see code in Universe::initialize_heap().
      Universe::set_narrow_oop_use_implicit_null_checks(false);
    }
#endif //  _WIN64
  } else {
    if (UseCompressedOops && !FLAG_IS_DEFAULT(UseCompressedOops)) {
      warning("Max heap size too large for Compressed Oops");
      FLAG_SET_DEFAULT(UseCompressedOops, false);
      FLAG_SET_DEFAULT(UseCompressedClassPointers, false);
    }
  }
#endif // _LP64
#endif // ZERO
}


// NOTE: set_use_compressed_klass_ptrs() must be called after calling
// set_use_compressed_oops().
void Arguments::set_use_compressed_klass_ptrs() {
#ifndef ZERO
#ifdef _LP64
  // UseCompressedOops must be on for UseCompressedClassPointers to be on.
  if (!UseCompressedOops) {
    if (UseCompressedClassPointers) {
      warning("UseCompressedClassPointers requires UseCompressedOops");
    }
    FLAG_SET_DEFAULT(UseCompressedClassPointers, false);
  } else {
    // Turn on UseCompressedClassPointers too
    if (FLAG_IS_DEFAULT(UseCompressedClassPointers)) {
      FLAG_SET_ERGO(bool, UseCompressedClassPointers, true);
    }
    // Check the CompressedClassSpaceSize to make sure we use compressed klass ptrs.
    if (UseCompressedClassPointers) {
      if (CompressedClassSpaceSize > KlassEncodingMetaspaceMax) {
        warning("CompressedClassSpaceSize is too large for UseCompressedClassPointers");
        FLAG_SET_DEFAULT(UseCompressedClassPointers, false);
      }
    }
  }
#endif // _LP64
#endif // !ZERO
}

void Arguments::set_conservative_max_heap_alignment() {
  // The conservative maximum required alignment for the heap is the maximum of
  // the alignments imposed by several sources: any requirements from the heap
  // itself, the collector policy and the maximum page size we may run the VM
  // with.
  size_t heap_alignment = GenCollectedHeap::conservative_max_heap_alignment();
#if INCLUDE_ALL_GCS
  if (UseParallelGC) {
    heap_alignment = ParallelScavengeHeap::conservative_max_heap_alignment();
  } else if (UseG1GC) {
    heap_alignment = G1CollectedHeap::conservative_max_heap_alignment();
  }
#endif // INCLUDE_ALL_GCS
  _conservative_max_heap_alignment = MAX3(heap_alignment, os::max_page_size(),
    CollectorPolicy::compute_heap_alignment());
}

void Arguments::set_ergonomics_flags() {

  if (os::is_server_class_machine()) {
    // If no other collector is requested explicitly,
    // let the VM select the collector based on
    // machine class and automatic selection policy.
    if (!UseSerialGC &&
        !UseConcMarkSweepGC &&
        !UseG1GC &&
        !UseParNewGC &&
        FLAG_IS_DEFAULT(UseParallelGC)) {
      if (should_auto_select_low_pause_collector()) {
        FLAG_SET_ERGO(bool, UseConcMarkSweepGC, true);
      } else {
        FLAG_SET_ERGO(bool, UseParallelGC, true);
      }
    }
  }
#ifdef COMPILER2
  // Shared spaces work fine with other GCs but causes bytecode rewriting
  // to be disabled, which hurts interpreter performance and decreases
  // server performance.  When -server is specified, keep the default off
  // unless it is asked for.  Future work: either add bytecode rewriting
  // at link time, or rewrite bytecodes in non-shared methods.
  if (!DumpSharedSpaces && !RequireSharedSpaces &&
      (FLAG_IS_DEFAULT(UseSharedSpaces) || !UseSharedSpaces)) {
    no_shared_spaces();
  }
#endif

  set_conservative_max_heap_alignment();

#ifndef ZERO
#ifdef _LP64
  set_use_compressed_oops();

  // set_use_compressed_klass_ptrs() must be called after calling
  // set_use_compressed_oops().
  set_use_compressed_klass_ptrs();

  // Also checks that certain machines are slower with compressed oops
  // in vm_version initialization code.
#endif // _LP64
#endif // !ZERO
}

void Arguments::set_parallel_gc_flags() {
  assert(UseParallelGC || UseParallelOldGC, "Error");
  // Enable ParallelOld unless it was explicitly disabled (cmd line or rc file).
  if (FLAG_IS_DEFAULT(UseParallelOldGC)) {
    FLAG_SET_DEFAULT(UseParallelOldGC, true);
  }
  FLAG_SET_DEFAULT(UseParallelGC, true);

  // If no heap maximum was requested explicitly, use some reasonable fraction
  // of the physical memory, up to a maximum of 1GB.
  FLAG_SET_DEFAULT(ParallelGCThreads,
                   Abstract_VM_Version::parallel_worker_threads());
  if (ParallelGCThreads == 0) {
    jio_fprintf(defaultStream::error_stream(),
        "The Parallel GC can not be combined with -XX:ParallelGCThreads=0\n");
    vm_exit(1);
  }


  // If InitialSurvivorRatio or MinSurvivorRatio were not specified, but the
  // SurvivorRatio has been set, reset their default values to SurvivorRatio +
  // 2.  By doing this we make SurvivorRatio also work for Parallel Scavenger.
  // See CR 6362902 for details.
  if (!FLAG_IS_DEFAULT(SurvivorRatio)) {
    if (FLAG_IS_DEFAULT(InitialSurvivorRatio)) {
       FLAG_SET_DEFAULT(InitialSurvivorRatio, SurvivorRatio + 2);
    }
    if (FLAG_IS_DEFAULT(MinSurvivorRatio)) {
      FLAG_SET_DEFAULT(MinSurvivorRatio, SurvivorRatio + 2);
    }
  }

  if (UseParallelOldGC) {
    // Par compact uses lower default values since they are treated as
    // minimums.  These are different defaults because of the different
    // interpretation and are not ergonomically set.
    if (FLAG_IS_DEFAULT(MarkSweepDeadRatio)) {
      FLAG_SET_DEFAULT(MarkSweepDeadRatio, 1);
    }
  }
}

void Arguments::set_g1_gc_flags() {
  assert(UseG1GC, "Error");
#ifdef COMPILER1
  FastTLABRefill = false;
#endif
  FLAG_SET_DEFAULT(ParallelGCThreads,
                     Abstract_VM_Version::parallel_worker_threads());
  if (ParallelGCThreads == 0) {
    FLAG_SET_DEFAULT(ParallelGCThreads,
                     Abstract_VM_Version::parallel_worker_threads());
  }

  // MarkStackSize will be set (if it hasn't been set by the user)
  // when concurrent marking is initialized.
  // Its value will be based upon the number of parallel marking threads.
  // But we do set the maximum mark stack size here.
  if (FLAG_IS_DEFAULT(MarkStackSizeMax)) {
    FLAG_SET_DEFAULT(MarkStackSizeMax, 128 * TASKQUEUE_SIZE);
  }

  if (FLAG_IS_DEFAULT(GCTimeRatio) || GCTimeRatio == 0) {
    // In G1, we want the default GC overhead goal to be higher than
    // say in PS. So we set it here to 10%. Otherwise the heap might
    // be expanded more aggressively than we would like it to. In
    // fact, even 10% seems to not be high enough in some cases
    // (especially small GC stress tests that the main thing they do
    // is allocation). We might consider increase it further.
    FLAG_SET_DEFAULT(GCTimeRatio, 9);
  }

  if (PrintGCDetails && Verbose) {
    tty->print_cr("MarkStackSize: %uk  MarkStackSizeMax: %uk",
      MarkStackSize / K, MarkStackSizeMax / K);
    tty->print_cr("ConcGCThreads: %u", ConcGCThreads);
  }
}

julong Arguments::limit_by_allocatable_memory(julong limit) {
  julong max_allocatable;
  julong result = limit;
  if (os::has_allocatable_memory_limit(&max_allocatable)) {
    result = MIN2(result, max_allocatable / MaxVirtMemFraction);
  }
  return result;
}

void Arguments::set_heap_size() {
  if (!FLAG_IS_DEFAULT(DefaultMaxRAMFraction)) {
    // Deprecated flag
    FLAG_SET_CMDLINE(uintx, MaxRAMFraction, DefaultMaxRAMFraction);
  }

  const julong phys_mem =
    FLAG_IS_DEFAULT(MaxRAM) ? MIN2(os::physical_memory(), (julong)MaxRAM)
                            : (julong)MaxRAM;

  // If the maximum heap size has not been set with -Xmx,
  // then set it as fraction of the size of physical memory,
  // respecting the maximum and minimum sizes of the heap.
  if (FLAG_IS_DEFAULT(MaxHeapSize)) {
    julong reasonable_max = phys_mem / MaxRAMFraction;

    if (phys_mem <= MaxHeapSize * MinRAMFraction) {
      // Small physical memory, so use a minimum fraction of it for the heap
      reasonable_max = phys_mem / MinRAMFraction;
    } else {
      // Not-small physical memory, so require a heap at least
      // as large as MaxHeapSize
      reasonable_max = MAX2(reasonable_max, (julong)MaxHeapSize);
    }
    if (!FLAG_IS_DEFAULT(ErgoHeapSizeLimit) && ErgoHeapSizeLimit != 0) {
      // Limit the heap size to ErgoHeapSizeLimit
      reasonable_max = MIN2(reasonable_max, (julong)ErgoHeapSizeLimit);
    }
    if (UseCompressedOops) {
      // Limit the heap size to the maximum possible when using compressed oops
      julong max_coop_heap = (julong)max_heap_for_compressed_oops();
      if (HeapBaseMinAddress + MaxHeapSize < max_coop_heap) {
        // Heap should be above HeapBaseMinAddress to get zero based compressed oops
        // but it should be not less than default MaxHeapSize.
        max_coop_heap -= HeapBaseMinAddress;
      }
      reasonable_max = MIN2(reasonable_max, max_coop_heap);
    }
    reasonable_max = limit_by_allocatable_memory(reasonable_max);

    if (!FLAG_IS_DEFAULT(InitialHeapSize)) {
      // An initial heap size was specified on the command line,
      // so be sure that the maximum size is consistent.  Done
      // after call to limit_by_allocatable_memory because that
      // method might reduce the allocation size.
      reasonable_max = MAX2(reasonable_max, (julong)InitialHeapSize);
    }

    if (PrintGCDetails && Verbose) {
      // Cannot use gclog_or_tty yet.
      tty->print_cr("  Maximum heap size " SIZE_FORMAT, reasonable_max);
    }
    FLAG_SET_ERGO(uintx, MaxHeapSize, (uintx)reasonable_max);
  }

  // If the minimum or initial heap_size have not been set or requested to be set
  // ergonomically, set them accordingly.
  if (InitialHeapSize == 0 || min_heap_size() == 0) {
    julong reasonable_minimum = (julong)(OldSize + NewSize);

    reasonable_minimum = MIN2(reasonable_minimum, (julong)MaxHeapSize);

    reasonable_minimum = limit_by_allocatable_memory(reasonable_minimum);

    if (InitialHeapSize == 0) {
      julong reasonable_initial = phys_mem / InitialRAMFraction;

      reasonable_initial = MAX3(reasonable_initial, reasonable_minimum, (julong)min_heap_size());
      reasonable_initial = MIN2(reasonable_initial, (julong)MaxHeapSize);

      reasonable_initial = limit_by_allocatable_memory(reasonable_initial);

      if (PrintGCDetails && Verbose) {
        // Cannot use gclog_or_tty yet.
        tty->print_cr("  Initial heap size " SIZE_FORMAT, (uintx)reasonable_initial);
      }
      FLAG_SET_ERGO(uintx, InitialHeapSize, (uintx)reasonable_initial);
    }
    // If the minimum heap size has not been set (via -Xms),
    // synchronize with InitialHeapSize to avoid errors with the default value.
    if (min_heap_size() == 0) {
      set_min_heap_size(MIN2((uintx)reasonable_minimum, InitialHeapSize));
      if (PrintGCDetails && Verbose) {
        // Cannot use gclog_or_tty yet.
        tty->print_cr("  Minimum heap size " SIZE_FORMAT, min_heap_size());
      }
    }
  }
}

// This must be called after ergonomics because we want bytecode rewriting
// if the server compiler is used, or if UseSharedSpaces is disabled.
void Arguments::set_bytecode_flags() {
  // Better not attempt to store into a read-only space.
  if (UseSharedSpaces) {
    FLAG_SET_DEFAULT(RewriteBytecodes, false);
    FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
  }

  if (!RewriteBytecodes) {
    FLAG_SET_DEFAULT(RewriteFrequentPairs, false);
  }
}

