view src/share/vm/runtime/arguments.cpp @ 2223:dde920245681

6896099: Integrate CMS heap ergo with default heap sizing ergo 6627787: CMS: JVM refuses to start up with -Xms16m -Xmx16m 7000125: CMS: Anti-monotone young gen sizing with respect to maximum whole heap size specification 7027529: CMS: retire CMSUseOldDefaults flag Summary: Simplify CMS heap sizing code, relying on ergonomic initial sizing consistent with other collectors for the most part, controlling only young gen sizing to rein in pause times. Make CMS young gen sizing default statically cpu-dependant. Remove inconsistencies wrt generation sizing and policy code, allowing for the fixing for 6627787 and 7000125. For 7027529, retire the flag CMSUseOldDefaults which had been introduced as a bridge from JDK 5 to JDK 6 a number of years ago. Reviewed-by: brutisso, poonam
author ysr
date Wed, 16 Mar 2011 10:37:08 -0700
parents 1fb790245268
children 048f98400b8e
line wrap: on
line source
/*
 * Copyright (c) 1997, 2011, 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 "compiler/compilerOracle.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/cardTableRS.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 "utilities/defaultStream.hpp"
#include "utilities/taskqueue.hpp"
#ifdef TARGET_ARCH_x86
# include "vm_version_x86.hpp"
#endif
#ifdef TARGET_ARCH_sparc
# include "vm_version_sparc.hpp"
#endif
#ifdef TARGET_ARCH_zero
# include "vm_version_zero.hpp"
#endif
#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
#ifndef SERIALGC
#include "gc_implementation/concurrentMarkSweep/compactibleFreeListSpace.hpp"
#endif

#define DEFAULT_VENDOR_URL_BUG "http://java.sun.com/webapps/bugreport/crash.jsp"
#define DEFAULT_JAVA_LAUNCHER  "generic"

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;
bool   Arguments::_has_alloc_profile            = false;
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;

static bool force_client_mode = false;

// 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) },
  { 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]);
    _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);
      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);
      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);
  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);
    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);
      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);
    } else {
      cp = REALLOC_C_HEAP_ARRAY(char, path, len);
      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));
  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));
      sprintf(jarpath, "%s%s%s", directory, dir_sep, name);
      path = add_to_path(path, jarpath, false);
      FREE_C_HEAP_ARRAY(char, jarpath);
    }
  }
  FREE_C_HEAP_ARRAY(char, dbuf);
  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, os::julong_format_specifier(), &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, FlagValueOrigin origin) {
  return CommandLineFlags::boolAtPut(name, &value, origin);
}

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

static bool append_to_string_flag(char* name, const char* new_value, FlagValueOrigin 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);
    // 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);
  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);
  }
  return true;
}

bool Arguments::parse_argument(const char* arg, FlagValueOrigin 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 index = *count;

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

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>");
  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, FlagValueOrigin origin) {

  JDK_Version since = JDK_Version();

  if (parse_argument(arg, origin)) {
    // do nothing
  } else if (is_newly_obsolete(arg, &since)) {
    enum { bufsize = 256 };
    char buffer[bufsize];
    since.to_string(buffer, bufsize);
    jio_fprintf(defaultStream::error_stream(),
      "Warning: The flag %s has been EOL'd as of %s and will"
      " be ignored\n", arg, buffer);
  } else {
    if (!ignore_unrecognized) {
      jio_fprintf(defaultStream::error_stream(),
                  "Unrecognized VM option '%s'\n", arg);
      // allow for commandline "commenting out" options like -XX:#+Verbose
      if (strlen(arg) == 0 || arg[0] != '#') {
        return false;
      }
    }
  }
  return true;
}

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) {
    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, 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, 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, "add_property");
  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, "add_property");
    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*)Abstract_VM_Version::vm_info_string(), false);

