1 /* 2 * Copyright (c) 1999, 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 "ci/ciInstanceKlass.hpp" 27 #include "ci/ciObjArrayKlass.hpp" 28 #include "ci/ciSymbol.hpp" 29 #include "ci/ciUtilities.inline.hpp" 30 #include "oops/inlineKlass.inline.hpp" 31 #include "oops/objArrayKlass.hpp" 32 #include "runtime/signature.hpp" 33 34 // ciObjArrayKlass 35 // 36 // This class represents a Klass* in the HotSpot virtual machine 37 // whose Klass part is an ObjArrayKlass. 38 39 // ------------------------------------------------------------------ 40 // ciObjArrayKlass::ciObjArrayKlass 41 // 42 // Constructor for loaded object array klasses. 43 ciObjArrayKlass::ciObjArrayKlass(Klass* k) : ciArrayKlass(k) { 44 assert(get_Klass()->is_objArray_klass(), "wrong type"); 45 Klass* element_Klass = get_ObjArrayKlass()->bottom_klass(); 46 _base_element_klass = CURRENT_ENV->get_klass(element_Klass); 47 assert(_base_element_klass->is_instance_klass() || 48 _base_element_klass->is_type_array_klass(), "bad base klass"); 49 if (dimension() == 1) { 50 _element_klass = _base_element_klass; 51 } else { 52 _element_klass = NULL; 53 } 54 if (!ciObjectFactory::is_initialized()) { 55 assert(_element_klass->is_java_lang_Object(), "only arrays of object are shared"); 56 } 57 _null_free = k->name()->is_Q_array_signature() && k->name()->char_at(1) == JVM_SIGNATURE_PRIMITIVE_OBJECT; 58 } 59 60 // ------------------------------------------------------------------ 61 // ciObjArrayKlass::ciObjArrayKlass 62 // 63 // Constructor for unloaded object array klasses. 64 ciObjArrayKlass::ciObjArrayKlass(ciSymbol* array_name, 65 ciKlass* base_element_klass, 66 int dimension) 67 : ciArrayKlass(array_name, 68 dimension, T_OBJECT) { 69 _base_element_klass = base_element_klass; 70 assert(_base_element_klass->is_instance_klass() || 71 _base_element_klass->is_type_array_klass() || 72 _base_element_klass->is_flat_array_klass(), "bad base klass"); 73 if (dimension == 1) { 74 _element_klass = base_element_klass; 75 } else { 76 _element_klass = NULL; 77 } 78 _null_free = array_name->is_Q_array_signature() && array_name->char_at(1) == JVM_SIGNATURE_PRIMITIVE_OBJECT; 79 } 80 81 // ------------------------------------------------------------------ 82 // ciObjArrayKlass::element_klass 83 // 84 // What is the one-level element type of this array? 85 ciKlass* ciObjArrayKlass::element_klass() { 86 if (_element_klass == NULL) { 87 assert(dimension() > 1, "_element_klass should not be NULL"); 88 // Produce the element klass. 89 if (is_loaded()) { 90 VM_ENTRY_MARK; 91 Klass* element_Klass = get_ObjArrayKlass()->element_klass(); 92 _element_klass = CURRENT_THREAD_ENV->get_klass(element_Klass); 93 } else { 94 VM_ENTRY_MARK; 95 // We are an unloaded array klass. Attempt to fetch our 96 // element klass by name. 97 _element_klass = CURRENT_THREAD_ENV->get_klass_by_name_impl( 98 this, 99 constantPoolHandle(), 100 construct_array_name(base_element_klass()->name(), 101 dimension() - 1), 102 false); 103 } 104 } 105 return _element_klass; 106 } 107 108 // ------------------------------------------------------------------ 109 // ciObjArrayKlass::construct_array_name 110 // 111 // Build an array name from an element name and a dimension. 112 ciSymbol* ciObjArrayKlass::construct_array_name(ciSymbol* element_name, 113 int dimension) { 114 EXCEPTION_CONTEXT; 115 int element_len = element_name->utf8_length(); 116 int buflen = dimension + element_len + 3; // '['+ + 'L'? + (element) + ';'? + '\0' 117 char* name = CURRENT_THREAD_ENV->name_buffer(buflen); 118 int pos = 0; 119 for ( ; pos < dimension; pos++) { 120 name[pos] = JVM_SIGNATURE_ARRAY; 121 } 122 Symbol* base_name_sym = element_name->get_symbol(); 123 assert(base_name_sym->char_at(0) != JVM_SIGNATURE_PRIMITIVE_OBJECT, "unloaded array klass element should not have Q-type"); 124 if (Signature::is_array(base_name_sym) || 125 Signature::has_envelope(base_name_sym)) { 126 strncpy(&name[pos], (char*)element_name->base(), element_len); 127 name[pos + element_len] = '\0'; 128 } else { 129 name[pos++] = JVM_SIGNATURE_CLASS; 130 strncpy(&name[pos], (char*)element_name->base(), element_len); 131 name[pos + element_len] = JVM_SIGNATURE_ENDCLASS; 132 name[pos + element_len + 1] = '\0'; 133 } 134 return ciSymbol::make(name); 135 } 136 137 // ------------------------------------------------------------------ 138 // ciObjArrayKlass::make_impl 139 // 140 // Implementation of make. 141 ciObjArrayKlass* ciObjArrayKlass::make_impl(ciKlass* element_klass) { 142 if (element_klass->is_loaded()) { 143 EXCEPTION_CONTEXT; 144 // The element klass is loaded 145 Klass* array = element_klass->get_Klass()->array_klass(THREAD); 146 if (HAS_PENDING_EXCEPTION) { 147 CLEAR_PENDING_EXCEPTION; 148 CURRENT_THREAD_ENV->record_out_of_memory_failure(); 149 return ciEnv::unloaded_ciobjarrayklass(); 150 } 151 return CURRENT_THREAD_ENV->get_obj_array_klass(array); 152 } 153 154 // The array klass was unable to be made or the element klass was not loaded. 155 ciSymbol* array_name = construct_array_name(element_klass->name(), 1); 156 if (array_name == ciEnv::unloaded_cisymbol()) { 157 return ciEnv::unloaded_ciobjarrayklass(); 158 } 159 return 160 CURRENT_ENV->get_unloaded_klass(element_klass, array_name) 161 ->as_obj_array_klass(); 162 } 163 164 // ------------------------------------------------------------------ 165 // ciObjArrayKlass::make 166 // 167 // Make an array klass corresponding to the specified primitive type. 168 ciObjArrayKlass* ciObjArrayKlass::make(ciKlass* element_klass) { 169 GUARDED_VM_ENTRY(return make_impl(element_klass);) 170 } 171 172 ciObjArrayKlass* ciObjArrayKlass::make(ciKlass* element_klass, int dims) { 173 ciKlass* klass = element_klass; 174 for (int i = 0; i < dims; i++) { 175 klass = ciObjArrayKlass::make(klass); 176 } 177 return klass->as_obj_array_klass(); 178 } 179 180 ciKlass* ciObjArrayKlass::exact_klass() { 181 // Even if MyValue is exact, [LMyValue is not exact due to [QMyValue <: [LMyValue. 182 if (!is_elem_null_free() && (!is_loaded() || element_klass()->is_inlinetype())) { 183 return NULL; 184 } 185 ciType* base = base_element_type(); 186 if (base->is_instance_klass()) { 187 ciInstanceKlass* ik = base->as_instance_klass(); 188 if (ik->exact_klass() != NULL) { 189 return this; 190 } 191 } else if (base->is_primitive_type()) { 192 return this; 193 } 194 return NULL; 195 }