// Aggressive optimization flags  -XX:+AggressiveOpts
void Arguments::set_aggressive_opts_flags() {
#ifdef COMPILER2
  if (AggressiveUnboxing) {
    if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
      FLAG_SET_DEFAULT(EliminateAutoBox, true);
    } else if (!EliminateAutoBox) {
      // warning("AggressiveUnboxing is disabled because EliminateAutoBox is disabled");
      AggressiveUnboxing = false;
    }
    if (FLAG_IS_DEFAULT(DoEscapeAnalysis)) {
      FLAG_SET_DEFAULT(DoEscapeAnalysis, true);
    } else if (!DoEscapeAnalysis) {
      // warning("AggressiveUnboxing is disabled because DoEscapeAnalysis is disabled");
      AggressiveUnboxing = false;
    }
  }
  if (AggressiveOpts || !FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
    if (FLAG_IS_DEFAULT(EliminateAutoBox)) {
      FLAG_SET_DEFAULT(EliminateAutoBox, true);
    }
    if (FLAG_IS_DEFAULT(AutoBoxCacheMax)) {
      FLAG_SET_DEFAULT(AutoBoxCacheMax, 20000);
    }

    // Feed the cache size setting into the JDK
    char buffer[1024];
    sprintf(buffer, "java.lang.Integer.IntegerCache.high=" INTX_FORMAT, AutoBoxCacheMax);
    add_property(buffer);
  }
  if (AggressiveOpts && FLAG_IS_DEFAULT(BiasedLockingStartupDelay)) {
    FLAG_SET_DEFAULT(BiasedLockingStartupDelay, 500);
  }
#endif

  if (AggressiveOpts) {
// Sample flag setting code
//    if (FLAG_IS_DEFAULT(EliminateZeroing)) {
//      FLAG_SET_DEFAULT(EliminateZeroing, true);
//    }
  }
}

//===========================================================================================================
// Parsing of java.compiler property

void Arguments::process_java_compiler_argument(char* arg) {
  // For backwards compatibility, Djava.compiler=NONE or ""
  // causes us to switch to -Xint mode UNLESS -Xdebug
  // is also specified.
  if (strlen(arg) == 0 || strcasecmp(arg, "NONE") == 0) {
    set_java_compiler(true);    // "-Djava.compiler[=...]" most recently seen.
  }
}

void Arguments::process_java_launcher_argument(const char* launcher, void* extra_info) {
  _sun_java_launcher = strdup(launcher);
  if (strcmp("gamma", _sun_java_launcher) == 0) {
    _created_by_gamma_launcher = true;
  }
}

bool Arguments::created_by_java_launcher() {
  assert(_sun_java_launcher != NULL, "property must have value");
  return strcmp(DEFAULT_JAVA_LAUNCHER, _sun_java_launcher) != 0;
}

bool Arguments::created_by_gamma_launcher() {
  return _created_by_gamma_launcher;
}

//===========================================================================================================
// Parsing of main arguments

bool Arguments::verify_interval(uintx val, uintx min,
                                uintx max, const char* name) {
  // Returns true iff value is in the inclusive interval [min..max]
  // false, otherwise.
  if (val >= min && val <= max) {
    return true;
  }
  jio_fprintf(defaultStream::error_stream(),
              "%s of " UINTX_FORMAT " is invalid; must be between " UINTX_FORMAT
              " and " UINTX_FORMAT "\n",
              name, val, min, max);
  return false;
}

bool Arguments::verify_min_value(intx val, intx min, const char* name) {
  // Returns true if given value is at least specified min threshold
  // false, otherwise.
  if (val >= min ) {
      return true;
  }
  jio_fprintf(defaultStream::error_stream(),
              "%s of " INTX_FORMAT " is invalid; must be at least " INTX_FORMAT "\n",
              name, val, min);
  return false;
}

bool Arguments::verify_percentage(uintx value, const char* name) {
  if (value <= 100) {
    return true;
  }
  jio_fprintf(defaultStream::error_stream(),
              "%s of " UINTX_FORMAT " is invalid; must be between 0 and 100\n",
              name, value);
  return false;
}

#if !INCLUDE_ALL_GCS
#ifdef ASSERT
static bool verify_serial_gc_flags() {
  return (UseSerialGC &&
        !(UseParNewGC || (UseConcMarkSweepGC || CMSIncrementalMode) || UseG1GC ||
          UseParallelGC || UseParallelOldGC));
}
#endif // ASSERT
#endif // INCLUDE_ALL_GCS

// check if do gclog rotation
// +UseGCLogFileRotation is a must,
// no gc log rotation when log file not supplied or
// NumberOfGCLogFiles is 0, or GCLogFileSize is 0
void check_gclog_consistency() {
  if (UseGCLogFileRotation) {
    if ((Arguments::gc_log_filename() == NULL) ||
        (NumberOfGCLogFiles == 0)  ||
        (GCLogFileSize == 0)) {
      jio_fprintf(defaultStream::output_stream(),
                  "To enable GC log rotation, use -Xloggc:<filename> -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles= -XX:GCLogFileSize=[k|K|m|M|g|G]\n"
                  "where num_of_file > 0 and num_of_size > 0\n"
                  "GC log rotation is turned off\n");
      UseGCLogFileRotation = false;
    }
  }

  if (UseGCLogFileRotation && GCLogFileSize < 8*K) {
        FLAG_SET_CMDLINE(uintx, GCLogFileSize, 8*K);
        jio_fprintf(defaultStream::output_stream(),
                    "GCLogFileSize changed to minimum 8K\n");
  }
}

// This function is called for -Xloggc:<filename>, it can be used
// to check if a given file name(or string) conforms to the following
// specification:
// A valid string only contains "[A-Z][a-z][0-9].-_%[p|t]"
// %p and %t only allowed once. We only limit usage of filename not path
bool is_filename_valid(const char *file_name) {
  const char* p = file_name;
  char file_sep = os::file_separator()[0];
  const char* cp;
  // skip prefix path
  for (cp = file_name; *cp != '\0'; cp++) {
    if (*cp == '/' || *cp == file_sep) {
      p = cp + 1;
    }
  }

  int count_p = 0;
  int count_t = 0;
  while (*p != '\0') {
    if ((*p >= '0' && *p <= '9') ||
        (*p >= 'A' && *p <= 'Z') ||
        (*p >= 'a' && *p <= 'z') ||
         *p == '-'               ||
         *p == '_'               ||
         *p == '.') {
       p++;
       continue;
    }
    if (*p == '%') {
      if(*(p + 1) == 'p') {
        p += 2;
        count_p ++;
        continue;
      }
      if (*(p + 1) == 't') {
        p += 2;
        count_t ++;
        continue;
      }
    }
    return false;
  }
  return count_p < 2 && count_t < 2;
}

// Check consistency of GC selection
bool Arguments::check_gc_consistency() {
  check_gclog_consistency();
  bool status = true;
  // Ensure that the user has not selected conflicting sets
  // of collectors. [Note: this check is merely a user convenience;
  // collectors over-ride each other so that only a non-conflicting
  // set is selected; however what the user gets is not what they
  // may have expected from the combination they asked for. It's
  // better to reduce user confusion by not allowing them to
  // select conflicting combinations.
  uint i = 0;
  if (UseSerialGC)                       i++;
  if (UseConcMarkSweepGC || UseParNewGC) i++;
  if (UseParallelGC || UseParallelOldGC) i++;
  if (UseG1GC)                           i++;
  if (i > 1) {
    jio_fprintf(defaultStream::error_stream(),
                "Conflicting collector combinations in option list; "
                "please refer to the release notes for the combinations "
                "allowed\n");
    status = false;
  }
  return status;
}

void Arguments::check_deprecated_gcs() {
  if (UseConcMarkSweepGC && !UseParNewGC) {
    warning("Using the DefNew young collector with the CMS collector is deprecated "
        "and will likely be removed in a future release");
  }

  if (UseParNewGC && !UseConcMarkSweepGC) {
    // !UseConcMarkSweepGC means that we are using serial old gc. Unfortunately we don't
    // set up UseSerialGC properly, so that can't be used in the check here.
    warning("Using the ParNew young collector with the Serial old collector is deprecated "
        "and will likely be removed in a future release");
  }

  if (CMSIncrementalMode) {
    warning("Using incremental CMS is deprecated and will likely be removed in a future release");
  }
}

void Arguments::check_deprecated_gc_flags() {
  if (FLAG_IS_CMDLINE(MaxGCMinorPauseMillis)) {
    warning("Using MaxGCMinorPauseMillis as minor pause goal is deprecated"
            "and will likely be removed in future release");
  }
  if (FLAG_IS_CMDLINE(DefaultMaxRAMFraction)) {
    warning("DefaultMaxRAMFraction is deprecated and will likely be removed in a future release. "
        "Use MaxRAMFraction instead.");
  }
  if (FLAG_IS_CMDLINE(UseCMSCompactAtFullCollection)) {
    warning("UseCMSCompactAtFullCollection is deprecated and will likely be removed in a future release.");
  }
  if (FLAG_IS_CMDLINE(CMSFullGCsBeforeCompaction)) {
    warning("CMSFullGCsBeforeCompaction is deprecated and will likely be removed in a future release.");
  }
  if (FLAG_IS_CMDLINE(UseCMSCollectionPassing)) {
    warning("UseCMSCollectionPassing is deprecated and will likely be removed in a future release.");
  }
}

// Check stack pages settings
bool Arguments::check_stack_pages()
{
  bool status = true;
  status = status && verify_min_value(StackYellowPages, 1, "StackYellowPages");
  status = status && verify_min_value(StackRedPages, 1, "StackRedPages");
  // greater stack shadow pages can't generate instruction to bang stack
  status = status && verify_interval(StackShadowPages, 1, 50, "StackShadowPages");
  return status;
}

// Check the consistency of vm_init_args
bool Arguments::check_vm_args_consistency() {
  // Method for adding checks for flag consistency.
  // The intent is to warn the user of all possible conflicts,
  // before returning an error.
  // Note: Needs platform-dependent factoring.
  bool status = true;

  // Allow both -XX:-UseStackBanging and -XX:-UseBoundThreads in non-product
  // builds so the cost of stack banging can be measured.
#if (defined(PRODUCT) && defined(SOLARIS))
  if (!UseBoundThreads && !UseStackBanging) {
    jio_fprintf(defaultStream::error_stream(),
                "-UseStackBanging conflicts with -UseBoundThreads\n");

     status = false;
  }
#endif

  if (TLABRefillWasteFraction == 0) {
    jio_fprintf(defaultStream::error_stream(),
                "TLABRefillWasteFraction should be a denominator, "
                "not " SIZE_FORMAT "\n",
                TLABRefillWasteFraction);
    status = false;
  }

  status = status && verify_interval(AdaptiveSizePolicyWeight, 0, 100,
                              "AdaptiveSizePolicyWeight");
  status = status && verify_percentage(ThresholdTolerance, "ThresholdTolerance");
  status = status && verify_percentage(MinHeapFreeRatio, "MinHeapFreeRatio");
  status = status && verify_percentage(MaxHeapFreeRatio, "MaxHeapFreeRatio");

  // Divide by bucket size to prevent a large size from causing rollover when
  // calculating amount of memory needed to be allocated for the String table.
  status = status && verify_interval(StringTableSize, minimumStringTableSize,
    (max_uintx / StringTable::bucket_size()), "StringTable size");

  status = status && verify_interval(SymbolTableSize, minimumSymbolTableSize,
    (max_uintx / SymbolTable::bucket_size()), "SymbolTable size");

  if (MinHeapFreeRatio > MaxHeapFreeRatio) {
    jio_fprintf(defaultStream::error_stream(),
                "MinHeapFreeRatio (" UINTX_FORMAT ") must be less than or "
                "equal to MaxHeapFreeRatio (" UINTX_FORMAT ")\n",
                MinHeapFreeRatio, MaxHeapFreeRatio);
    status = false;
  }
  // Keeping the heap 100% free is hard ;-) so limit it to 99%.
  MinHeapFreeRatio = MIN2(MinHeapFreeRatio, (uintx) 99);

  // Min/MaxMetaspaceFreeRatio
  status = status && verify_percentage(MinMetaspaceFreeRatio, "MinMetaspaceFreeRatio");
  status = status && verify_percentage(MaxMetaspaceFreeRatio, "MaxMetaspaceFreeRatio");

  if (MinMetaspaceFreeRatio > MaxMetaspaceFreeRatio) {
    jio_fprintf(defaultStream::error_stream(),
                "MinMetaspaceFreeRatio (%s" UINTX_FORMAT ") must be less than or "
                "equal to MaxMetaspaceFreeRatio (%s" UINTX_FORMAT ")\n",
                FLAG_IS_DEFAULT(MinMetaspaceFreeRatio) ? "Default: " : "",
                MinMetaspaceFreeRatio,
                FLAG_IS_DEFAULT(MaxMetaspaceFreeRatio) ? "Default: " : "",
                MaxMetaspaceFreeRatio);
    status = false;
  }