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

  // 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;
    break;
  }
}

// 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);
  }
}

void Arguments::set_tiered_flags() {
  if (FLAG_IS_DEFAULT(CompilationPolicyChoice)) {
    FLAG_SET_DEFAULT(CompilationPolicyChoice, 2);
  }
  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 * 2);
  }
}

#ifndef KERNEL
// If the user has chosen ParallelGCThreads > 0, we set UseParNewGC
// if it's not explictly set or unset. If the user has chosen
// UseParNewGC and not explicitly set ParallelGCThreads we
// set it, unless this is a single cpu machine.
void Arguments::set_parnew_gc_flags() {
  assert(!UseSerialGC && !UseParallelOldGC && !UseParallelGC && !UseG1GC,
         "control point invariant");
  assert(UseParNewGC, "Error");

  // Turn off AdaptiveSizePolicy by default for parnew until it is
  // complete.
  if (FLAG_IS_DEFAULT(UseAdaptiveSizePolicy)) {
    FLAG_SET_DEFAULT(UseAdaptiveSizePolicy, false);
  }

  if (ParallelGCThreads == 0) {
    FLAG_SET_DEFAULT(ParallelGCThreads,
                     Abstract_VM_Version::parallel_worker_threads());
    if (ParallelGCThreads == 1) {
      FLAG_SET_DEFAULT(UseParNewGC, false);
      FLAG_SET_DEFAULT(ParallelGCThreads, 0);
    }
  }
  if (UseParNewGC) {
    // CDS doesn't work with ParNew yet
    no_shared_spaces();

    // 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(intx, 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.
  if (FLAG_IS_DEFAULT(UseAdaptiveSizePolicy)) {
    FLAG_SET_DEFAULT(UseAdaptiveSizePolicy, false);
  }

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

  // MaxHeapSize is aligned down in collectorPolicy
  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

    assert(max_heap >= InitialHeapSize, "Error");
    assert(max_heap >= NewSize, "Error");

    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(intx, 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(intx, SurvivorRatio, MAX2((intx)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 // KERNEL

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;

#ifndef KERNEL
  // Set CMS global values
  CompactibleFreeListSpace::set_cms_values();
#endif // KERNEL
}

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 then 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 then page size %d\n",
                (int)ObjectAlignmentInBytes, os::vm_page_size());
    return false;
  }
  return true;
}

inline uintx max_heap_for_compressed_oops() {
  // Avoid sign flip.
  if (OopEncodingHeapMax < MaxPermSize + os::vm_page_size()) {
    return 0;
  }
  LP64_ONLY(return OopEncodingHeapMax - MaxPermSize - os::vm_page_size());
  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_ergonomics_flags() {
  // Parallel GC is not compatible with sharing. If one specifies
  // that they want sharing explicitly, do not set ergonomics flags.
  if (DumpSharedSpaces || RequireSharedSpaces) {
    return;
  }

  if (os::is_server_class_machine() && !force_client_mode ) {
    // 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 &&
        !DumpSharedSpaces &&
        FLAG_IS_DEFAULT(UseParallelGC)) {
      if (should_auto_select_low_pause_collector()) {
        FLAG_SET_ERGO(bool, UseConcMarkSweepGC, true);
      } else {
        FLAG_SET_ERGO(bool, UseParallelGC, true);
      }
      no_shared_spaces();
    }
  }

#ifndef ZERO
#ifdef _LP64
  // Check that UseCompressedOops can be set with the max heap size allocated
  // by ergonomics.
  if (MaxHeapSize <= 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);
    }
  }
  // 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");
  // If parallel old was requested, automatically enable parallel scavenge.
  if (UseParallelOldGC && !UseParallelGC && FLAG_IS_DEFAULT(UseParallelGC)) {
    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.
  if (UseParallelGC) {
    FLAG_SET_ERGO(uintx, ParallelGCThreads,
                  Abstract_VM_Version::parallel_worker_threads());

