1 /*
  2  * Copyright (c) 1997, 2021, 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 "classfile/vmSymbols.hpp"
 27 #include "memory/resourceArea.hpp"
 28 #include "oops/annotations.hpp"
 29 #include "oops/constantPool.hpp"
 30 #include "oops/instanceKlass.hpp"
 31 #include "oops/klass.inline.hpp"
 32 #include "oops/oop.inline.hpp"
 33 #include "oops/fieldStreams.inline.hpp"
 34 #include "oops/inlineKlass.inline.hpp"
 35 #include "runtime/fieldDescriptor.inline.hpp"
 36 #include "runtime/handles.inline.hpp"
 37 #include "runtime/signature.hpp"
 38 
 39 
 40 oop fieldDescriptor::loader() const {
 41   return _cp->pool_holder()->class_loader();
 42 }
 43 
 44 Symbol* fieldDescriptor::generic_signature() const {
 45   if (!has_generic_signature()) {
 46     return NULL;
 47   }
 48 
 49   int idx = 0;
 50   InstanceKlass* ik = field_holder();
 51   for (AllFieldStream fs(ik); !fs.done(); fs.next()) {
 52     if (idx == _index) {
 53       return fs.generic_signature();
 54     } else {
 55       idx ++;
 56     }
 57   }
 58   assert(false, "should never happen");
 59   return vmSymbols::void_signature(); // return a default value (for code analyzers)
 60 }
 61 
 62 bool fieldDescriptor::is_trusted_final() const {
 63   InstanceKlass* ik = field_holder();
 64   return is_final() && (is_static() || ik->is_hidden() || ik->is_record() || ik->is_inline_klass());
 65 }
 66 
 67 AnnotationArray* fieldDescriptor::annotations() const {
 68   InstanceKlass* ik = field_holder();
 69   Array<AnnotationArray*>* md = ik->fields_annotations();
 70   if (md == NULL)
 71     return NULL;
 72   return md->at(index());
 73 }
 74 
 75 AnnotationArray* fieldDescriptor::type_annotations() const {
 76   InstanceKlass* ik = field_holder();
 77   Array<AnnotationArray*>* type_annos = ik->fields_type_annotations();
 78   if (type_annos == NULL)
 79     return NULL;
 80   return type_annos->at(index());
 81 }
 82 
 83 constantTag fieldDescriptor::initial_value_tag() const {
 84   return constants()->tag_at(initial_value_index());
 85 }
 86 
 87 jint fieldDescriptor::int_initial_value() const {
 88   return constants()->int_at(initial_value_index());
 89 }
 90 
 91 jlong fieldDescriptor::long_initial_value() const {
 92   return constants()->long_at(initial_value_index());
 93 }
 94 
 95 jfloat fieldDescriptor::float_initial_value() const {
 96   return constants()->float_at(initial_value_index());
 97 }
 98 
 99 jdouble fieldDescriptor::double_initial_value() const {
100   return constants()->double_at(initial_value_index());
101 }
102 
103 oop fieldDescriptor::string_initial_value(TRAPS) const {
104   return constants()->uncached_string_at(initial_value_index(), THREAD);
105 }
106 
107 void fieldDescriptor::reinitialize(InstanceKlass* ik, int index) {
108   if (_cp.is_null() || field_holder() != ik) {
109     _cp = constantPoolHandle(Thread::current(), ik->constants());
110     // _cp should now reference ik's constant pool; i.e., ik is now field_holder.
