view src/share/vm/ci/ciConstant.hpp @ 3979:4dfb2df418f2

6484982: G1: process references during evacuation pauses Summary: G1 now uses two reference processors - one is used by concurrent marking and the other is used by STW GCs (both full and incremental evacuation pauses). In an evacuation pause, the reference processor is embedded into the closures used to scan objects. Doing so causes causes reference objects to be 'discovered' by the reference processor. At the end of the evacuation pause, these discovered reference objects are processed - preserving (and copying) referent objects (and their reachable graphs) as appropriate. Reviewed-by: ysr, jwilhelm, brutisso, stefank, tonyp
author johnc
date Thu, 22 Sep 2011 10:57:37 -0700
parents f6f3bb0ee072
children edb5ab0f3fe5
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/*
 * Copyright (c) 1999, 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.
 *
 */

#ifndef SHARE_VM_CI_CICONSTANT_HPP
#define SHARE_VM_CI_CICONSTANT_HPP

#include "ci/ciClassList.hpp"
#include "ci/ciNullObject.hpp"

// ciConstant
//
// This class represents a constant value.
class ciConstant VALUE_OBJ_CLASS_SPEC {
  friend class VMStructs;
private:
  friend class ciEnv;
  friend class ciField;

  BasicType _type;
  union {
    jint      _int;
    jlong     _long;
    jint      _long_half[2];
    jfloat    _float;
    jdouble   _double;
    ciObject* _object;
  } _value;

public:

  ciConstant() {
    _type = T_ILLEGAL; _value._long = -1;
  }
  ciConstant(BasicType type, jint value) {
    assert(type != T_LONG && type != T_DOUBLE && type != T_FLOAT,
           "using the wrong ciConstant constructor");
    _type = type; _value._int = value;
  }
  ciConstant(jlong value) {
    _type = T_LONG; _value._long = value;
  }
  ciConstant(jfloat value) {
    _type = T_FLOAT; _value._float = value;
  }
  ciConstant(jdouble value) {
    _type = T_DOUBLE; _value._double = value;
  }
  ciConstant(BasicType type, ciObject* p) {
    _type = type; _value._object = p;
  }

  BasicType basic_type() const { return _type; }

  jboolean  as_boolean() {
    assert(basic_type() == T_BOOLEAN, "wrong type");
    return (jboolean)_value._int;
  }
  jchar     as_char() {
    assert(basic_type() == T_CHAR, "wrong type");
    return (jchar)_value._int;
  }
  jbyte     as_byte() {
    assert(basic_type() == T_BYTE, "wrong type");
    return (jbyte)_value._int;
  }
  jshort    as_short() {
    assert(basic_type() == T_SHORT, "wrong type");
    return (jshort)_value._int;
  }
  jint      as_int() {
    assert(basic_type() == T_BOOLEAN || basic_type() == T_CHAR  ||
           basic_type() == T_BYTE    || basic_type() == T_SHORT ||
           basic_type() == T_INT, "wrong type");
    return _value._int;
  }
  jlong     as_long() {
    assert(basic_type() == T_LONG, "wrong type");
    return _value._long;
  }
  jfloat    as_float() {
    assert(basic_type() == T_FLOAT, "wrong type");
    return _value._float;
  }
  jdouble   as_double() {
    assert(basic_type() == T_DOUBLE, "wrong type");
    return _value._double;
  }
  ciObject* as_object() const {
    assert(basic_type() == T_OBJECT || basic_type() == T_ARRAY, "wrong type");
    return _value._object;
  }

  // Debugging output
  void print();
};

#endif // SHARE_VM_CI_CICONSTANT_HPP