    // 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);
      }
      if (FLAG_IS_DEFAULT(PermMarkSweepDeadRatio)) {
        FLAG_SET_DEFAULT(PermMarkSweepDeadRatio, 5);
      }
    }
  }
}

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());
  }
  no_shared_spaces();

  if (FLAG_IS_DEFAULT(MarkStackSize)) {
    FLAG_SET_DEFAULT(MarkStackSize, 128 * TASKQUEUE_SIZE);
  }
  if (PrintGCDetails && Verbose) {
    tty->print_cr("MarkStackSize: %uk  MarkStackSizeMax: %uk",
      MarkStackSize / K, MarkStackSizeMax / K);
    tty->print_cr("ConcGCThreads: %u", ConcGCThreads);
  }

  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);
  }
}

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 = os::allocatable_physical_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 allocatable_physical_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 initial_heap_size has not been set with InitialHeapSize
  // or -Xms, then set it as fraction of the size of physical memory,
  // respecting the maximum and minimum sizes of the heap.
  if (FLAG_IS_DEFAULT(InitialHeapSize)) {
    julong reasonable_minimum = (julong)(OldSize + NewSize);

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

    reasonable_minimum = os::allocatable_physical_memory(reasonable_minimum);

    julong reasonable_initial = phys_mem / InitialRAMFraction;

    reasonable_initial = MAX2(reasonable_initial, reasonable_minimum);
    reasonable_initial = MIN2(reasonable_initial, (julong)MaxHeapSize);

    reasonable_initial = os::allocatable_physical_memory(reasonable_initial);

    if (PrintGCDetails && Verbose) {
      // Cannot use gclog_or_tty yet.
      tty->print_cr("  Initial heap size " SIZE_FORMAT, (uintx)reasonable_initial);
      tty->print_cr("  Minimum heap size " SIZE_FORMAT, (uintx)reasonable_minimum);
    }
    FLAG_SET_ERGO(uintx, InitialHeapSize, (uintx)reasonable_initial);
    set_min_heap_size((uintx)reasonable_minimum);
  }
}

// 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 (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(DoEscapeAnalysis)) {
    FLAG_SET_DEFAULT(DoEscapeAnalysis, true);
  }
  if (AggressiveOpts && FLAG_IS_DEFAULT(BiasedLockingStartupDelay)) {
    FLAG_SET_DEFAULT(BiasedLockingStartupDelay, 500);
  }
  if (AggressiveOpts && FLAG_IS_DEFAULT(OptimizeStringConcat)) {
    FLAG_SET_DEFAULT(OptimizeStringConcat, true);
  }
  if (AggressiveOpts && FLAG_IS_DEFAULT(OptimizeFill)) {
    FLAG_SET_DEFAULT(OptimizeFill, true);
  }
#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;
}

static void force_serial_gc() {
  FLAG_SET_DEFAULT(UseSerialGC, true);
  FLAG_SET_DEFAULT(UseParNewGC, false);
  FLAG_SET_DEFAULT(UseConcMarkSweepGC, false);
  FLAG_SET_DEFAULT(CMSIncrementalMode, false);  // special CMS suboption
  FLAG_SET_DEFAULT(UseParallelGC, false);
  FLAG_SET_DEFAULT(UseParallelOldGC, false);
  FLAG_SET_DEFAULT(UseG1GC, false);
}

static bool verify_serial_gc_flags() {
  return (UseSerialGC &&
        !(UseParNewGC || (UseConcMarkSweepGC || CMSIncrementalMode) || UseG1GC ||
          UseParallelGC || UseParallelOldGC));
}

// Check consistency of GC selection
bool Arguments::check_gc_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;
}

// 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;

