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.inline.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
38 ciKlass::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.
51 ciKlass::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.
61 ciKlass::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
68 bool 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
87 bool 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
96 juint 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
106 juint 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
116 ciKlass* 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
127 bool 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...
147 ciKlass*
148 ciKlass::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.
180 ciKlass* 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.
192 ciInstance* 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
203 jint 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
212 jint 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
223 void 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
232 void ciKlass::print_name_on(outputStream* st) {
233 name()->print_symbol_on(st);
234 }
235
236 const char* ciKlass::external_name() const {
237 GUARDED_VM_ENTRY(
238 return get_Klass()->external_name();
239 )
240 }