ciInstance.cpp revision 0:a61af66fc99e 
1/*
2 * Copyright 1999-2005 Sun Microsystems, Inc.  All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25#include "incls/_precompiled.incl"
26#include "incls/_ciInstance.cpp.incl"
27
28// ciInstance
29//
30// This class represents an instanceOop in the HotSpot virtual
31// machine.
32
33// ------------------------------------------------------------------
34// ciObject::java_mirror_type
35ciType* ciInstance::java_mirror_type() {
36  VM_ENTRY_MARK;
37  oop m = get_oop();
38  // Return NULL if it is not java.lang.Class.
39  if (m == NULL || m->klass() != SystemDictionary::class_klass()) {
40    return NULL;
41  }
42  // Return either a primitive type or a klass.
43  if (java_lang_Class::is_primitive(m)) {
44    return ciType::make(java_lang_Class::primitive_type(m));
45  } else {
46    klassOop k = java_lang_Class::as_klassOop(m);
47    assert(k != NULL, "");
48    return CURRENT_THREAD_ENV->get_object(k)->as_klass();
49  }
50}
51
52// ------------------------------------------------------------------
53// ciInstance::field_value
54//
55// Constant value of a field.
56ciConstant ciInstance::field_value(ciField* field) {
57  assert(is_loaded() &&
58         field->holder()->is_loaded() &&
59         klass()->is_subclass_of(field->holder()),
60         "invalid access");
61  VM_ENTRY_MARK;
62  ciConstant result;
63  oop obj = get_oop();
64  assert(obj != NULL, "bad oop");
65  BasicType field_btype = field->type()->basic_type();
66  int offset = field->offset();
67
68  switch(field_btype) {
69  case T_BYTE:
70    return ciConstant(field_btype, obj->byte_field(offset));
71    break;
72  case T_CHAR:
73    return ciConstant(field_btype, obj->char_field(offset));
74    break;
75  case T_SHORT:
76    return ciConstant(field_btype, obj->short_field(offset));
77    break;
78  case T_BOOLEAN:
79    return ciConstant(field_btype, obj->bool_field(offset));
80    break;
81  case T_INT:
82    return ciConstant(field_btype, obj->int_field(offset));
83    break;
84  case T_FLOAT:
85    return ciConstant(obj->float_field(offset));
86    break;
87  case T_DOUBLE:
88    return ciConstant(obj->double_field(offset));
89    break;
90  case T_LONG:
91    return ciConstant(obj->long_field(offset));
92    break;
93  case T_OBJECT:
94  case T_ARRAY:
95    {
96      oop o = obj->obj_field(offset);
97
98      // A field will be "constant" if it is known always to be
99      // a non-null reference to an instance of a particular class,
100      // or to a particular array.  This can happen even if the instance
101      // or array is not perm.  In such a case, an "unloaded" ciArray
102      // or ciInstance is created.  The compiler may be able to use
103      // information about the object's class (which is exact) or length.
104
105      if (o == NULL) {
106        return ciConstant(field_btype, ciNullObject::make());
107      } else {
108        return ciConstant(field_btype, CURRENT_ENV->get_object(o));
109      }
110    }
111  }
112  ShouldNotReachHere();
113  // to shut up the compiler
114  return ciConstant();
115}
116
117// ------------------------------------------------------------------
118// ciInstance::field_value_by_offset
119//
120// Constant value of a field at the specified offset.
121ciConstant ciInstance::field_value_by_offset(int field_offset) {
122  ciInstanceKlass* ik = klass()->as_instance_klass();
123  ciField* field = ik->get_field_by_offset(field_offset, false);
124  return field_value(field);
125}
126
127// ------------------------------------------------------------------
128// ciInstance::print_impl
129//
130// Implementation of the print method.
131void ciInstance::print_impl(outputStream* st) {
132  st->print(" type=");
133  klass()->print(st);
134}
135