#if ( (defined(COMPILER2) && defined(SPARC)))
  // NOTE: The call to VM_Version_init depends on the fact that VM_Version_init
  // on sparc doesn't require generation of a stub as is the case on, e.g.,
  // x86.  Normally, VM_Version_init must be called from init_globals in
  // init.cpp, which is called by the initial java thread *after* arguments
  // have been parsed.  VM_Version_init gets called twice on sparc.
  extern void VM_Version_init();
  VM_Version_init();
  if (!VM_Version::has_v9()) {
    jio_fprintf(defaultStream::error_stream(),
                "V8 Machine detected, Server requires V9\n");
    status = false;
  }
#endif /* COMPILER2 && SPARC */

  // 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_percentage(AdaptiveSizePolicyWeight,
                              "AdaptiveSizePolicyWeight");
  status = status && verify_percentage(AdaptivePermSizeWeight, "AdaptivePermSizeWeight");
  status = status && verify_percentage(ThresholdTolerance, "ThresholdTolerance");
  status = status && verify_percentage(MinHeapFreeRatio, "MinHeapFreeRatio");
  status = status && verify_percentage(MaxHeapFreeRatio, "MaxHeapFreeRatio");

  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);

  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(intx, 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 && verify_percentage(GCHeapFreeLimit, "GCHeapFreeLimit");

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

  if (_has_alloc_profile) {
    if (UseParallelGC || UseParallelOldGC) {
      jio_fprintf(defaultStream::error_stream(),
                  "error:  invalid argument combination.\n"
                  "Allocation profiling (-Xaprof) cannot be used together with "
                  "Parallel GC (-XX:+UseParallelGC or -XX:+UseParallelOldGC).\n");
      status = false;
    }
    if (UseConcMarkSweepGC) {
      jio_fprintf(defaultStream::error_stream(),
                  "error:  invalid argument combination.\n"
                  "Allocation profiling (-Xaprof) cannot be used together with "
                  "the CMS collector (-XX:+UseConcMarkSweepGC).\n");
      status = false;
    }
  }

  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 (VerifyGCStartAt == 0) {
      warning("Heap verification at start-up disabled "
              "(due to current incompatibility with FLSVerifyAllHeapReferences)");
      VerifyGCStartAt = 1;      // 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: +ExplictGCInvokesConcurrent[AndUnloadsClasses] conflicts"
                " with -UseAsyncConcMarkSweepGC");
    status = false;
  }

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

#ifndef SERIALGC
  if (UseG1GC) {
    status = status && verify_percentage(InitiatingHeapOccupancyPercent,
                                         "InitiatingHeapOccupancyPercent");
    status = status && verify_min_value(G1RefProcDrainInterval, 1,
                                        "G1RefProcDrainInterval");
    status = status && verify_min_value((intx)G1ConcMarkStepDurationMillis, 1,
                                        "G1ConcMarkStepDurationMillis");
  }
#endif

  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();

  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;

  // 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, COMMAND_LINE);
  if (result != JNI_OK) {
    return result;
  }

  if (AggressiveOpts) {
    // Insert alt-rt.jar between user-specified bootclasspath
    // prefix and the default bootclasspath.  os::set_boot_path()
    // uses meta_index_dir as the default bootclasspath directory.
    const char* altclasses_jar = "alt-rt.jar";
    size_t altclasses_path_len = strlen(get_meta_index_dir()) + 1 +
                                 strlen(altclasses_jar);
    char* altclasses_path = NEW_C_HEAP_ARRAY(char, altclasses_path_len);
    strcpy(altclasses_path, get_meta_index_dir());
    strcat(altclasses_path, altclasses_jar);
    scp.add_suffix_to_prefix(altclasses_path);
    scp_assembly_required = true;
    FREE_C_HEAP_ARRAY(char, altclasses_path);
  }

