view src/share/vm/ci/ciType.cpp @ 20543:e7d0505c8a30

8059758: Footprint regressions with JDK-8038423 Summary: Changes in JDK-8038423 always initialize (zero out) virtual memory used for auxiliary data structures. This causes a footprint regression for G1 in startup benchmarks. This is because they do not touch that memory at all, so the operating system does not actually commit these pages. The fix is to, if the initialization value of the data structures matches the default value of just committed memory (=0), do not do anything. Reviewed-by: jwilhelm, brutisso
author tschatzl
date Fri, 10 Oct 2014 15:51:58 +0200
parents 78bbf4d43a14
children 52b4284cb496
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/*
 * Copyright (c) 2000, 2014, 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 "ci/ciEnv.hpp"
#include "ci/ciType.hpp"
#include "ci/ciUtilities.hpp"
#include "classfile/systemDictionary.hpp"
#include "oops/oop.inline.hpp"

ciType* ciType::_basic_types[T_CONFLICT+1];

// ciType
//
// This class represents either a class (T_OBJECT), array (T_ARRAY),
// or one of the primitive types such as T_INT.

// ------------------------------------------------------------------
// ciType::ciType
//
ciType::ciType(BasicType basic_type) : ciMetadata() {
  assert(basic_type >= T_BOOLEAN && basic_type <= T_CONFLICT, "range check");
  _basic_type = basic_type;
}

ciType::ciType(KlassHandle k) : ciMetadata(k()) {
  _basic_type = k()->oop_is_array() ? T_ARRAY : T_OBJECT;
}


// ------------------------------------------------------------------
// ciType::is_subtype_of
//
bool ciType::is_subtype_of(ciType* type) {
  if (this == type)  return true;
  if (is_klass() && type->is_klass())
    return this->as_klass()->is_subtype_of(type->as_klass());
  return false;
}

// ------------------------------------------------------------------
// ciType::name
//
// Return the name of this type
const char* ciType::name() {
  if (is_primitive_type()) {
    return type2name(basic_type());
  } else {
    assert(is_klass(), "must be");
    return as_klass()->name()->as_utf8();
  }
}

// ------------------------------------------------------------------
// ciType::print_impl
//
// Implementation of the print method.
void ciType::print_impl(outputStream* st) {
  st->print(" type=");
  print_name_on(st);
}

// ------------------------------------------------------------------
// ciType::print_name
//
// Print the name of this type
void ciType::print_name_on(outputStream* st) {
  ResourceMark rm;
  st->print("%s", name());
}



// ------------------------------------------------------------------
// ciType::java_mirror
//
ciInstance* ciType::java_mirror() {
  VM_ENTRY_MARK;
  return CURRENT_THREAD_ENV->get_instance(Universe::java_mirror(basic_type()));
}

// ------------------------------------------------------------------
// ciType::box_klass
//
ciKlass* ciType::box_klass() {
  if (!is_primitive_type())  return this->as_klass();  // reference types are "self boxing"

  // Void is "boxed" with a null.
  if (basic_type() == T_VOID)  return NULL;

  VM_ENTRY_MARK;
  return CURRENT_THREAD_ENV->get_instance_klass(SystemDictionary::box_klass(basic_type()));
}


// ------------------------------------------------------------------
// ciType::make
//
// Produce the ciType for a given primitive BasicType.
// As a bonus, produce the right reference type for T_OBJECT.
// Does not work on T_ARRAY.
ciType* ciType::make(BasicType t) {
  // short, etc.
  // Note: Bare T_ADDRESS means a raw pointer type, not a return_address.
  assert((uint)t < T_CONFLICT+1, "range check");
  if (t == T_OBJECT)  return ciEnv::_Object_klass;  // java/lang/Object
  assert(_basic_types[t] != NULL, "domain check");
  return _basic_types[t];
}

// ciReturnAddress
//
// This class represents the type of a specific return address in the
// bytecodes.

// ------------------------------------------------------------------
// ciReturnAddress::ciReturnAddress
//
ciReturnAddress::ciReturnAddress(int bci) : ciType(T_ADDRESS) {
  assert(0 <= bci, "bci cannot be negative");
  _bci = bci;
}

// ------------------------------------------------------------------
// ciReturnAddress::print_impl
//
// Implementation of the print method.
void ciReturnAddress::print_impl(outputStream* st) {
  st->print(" bci=%d", _bci);
}

// ------------------------------------------------------------------
// ciReturnAddress::make
ciReturnAddress* ciReturnAddress::make(int bci) {
  GUARDED_VM_ENTRY(return CURRENT_ENV->get_return_address(bci);)
}