1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5  * This code is free software; you can redistribute it and/or modify it
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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).
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15  * You should have received a copy of the GNU General Public License version
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17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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24 
25 #include "precompiled.hpp"
26 #include "ci/ciInstanceKlass.hpp"
27 #include "ci/ciObjArrayKlass.hpp"
28 #include "ci/ciSymbol.hpp"
29 #include "ci/ciUtilities.inline.hpp"
30 #include "oops/objArrayKlass.hpp"
31 
32 // ciObjArrayKlass
33 //
34 // This class represents a Klass* in the HotSpot virtual machine
35 // whose Klass part is an ObjArrayKlass.
36 
37 // ------------------------------------------------------------------
38 // ciObjArrayKlass::ciObjArrayKlass
39 //
40 // Constructor for loaded object array klasses.
ciObjArrayKlass(Klass * k)41 ciObjArrayKlass::ciObjArrayKlass(Klass* k) : ciArrayKlass(k) {
42   assert(get_Klass()->is_objArray_klass(), "wrong type");
43   Klass* element_Klass = get_ObjArrayKlass()->bottom_klass();
44   _base_element_klass = CURRENT_ENV->get_klass(element_Klass);
45   assert(_base_element_klass->is_instance_klass() ||
46          _base_element_klass->is_type_array_klass(), "bad base klass");
47   if (dimension() == 1) {
48     _element_klass = _base_element_klass;
49   } else {
50     _element_klass = NULL;
51   }
52   if (!ciObjectFactory::is_initialized()) {
53     assert(_element_klass->is_java_lang_Object(), "only arrays of object are shared");
54   }
55 }
56 
57 // ------------------------------------------------------------------
58 // ciObjArrayKlass::ciObjArrayKlass
59 //
60 // Constructor for unloaded object array klasses.
ciObjArrayKlass(ciSymbol * array_name,ciKlass * base_element_klass,int dimension)61 ciObjArrayKlass::ciObjArrayKlass(ciSymbol* array_name,
62                                  ciKlass* base_element_klass,
63                                  int dimension)
64   : ciArrayKlass(array_name,
65                  dimension, T_OBJECT) {
66     _base_element_klass = base_element_klass;
67     assert(_base_element_klass->is_instance_klass() ||
68            _base_element_klass->is_type_array_klass(), "bad base klass");
69     if (dimension == 1) {
70       _element_klass = base_element_klass;
71     } else {
72       _element_klass = NULL;
73     }
74 }
75 
76 // ------------------------------------------------------------------
77 // ciObjArrayKlass::element_klass
78 //
79 // What is the one-level element type of this array?
element_klass()80 ciKlass* ciObjArrayKlass::element_klass() {
81   if (_element_klass == NULL) {
82     assert(dimension() > 1, "_element_klass should not be NULL");
83     // Produce the element klass.
84     if (is_loaded()) {
85       VM_ENTRY_MARK;
86       Klass* element_Klass = get_ObjArrayKlass()->element_klass();
87       _element_klass = CURRENT_THREAD_ENV->get_klass(element_Klass);
88     } else {
89       VM_ENTRY_MARK;
90       // We are an unloaded array klass.  Attempt to fetch our
91       // element klass by name.
92       _element_klass = CURRENT_THREAD_ENV->get_klass_by_name_impl(
93                           this,
94                           constantPoolHandle(),
95                           construct_array_name(base_element_klass()->name(),
96                                                dimension() - 1),
97                           false);
98     }
99   }
100   return _element_klass;
101 }
102 
103 // ------------------------------------------------------------------
104 // ciObjArrayKlass::construct_array_name
105 //
106 // Build an array name from an element name and a dimension.
construct_array_name(ciSymbol * element_name,int dimension)107 ciSymbol* ciObjArrayKlass::construct_array_name(ciSymbol* element_name,
108                                                 int dimension) {
109   EXCEPTION_CONTEXT;
110   int element_len = element_name->utf8_length();
111   int buflen = dimension + element_len + 3;  // '['+ + 'L'? + (element) + ';'? + '\0'
112   char* name = CURRENT_THREAD_ENV->name_buffer(buflen);
113   int pos = 0;
114   for ( ; pos < dimension; pos++) {
115     name[pos] = JVM_SIGNATURE_ARRAY;
116   }
117   Symbol* base_name_sym = element_name->get_symbol();
118 
119   if (Signature::is_array(base_name_sym) ||
120       Signature::has_envelope(base_name_sym)) {
121     strncpy(&name[pos], (char*)element_name->base(), element_len);
122     name[pos + element_len] = '\0';
123   } else {
124     name[pos++] = JVM_SIGNATURE_CLASS;
125     strncpy(&name[pos], (char*)element_name->base(), element_len);
126     name[pos + element_len] = JVM_SIGNATURE_ENDCLASS;
127     name[pos + element_len + 1] = '\0';
128   }
129   return ciSymbol::make(name);
130 }
131 
132 // ------------------------------------------------------------------
133 // ciObjArrayKlass::make_impl
134 //
135 // Implementation of make.
make_impl(ciKlass * element_klass)136 ciObjArrayKlass* ciObjArrayKlass::make_impl(ciKlass* element_klass) {
137 
138   if (element_klass->is_loaded()) {
139     EXCEPTION_CONTEXT;
140     // The element klass is loaded
141     Klass* array = element_klass->get_Klass()->array_klass(THREAD);
142     if (HAS_PENDING_EXCEPTION) {
143       CLEAR_PENDING_EXCEPTION;
144       CURRENT_THREAD_ENV->record_out_of_memory_failure();
145       return ciEnv::unloaded_ciobjarrayklass();
146     }
147     return CURRENT_THREAD_ENV->get_obj_array_klass(array);
148   }
149 
150   // The array klass was unable to be made or the element klass was
151   // not loaded.
152   ciSymbol* array_name = construct_array_name(element_klass->name(), 1);
153   if (array_name == ciEnv::unloaded_cisymbol()) {
154     return ciEnv::unloaded_ciobjarrayklass();
155   }
156   return
157     CURRENT_ENV->get_unloaded_klass(element_klass, array_name)
158                         ->as_obj_array_klass();
159 }
160 
161 // ------------------------------------------------------------------
162 // ciObjArrayKlass::make
163 //
164 // Make an array klass corresponding to the specified primitive type.
make(ciKlass * element_klass)165 ciObjArrayKlass* ciObjArrayKlass::make(ciKlass* element_klass) {
166   GUARDED_VM_ENTRY(return make_impl(element_klass);)
167 }
168 
exact_klass()169 ciKlass* ciObjArrayKlass::exact_klass() {
170   ciType* base = base_element_type();
171   if (base->is_instance_klass()) {
172     ciInstanceKlass* ik = base->as_instance_klass();
173     if (ik->exact_klass() != NULL) {
174       return this;
175     }
176   } else if (base->is_primitive_type()) {
177     return this;
178   }
179   return NULL;
180 }
181