  // 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;
}

jint Arguments::parse_each_vm_init_arg(const JavaVMInitArgs* args,
                                       SysClassPath* scp_p,
                                       bool* scp_assembly_required_p,
                                       FlagValueOrigin 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), 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), pos+1, len2);
        }
#ifdef JVMTI_KERNEL
        if ((strcmp(name, "hprof") == 0) || (strcmp(name, "jdwp") == 0)) {
          warning("profiling and debugging agents are not supported with Kernel VM");
        } else
#endif // JVMTI_KERNEL
        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), tail, len);
        name[len] = '\0';

        char *options = NULL;
        if(pos != NULL) {
          options = strcpy(NEW_C_HEAP_ARRAY(char, strlen(pos + 1) + 1), pos + 1);
        }
#ifdef JVMTI_KERNEL
        if ((strcmp(name, "hprof") == 0) || (strcmp(name, "jdwp") == 0)) {
          warning("profiling and debugging agents are not supported with Kernel VM");
        } else
#endif // JVMTI_KERNEL
        add_init_agent(name, options, is_absolute_path);

      }
    // -javaagent
    } else if (match_option(option, "-javaagent:", &tail)) {
      if(tail != NULL) {
        char *options = strcpy(NEW_C_HEAP_ARRAY(char, strlen(tail) + 1), tail);
        add_init_agent("instrument", options, false);
      }
    // -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_eden_size = 0;
      ArgsRange errcode = parse_memory_size(tail, &long_initial_eden_size, 1);
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid initial eden size: %s\n", option->optionString);
        describe_range_error(errcode);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(uintx, MaxNewSize, (uintx)long_initial_eden_size);
      FLAG_SET_CMDLINE(uintx, NewSize, (uintx)long_initial_eden_size);
    // -Xms
    } else if (match_option(option, "-Xms", &tail)) {
      julong long_initial_heap_size = 0;
      ArgsRange errcode = parse_memory_size(tail, &long_initial_heap_size, 1);
      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;
      }
      FLAG_SET_CMDLINE(uintx, InitialHeapSize, (uintx)long_initial_heap_size);
      // Currently the minimum size and the initial heap sizes are the same.
      set_min_heap_size(InitialHeapSize);
    // -Xmx
    } else if (match_option(option, "-Xmx", &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)) {
      int maxf = (int)(atof(tail) * 100);
      if (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)) {
      int minf = (int)(atof(tail) * 100);
      if (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
    // -Xmaxjitcodesize
    } 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,
                                            (size_t)InitialCodeCacheSize);
      if (errcode != arg_in_range) {
        jio_fprintf(defaultStream::error_stream(),
                    "Invalid maximum code cache size: %s. Should be greater than InitialCodeCacheSize=%dK\n",
                    option->optionString, InitialCodeCacheSize/K);
        describe_range_error(errcode);
        return JNI_EINVAL;
      }
      FLAG_SET_CMDLINE(uintx, ReservedCodeCacheSize, (uintx)long_ReservedCodeCacheSize);
    // -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)) {
#ifndef FPROF_KERNEL
      _has_profile = true;
#else // FPROF_KERNEL
      // do we have to exit?
      warning("Kernel VM does not support flat profiling.");
#endif // FPROF_KERNEL
    // -Xaprof
    } else if (match_option(option, "-Xaprof", &tail)) {
      _has_alloc_profile = true;
    // -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();
      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)) {
        FLAG_SET_CMDLINE(bool, ManagementServer, true);
      }
    // -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)) {
#ifdef TIERED
      FLAG_SET_CMDLINE(bool, DumpSharedSpaces, true);
      set_mode_flags(_int);     // Prevent compilation, which creates objects
#elif defined(COMPILER2)
      vm_exit_during_initialization(
          "Dumping a shared archive is not supported on the Server JVM.", NULL);
#elif defined(KERNEL)
      vm_exit_during_initialization(
          "Dumping a shared archive is not supported on the Kernel JVM.", NULL);
#else
      FLAG_SET_CMDLINE(bool, DumpSharedSpaces, true);
      set_mode_flags(_int);     // Prevent compilation, which creates objects
#endif
    // -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);
      FLAG_SET_CMDLINE(bool, PrintGC, true);
      FLAG_SET_CMDLINE(bool, PrintGCTimeStamps, true);
      FLAG_SET_CMDLINE(bool, TraceClassUnloading, true);

