1 /*
2 * Copyright (c) 1999, 2010, 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 klassOop in the HotSpot virtual
34 // machine.
35
36 // ------------------------------------------------------------------
37 // ciKlass::ciKlass
38 ciKlass::ciKlass(KlassHandle h_k) : ciType(h_k) {
39 assert(get_oop()->is_klass(), "wrong type");
40 Klass* k = get_Klass();
41 _layout_helper = k->layout_helper();
42 symbolOop klass_name = k->name();
43 assert(klass_name != NULL, "wrong ciKlass constructor");
44 _name = CURRENT_ENV->get_object(klass_name)->as_symbol();
45 }
46
47 // ------------------------------------------------------------------
48 // ciKlass::ciKlass
49 //
50 // Nameless klass variant.
51 ciKlass::ciKlass(KlassHandle h_k, ciSymbol* name) : ciType(h_k) {
52 assert(get_oop()->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.
61 ciKlass::ciKlass(ciSymbol* name, ciKlass* klass) : ciType(klass) {
62 _name = name;
63 _layout_helper = Klass::_lh_neutral_value;
64 }
65
66 // ------------------------------------------------------------------
67 // ciKlass::is_subtype_of
68 bool ciKlass::is_subtype_of(ciKlass* that) {
69 assert(is_loaded() && that->is_loaded(), "must be loaded");
70 assert(is_java_klass() && that->is_java_klass(), "must be java klasses");
71 // Check to see if the klasses are identical.
72 if (this == that) {
73 return true;
74 }
75
76 VM_ENTRY_MARK;
77 Klass* this_klass = get_Klass();
78 klassOop that_klass = that->get_klassOop();
79 bool result = this_klass->is_subtype_of(that_klass);
80
81 return result;
82 }
83
84 // ------------------------------------------------------------------
85 // ciKlass::is_subclass_of
86 bool ciKlass::is_subclass_of(ciKlass* that) {
87 assert(is_loaded() && that->is_loaded(), "must be loaded");
88 assert(is_java_klass() && that->is_java_klass(), "must be java klasses");
89 // Check to see if the klasses are identical.
90
91 VM_ENTRY_MARK;
92 Klass* this_klass = get_Klass();
93 klassOop that_klass = that->get_klassOop();
94 bool result = this_klass->is_subclass_of(that_klass);
95
96 return result;
97 }
98
99 // ------------------------------------------------------------------
100 // ciKlass::super_depth
101 juint ciKlass::super_depth() {
102 assert(is_loaded(), "must be loaded");
103 assert(is_java_klass(), "must be java klasses");
104
105 VM_ENTRY_MARK;
106 Klass* this_klass = get_Klass();
107 return this_klass->super_depth();
108 }
109
110 // ------------------------------------------------------------------
111 // ciKlass::super_check_offset
112 juint ciKlass::super_check_offset() {
113 assert(is_loaded(), "must be loaded");
114 assert(is_java_klass(), "must be java klasses");
115
116 VM_ENTRY_MARK;
117 Klass* this_klass = get_Klass();
118 return this_klass->super_check_offset();
119 }
120
121 // ------------------------------------------------------------------
122 // ciKlass::super_of_depth
123 ciKlass* ciKlass::super_of_depth(juint i) {
124 assert(is_loaded(), "must be loaded");
125 assert(is_java_klass(), "must be java klasses");
126
127 VM_ENTRY_MARK;
128 Klass* this_klass = get_Klass();
129 klassOop super = this_klass->primary_super_of_depth(i);
130 return (super != NULL) ? CURRENT_THREAD_ENV->get_object(super)->as_klass() : NULL;
131 }
132
133 // ------------------------------------------------------------------
134 // ciKlass::can_be_primary_super
135 bool ciKlass::can_be_primary_super() {
136 assert(is_loaded(), "must be loaded");
137 assert(is_java_klass(), "must be java klasses");
138
139 VM_ENTRY_MARK;
140 Klass* this_klass = get_Klass();
141 return this_klass->can_be_primary_super();
142 }
143
144 // ------------------------------------------------------------------
145 // ciKlass::least_common_ancestor
146 //
147 // Get the shared parent of two klasses.
148 //
149 // Implementation note: this method currently goes "over the wall"
150 // and does all of the work on the VM side. It could be rewritten
151 // to use the super() method and do all of the work (aside from the
152 // lazy computation of super()) in native mode. This may be
153 // worthwhile if the compiler is repeatedly requesting the same lca
154 // computation or possibly if most of the superklasses have already
155 // been created as ciObjects anyway. Something to think about...
156 ciKlass*
157 ciKlass::least_common_ancestor(ciKlass* that) {
158 assert(is_loaded() && that->is_loaded(), "must be loaded");
159 assert(is_java_klass() && that->is_java_klass(), "must be java klasses");
160 // Check to see if the klasses are identical.
161 if (this == that) {
162 return this;
163 }
164
165 VM_ENTRY_MARK;
166 Klass* this_klass = get_Klass();
167 Klass* that_klass = that->get_Klass();
168 Klass* lca = this_klass->LCA(that_klass);
169
170 // Many times the LCA will be either this_klass or that_klass.
171 // Treat these as special cases.
172 if (lca == that_klass) {
173 return that;
174 }
175 if (this_klass == lca) {
176 return this;
177 }
178
179 // Create the ciInstanceKlass for the lca.
180 ciKlass* result =
181 CURRENT_THREAD_ENV->get_object(lca->as_klassOop())->as_klass();
182
183 return result;
184 }
185
186 // ------------------------------------------------------------------
187 // ciKlass::find_klass
188 //
189 // Find a klass using this klass's class loader.
190 ciKlass* ciKlass::find_klass(ciSymbol* klass_name) {
191 assert(is_loaded(), "cannot find_klass through an unloaded klass");
192 return CURRENT_ENV->get_klass_by_name(this,
193 klass_name, false);
194 }
195
196 // ------------------------------------------------------------------
197 // ciKlass::java_mirror
198 //
199 // Get the instance of java.lang.Class corresponding to this klass.
200 // If it is an unloaded instance or array klass, return an unloaded
201 // mirror object of type Class.
202 ciInstance* ciKlass::java_mirror() {
203 GUARDED_VM_ENTRY(
204 if (!is_loaded())
205 return ciEnv::current()->get_unloaded_klass_mirror(this);
206 oop java_mirror = get_Klass()->java_mirror();
207 return CURRENT_ENV->get_object(java_mirror)->as_instance();
208 )
209 }
210
211 // ------------------------------------------------------------------
212 // ciKlass::modifier_flags
213 jint ciKlass::modifier_flags() {
214 assert(is_loaded(), "not loaded");
215 GUARDED_VM_ENTRY(
216 return get_Klass()->modifier_flags();
217 )
218 }
219
220 // ------------------------------------------------------------------
221 // ciKlass::access_flags
222 jint ciKlass::access_flags() {
223 assert(is_loaded(), "not loaded");
224 GUARDED_VM_ENTRY(
225 return get_Klass()->access_flags().as_int();
226 )
227 }
228
229 // ------------------------------------------------------------------
230 // ciKlass::print_impl
231 //
232 // Implementation of the print method
233 void ciKlass::print_impl(outputStream* st) {
234 st->print(" name=");
235 print_name_on(st);
236 }
237
238 // ------------------------------------------------------------------
239 // ciKlass::print_name
240 //
241 // Print the name of this klass
242 void ciKlass::print_name_on(outputStream* st) {
243 name()->print_symbol_on(st);
244 }