  // Trying to keep 100% free is not practical
  MinMetaspaceFreeRatio = MIN2(MinMetaspaceFreeRatio, (uintx) 99);

  if (FullGCALot && FLAG_IS_DEFAULT(MarkSweepAlwaysCompactCount)) {
    MarkSweepAlwaysCompactCount = 1;  // Move objects every gc.
  }

  if (UseParallelOldGC && ParallelOldGCSplitALot) {
    // Settings to encourage splitting.
    if (!FLAG_IS_CMDLINE(NewRatio)) {
      FLAG_SET_CMDLINE(uintx, NewRatio, 2);
    }
    if (!FLAG_IS_CMDLINE(ScavengeBeforeFullGC)) {
      FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
    }
  }

  status = status && verify_percentage(GCHeapFreeLimit, "GCHeapFreeLimit");
  status = status && verify_percentage(GCTimeLimit, "GCTimeLimit");
  if (GCTimeLimit == 100) {
    // Turn off gc-overhead-limit-exceeded checks
    FLAG_SET_DEFAULT(UseGCOverheadLimit, false);
  }

  status = status && check_gc_consistency();
  status = status && check_stack_pages();

  if (CMSIncrementalMode) {
    if (!UseConcMarkSweepGC) {
      jio_fprintf(defaultStream::error_stream(),
                  "error:  invalid argument combination.\n"
                  "The CMS collector (-XX:+UseConcMarkSweepGC) must be "
                  "selected in order\nto use CMSIncrementalMode.\n");
      status = false;
    } else {
      status = status && verify_percentage(CMSIncrementalDutyCycle,
                                  "CMSIncrementalDutyCycle");
      status = status && verify_percentage(CMSIncrementalDutyCycleMin,
                                  "CMSIncrementalDutyCycleMin");
      status = status && verify_percentage(CMSIncrementalSafetyFactor,
                                  "CMSIncrementalSafetyFactor");
      status = status && verify_percentage(CMSIncrementalOffset,
                                  "CMSIncrementalOffset");
      status = status && verify_percentage(CMSExpAvgFactor,
                                  "CMSExpAvgFactor");
      // If it was not set on the command line, set
      // CMSInitiatingOccupancyFraction to 1 so icms can initiate cycles early.
      if (CMSInitiatingOccupancyFraction < 0) {
        FLAG_SET_DEFAULT(CMSInitiatingOccupancyFraction, 1);
      }
    }
  }

  // CMS space iteration, which FLSVerifyAllHeapreferences entails,
  // insists that we hold the requisite locks so that the iteration is
  // MT-safe. For the verification at start-up and shut-down, we don't
  // yet have a good way of acquiring and releasing these locks,
  // which are not visible at the CollectedHeap level. We want to
  // be able to acquire these locks and then do the iteration rather
  // than just disable the lock verification. This will be fixed under
  // bug 4788986.
  if (UseConcMarkSweepGC && FLSVerifyAllHeapReferences) {
    if (VerifyDuringStartup) {
      warning("Heap verification at start-up disabled "
              "(due to current incompatibility with FLSVerifyAllHeapReferences)");
      VerifyDuringStartup = false; // Disable verification at start-up
    }

    if (VerifyBeforeExit) {
      warning("Heap verification at shutdown disabled "
              "(due to current incompatibility with FLSVerifyAllHeapReferences)");
      VerifyBeforeExit = false; // Disable verification at shutdown
    }
  }

  // Note: only executed in non-PRODUCT mode
  if (!UseAsyncConcMarkSweepGC &&
      (ExplicitGCInvokesConcurrent ||
       ExplicitGCInvokesConcurrentAndUnloadsClasses)) {
    jio_fprintf(defaultStream::error_stream(),
                "error: +ExplicitGCInvokesConcurrent[AndUnloadsClasses] conflicts"
                " with -UseAsyncConcMarkSweepGC");
    status = false;
  }

  status = status && verify_min_value(ParGCArrayScanChunk, 1, "ParGCArrayScanChunk");

#if INCLUDE_ALL_GCS
  if (UseG1GC) {
    status = status && verify_percentage(G1NewSizePercent, "G1NewSizePercent");
    status = status && verify_percentage(G1MaxNewSizePercent, "G1MaxNewSizePercent");
    status = status && verify_interval(G1NewSizePercent, 0, G1MaxNewSizePercent, "G1NewSizePercent");

    status = status && verify_percentage(InitiatingHeapOccupancyPercent,
                                         "InitiatingHeapOccupancyPercent");
    status = status && verify_min_value(G1RefProcDrainInterval, 1,
                                        "G1RefProcDrainInterval");
    status = status && verify_min_value((intx)G1ConcMarkStepDurationMillis, 1,
                                        "G1ConcMarkStepDurationMillis");
    status = status && verify_interval(G1ConcRSHotCardLimit, 0, max_jubyte,
                                       "G1ConcRSHotCardLimit");
    status = status && verify_interval(G1ConcRSLogCacheSize, 0, 31,
                                       "G1ConcRSLogCacheSize");
  }
  if (UseConcMarkSweepGC) {
    status = status && verify_min_value(CMSOldPLABNumRefills, 1, "CMSOldPLABNumRefills");
    status = status && verify_min_value(CMSOldPLABToleranceFactor, 1, "CMSOldPLABToleranceFactor");
    status = status && verify_min_value(CMSOldPLABMax, 1, "CMSOldPLABMax");
    status = status && verify_interval(CMSOldPLABMin, 1, CMSOldPLABMax, "CMSOldPLABMin");

    status = status && verify_min_value(CMSYoungGenPerWorker, 1, "CMSYoungGenPerWorker");

    status = status && verify_min_value(CMSSamplingGrain, 1, "CMSSamplingGrain");
    status = status && verify_interval(CMS_SweepWeight, 0, 100, "CMS_SweepWeight");
    status = status && verify_interval(CMS_FLSWeight, 0, 100, "CMS_FLSWeight");

    status = status && verify_interval(FLSCoalescePolicy, 0, 4, "FLSCoalescePolicy");

    status = status && verify_min_value(CMSRescanMultiple, 1, "CMSRescanMultiple");
    status = status && verify_min_value(CMSConcMarkMultiple, 1, "CMSConcMarkMultiple");

    status = status && verify_interval(CMSPrecleanIter, 0, 9, "CMSPrecleanIter");
    status = status && verify_min_value(CMSPrecleanDenominator, 1, "CMSPrecleanDenominator");
    status = status && verify_interval(CMSPrecleanNumerator, 0, CMSPrecleanDenominator - 1, "CMSPrecleanNumerator");

    status = status && verify_percentage(CMSBootstrapOccupancy, "CMSBootstrapOccupancy");

    status = status && verify_min_value(CMSPrecleanThreshold, 100, "CMSPrecleanThreshold");

    status = status && verify_percentage(CMSScheduleRemarkEdenPenetration, "CMSScheduleRemarkEdenPenetration");
    status = status && verify_min_value(CMSScheduleRemarkSamplingRatio, 1, "CMSScheduleRemarkSamplingRatio");
    status = status && verify_min_value(CMSBitMapYieldQuantum, 1, "CMSBitMapYieldQuantum");
    status = status && verify_percentage(CMSTriggerRatio, "CMSTriggerRatio");
    status = status && verify_percentage(CMSIsTooFullPercentage, "CMSIsTooFullPercentage");
  }

  if (UseParallelGC || UseParallelOldGC) {
    status = status && verify_interval(ParallelOldDeadWoodLimiterMean, 0, 100, "ParallelOldDeadWoodLimiterMean");
    status = status && verify_interval(ParallelOldDeadWoodLimiterStdDev, 0, 100, "ParallelOldDeadWoodLimiterStdDev");

    status = status && verify_percentage(YoungGenerationSizeIncrement, "YoungGenerationSizeIncrement");
    status = status && verify_percentage(TenuredGenerationSizeIncrement, "TenuredGenerationSizeIncrement");

    status = status && verify_min_value(YoungGenerationSizeSupplementDecay, 1, "YoungGenerationSizeSupplementDecay");
    status = status && verify_min_value(TenuredGenerationSizeSupplementDecay, 1, "TenuredGenerationSizeSupplementDecay");

    status = status && verify_min_value(ParGCCardsPerStrideChunk, 1, "ParGCCardsPerStrideChunk");

    status = status && verify_min_value(ParallelOldGCSplitInterval, 0, "ParallelOldGCSplitInterval");
  }
#endif // INCLUDE_ALL_GCS

  status = status && verify_interval(RefDiscoveryPolicy,
                                     ReferenceProcessor::DiscoveryPolicyMin,
                                     ReferenceProcessor::DiscoveryPolicyMax,
                                     "RefDiscoveryPolicy");

  // Limit the lower bound of this flag to 1 as it is used in a division
  // expression.
  status = status && verify_interval(TLABWasteTargetPercent,
                                     1, 100, "TLABWasteTargetPercent");

  status = status && verify_object_alignment();

  status = status && verify_interval(CompressedClassSpaceSize, 1*M, 3*G,
                                      "CompressedClassSpaceSize");

  status = status && verify_interval(MarkStackSizeMax,
                                  1, (max_jint - 1), "MarkStackSizeMax");
  status = status && verify_interval(NUMAChunkResizeWeight, 0, 100, "NUMAChunkResizeWeight");

  status = status && verify_min_value(LogEventsBufferEntries, 1, "LogEventsBufferEntries");

  status = status && verify_min_value(HeapSizePerGCThread, (uintx) os::vm_page_size(), "HeapSizePerGCThread");

  status = status && verify_min_value(GCTaskTimeStampEntries, 1, "GCTaskTimeStampEntries");

  status = status && verify_percentage(ParallelGCBufferWastePct, "ParallelGCBufferWastePct");
  status = status && verify_interval(TargetPLABWastePct, 1, 100, "TargetPLABWastePct");

  status = status && verify_min_value(ParGCStridesPerThread, 1, "ParGCStridesPerThread");

  status = status && verify_min_value(MinRAMFraction, 1, "MinRAMFraction");
  status = status && verify_min_value(InitialRAMFraction, 1, "InitialRAMFraction");
  status = status && verify_min_value(MaxRAMFraction, 1, "MaxRAMFraction");
  status = status && verify_min_value(DefaultMaxRAMFraction, 1, "DefaultMaxRAMFraction");

  status = status && verify_interval(AdaptiveTimeWeight, 0, 100, "AdaptiveTimeWeight");
  status = status && verify_min_value(AdaptiveSizeDecrementScaleFactor, 1, "AdaptiveSizeDecrementScaleFactor");

  status = status && verify_interval(TLABAllocationWeight, 0, 100, "TLABAllocationWeight");
  status = status && verify_min_value(MinTLABSize, 1, "MinTLABSize");
  status = status && verify_min_value(TLABRefillWasteFraction, 1, "TLABRefillWasteFraction");

  status = status && verify_percentage(YoungGenerationSizeSupplement, "YoungGenerationSizeSupplement");
  status = status && verify_percentage(TenuredGenerationSizeSupplement, "TenuredGenerationSizeSupplement");

  // the "age" field in the oop header is 4 bits; do not want to pull in markOop.hpp
  // just for that, so hardcode here.
  status = status && verify_interval(MaxTenuringThreshold, 0, 15, "MaxTenuringThreshold");
  status = status && verify_interval(InitialTenuringThreshold, 0, MaxTenuringThreshold, "MaxTenuringThreshold");
  status = status && verify_percentage(TargetSurvivorRatio, "TargetSurvivorRatio");
  status = status && verify_percentage(MarkSweepDeadRatio, "MarkSweepDeadRatio");

  status = status && verify_min_value(MarkSweepAlwaysCompactCount, 1, "MarkSweepAlwaysCompactCount");

  if (PrintNMTStatistics) {
#if INCLUDE_NMT
    if (MemTracker::tracking_level() == MemTracker::NMT_off) {
#endif // INCLUDE_NMT
      warning("PrintNMTStatistics is disabled, because native memory tracking is not enabled");
      PrintNMTStatistics = false;
#if INCLUDE_NMT
    }
#endif
  }

  // Need to limit the extent of the padding to reasonable size.
  // 8K is well beyond the reasonable HW cache line size, even with the
  // aggressive prefetching, while still leaving the room for segregating
  // among the distinct pages.
  if (ContendedPaddingWidth < 0 || ContendedPaddingWidth > 8192) {
    jio_fprintf(defaultStream::error_stream(),
                "ContendedPaddingWidth=" INTX_FORMAT " must be in between %d and %d\n",
                ContendedPaddingWidth, 0, 8192);
    status = false;
  }

  // Need to enforce the padding not to break the existing field alignments.
  // It is sufficient to check against the largest type size.
  if ((ContendedPaddingWidth % BytesPerLong) != 0) {
    jio_fprintf(defaultStream::error_stream(),
                "ContendedPaddingWidth=" INTX_FORMAT " must be a multiple of %d\n",
                ContendedPaddingWidth, BytesPerLong);
    status = false;
  }