    // JNI hooks
    } else if (match_option(option, "-Xcheck", &tail)) {
      if (!strcmp(tail, ":jni")) {
        CheckJNICalls = true;
      } 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);

      // Make sure that if we have a lot of memory we cap the 32 bit
      // process space.  The 64bit VM version of this function is a nop.
      initHeapSize = os::allocatable_physical_memory(initHeapSize);

      // The perm gen is separate but contiguous with the
      // object heap (and is reserved with it) so subtract it
      // from the heap size.
      if (initHeapSize > MaxPermSize) {
        initHeapSize = initHeapSize - MaxPermSize;
      } else {
        warning("AggressiveHeap and MaxPermSize values may conflict");
      }

      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);
      }

      FLAG_SET_DEFAULT(UseLargePages, true);

      // 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

      // CompilationPolicyChoice=0 causes the server compiler to adopt
      // a more conservative which-method-do-I-compile policy when one
      // of the counters maintained by the interpreter trips.  The
      // result is reduced startup time and improved specjbb and
      // alacrity performance.  Zero is the default, but we set it
      // explicitly here in case the default changes.
      // See runtime/compilationPolicy.*.
      FLAG_SET_CMDLINE(intx, CompilationPolicyChoice, 0);

      // 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);
SOLARIS_ONLY(
    } else if (match_option(option, "-XX:+UsePermISM", &tail)) {
      warning("-XX:+UsePermISM is obsolete.");
      FLAG_SET_CMDLINE(bool, UseISM, true);
    } else if (match_option(option, "-XX:-UsePermISM", &tail)) {
      FLAG_SET_CMDLINE(bool, UseISM, 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)) {
#ifdef SOLARIS
      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 // ndef SOLARIS
      jio_fprintf(defaultStream::error_stream(),
                  "ExtendedDTraceProbes flag is only applicable on Solaris\n");
      return JNI_EINVAL;
#endif // ndef SOLARIS
#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:", &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.
  if (JDK_Version::current().compare_major(6) <= 0 &&
      FLAG_IS_DEFAULT(UseVMInterruptibleIO)) {
    FLAG_SET_DEFAULT(UseVMInterruptibleIO, true);
  }
#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);
  }

#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);
    SOLARIS_ONLY(FLAG_SET_DEFAULT(UseMPSS, false));
    SOLARIS_ONLY(FLAG_SET_DEFAULT(UseISM, false));
  }

  // Tiered compilation is undefined with C1.
  TieredCompilation = false;
#else
  if (!FLAG_IS_DEFAULT(OptoLoopAlignment) && FLAG_IS_DEFAULT(MaxLoopPad)) {
    FLAG_SET_DEFAULT(MaxLoopPad, OptoLoopAlignment-1);
  }
  // Temporary disable bulk zeroing reduction with G1. See CR 6627983.
  if (UseG1GC) {
    FLAG_SET_DEFAULT(ReduceBulkZeroing, false);
  }
#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, ENVIRON_VAR));
  }
  return JNI_OK;
}

void Arguments::set_shared_spaces_flags() {
  // Check whether class data sharing settings conflict with GC, compressed oops
  // or page size, and fix them up.  Explicit sharing options override other
  // settings.
  const bool cannot_share = UseConcMarkSweepGC || CMSIncrementalMode ||
    UseG1GC || UseParNewGC || UseParallelGC || UseParallelOldGC ||
    UseCompressedOops || UseLargePages && FLAG_IS_CMDLINE(UseLargePages);
  const bool must_share = DumpSharedSpaces || RequireSharedSpaces;
  const bool might_share = must_share || UseSharedSpaces;
  if (cannot_share) {
    if (must_share) {
      warning("selecting serial gc and disabling large pages %s"
              "because of %s", "" LP64_ONLY("and compressed oops "),
              DumpSharedSpaces ? "-Xshare:dump" : "-Xshare:on");
      force_serial_gc();
      FLAG_SET_CMDLINE(bool, UseLargePages, false);
      LP64_ONLY(FLAG_SET_CMDLINE(bool, UseCompressedOops, false));
    } else {
      if (UseSharedSpaces && Verbose) {
        warning("turning off use of shared archive because of "
                "choice of garbage collector or large pages");
      }
      no_shared_spaces();
    }
  } else if (UseLargePages && might_share) {
    // Disable large pages to allow shared spaces.  This is sub-optimal, since
    // there may not even be a shared archive to use.
    FLAG_SET_DEFAULT(UseLargePages, false);
  }
}

