1/*
2 * Copyright (c) 1999, 2017, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25#include "precompiled.hpp"
26#include "ci/ciKlass.hpp"
27#include "ci/ciSymbol.hpp"
28#include "ci/ciUtilities.hpp"
29#include "oops/oop.inline.hpp"
30
31// ciKlass
32//
33// This class represents a Klass* in the HotSpot virtual
34// machine.
35
36// ------------------------------------------------------------------
37// ciKlass::ciKlass
38ciKlass::ciKlass(Klass* k) : ciType(k) {
39  assert(get_Klass()->is_klass(), "wrong type");
40  Klass* klass = get_Klass();
41  _layout_helper = klass->layout_helper();
42  Symbol* klass_name = klass->name();
43  assert(klass_name != NULL, "wrong ciKlass constructor");
44  _name = CURRENT_ENV->get_symbol(klass_name);
45}
46
47// ------------------------------------------------------------------
48// ciKlass::ciKlass
49//
50// Nameless klass variant.
51ciKlass::ciKlass(Klass* k, ciSymbol* name) : ciType(k) {
52  assert(get_Klass()->is_klass(), "wrong type");
53  _name = name;
54  _layout_helper = Klass::_lh_neutral_value;
55}
56
57// ------------------------------------------------------------------
58// ciKlass::ciKlass
59//
60// Unloaded klass variant.
61ciKlass::ciKlass(ciSymbol* name, BasicType bt) : ciType(bt) {
62  _name = name;
63  _layout_helper = Klass::_lh_neutral_value;
64}
65
66// ------------------------------------------------------------------
67// ciKlass::is_subtype_of
68bool ciKlass::is_subtype_of(ciKlass* that) {
69  assert(this->is_loaded(), "must be loaded: %s", this->name()->as_quoted_ascii());
70  assert(that->is_loaded(), "must be loaded: %s", that->name()->as_quoted_ascii());
71
72  // Check to see if the klasses are identical.
73  if (this == that) {
74    return true;
75  }
76
77  VM_ENTRY_MARK;
78  Klass* this_klass = get_Klass();
79  Klass* that_klass = that->get_Klass();
80  bool result = this_klass->is_subtype_of(that_klass);
81
82  return result;
83}
84
85// ------------------------------------------------------------------
86// ciKlass::is_subclass_of
87bool ciKlass::is_subclass_of(ciKlass* that) {
88  assert(this->is_loaded(), "must be loaded: %s", this->name()->as_quoted_ascii());
89  assert(that->is_loaded(), "must be loaded: %s", that->name()->as_quoted_ascii());
90
91  GUARDED_VM_ENTRY(return get_Klass()->is_subclass_of(that->get_Klass());)
92}
93
94// ------------------------------------------------------------------
95// ciKlass::super_depth
96juint ciKlass::super_depth() {
97  assert(is_loaded(), "must be loaded");
98
99  VM_ENTRY_MARK;
100  Klass* this_klass = get_Klass();
101  return this_klass->super_depth();
102}
103
104// ------------------------------------------------------------------
105// ciKlass::super_check_offset
106juint ciKlass::super_check_offset() {
107  assert(is_loaded(), "must be loaded");
108
109  VM_ENTRY_MARK;
110  Klass* this_klass = get_Klass();
111  return this_klass->super_check_offset();
112}
113
114// ------------------------------------------------------------------
115// ciKlass::super_of_depth
116ciKlass* ciKlass::super_of_depth(juint i) {
117  assert(is_loaded(), "must be loaded");
118
119  VM_ENTRY_MARK;
120  Klass* this_klass = get_Klass();
121  Klass* super = this_klass->primary_super_of_depth(i);
122  return (super != NULL) ? CURRENT_THREAD_ENV->get_klass(super) : NULL;
123}
124
125// ------------------------------------------------------------------
126// ciKlass::can_be_primary_super
127bool ciKlass::can_be_primary_super() {
128  assert(is_loaded(), "must be loaded");
129
130  VM_ENTRY_MARK;
131  Klass* this_klass = get_Klass();
132  return this_klass->can_be_primary_super();
133}
134
135// ------------------------------------------------------------------
136// ciKlass::least_common_ancestor
137//
138// Get the shared parent of two klasses.
139//
140// Implementation note: this method currently goes "over the wall"
141// and does all of the work on the VM side.  It could be rewritten
142// to use the super() method and do all of the work (aside from the
143// lazy computation of super()) in native mode.  This may be
144// worthwhile if the compiler is repeatedly requesting the same lca
145// computation or possibly if most of the superklasses have already
146// been created as ciObjects anyway.  Something to think about...
147ciKlass*
148ciKlass::least_common_ancestor(ciKlass* that) {
149  assert(is_loaded() && that->is_loaded(), "must be loaded");
150  // Check to see if the klasses are identical.
151  if (this == that) {
152    return this;
153  }
154
155  VM_ENTRY_MARK;
156  Klass* this_klass = get_Klass();
157  Klass* that_klass = that->get_Klass();
158  Klass* lca        = this_klass->LCA(that_klass);
159
160  // Many times the LCA will be either this_klass or that_klass.
161  // Treat these as special cases.
162  if (lca == that_klass) {
163    return that;
164  }
165  if (this_klass == lca) {
166    return this;
167  }
168
169  // Create the ciInstanceKlass for the lca.
170  ciKlass* result =
171    CURRENT_THREAD_ENV->get_klass(lca);
172
173  return result;
174}
175
176// ------------------------------------------------------------------
177// ciKlass::find_klass
178//
179// Find a klass using this klass's class loader.
180ciKlass* ciKlass::find_klass(ciSymbol* klass_name) {
181  assert(is_loaded(), "cannot find_klass through an unloaded klass");
182  return CURRENT_ENV->get_klass_by_name(this,
183                                        klass_name, false);
184}
185
186// ------------------------------------------------------------------
187// ciKlass::java_mirror
188//
189// Get the instance of java.lang.Class corresponding to this klass.
190// If it is an unloaded instance or array klass, return an unloaded
191// mirror object of type Class.
192ciInstance* ciKlass::java_mirror() {
193  GUARDED_VM_ENTRY(
194    if (!is_loaded())
195      return ciEnv::current()->get_unloaded_klass_mirror(this);
196    oop java_mirror = get_Klass()->java_mirror();
197    return CURRENT_ENV->get_instance(java_mirror);
198  )
199}
200
201// ------------------------------------------------------------------
202// ciKlass::modifier_flags
203jint ciKlass::modifier_flags() {
204  assert(is_loaded(), "not loaded");
205  GUARDED_VM_ENTRY(
206    return get_Klass()->modifier_flags();
207  )
208}
209
210// ------------------------------------------------------------------
211// ciKlass::access_flags
212jint ciKlass::access_flags() {
213  assert(is_loaded(), "not loaded");
214  GUARDED_VM_ENTRY(
215    return get_Klass()->access_flags().as_int();
216  )
217}
218
219// ------------------------------------------------------------------
220// ciKlass::print_impl
221//
222// Implementation of the print method
223void ciKlass::print_impl(outputStream* st) {
224  st->print(" name=");
225  print_name_on(st);
226}
227
228// ------------------------------------------------------------------
229// ciKlass::print_name
230//
231// Print the name of this klass
232void ciKlass::print_name_on(outputStream* st) {
233  name()->print_symbol_on(st);
234}
235
236const char* ciKlass::external_name() const {
237  GUARDED_VM_ENTRY(
238    return get_Klass()->external_name();
239  )
240}
241