  // Check lower bounds of the code cache
  // Template Interpreter code is approximately 3X larger in debug builds.
  uint min_code_cache_size = (CodeCacheMinimumUseSpace DEBUG_ONLY(* 3)) + CodeCacheMinimumFreeSpace;
  if (InitialCodeCacheSize < (uintx)os::vm_page_size()) {
    jio_fprintf(defaultStream::error_stream(),
                "Invalid InitialCodeCacheSize=%dK. Must be at least %dK.\n", InitialCodeCacheSize/K,
                os::vm_page_size()/K);
    status = false;
  } else if (ReservedCodeCacheSize < InitialCodeCacheSize) {
    jio_fprintf(defaultStream::error_stream(),
                "Invalid ReservedCodeCacheSize: %dK. Must be at least InitialCodeCacheSize=%dK.\n",
                ReservedCodeCacheSize/K, InitialCodeCacheSize/K);
    status = false;
  } else if (ReservedCodeCacheSize < min_code_cache_size) {
    jio_fprintf(defaultStream::error_stream(),
                "Invalid ReservedCodeCacheSize=%dK. Must be at least %uK.\n", ReservedCodeCacheSize/K,
                min_code_cache_size/K);
    status = false;
  } else if (ReservedCodeCacheSize > 2*G) {
    // Code cache size larger than MAXINT is not supported.
    jio_fprintf(defaultStream::error_stream(),
                "Invalid ReservedCodeCacheSize=%dM. Must be at most %uM.\n", ReservedCodeCacheSize/M,
                (2*G)/M);
    status = false;
  }

  status &= verify_interval(NmethodSweepFraction, 1, ReservedCodeCacheSize/K, "NmethodSweepFraction");
  status &= verify_interval(NmethodSweepActivity, 0, 2000, "NmethodSweepActivity");

  return status;
}

bool Arguments::is_bad_option(const JavaVMOption* option, jboolean ignore,
  const char* option_type) {
  if (ignore) return false;

  const char* spacer = " ";
  if (option_type == NULL) {
    option_type = ++spacer; // Set both to the empty string.
  }

  if (os::obsolete_option(option)) {
    jio_fprintf(defaultStream::error_stream(),
                "Obsolete %s%soption: %s\n", option_type, spacer,
      option->optionString);
    return false;
  } else {
    jio_fprintf(defaultStream::error_stream(),
                "Unrecognized %s%soption: %s\n", option_type, spacer,
      option->optionString);
    return true;
  }
}

static const char* user_assertion_options[] = {
  "-da", "-ea", "-disableassertions", "-enableassertions", 0
};

static const char* system_assertion_options[] = {
  "-dsa", "-esa", "-disablesystemassertions", "-enablesystemassertions", 0
};

// Return true if any of the strings in null-terminated array 'names' matches.
// If tail_allowed is true, then the tail must begin with a colon; otherwise,
// the option must match exactly.
static bool match_option(const JavaVMOption* option, const char** names, const char** tail,
  bool tail_allowed) {
  for (/* empty */; *names != NULL; ++names) {
    if (match_option(option, *names, tail)) {
      if (**tail == '\0' || tail_allowed && **tail == ':') {
        return true;
      }
    }
  }
  return false;
}

bool Arguments::parse_uintx(const char* value,
                            uintx* uintx_arg,
                            uintx min_size) {

  // Check the sign first since atomull() parses only unsigned values.
  bool value_is_positive = !(*value == '-');

  if (value_is_positive) {
    julong n;
    bool good_return = atomull(value, &n);
    if (good_return) {
      bool above_minimum = n >= min_size;
      bool value_is_too_large = n > max_uintx;

      if (above_minimum && !value_is_too_large) {
        *uintx_arg = n;
        return true;
      }
    }
  }
  return false;
}

Arguments::ArgsRange Arguments::parse_memory_size(const char* s,
                                                  julong* long_arg,
                                                  julong min_size) {
  if (!atomull(s, long_arg)) return arg_unreadable;
  return check_memory_size(*long_arg, min_size);
}

// Parse JavaVMInitArgs structure

jint Arguments::parse_vm_init_args(const JavaVMInitArgs* args) {
  // For components of the system classpath.
  SysClassPath scp(Arguments::get_sysclasspath());
  bool scp_assembly_required = false;

  // Save default settings for some mode flags
  Arguments::_AlwaysCompileLoopMethods = AlwaysCompileLoopMethods;
  Arguments::_UseOnStackReplacement    = UseOnStackReplacement;
  Arguments::_ClipInlining             = ClipInlining;
  Arguments::_BackgroundCompilation    = BackgroundCompilation;

  // Setup flags for mixed which is the default
  set_mode_flags(_mixed);

  // Parse JAVA_TOOL_OPTIONS environment variable (if present)
  jint result = parse_java_tool_options_environment_variable(&scp, &scp_assembly_required);
  if (result != JNI_OK) {
    return result;
  }

  // Parse JavaVMInitArgs structure passed in
  result = parse_each_vm_init_arg(args, &scp, &scp_assembly_required, Flag::COMMAND_LINE);
  if (result != JNI_OK) {
    return result;
  }

  // Parse _JAVA_OPTIONS environment variable (if present) (mimics classic VM)
  result = parse_java_options_environment_variable(&scp, &scp_assembly_required);
  if (result != JNI_OK) {
    return result;
  }

  // Do final processing now that all arguments have been parsed
  result = finalize_vm_init_args(&scp, scp_assembly_required);
  if (result != JNI_OK) {
    return result;
  }

  return JNI_OK;
}

// Checks if name in command-line argument -agent{lib,path}:name[=options]
// represents a valid HPROF of JDWP agent.  is_path==true denotes that we
// are dealing with -agentpath (case where name is a path), otherwise with
// -agentlib
bool valid_hprof_or_jdwp_agent(char *name, bool is_path) {
  char *_name;
  const char *_hprof = "hprof", *_jdwp = "jdwp";
  size_t _len_hprof, _len_jdwp, _len_prefix;

  if (is_path) {
    if ((_name = strrchr(name, (int) *os::file_separator())) == NULL) {
      return false;
    }

    _name++;  // skip past last path separator
    _len_prefix = strlen(JNI_LIB_PREFIX);

    if (strncmp(_name, JNI_LIB_PREFIX, _len_prefix) != 0) {
      return false;
    }

    _name += _len_prefix;
    _len_hprof = strlen(_hprof);
    _len_jdwp = strlen(_jdwp);

    if (strncmp(_name, _hprof, _len_hprof) == 0) {
      _name += _len_hprof;
    }
    else if (strncmp(_name, _jdwp, _len_jdwp) == 0) {
      _name += _len_jdwp;
    }
    else {
      return false;
    }

    if (strcmp(_name, JNI_LIB_SUFFIX) != 0) {
      return false;
    }

    return true;
  }

  if (strcmp(name, _hprof) == 0 || strcmp(name, _jdwp) == 0) {
    return true;
  }

  return false;
}

jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args,
                                       SysClassPath* scp_p,
                                       bool* scp_assembly_required_p,
                                       Flag::Flags origin) {
  // Remaining part of option string
  const char* tail;

  // iterate over arguments
  for (int index = 0; index < args->nOptions; index++) {
    bool is_absolute_path = false;  // for -agentpath vs -agentlib

    const JavaVMOption* option = args->options + index;

    if (!match_option(option, "-Djava.class.path", &tail) &&
        !match_option(option, "-Dsun.java.command", &tail) &&
        !match_option(option, "-Dsun.java.launcher", &tail)) {

        // add all jvm options to the jvm_args string. This string
        // is used later to set the java.vm.args PerfData string constant.
        // the -Djava.class.path and the -Dsun.java.command options are
        // omitted from jvm_args string as each have their own PerfData
        // string constant object.
        build_jvm_args(option->optionString);
    }

    // -verbose:[class/gc/jni]
    if (match_option(option, "-verbose", &tail)) {
      if (!strcmp(tail, ":class") || !strcmp(tail, "")) {
        FLAG_SET_CMDLINE(bool, TraceClassLoading, true);
        FLAG_SET_CMDLINE(bool, TraceClassUnloading, true);
      } else if (!strcmp(tail, ":gc")) {
        FLAG_SET_CMDLINE(bool, PrintGC, true);
      } else if (!strcmp(tail, ":jni")) {
        FLAG_SET_CMDLINE(bool, PrintJNIResolving, true);
      }
    // -da / -ea / -disableassertions / -enableassertions
    // These accept an optional class/package name separated by a colon, e.g.,
    // -da:java.lang.Thread.
    } else if (match_option(option, user_assertion_options, &tail, true)) {
      bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
      if (*tail == '\0') {
        JavaAssertions::setUserClassDefault(enable);
      } else {
        assert(*tail == ':', "bogus match by match_option()");
        JavaAssertions::addOption(tail + 1, enable);
      }
    // -dsa / -esa / -disablesystemassertions / -enablesystemassertions
    } else if (match_option(option, system_assertion_options, &tail, false)) {
      bool enable = option->optionString[1] == 'e';     // char after '-' is 'e'
      JavaAssertions::setSystemClassDefault(enable);
    // -bootclasspath:
    } else if (match_option(option, "-Xbootclasspath:", &tail)) {
      scp_p->reset_path(tail);
      *scp_assembly_required_p = true;
    // -bootclasspath/a:
    } else if (match_option(option, "-Xbootclasspath/a:", &tail)) {
      scp_p->add_suffix(tail);
      *scp_assembly_required_p = true;
    // -bootclasspath/p:
    } else if (match_option(option, "-Xbootclasspath/p:", &tail)) {
      scp_p->add_prefix(tail);
      *scp_assembly_required_p = true;
    // -Xrun
    } else if (match_option(option, "-Xrun", &tail)) {
      if (tail != NULL) {
        const char* pos = strchr(tail, ':');
        size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
        char* name = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len + 1, mtInternal), tail, len);
        name[len] = '\0';

        char *options = NULL;
        if(pos != NULL) {
          size_t len2 = strlen(pos+1) + 1; // options start after ':'.  Final zero must be copied.
          options = (char*)memcpy(NEW_C_HEAP_ARRAY(char, len2, mtInternal), pos+1, len2);
        }
#if !INCLUDE_JVMTI
        if ((strcmp(name, "hprof") == 0) || (strcmp(name, "jdwp") == 0)) {
          jio_fprintf(defaultStream::error_stream(),
            "Profiling and debugging agents are not supported in this VM\n");
          return JNI_ERR;
        }
#endif // !INCLUDE_JVMTI
        add_init_library(name, options);
      }
    // -agentlib and -agentpath
    } else if (match_option(option, "-agentlib:", &tail) ||
          (is_absolute_path = match_option(option, "-agentpath:", &tail))) {
      if(tail != NULL) {
        const char* pos = strchr(tail, '=');
        size_t len = (pos == NULL) ? strlen(tail) : pos - tail;
        char* name = strncpy(NEW_C_HEAP_ARRAY(char, len + 1, mtInternal), tail, len);
        name[len] = '\0';