111     assert(field_holder() == ik, "must be already initialized to this class");
112   }
113   FieldInfo* f = ik->field(index);
114   _access_flags = accessFlags_from(f->access_flags());
115   guarantee(f->name_index() != 0 && f->signature_index() != 0, "bad constant pool index for fieldDescriptor");
116   _index = index;
117   verify();
118 }
119 
120 #ifndef PRODUCT
121 
122 void fieldDescriptor::verify() const {
123   if (_cp.is_null()) {
124     assert(_index == badInt, "constructor must be called");  // see constructor
125   } else {
126     assert(_index >= 0, "good index");
127     assert(access_flags().is_internal() ||
128            _index < field_holder()->java_fields_count(), "oob");
129   }
130 }
131 
132 #endif /* PRODUCT */
133 
134 void fieldDescriptor::print_on(outputStream* st) const {
135   access_flags().print_on(st);
136   if (access_flags().is_internal()) st->print("internal ");
137   name()->print_value_on(st);
138   st->print(" ");
139   signature()->print_value_on(st);
140   st->print(" @%d ", offset());
141   if (WizardMode && has_initial_value()) {
142     st->print("(initval ");
143     constantTag t = initial_value_tag();
144     if (t.is_int()) {
145       st->print("int %d)", int_initial_value());
146     } else if (t.is_long()){
147       st->print_jlong(long_initial_value());
148     } else if (t.is_float()){
149       st->print("float %f)", float_initial_value());
150     } else if (t.is_double()){
151       st->print("double %lf)", double_initial_value());
152     }
153   }
154 }
155 
156 void fieldDescriptor::print() const { print_on(tty); }
157 
158 void fieldDescriptor::print_on_for(outputStream* st, oop obj) {
159   BasicType ft = field_type();
160   if (ft != T_PRIMITIVE_OBJECT) {
161     print_on(st);
162     st->print(" ");
163   }
164   jint as_int = 0;
165   switch (ft) {
166     case T_BYTE:
167       st->print("%d", obj->byte_field(offset()));
168       break;
169     case T_CHAR:
170       {
171         jchar c = obj->char_field(offset());
172         st->print("%c %d", isprint(c) ? c : ' ', c);
173       }
174       break;
175     case T_DOUBLE:
176       st->print("%lf", obj->double_field(offset()));
177       break;
178     case T_FLOAT:
179       st->print("%f", obj->float_field(offset()));
180       break;
181     case T_INT:
182       st->print("%d", obj->int_field(offset()));
183       break;
184     case T_LONG:
185       st->print_jlong(obj->long_field(offset()));
186       break;
187     case T_SHORT:
188       st->print("%d", obj->short_field(offset()));
189       break;
190     case T_BOOLEAN:
191       st->print("%s", obj->bool_field(offset()) ? "true" : "false");
192       break;
193     case T_PRIMITIVE_OBJECT:
194       if (is_inlined()) {
195         // Print fields of inlined fields (recursively)
196         InlineKlass* vk = InlineKlass::cast(field_holder()->get_inline_type_field_klass(index()));
197         int field_offset = offset() - vk->first_field_offset();
198         obj = cast_to_oop(cast_from_oop<address>(obj) + field_offset);
199         st->print_cr("Inline type field inlined '%s':", vk->name()->as_C_string());
200         FieldPrinter print_field(st, obj);
201         vk->do_nonstatic_fields(&print_field);
202         return; // Do not print underlying representation
203       }
204       // inline type field not inlined, fall through
205     case T_ARRAY:
206     case T_OBJECT:
207       if (obj->obj_field(offset()) != NULL) {
208         obj->obj_field(offset())->print_value_on(st);
209       } else {
210         st->print("NULL");
211       }
212       break;
213     default:
214       ShouldNotReachHere();
215       break;
216   }
217 
218   // Print a hint as to the underlying integer representation.
219   if (is_reference_type(ft)) {
220 #ifdef _LP64
221     if (UseCompressedOops) {
222       st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset()));
223     } else {
224       st->print(" (" INT64_FORMAT_X_0 ")", (int64_t)obj->long_field(offset()));
225     }
226 #else
227     st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset()));
228 #endif
229   } else { // Primitives
230     switch (ft) {
231       case T_LONG:    st->print(" (" INT64_FORMAT_X_0 ")", (int64_t)obj->long_field(offset())); break;
232       case T_DOUBLE:  st->print(" (" INT64_FORMAT_X_0 ")", (int64_t)obj->long_field(offset())); break;
233       case T_BYTE:    st->print(" (" INT8_FORMAT_X_0  ")", obj->byte_field(offset()));          break;
234       case T_CHAR:    st->print(" (" INT16_FORMAT_X_0 ")", obj->char_field(offset()));          break;
235       case T_FLOAT:   st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset()));           break;
236       case T_INT:     st->print(" (" INT32_FORMAT_X_0 ")", obj->int_field(offset()));           break;
237       case T_SHORT:   st->print(" (" INT16_FORMAT_X_0 ")", obj->short_field(offset()));         break;
238       case T_BOOLEAN: st->print(" (" INT8_FORMAT_X_0  ")", obj->bool_field(offset()));          break;
239     default:
240       ShouldNotReachHere();
241       break;
242     }
243   }
244   st->cr();
245 }