0
|
1 /*
|
|
2 * Copyright 1999-2006 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 // ciField
|
|
26 //
|
|
27 // This class represents the result of a field lookup in the VM.
|
|
28 // The lookup may not succeed, in which case the information in
|
|
29 // the ciField will be incomplete.
|
|
30 class ciField : public ResourceObj {
|
|
31 CI_PACKAGE_ACCESS
|
|
32 friend class ciEnv;
|
|
33 friend class ciInstanceKlass;
|
|
34 friend class NonStaticFieldFiller;
|
|
35
|
|
36 private:
|
|
37 ciFlags _flags;
|
|
38 ciInstanceKlass* _holder;
|
|
39 ciSymbol* _name;
|
|
40 ciSymbol* _signature;
|
|
41 ciType* _type;
|
|
42 int _offset;
|
|
43 bool _is_constant;
|
|
44 ciInstanceKlass* _known_to_link_with;
|
|
45 ciConstant _constant_value;
|
|
46
|
|
47 // Used for will_link
|
|
48 int _cp_index;
|
|
49
|
|
50 ciType* compute_type();
|
|
51 ciType* compute_type_impl();
|
|
52
|
|
53 ciField(ciInstanceKlass* klass, int index);
|
|
54 ciField(fieldDescriptor* fd);
|
|
55
|
|
56 // shared constructor code
|
|
57 void initialize_from(fieldDescriptor* fd);
|
|
58
|
|
59 // The implementation of the print method.
|
|
60 void print_impl(outputStream* st);
|
|
61
|
|
62 public:
|
|
63 ciFlags flags() { return _flags; }
|
|
64
|
|
65 // Of which klass is this field a member?
|
|
66 //
|
|
67 // Usage note: the declared holder of a field is the class
|
|
68 // referenced by name in the bytecodes. The canonical holder
|
|
69 // is the most general class which holds the field. This
|
|
70 // method returns the canonical holder. The declared holder
|
|
71 // can be accessed via a method in ciBytecodeStream.
|
|
72 //
|
|
73 // Ex.
|
|
74 // class A {
|
|
75 // public int f = 7;
|
|
76 // }
|
|
77 // class B extends A {
|
|
78 // public void test() {
|
|
79 // System.out.println(f);
|
|
80 // }
|
|
81 // }
|
|
82 //
|
|
83 // A java compiler is permitted to compile the access to
|
|
84 // field f as:
|
|
85 //
|
|
86 // getfield B.f
|
|
87 //
|
|
88 // In that case the declared holder of f would be B and
|
|
89 // the canonical holder of f would be A.
|
|
90 ciInstanceKlass* holder() { return _holder; }
|
|
91
|
|
92 // Name of this field?
|
|
93 ciSymbol* name() { return _name; }
|
|
94
|
|
95 // Signature of this field?
|
|
96 ciSymbol* signature() { return _signature; }
|
|
97
|
|
98 // Of what type is this field?
|
|
99 ciType* type() { return (_type == NULL) ? compute_type() : _type; }
|
|
100
|
|
101 // How is this field actually stored in memory?
|
|
102 BasicType layout_type() { return type2field[(_type == NULL) ? T_OBJECT : _type->basic_type()]; }
|
|
103
|
|
104 // How big is this field in memory?
|
|
105 int size_in_bytes() { return type2aelembytes[layout_type()]; }
|
|
106
|
|
107 // What is the offset of this field?
|
|
108 int offset() {
|
|
109 assert(_offset >= 1, "illegal call to offset()");
|
|
110 return _offset;
|
|
111 }
|
|
112
|
|
113 // Same question, explicit units. (Fields are aligned to the byte level.)
|
|
114 int offset_in_bytes() {
|
|
115 return offset();
|
|
116 }
|
|
117
|
|
118 // Is this field shared?
|
|
119 bool is_shared() {
|
|
120 // non-static fields of shared holders are cached
|
|
121 return _holder->is_shared() && !is_static();
|
|
122 }
|
|
123
|
|
124 // Is this field a constant?
|
|
125 //
|
|
126 // Clarification: A field is considered constant if:
|
|
127 // 1. The field is both static and final
|
|
128 // 2. The canonical holder of the field has undergone
|
|
129 // static initialization.
|
|
130 // 3. If the field is an object or array, then the oop
|
|
131 // in question is allocated in perm space.
|
|
132 // 4. The field is not one of the special static/final
|
|
133 // non-constant fields. These are java.lang.System.in
|
|
134 // and java.lang.System.out. Abomination.
|
|
135 //
|
|
136 // Note: the check for case 4 is not yet implemented.
|
|
137 bool is_constant() { return _is_constant; }
|
|
138
|
|
139 // Get the constant value of this field.
|
|
140 ciConstant constant_value() {
|
|
141 assert(is_constant(), "illegal call to constant_value()");
|
|
142 return _constant_value;
|
|
143 }
|
|
144
|
|
145 // Check for link time errors. Accessing a field from a
|
|
146 // certain class via a certain bytecode may or may not be legal.
|
|
147 // This call checks to see if an exception may be raised by
|
|
148 // an access of this field.
|
|
149 //
|
|
150 // Usage note: if the same field is accessed multiple times
|
|
151 // in the same compilation, will_link will need to be checked
|
|
152 // at each point of access.
|
|
153 bool will_link(ciInstanceKlass* accessing_klass,
|
|
154 Bytecodes::Code bc);
|
|
155
|
|
156 // Java access flags
|
|
157 bool is_public () { return flags().is_public(); }
|
|
158 bool is_private () { return flags().is_private(); }
|
|
159 bool is_protected () { return flags().is_protected(); }
|
|
160 bool is_static () { return flags().is_static(); }
|
|
161 bool is_final () { return flags().is_final(); }
|
|
162 bool is_volatile () { return flags().is_volatile(); }
|
|
163 bool is_transient () { return flags().is_transient(); }
|
|
164
|
|
165 // Debugging output
|
|
166 void print();
|
|
167 void print_name_on(outputStream* st);
|
|
168 };
|