        char *options = NULL;
        if(pos != NULL) {
          options = strcpy(NEW_C_HEAP_ARRAY(char, strlen(pos + 1) + 1, mtInternal), pos + 1);
        }
#if !INCLUDE_JVMTI
        if (valid_hprof_or_jdwp_agent(name, is_absolute_path)) {
          jio_fprintf(defaultStream::error_stream(),
            "Profiling and debugging agents are not supported in this VM\n");
          return JNI_ERR;
        }
#endif // !INCLUDE_JVMTI
        add_init_agent(name, options, is_absolute_path);
      }
    // -javaagent
    } else if (match_option(option, "-javaagent:", &tail)) {
#if !INCLUDE_JVMTI
      jio_fprintf(defaultStream::error_stream(),
        "Instrumentation agents are not supported in this VM\n");
      return JNI_ERR;
#else
      if(tail != NULL) {
        char *options = strcpy(NEW_C_HEAP_ARRAY(char, strlen(tail) + 1, mtInternal), tail);
        add_init_agent("instrument", options, false);
      }
#endif // !INCLUDE_JVMTI
    // -Xnoclassgc
    } else if (match_option(option, "-Xnoclassgc", &tail)) {
      FLAG_SET_CMDLINE(bool, ClassUnloading, false);
    // -Xincgc: i-CMS
    } else if (match_option(option, "-Xincgc", &tail)) {
      FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, true);
      FLAG_SET_CMDLINE(bool, CMSIncrementalMode, true);
    // -Xnoincgc: no i-CMS
    } else if (match_option(option, "-Xnoincgc", &tail)) {
      FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, false);
      FLAG_SET_CMDLINE(bool, CMSIncrementalMode, false);
    // -Xconcgc
    } else if (match_option(option, "-Xconcgc", &tail)) {
      FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, true);
    // -Xnoconcgc
    } else if (match_option(option, "-Xnoconcgc", &tail)) {
      FLAG_SET_CMDLINE(bool, UseConcMarkSweepGC, false);
    // -Xbatch
    } else if (match_option(option, "-Xbatch", &tail)) {
      FLAG_SET_CMDLINE(bool, BackgroundCompilation, false);
    // -Xmn for compatibility with other JVM vendors
    } else if (match_option(option, "-Xmn", &tail)) {
      julong long_initial_young_size = 0;
      ArgsRange errcode = parse_memory_size(tail, &long_initial_young_size, 1);
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid initial young generation size: %s\n", option->optionString);
        describe_range_error(errcode);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(uintx, MaxNewSize, (uintx)long_initial_young_size);
      FLAG_SET_CMDLINE(uintx, NewSize, (uintx)long_initial_young_size);
    // -Xms
    } else if (match_option(option, "-Xms", &tail)) {
      julong long_initial_heap_size = 0;
      // an initial heap size of 0 means automatically determine
      ArgsRange errcode = parse_memory_size(tail, &long_initial_heap_size, 0);
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid initial heap size: %s\n", option->optionString);
        describe_range_error(errcode);
        return JNI_EINVAL;
      }
      set_min_heap_size((uintx)long_initial_heap_size);
      // Currently the minimum size and the initial heap sizes are the same.
      // Can be overridden with -XX:InitialHeapSize.
      FLAG_SET_CMDLINE(uintx, InitialHeapSize, (uintx)long_initial_heap_size);
    // -Xmx
    } else if (match_option(option, "-Xmx", &tail) || match_option(option, "-XX:MaxHeapSize=", &tail)) {
      julong long_max_heap_size = 0;
      ArgsRange errcode = parse_memory_size(tail, &long_max_heap_size, 1);
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid maximum heap size: %s\n", option->optionString);
        describe_range_error(errcode);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(uintx, MaxHeapSize, (uintx)long_max_heap_size);
    // Xmaxf
    } else if (match_option(option, "-Xmaxf", &tail)) {
      char* err;
      int maxf = (int)(strtod(tail, &err) * 100);
      if (*err != '\0' || maxf < 0 || maxf > 100) {
        jio_fprintf(defaultStream::error_stream(),
                    "Bad max heap free percentage size: %s\n",
                    option->optionString);
        return JNI_EINVAL;
      } else {
        FLAG_SET_CMDLINE(uintx, MaxHeapFreeRatio, maxf);
      }
    // Xminf
    } else if (match_option(option, "-Xminf", &tail)) {
      char* err;
      int minf = (int)(strtod(tail, &err) * 100);
      if (*err != '\0' || minf < 0 || minf > 100) {
        jio_fprintf(defaultStream::error_stream(),
                    "Bad min heap free percentage size: %s\n",
                    option->optionString);
        return JNI_EINVAL;
      } else {
        FLAG_SET_CMDLINE(uintx, MinHeapFreeRatio, minf);
      }
    // -Xss
    } else if (match_option(option, "-Xss", &tail)) {
      julong long_ThreadStackSize = 0;
      ArgsRange errcode = parse_memory_size(tail, &long_ThreadStackSize, 1000);
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid thread stack size: %s\n", option->optionString);
        describe_range_error(errcode);
        return JNI_EINVAL;
      }
      // Internally track ThreadStackSize in units of 1024 bytes.
      FLAG_SET_CMDLINE(intx, ThreadStackSize,
                              round_to((int)long_ThreadStackSize, K) / K);
    // -Xoss
    } else if (match_option(option, "-Xoss", &tail)) {
          // HotSpot does not have separate native and Java stacks, ignore silently for compatibility
    } else if (match_option(option, "-XX:CodeCacheExpansionSize=", &tail)) {
      julong long_CodeCacheExpansionSize = 0;
      ArgsRange errcode = parse_memory_size(tail, &long_CodeCacheExpansionSize, os::vm_page_size());
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                   "Invalid argument: %s. Must be at least %luK.\n", option->optionString,
                   os::vm_page_size()/K);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(uintx, CodeCacheExpansionSize, (uintx)long_CodeCacheExpansionSize);
    } else if (match_option(option, "-Xmaxjitcodesize", &tail) ||
               match_option(option, "-XX:ReservedCodeCacheSize=", &tail)) {
      julong long_ReservedCodeCacheSize = 0;

      ArgsRange errcode = parse_memory_size(tail, &long_ReservedCodeCacheSize, 1);
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid maximum code cache size: %s.\n", option->optionString);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(uintx, ReservedCodeCacheSize, (uintx)long_ReservedCodeCacheSize);
      //-XX:IncreaseFirstTierCompileThresholdAt=
      } else if (match_option(option, "-XX:IncreaseFirstTierCompileThresholdAt=", &tail)) {
        uintx uint_IncreaseFirstTierCompileThresholdAt = 0;
        if (!parse_uintx(tail, &uint_IncreaseFirstTierCompileThresholdAt, 0) || uint_IncreaseFirstTierCompileThresholdAt > 99) {
          jio_fprintf(defaultStream::error_stream(),
                      "Invalid value for IncreaseFirstTierCompileThresholdAt: %s. Should be between 0 and 99.\n",
                      option->optionString);
          return JNI_EINVAL;
        }
        FLAG_SET_CMDLINE(uintx, IncreaseFirstTierCompileThresholdAt, (uintx)uint_IncreaseFirstTierCompileThresholdAt);
    // -green
    } else if (match_option(option, "-green", &tail)) {
      jio_fprintf(defaultStream::error_stream(),
                  "Green threads support not available\n");
          return JNI_EINVAL;
    // -native
    } else if (match_option(option, "-native", &tail)) {
          // HotSpot always uses native threads, ignore silently for compatibility
    // -Xsqnopause
    } else if (match_option(option, "-Xsqnopause", &tail)) {
          // EVM option, ignore silently for compatibility
    // -Xrs
    } else if (match_option(option, "-Xrs", &tail)) {
          // Classic/EVM option, new functionality
      FLAG_SET_CMDLINE(bool, ReduceSignalUsage, true);
    } else if (match_option(option, "-Xusealtsigs", &tail)) {
          // change default internal VM signals used - lower case for back compat
      FLAG_SET_CMDLINE(bool, UseAltSigs, true);
    // -Xoptimize
    } else if (match_option(option, "-Xoptimize", &tail)) {
          // EVM option, ignore silently for compatibility
    // -Xprof
    } else if (match_option(option, "-Xprof", &tail)) {
#if INCLUDE_FPROF
      _has_profile = true;
#else // INCLUDE_FPROF
      jio_fprintf(defaultStream::error_stream(),
        "Flat profiling is not supported in this VM.\n");
      return JNI_ERR;
#endif // INCLUDE_FPROF
    // -Xconcurrentio
    } else if (match_option(option, "-Xconcurrentio", &tail)) {
      FLAG_SET_CMDLINE(bool, UseLWPSynchronization, true);
      FLAG_SET_CMDLINE(bool, BackgroundCompilation, false);
      FLAG_SET_CMDLINE(intx, DeferThrSuspendLoopCount, 1);
      FLAG_SET_CMDLINE(bool, UseTLAB, false);
      FLAG_SET_CMDLINE(uintx, NewSizeThreadIncrease, 16 * K);  // 20Kb per thread added to new generation

      // -Xinternalversion
    } else if (match_option(option, "-Xinternalversion", &tail)) {
      jio_fprintf(defaultStream::output_stream(), "%s\n",
                  VM_Version::internal_vm_info_string());
      vm_exit(0);
#ifndef PRODUCT
    // -Xprintflags
    } else if (match_option(option, "-Xprintflags", &tail)) {
      CommandLineFlags::printFlags(tty, false);
      vm_exit(0);
#endif
    // -D
    } else if (match_option(option, "-D", &tail)) {
      if (!add_property(tail)) {
        return JNI_ENOMEM;
      }
      // Out of the box management support
      if (match_option(option, "-Dcom.sun.management", &tail)) {
#if INCLUDE_MANAGEMENT
        FLAG_SET_CMDLINE(bool, ManagementServer, true);
#else
        jio_fprintf(defaultStream::output_stream(),
          "-Dcom.sun.management is not supported in this VM.\n");
        return JNI_ERR;
#endif
      }
    // -Xint
    } else if (match_option(option, "-Xint", &tail)) {
          set_mode_flags(_int);
    // -Xmixed
    } else if (match_option(option, "-Xmixed", &tail)) {
          set_mode_flags(_mixed);
    // -Xcomp
    } else if (match_option(option, "-Xcomp", &tail)) {
      // for testing the compiler; turn off all flags that inhibit compilation
          set_mode_flags(_comp);
    // -Xshare:dump
    } else if (match_option(option, "-Xshare:dump", &tail)) {
      FLAG_SET_CMDLINE(bool, DumpSharedSpaces, true);
      set_mode_flags(_int);     // Prevent compilation, which creates objects
    // -Xshare:on
    } else if (match_option(option, "-Xshare:on", &tail)) {
      FLAG_SET_CMDLINE(bool, UseSharedSpaces, true);
      FLAG_SET_CMDLINE(bool, RequireSharedSpaces, true);
    // -Xshare:auto
    } else if (match_option(option, "-Xshare:auto", &tail)) {
      FLAG_SET_CMDLINE(bool, UseSharedSpaces, true);
      FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false);
    // -Xshare:off
    } else if (match_option(option, "-Xshare:off", &tail)) {
      FLAG_SET_CMDLINE(bool, UseSharedSpaces, false);
      FLAG_SET_CMDLINE(bool, RequireSharedSpaces, false);
    // -Xverify
    } else if (match_option(option, "-Xverify", &tail)) {
      if (strcmp(tail, ":all") == 0 || strcmp(tail, "") == 0) {
        FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, true);
        FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true);
      } else if (strcmp(tail, ":remote") == 0) {
        FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false);
        FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, true);
      } else if (strcmp(tail, ":none") == 0) {
        FLAG_SET_CMDLINE(bool, BytecodeVerificationLocal, false);
        FLAG_SET_CMDLINE(bool, BytecodeVerificationRemote, false);
      } else if (is_bad_option(option, args->ignoreUnrecognized, "verification")) {
        return JNI_EINVAL;
      }
    // -Xdebug
    } else if (match_option(option, "-Xdebug", &tail)) {
      // note this flag has been used, then ignore
      set_xdebug_mode(true);
    // -Xnoagent
    } else if (match_option(option, "-Xnoagent", &tail)) {
      // For compatibility with classic. HotSpot refuses to load the old style agent.dll.
    } else if (match_option(option, "-Xboundthreads", &tail)) {
      // Bind user level threads to kernel threads (Solaris only)
      FLAG_SET_CMDLINE(bool, UseBoundThreads, true);
    } else if (match_option(option, "-Xloggc:", &tail)) {
      // Redirect GC output to the file. -Xloggc:<filename>
      // ostream_init_log(), when called will use this filename
      // to initialize a fileStream.
      _gc_log_filename = strdup(tail);
     if (!is_filename_valid(_gc_log_filename)) {
       jio_fprintf(defaultStream::output_stream(),
                  "Invalid file name for use with -Xloggc: Filename can only contain the "
                  "characters [A-Z][a-z][0-9]-_.%%[p|t] but it has been %s\n"
                  "Note %%p or %%t can only be used once\n", _gc_log_filename);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(bool, PrintGC, true);
      FLAG_SET_CMDLINE(bool, PrintGCTimeStamps, true);

    // JNI hooks
    } else if (match_option(option, "-Xcheck", &tail)) {
      if (!strcmp(tail, ":jni")) {
#if !INCLUDE_JNI_CHECK
        warning("JNI CHECKING is not supported in this VM");
#else
        CheckJNICalls = true;
#endif // INCLUDE_JNI_CHECK
      } else if (is_bad_option(option, args->ignoreUnrecognized,
                                     "check")) {
        return JNI_EINVAL;
      }
    } else if (match_option(option, "vfprintf", &tail)) {
      _vfprintf_hook = CAST_TO_FN_PTR(vfprintf_hook_t, option->extraInfo);
    } else if (match_option(option, "exit", &tail)) {
      _exit_hook = CAST_TO_FN_PTR(exit_hook_t, option->extraInfo);
    } else if (match_option(option, "abort", &tail)) {
      _abort_hook = CAST_TO_FN_PTR(abort_hook_t, option->extraInfo);
    // -XX:+AggressiveHeap
    } else if (match_option(option, "-XX:+AggressiveHeap", &tail)) {

      // This option inspects the machine and attempts to set various
      // parameters to be optimal for long-running, memory allocation
      // intensive jobs.  It is intended for machines with large
      // amounts of cpu and memory.