// Parse entry point called from JNI_CreateJavaVM

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

  // Sharing support
  // Construct the path to the archive
  char jvm_path[JVM_MAXPATHLEN];
  os::jvm_path(jvm_path, sizeof(jvm_path));
#ifdef TIERED
  if (strstr(jvm_path, "client") != NULL) {
    force_client_mode = true;
  }
#endif // TIERED
  char *end = strrchr(jvm_path, *os::file_separator());
  if (end != NULL) *end = '\0';
  char *shared_archive_path = NEW_C_HEAP_ARRAY(char, strlen(jvm_path) +
                                        strlen(os::file_separator()) + 20);
  if (shared_archive_path == NULL) return JNI_ENOMEM;
  strcpy(shared_archive_path, jvm_path);
  strcat(shared_archive_path, os::file_separator());
  strcat(shared_archive_path, "classes");
  DEBUG_ONLY(strcat(shared_archive_path, "_g");)
  strcat(shared_archive_path, ".jsa");
  SharedArchivePath = shared_archive_path;

  // 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.
  bool settings_file_specified = 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();
      vm_exit(0);
    }

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

  // Parse default .hotspotrc settings file
  if (!settings_file_specified) {
    if (!process_settings_file(".hotspotrc", false, args->ignoreUnrecognized)) {
      return JNI_EINVAL;
    }
  }

  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;
  }

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

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

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

  // Set object alignment values.
  set_object_alignment();

#ifdef SERIALGC
  force_serial_gc();
#endif // SERIALGC
#ifdef KERNEL
  no_shared_spaces();
#endif // KERNEL

  // 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);
    }
  }

#ifndef KERNEL
  // Set heap size based on available physical memory
  set_heap_size();
  // 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();
  }
#endif // KERNEL

#ifdef SERIALGC
  assert(verify_serial_gc_flags(), "SerialGC unset");
#endif // SERIALGC

  // 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 (!UseFastLocking || UseHeavyMonitors) {
    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));
#endif // CC_INTERP

#ifdef COMPILER2
  if (!UseBiasedLocking || EmitSync != 0) {
    UseOptoBiasInlining = false;
  }
#endif

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

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

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

  // 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;
}

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);
}

#ifdef KERNEL
char *Arguments::get_kernel_properties() {
  // Find properties starting with kernel and append them to string
  // We need to find out how long they are first because the URL's that they
  // might point to could get long.
  int length = 0;
  SystemProperty* prop;
  for (prop = _system_properties; prop != NULL; prop = prop->next()) {
    if (strncmp(prop->key(), "kernel.", 7 ) == 0) {
      length += (strlen(prop->key()) + strlen(prop->value()) + 5);  // "-D ="
    }
  }
  // Add one for null terminator.
  char *props = AllocateHeap(length + 1, "get_kernel_properties");
  if (length != 0) {
    int pos = 0;
    for (prop = _system_properties; prop != NULL; prop = prop->next()) {
      if (strncmp(prop->key(), "kernel.", 7 ) == 0) {
        jio_snprintf(&props[pos], length-pos,
                     "-D%s=%s ", prop->key(), prop->value());
        pos = strlen(props);
      }
    }
  }
  // null terminate props in case of null
  props[length] = '\0';
  return props;
}
#endif // KERNEL

// 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
}