      // initHeapSize is needed since _initial_heap_size is 4 bytes on a 32 bit
      // VM, but we may not be able to represent the total physical memory
      // available (like having 8gb of memory on a box but using a 32bit VM).
      // Thus, we need to make sure we're using a julong for intermediate
      // calculations.
      julong initHeapSize;
      julong total_memory = os::physical_memory();

      if (total_memory < (julong)256*M) {
        jio_fprintf(defaultStream::error_stream(),
                    "You need at least 256mb of memory to use -XX:+AggressiveHeap\n");
        vm_exit(1);
      }

      // The heap size is half of available memory, or (at most)
      // all of possible memory less 160mb (leaving room for the OS
      // when using ISM).  This is the maximum; because adaptive sizing
      // is turned on below, the actual space used may be smaller.

      initHeapSize = MIN2(total_memory / (julong)2,
                          total_memory - (julong)160*M);

      initHeapSize = limit_by_allocatable_memory(initHeapSize);

      if (FLAG_IS_DEFAULT(MaxHeapSize)) {
         FLAG_SET_CMDLINE(uintx, MaxHeapSize, initHeapSize);
         FLAG_SET_CMDLINE(uintx, InitialHeapSize, initHeapSize);
         // Currently the minimum size and the initial heap sizes are the same.
         set_min_heap_size(initHeapSize);
      }
      if (FLAG_IS_DEFAULT(NewSize)) {
         // Make the young generation 3/8ths of the total heap.
         FLAG_SET_CMDLINE(uintx, NewSize,
                                ((julong)MaxHeapSize / (julong)8) * (julong)3);
         FLAG_SET_CMDLINE(uintx, MaxNewSize, NewSize);
      }

#ifndef _ALLBSD_SOURCE  // UseLargePages is not yet supported on BSD.
      FLAG_SET_DEFAULT(UseLargePages, true);
#endif

      // Increase some data structure sizes for efficiency
      FLAG_SET_CMDLINE(uintx, BaseFootPrintEstimate, MaxHeapSize);
      FLAG_SET_CMDLINE(bool, ResizeTLAB, false);
      FLAG_SET_CMDLINE(uintx, TLABSize, 256*K);

      // See the OldPLABSize comment below, but replace 'after promotion'
      // with 'after copying'.  YoungPLABSize is the size of the survivor
      // space per-gc-thread buffers.  The default is 4kw.
      FLAG_SET_CMDLINE(uintx, YoungPLABSize, 256*K);      // Note: this is in words

      // OldPLABSize is the size of the buffers in the old gen that
      // UseParallelGC uses to promote live data that doesn't fit in the
      // survivor spaces.  At any given time, there's one for each gc thread.
      // The default size is 1kw. These buffers are rarely used, since the
      // survivor spaces are usually big enough.  For specjbb, however, there
      // are occasions when there's lots of live data in the young gen
      // and we end up promoting some of it.  We don't have a definite
      // explanation for why bumping OldPLABSize helps, but the theory
      // is that a bigger PLAB results in retaining something like the
      // original allocation order after promotion, which improves mutator
      // locality.  A minor effect may be that larger PLABs reduce the
      // number of PLAB allocation events during gc.  The value of 8kw
      // was arrived at by experimenting with specjbb.
      FLAG_SET_CMDLINE(uintx, OldPLABSize, 8*K);  // Note: this is in words

      // Enable parallel GC and adaptive generation sizing
      FLAG_SET_CMDLINE(bool, UseParallelGC, true);
      FLAG_SET_DEFAULT(ParallelGCThreads,
                       Abstract_VM_Version::parallel_worker_threads());

      // Encourage steady state memory management
      FLAG_SET_CMDLINE(uintx, ThresholdTolerance, 100);

      // This appears to improve mutator locality
      FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);

      // Get around early Solaris scheduling bug
      // (affinity vs other jobs on system)
      // but disallow DR and offlining (5008695).
      FLAG_SET_CMDLINE(bool, BindGCTaskThreadsToCPUs, true);

    } else if (match_option(option, "-XX:+NeverTenure", &tail)) {
      // The last option must always win.
      FLAG_SET_CMDLINE(bool, AlwaysTenure, false);
      FLAG_SET_CMDLINE(bool, NeverTenure, true);
    } else if (match_option(option, "-XX:+AlwaysTenure", &tail)) {
      // The last option must always win.
      FLAG_SET_CMDLINE(bool, NeverTenure, false);
      FLAG_SET_CMDLINE(bool, AlwaysTenure, true);
    } else if (match_option(option, "-XX:+CMSPermGenSweepingEnabled", &tail) ||
               match_option(option, "-XX:-CMSPermGenSweepingEnabled", &tail)) {
      jio_fprintf(defaultStream::error_stream(),
        "Please use CMSClassUnloadingEnabled in place of "
        "CMSPermGenSweepingEnabled in the future\n");
    } else if (match_option(option, "-XX:+UseGCTimeLimit", &tail)) {
      FLAG_SET_CMDLINE(bool, UseGCOverheadLimit, true);
      jio_fprintf(defaultStream::error_stream(),
        "Please use -XX:+UseGCOverheadLimit in place of "
        "-XX:+UseGCTimeLimit in the future\n");
    } else if (match_option(option, "-XX:-UseGCTimeLimit", &tail)) {
      FLAG_SET_CMDLINE(bool, UseGCOverheadLimit, false);
      jio_fprintf(defaultStream::error_stream(),
        "Please use -XX:-UseGCOverheadLimit in place of "
        "-XX:-UseGCTimeLimit in the future\n");
    // The TLE options are for compatibility with 1.3 and will be
    // removed without notice in a future release.  These options
    // are not to be documented.
    } else if (match_option(option, "-XX:MaxTLERatio=", &tail)) {
      // No longer used.
    } else if (match_option(option, "-XX:+ResizeTLE", &tail)) {
      FLAG_SET_CMDLINE(bool, ResizeTLAB, true);
    } else if (match_option(option, "-XX:-ResizeTLE", &tail)) {
      FLAG_SET_CMDLINE(bool, ResizeTLAB, false);
    } else if (match_option(option, "-XX:+PrintTLE", &tail)) {
      FLAG_SET_CMDLINE(bool, PrintTLAB, true);
    } else if (match_option(option, "-XX:-PrintTLE", &tail)) {
      FLAG_SET_CMDLINE(bool, PrintTLAB, false);
    } else if (match_option(option, "-XX:TLEFragmentationRatio=", &tail)) {
      // No longer used.
    } else if (match_option(option, "-XX:TLESize=", &tail)) {
      julong long_tlab_size = 0;
      ArgsRange errcode = parse_memory_size(tail, &long_tlab_size, 1);
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid TLAB size: %s\n", option->optionString);
        describe_range_error(errcode);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(uintx, TLABSize, long_tlab_size);
    } else if (match_option(option, "-XX:TLEThreadRatio=", &tail)) {
      // No longer used.
    } else if (match_option(option, "-XX:+UseTLE", &tail)) {
      FLAG_SET_CMDLINE(bool, UseTLAB, true);
    } else if (match_option(option, "-XX:-UseTLE", &tail)) {
      FLAG_SET_CMDLINE(bool, UseTLAB, false);
    } else if (match_option(option, "-XX:+DisplayVMOutputToStderr", &tail)) {
      FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, false);
      FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, true);
    } else if (match_option(option, "-XX:+DisplayVMOutputToStdout", &tail)) {
      FLAG_SET_CMDLINE(bool, DisplayVMOutputToStderr, false);
      FLAG_SET_CMDLINE(bool, DisplayVMOutputToStdout, true);
    } else if (match_option(option, "-XX:+ExtendedDTraceProbes", &tail)) {
#if defined(DTRACE_ENABLED)
      FLAG_SET_CMDLINE(bool, ExtendedDTraceProbes, true);
      FLAG_SET_CMDLINE(bool, DTraceMethodProbes, true);
      FLAG_SET_CMDLINE(bool, DTraceAllocProbes, true);
      FLAG_SET_CMDLINE(bool, DTraceMonitorProbes, true);
#else // defined(DTRACE_ENABLED)
      jio_fprintf(defaultStream::error_stream(),
                  "ExtendedDTraceProbes flag is not applicable for this configuration\n");
      return JNI_EINVAL;
#endif // defined(DTRACE_ENABLED)
#ifdef ASSERT
    } else if (match_option(option, "-XX:+FullGCALot", &tail)) {
      FLAG_SET_CMDLINE(bool, FullGCALot, true);
      // disable scavenge before parallel mark-compact
      FLAG_SET_CMDLINE(bool, ScavengeBeforeFullGC, false);
#endif
    } else if (match_option(option, "-XX:CMSParPromoteBlocksToClaim=", &tail)) {
      julong cms_blocks_to_claim = (julong)atol(tail);
      FLAG_SET_CMDLINE(uintx, CMSParPromoteBlocksToClaim, cms_blocks_to_claim);
      jio_fprintf(defaultStream::error_stream(),
        "Please use -XX:OldPLABSize in place of "
        "-XX:CMSParPromoteBlocksToClaim in the future\n");
    } else if (match_option(option, "-XX:ParCMSPromoteBlocksToClaim=", &tail)) {
      julong cms_blocks_to_claim = (julong)atol(tail);
      FLAG_SET_CMDLINE(uintx, CMSParPromoteBlocksToClaim, cms_blocks_to_claim);
      jio_fprintf(defaultStream::error_stream(),
        "Please use -XX:OldPLABSize in place of "
        "-XX:ParCMSPromoteBlocksToClaim in the future\n");
    } else if (match_option(option, "-XX:ParallelGCOldGenAllocBufferSize=", &tail)) {
      julong old_plab_size = 0;
      ArgsRange errcode = parse_memory_size(tail, &old_plab_size, 1);
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid old PLAB size: %s\n", option->optionString);
        describe_range_error(errcode);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(uintx, OldPLABSize, old_plab_size);
      jio_fprintf(defaultStream::error_stream(),
                  "Please use -XX:OldPLABSize in place of "
                  "-XX:ParallelGCOldGenAllocBufferSize in the future\n");
    } else if (match_option(option, "-XX:ParallelGCToSpaceAllocBufferSize=", &tail)) {
      julong young_plab_size = 0;
      ArgsRange errcode = parse_memory_size(tail, &young_plab_size, 1);
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid young PLAB size: %s\n", option->optionString);
        describe_range_error(errcode);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(uintx, YoungPLABSize, young_plab_size);
      jio_fprintf(defaultStream::error_stream(),
                  "Please use -XX:YoungPLABSize in place of "
                  "-XX:ParallelGCToSpaceAllocBufferSize in the future\n");
    } else if (match_option(option, "-XX:CMSMarkStackSize=", &tail) ||
               match_option(option, "-XX:G1MarkStackSize=", &tail)) {
      julong stack_size = 0;
      ArgsRange errcode = parse_memory_size(tail, &stack_size, 1);
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid mark stack size: %s\n", option->optionString);
        describe_range_error(errcode);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(uintx, MarkStackSize, stack_size);
    } else if (match_option(option, "-XX:CMSMarkStackSizeMax=", &tail)) {
      julong max_stack_size = 0;
      ArgsRange errcode = parse_memory_size(tail, &max_stack_size, 1);
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid maximum mark stack size: %s\n",
                    option->optionString);
        describe_range_error(errcode);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(uintx, MarkStackSizeMax, max_stack_size);
    } else if (match_option(option, "-XX:ParallelMarkingThreads=", &tail) ||
               match_option(option, "-XX:ParallelCMSThreads=", &tail)) {
      uintx conc_threads = 0;
      if (!parse_uintx(tail, &conc_threads, 1)) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid concurrent threads: %s\n", option->optionString);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(uintx, ConcGCThreads, conc_threads);
    } else if (match_option(option, "-XX:MaxDirectMemorySize=", &tail)) {
      julong max_direct_memory_size = 0;
      ArgsRange errcode = parse_memory_size(tail, &max_direct_memory_size, 0);
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid maximum direct memory size: %s\n",
                    option->optionString);
        describe_range_error(errcode);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(uintx, MaxDirectMemorySize, max_direct_memory_size);
    } else if (match_option(option, "-XX:+UseVMInterruptibleIO", &tail)) {
      // NOTE! In JDK 9, the UseVMInterruptibleIO flag will completely go
      //       away and will cause VM initialization failures!
      warning("-XX:+UseVMInterruptibleIO is obsolete and will be removed in a future release.");
      FLAG_SET_CMDLINE(bool, UseVMInterruptibleIO, true);
#if !INCLUDE_MANAGEMENT
    } else if (match_option(option, "-XX:+ManagementServer", &tail)) {
        jio_fprintf(defaultStream::error_stream(),
          "ManagementServer is not supported in this VM.\n");
        return JNI_ERR;
#endif // INCLUDE_MANAGEMENT
    } else if (match_option(option, "-XX:", &tail)) { // -XX:xxxx
      // Skip -XX:Flags= since that case has already been handled
      if (strncmp(tail, "Flags=", strlen("Flags=")) != 0) {
        if (!process_argument(tail, args->ignoreUnrecognized, origin)) {
          return JNI_EINVAL;
        }
      }
    // Unknown option
    } else if (is_bad_option(option, args->ignoreUnrecognized)) {
      return JNI_ERR;
    }
  }

  // Change the default value for flags  which have different default values
  // when working with older JDKs.
#ifdef LINUX
 if (JDK_Version::current().compare_major(6) <= 0 &&
      FLAG_IS_DEFAULT(UseLinuxPosixThreadCPUClocks)) {
    FLAG_SET_DEFAULT(UseLinuxPosixThreadCPUClocks, false);
  }
#endif // LINUX
  return JNI_OK;
}

jint Arguments::finalize_vm_init_args(SysClassPath* scp_p, bool scp_assembly_required) {
  // This must be done after all -D arguments have been processed.
  scp_p->expand_endorsed();

  if (scp_assembly_required || scp_p->get_endorsed() != NULL) {
    // Assemble the bootclasspath elements into the final path.
    Arguments::set_sysclasspath(scp_p->combined_path());
  }

  // This must be done after all arguments have been processed.
  // java_compiler() true means set to "NONE" or empty.
  if (java_compiler() && !xdebug_mode()) {
    // For backwards compatibility, we switch to interpreted mode if
    // -Djava.compiler="NONE" or "" is specified AND "-Xdebug" was
    // not specified.
    set_mode_flags(_int);
  }
  if (CompileThreshold == 0) {
    set_mode_flags(_int);
  }

  // eventually fix up InitialTenuringThreshold if only MaxTenuringThreshold is set
  if (FLAG_IS_DEFAULT(InitialTenuringThreshold) && (InitialTenuringThreshold > MaxTenuringThreshold)) {
    FLAG_SET_ERGO(uintx, InitialTenuringThreshold, MaxTenuringThreshold);
  }

#ifndef COMPILER2
  // Don't degrade server performance for footprint
  if (FLAG_IS_DEFAULT(UseLargePages) &&
      MaxHeapSize < LargePageHeapSizeThreshold) {
    // No need for large granularity pages w/small heaps.
    // Note that large pages are enabled/disabled for both the
    // Java heap and the code cache.
    FLAG_SET_DEFAULT(UseLargePages, false);
  }

#else
  if (!FLAG_IS_DEFAULT(OptoLoopAlignment) && FLAG_IS_DEFAULT(MaxLoopPad)) {
    FLAG_SET_DEFAULT(MaxLoopPad, OptoLoopAlignment-1);
  }
#endif

#ifndef TIERED
  // Tiered compilation is undefined.
  UNSUPPORTED_OPTION(TieredCompilation, "TieredCompilation");
#endif

  // If we are running in a headless jre, force java.awt.headless property
  // to be true unless the property has already been set.
  // Also allow the OS environment variable JAVA_AWT_HEADLESS to set headless state.
  if (os::is_headless_jre()) {
    const char* headless = Arguments::get_property("java.awt.headless");
    if (headless == NULL) {
      char envbuffer[128];
      if (!os::getenv("JAVA_AWT_HEADLESS", envbuffer, sizeof(envbuffer))) {
        if (!add_property("java.awt.headless=true")) {
          return JNI_ENOMEM;
        }
      } else {
        char buffer[256];
        strcpy(buffer, "java.awt.headless=");
        strcat(buffer, envbuffer);
        if (!add_property(buffer)) {
          return JNI_ENOMEM;
        }
      }
    }
  }

  if (!check_vm_args_consistency()) {
    return JNI_ERR;
  }

  return JNI_OK;
}

jint Arguments::parse_java_options_environment_variable(SysClassPath* scp_p, bool* scp_assembly_required_p) {
  return parse_options_environment_variable("_JAVA_OPTIONS", scp_p,
                                            scp_assembly_required_p);
}

jint Arguments::parse_java_tool_options_environment_variable(SysClassPath* scp_p, bool* scp_assembly_required_p) {
  return parse_options_environment_variable("JAVA_TOOL_OPTIONS", scp_p,
                                            scp_assembly_required_p);
}

jint Arguments::parse_options_environment_variable(const char* name, SysClassPath* scp_p, bool* scp_assembly_required_p) {
  const int N_MAX_OPTIONS = 64;
  const int OPTION_BUFFER_SIZE = 1024;
  char buffer[OPTION_BUFFER_SIZE];

  // The variable will be ignored if it exceeds the length of the buffer.
  // Don't check this variable if user has special privileges
  // (e.g. unix su command).
  if (os::getenv(name, buffer, sizeof(buffer)) &&
      !os::have_special_privileges()) {
    JavaVMOption options[N_MAX_OPTIONS];      // Construct option array
    jio_fprintf(defaultStream::error_stream(),
                "Picked up %s: %s\n", name, buffer);
    char* rd = buffer;                        // pointer to the input string (rd)
    int i;
    for (i = 0; i < N_MAX_OPTIONS;) {         // repeat for all options in the input string
      while (isspace(*rd)) rd++;              // skip whitespace
      if (*rd == 0) break;                    // we re done when the input string is read completely

      // The output, option string, overwrites the input string.
      // Because of quoting, the pointer to the option string (wrt) may lag the pointer to
      // input string (rd).
      char* wrt = rd;

      options[i++].optionString = wrt;        // Fill in option
      while (*rd != 0 && !isspace(*rd)) {     // unquoted strings terminate with a space or NULL
        if (*rd == '\'' || *rd == '"') {      // handle a quoted string
          int quote = *rd;                    // matching quote to look for
          rd++;                               // don't copy open quote
          while (*rd != quote) {              // include everything (even spaces) up until quote
            if (*rd == 0) {                   // string termination means unmatched string
              jio_fprintf(defaultStream::error_stream(),
                          "Unmatched quote in %s\n", name);
              return JNI_ERR;
            }
            *wrt++ = *rd++;                   // copy to option string
          }
          rd++;                               // don't copy close quote
        } else {
          *wrt++ = *rd++;                     // copy to option string
        }
      }
      // Need to check if we're done before writing a NULL,
      // because the write could be to the byte that rd is pointing to.
      if (*rd++ == 0) {
        *wrt = 0;
        break;
      }
      *wrt = 0;                               // Zero terminate option
    }
    // Construct JavaVMInitArgs structure and parse as if it was part of the command line
    JavaVMInitArgs vm_args;
    vm_args.version = JNI_VERSION_1_2;
    vm_args.options = options;
    vm_args.nOptions = i;
    vm_args.ignoreUnrecognized = IgnoreUnrecognizedVMOptions;

    if (PrintVMOptions) {
      const char* tail;
      for (int i = 0; i < vm_args.nOptions; i++) {
        const JavaVMOption *option = vm_args.options + i;
        if (match_option(option, "-XX:", &tail)) {
          logOption(tail);
        }
      }
    }

    return(parse_each_vm_init_arg(&vm_args, scp_p, scp_assembly_required_p, Flag::ENVIRON_VAR));
  }
  return JNI_OK;
}

void Arguments::set_shared_spaces_flags() {
  if (DumpSharedSpaces) {
    if (RequireSharedSpaces) {
      warning("cannot dump shared archive while using shared archive");
    }
    UseSharedSpaces = false;
#ifdef _LP64
    if (!UseCompressedOops || !UseCompressedClassPointers) {
      vm_exit_during_initialization(
        "Cannot dump shared archive when UseCompressedOops or UseCompressedClassPointers is off.", NULL);
    }
  } else {
    // UseCompressedOops and UseCompressedClassPointers must be on for UseSharedSpaces.
    if (!UseCompressedOops || !UseCompressedClassPointers) {
      no_shared_spaces();
    }
#endif
  }
}

#if !INCLUDE_ALL_GCS
static void force_serial_gc() {
  FLAG_SET_DEFAULT(UseSerialGC, true);
  FLAG_SET_DEFAULT(CMSIncrementalMode, false);  // special CMS suboption
  UNSUPPORTED_GC_OPTION(UseG1GC);
  UNSUPPORTED_GC_OPTION(UseParallelGC);
  UNSUPPORTED_GC_OPTION(UseParallelOldGC);
  UNSUPPORTED_GC_OPTION(UseConcMarkSweepGC);
  UNSUPPORTED_GC_OPTION(UseParNewGC);
}
#endif // INCLUDE_ALL_GCS

// Sharing support
// Construct the path to the archive
static char* get_shared_archive_path() {
  char *shared_archive_path;
  if (SharedArchiveFile == NULL) {
    char jvm_path[JVM_MAXPATHLEN];
    os::jvm_path(jvm_path, sizeof(jvm_path));
    char *end = strrchr(jvm_path, *os::file_separator());
    if (end != NULL) *end = '\0';
    size_t jvm_path_len = strlen(jvm_path);
    size_t file_sep_len = strlen(os::file_separator());
    shared_archive_path = NEW_C_HEAP_ARRAY(char, jvm_path_len +
        file_sep_len + 20, mtInternal);
    if (shared_archive_path != NULL) {
      strncpy(shared_archive_path, jvm_path, jvm_path_len + 1);
      strncat(shared_archive_path, os::file_separator(), file_sep_len);
      strncat(shared_archive_path, "classes.jsa", 11);
    }
  } else {
    shared_archive_path = NEW_C_HEAP_ARRAY(char, strlen(SharedArchiveFile) + 1, mtInternal);
    if (shared_archive_path != NULL) {
      strncpy(shared_archive_path, SharedArchiveFile, strlen(SharedArchiveFile) + 1);
    }
  }
  return shared_archive_path;
}

#ifndef PRODUCT
// Determine whether LogVMOutput should be implicitly turned on.
static bool use_vm_log() {
  if (LogCompilation || !FLAG_IS_DEFAULT(LogFile) ||
      PrintCompilation || PrintInlining || PrintDependencies || PrintNativeNMethods ||
      PrintDebugInfo || PrintRelocations || PrintNMethods || PrintExceptionHandlers ||
      PrintAssembly || TraceDeoptimization || TraceDependencies ||
      (VerifyDependencies && FLAG_IS_CMDLINE(VerifyDependencies))) {
    return true;
  }

#ifdef COMPILER1
  if (PrintC1Statistics) {
    return true;
  }
#endif // COMPILER1

#ifdef COMPILER2
  if (PrintOptoAssembly || PrintOptoStatistics) {
    return true;
  }
#endif // COMPILER2

  return false;
}
#endif // PRODUCT

// Parse entry point called from JNI_CreateJavaVM

jint Arguments::parse(const JavaVMInitArgs* args) {

  // Remaining part of option string
  const char* tail;

  // If flag "-XX:Flags=flags-file" is used it will be the first option to be processed.
  const char* hotspotrc = ".hotspotrc";
  bool settings_file_specified = false;
  bool needs_hotspotrc_warning = false;

  const char* flags_file;
  int index;
  for (index = 0; index < args->nOptions; index++) {
    const JavaVMOption *option = args->options + index;
    if (match_option(option, "-XX:Flags=", &tail)) {
      flags_file = tail;
      settings_file_specified = true;
    }
    if (match_option(option, "-XX:+PrintVMOptions", &tail)) {
      PrintVMOptions = true;
    }
    if (match_option(option, "-XX:-PrintVMOptions", &tail)) {
      PrintVMOptions = false;
    }
    if (match_option(option, "-XX:+IgnoreUnrecognizedVMOptions", &tail)) {
      IgnoreUnrecognizedVMOptions = true;
    }
    if (match_option(option, "-XX:-IgnoreUnrecognizedVMOptions", &tail)) {
      IgnoreUnrecognizedVMOptions = false;
    }
    if (match_option(option, "-XX:+PrintFlagsInitial", &tail)) {
      CommandLineFlags::printFlags(tty, false);
      vm_exit(0);
    }
    if (match_option(option, "-XX:NativeMemoryTracking", &tail)) {
#if INCLUDE_NMT
      MemTracker::init_tracking_options(tail);
#else
      jio_fprintf(defaultStream::error_stream(),
        "Native Memory Tracking is not supported in this VM\n");
      return JNI_ERR;
#endif
    }


#ifndef PRODUCT
    if (match_option(option, "-XX:+PrintFlagsWithComments", &tail)) {
      CommandLineFlags::printFlags(tty, true);
      vm_exit(0);
    }
#endif
  }

  if (IgnoreUnrecognizedVMOptions) {
    // uncast const to modify the flag args->ignoreUnrecognized
    *(jboolean*)(&args->ignoreUnrecognized) = true;
  }

  // Parse specified settings file
  if (settings_file_specified) {
    if (!process_settings_file(flags_file, true, args->ignoreUnrecognized)) {
      return JNI_EINVAL;
    }
  } else {
#ifdef ASSERT
    // Parse default .hotspotrc settings file
    if (!process_settings_file(".hotspotrc", false, args->ignoreUnrecognized)) {
      return JNI_EINVAL;
    }
#else
    struct stat buf;
    if (os::stat(hotspotrc, &buf) == 0) {
      needs_hotspotrc_warning = true;
    }
#endif
  }

  if (PrintVMOptions) {
    for (index = 0; index < args->nOptions; index++) {
      const JavaVMOption *option = args->options + index;
      if (match_option(option, "-XX:", &tail)) {
        logOption(tail);
      }
    }
  }

  // Parse JavaVMInitArgs structure passed in, as well as JAVA_TOOL_OPTIONS and _JAVA_OPTIONS
  jint result = parse_vm_init_args(args);
  if (result != JNI_OK) {
    return result;
  }

  // Call get_shared_archive_path() here, after possible SharedArchiveFile option got parsed.
  SharedArchivePath = get_shared_archive_path();
  if (SharedArchivePath == NULL) {
    return JNI_ENOMEM;
  }

  // Delay warning until here so that we've had a chance to process
  // the -XX:-PrintWarnings flag
  if (needs_hotspotrc_warning) {
    warning("%s file is present but has been ignored.  "
            "Run with -XX:Flags=%s to load the file.",
            hotspotrc, hotspotrc);
  }

#ifdef _ALLBSD_SOURCE  // UseLargePages is not yet supported on BSD.
  UNSUPPORTED_OPTION(UseLargePages, "-XX:+UseLargePages");
#endif

#if INCLUDE_ALL_GCS
  #if (defined JAVASE_EMBEDDED || defined ARM)
    UNSUPPORTED_OPTION(UseG1GC, "G1 GC");
  #endif
#endif

#ifndef PRODUCT
  if (TraceBytecodesAt != 0) {
    TraceBytecodes = true;
  }
  if (CountCompiledCalls) {
    if (UseCounterDecay) {
      warning("UseCounterDecay disabled because CountCalls is set");
      UseCounterDecay = false;
    }
  }
#endif // PRODUCT

  // JSR 292 is not supported before 1.7
  if (!JDK_Version::is_gte_jdk17x_version()) {
    if (EnableInvokeDynamic) {
      if (!FLAG_IS_DEFAULT(EnableInvokeDynamic)) {
        warning("JSR 292 is not supported before 1.7.  Disabling support.");
      }
      EnableInvokeDynamic = false;
    }
  }

  if (EnableInvokeDynamic && ScavengeRootsInCode == 0) {
    if (!FLAG_IS_DEFAULT(ScavengeRootsInCode)) {
      warning("forcing ScavengeRootsInCode non-zero because EnableInvokeDynamic is true");
    }
    ScavengeRootsInCode = 1;
  }

  if (PrintGCDetails) {
    // Turn on -verbose:gc options as well
    PrintGC = true;
  }

  if (!JDK_Version::is_gte_jdk18x_version()) {
    // To avoid changing the log format for 7 updates this flag is only
    // true by default in JDK8 and above.
    if (FLAG_IS_DEFAULT(PrintGCCause)) {
      FLAG_SET_DEFAULT(PrintGCCause, false);
    }
  }

  // Set object alignment values.
  set_object_alignment();

#if !INCLUDE_ALL_GCS
  force_serial_gc();
#endif // INCLUDE_ALL_GCS
#if !INCLUDE_CDS
  if (DumpSharedSpaces || RequireSharedSpaces) {
    jio_fprintf(defaultStream::error_stream(),
      "Shared spaces are not supported in this VM\n");
    return JNI_ERR;
  }
  if ((UseSharedSpaces && FLAG_IS_CMDLINE(UseSharedSpaces)) || PrintSharedSpaces) {
    warning("Shared spaces are not supported in this VM");
    FLAG_SET_DEFAULT(UseSharedSpaces, false);
    FLAG_SET_DEFAULT(PrintSharedSpaces, false);
  }
  no_shared_spaces();
#endif // INCLUDE_CDS

  return JNI_OK;
}

jint Arguments::apply_ergo() {

  // Set flags based on ergonomics.
  set_ergonomics_flags();

  set_shared_spaces_flags();

  // Check the GC selections again.
  if (!check_gc_consistency()) {
    return JNI_EINVAL;
  }

  if (TieredCompilation) {
    set_tiered_flags();
  } else {
    // Check if the policy is valid. Policies 0 and 1 are valid for non-tiered setup.
    if (CompilationPolicyChoice >= 2) {
      vm_exit_during_initialization(
        "Incompatible compilation policy selected", NULL);
    }
  }
  // Set NmethodSweepFraction after the size of the code cache is adapted (in case of tiered)
  if (FLAG_IS_DEFAULT(NmethodSweepFraction)) {
    FLAG_SET_DEFAULT(NmethodSweepFraction, 1 + ReservedCodeCacheSize / (16 * M));
  }


  // Set heap size based on available physical memory
  set_heap_size();

#if INCLUDE_ALL_GCS
  // Set per-collector flags
  if (UseParallelGC || UseParallelOldGC) {
    set_parallel_gc_flags();
  } else if (UseConcMarkSweepGC) { // should be done before ParNew check below
    set_cms_and_parnew_gc_flags();
  } else if (UseParNewGC) {  // skipped if CMS is set above
    set_parnew_gc_flags();
  } else if (UseG1GC) {
    set_g1_gc_flags();
  }
  check_deprecated_gcs();
  check_deprecated_gc_flags();
  if (AssumeMP && !UseSerialGC) {
    if (FLAG_IS_DEFAULT(ParallelGCThreads) && ParallelGCThreads == 1) {
      warning("If the number of processors is expected to increase from one, then"
              " you should configure the number of parallel GC threads appropriately"
              " using -XX:ParallelGCThreads=N");
    }
  }
#else // INCLUDE_ALL_GCS
  assert(verify_serial_gc_flags(), "SerialGC unset");
#endif // INCLUDE_ALL_GCS

  // Initialize Metaspace flags and alignments.
  Metaspace::ergo_initialize();

  // Set bytecode rewriting flags
  set_bytecode_flags();

  // Set flags if Aggressive optimization flags (-XX:+AggressiveOpts) enabled.
  set_aggressive_opts_flags();

  // Turn off biased locking for locking debug mode flags,
  // which are subtlely different from each other but neither works with
  // biased locking.
  if (UseHeavyMonitors
#ifdef COMPILER1
      || !UseFastLocking
#endif // COMPILER1
    ) {
    if (!FLAG_IS_DEFAULT(UseBiasedLocking) && UseBiasedLocking) {
      // flag set to true on command line; warn the user that they
      // can't enable biased locking here
      warning("Biased Locking is not supported with locking debug flags"
              "; ignoring UseBiasedLocking flag." );
    }
    UseBiasedLocking = false;
  }

#ifdef CC_INTERP
  // Clear flags not supported by the C++ interpreter
  FLAG_SET_DEFAULT(ProfileInterpreter, false);
  FLAG_SET_DEFAULT(UseBiasedLocking, false);
  LP64_ONLY(FLAG_SET_DEFAULT(UseCompressedOops, false));
  LP64_ONLY(FLAG_SET_DEFAULT(UseCompressedClassPointers, false));
#endif // CC_INTERP

#ifdef COMPILER2
  if (!UseBiasedLocking || EmitSync != 0) {
    UseOptoBiasInlining = false;
  }
  if (!EliminateLocks) {
    EliminateNestedLocks = false;
  }
  if (!Inline) {
    IncrementalInline = false;
  }
#ifndef PRODUCT
  if (!IncrementalInline) {
    AlwaysIncrementalInline = false;
  }
#endif
  if (IncrementalInline && FLAG_IS_DEFAULT(MaxNodeLimit)) {
    // incremental inlining: bump MaxNodeLimit
    FLAG_SET_DEFAULT(MaxNodeLimit, (intx)75000);
  }
  if (!UseTypeSpeculation && FLAG_IS_DEFAULT(TypeProfileLevel)) {
    // nothing to use the profiling, turn if off
    FLAG_SET_DEFAULT(TypeProfileLevel, 0);
  }
  if (UseTypeSpeculation && FLAG_IS_DEFAULT(ReplaceInParentMaps)) {
    // Doing the replace in parent maps helps speculation
    FLAG_SET_DEFAULT(ReplaceInParentMaps, true);
  }
#ifndef X86
  // Only on x86 for now
  FLAG_SET_DEFAULT(TypeProfileLevel, 0);
#endif
#endif

  if (PrintAssembly && FLAG_IS_DEFAULT(DebugNonSafepoints)) {
    warning("PrintAssembly is enabled; turning on DebugNonSafepoints to gain additional output");
    DebugNonSafepoints = true;
  }

  if (FLAG_IS_CMDLINE(CompressedClassSpaceSize) && !UseCompressedClassPointers) {
    warning("Setting CompressedClassSpaceSize has no effect when compressed class pointers are not used");
  }

#ifndef PRODUCT
  if (CompileTheWorld) {
    // Force NmethodSweeper to sweep whole CodeCache each time.
    if (FLAG_IS_DEFAULT(NmethodSweepFraction)) {
      NmethodSweepFraction = 1;
    }
  }

  if (!LogVMOutput && FLAG_IS_DEFAULT(LogVMOutput)) {
    if (use_vm_log()) {
      LogVMOutput = true;
    }
  }
#endif // PRODUCT

  if (PrintCommandLineFlags) {
    CommandLineFlags::printSetFlags(tty);
  }

  // Apply CPU specific policy for the BiasedLocking
  if (UseBiasedLocking) {
    if (!VM_Version::use_biased_locking() &&
        !(FLAG_IS_CMDLINE(UseBiasedLocking))) {
      UseBiasedLocking = false;
    }
  }

  // set PauseAtExit if the gamma launcher was used and a debugger is attached
  // but only if not already set on the commandline
  if (Arguments::created_by_gamma_launcher() && os::is_debugger_attached()) {
    bool set = false;
    CommandLineFlags::wasSetOnCmdline("PauseAtExit", &set);
    if (!set) {
      FLAG_SET_DEFAULT(PauseAtExit, true);
    }
  }

  return JNI_OK;
}

jint Arguments::adjust_after_os() {
#if INCLUDE_ALL_GCS
  if (UseParallelGC || UseParallelOldGC) {
    if (UseNUMA) {
      if (FLAG_IS_DEFAULT(MinHeapDeltaBytes)) {
        FLAG_SET_DEFAULT(MinHeapDeltaBytes, 64*M);
      }
      // For those collectors or operating systems (eg, Windows) that do
      // not support full UseNUMA, we will map to UseNUMAInterleaving for now
      UseNUMAInterleaving = true;
    }
  }
#endif // INCLUDE_ALL_GCS
  return JNI_OK;
}

int Arguments::PropertyList_count(SystemProperty* pl) {
  int count = 0;
  while(pl != NULL) {
    count++;
    pl = pl->next();
  }
  return count;
}

const char* Arguments::PropertyList_get_value(SystemProperty *pl, const char* key) {
  assert(key != NULL, "just checking");
  SystemProperty* prop;
  for (prop = pl; prop != NULL; prop = prop->next()) {
    if (strcmp(key, prop->key()) == 0) return prop->value();
  }
  return NULL;
}

const char* Arguments::PropertyList_get_key_at(SystemProperty *pl, int index) {
  int count = 0;
  const char* ret_val = NULL;

  while(pl != NULL) {
    if(count >= index) {
      ret_val = pl->key();
      break;
    }
    count++;
    pl = pl->next();
  }

  return ret_val;
}

char* Arguments::PropertyList_get_value_at(SystemProperty* pl, int index) {
  int count = 0;
  char* ret_val = NULL;

  while(pl != NULL) {
    if(count >= index) {
      ret_val = pl->value();
      break;
    }
    count++;
    pl = pl->next();
  }

  return ret_val;
}

void Arguments::PropertyList_add(SystemProperty** plist, SystemProperty *new_p) {
  SystemProperty* p = *plist;
  if (p == NULL) {
    *plist = new_p;
  } else {
    while (p->next() != NULL) {
      p = p->next();
    }
    p->set_next(new_p);
  }
}

void Arguments::PropertyList_add(SystemProperty** plist, const char* k, char* v) {
  if (plist == NULL)
    return;

  SystemProperty* new_p = new SystemProperty(k, v, true);
  PropertyList_add(plist, new_p);
}

// This add maintains unique property key in the list.
void Arguments::PropertyList_unique_add(SystemProperty** plist, const char* k, char* v, jboolean append) {
  if (plist == NULL)
    return;

  // If property key exist then update with new value.
  SystemProperty* prop;
  for (prop = *plist; prop != NULL; prop = prop->next()) {
    if (strcmp(k, prop->key()) == 0) {
      if (append) {
        prop->append_value(v);
      } else {
        prop->set_value(v);
      }
      return;
    }
  }

  PropertyList_add(plist, k, v);
}

// Copies src into buf, replacing "%%" with "%" and "%p" with pid
// Returns true if all of the source pointed by src has been copied over to
// the destination buffer pointed by buf. Otherwise, returns false.
// Notes:
// 1. If the length (buflen) of the destination buffer excluding the
// NULL terminator character is not long enough for holding the expanded
// pid characters, it also returns false instead of returning the partially
// expanded one.
// 2. The passed in "buflen" should be large enough to hold the null terminator.
bool Arguments::copy_expand_pid(const char* src, size_t srclen,
                                char* buf, size_t buflen) {
  const char* p = src;
  char* b = buf;
  const char* src_end = &src[srclen];
  char* buf_end = &buf[buflen - 1];

  while (p < src_end && b < buf_end) {
    if (*p == '%') {
      switch (*(++p)) {
      case '%':         // "%%" ==> "%"
        *b++ = *p++;
        break;
      case 'p':  {       //  "%p" ==> current process id
        // buf_end points to the character before the last character so
        // that we could write '\0' to the end of the buffer.
        size_t buf_sz = buf_end - b + 1;
        int ret = jio_snprintf(b, buf_sz, "%d", os::current_process_id());

        // if jio_snprintf fails or the buffer is not long enough to hold
        // the expanded pid, returns false.
        if (ret < 0 || ret >= (int)buf_sz) {
          return false;
        } else {
          b += ret;
          assert(*b == '\0', "fail in copy_expand_pid");
          if (p == src_end && b == buf_end + 1) {
            // reach the end of the buffer.
            return true;
          }
        }
        p++;
        break;
      }
      default :
        *b++ = '%';
      }
    } else {
      *b++ = *p++;
    }
  }
  *b = '\0';
  return (p == src_end); // return false if not all of the source was copied
}

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