1 /* 2 * Copyright (c) 1999, 2024, 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 #ifndef SHARE_CI_CIKLASS_HPP 26 #define SHARE_CI_CIKLASS_HPP 27 28 #include "ci/ciType.hpp" 29 #include "oops/klass.hpp" 30 31 // ciKlass 32 // 33 // This class and its subclasses represent Klass*s in the 34 // HotSpot virtual machine. In the vm, each Klass* contains an 35 // embedded Klass object. ciKlass is subclassed to explicitly 36 // represent the kind of Klass embedded in the Klass*. For 37 // example, a Klass* with an embedded ObjArrayKlass object is 38 // represented in the ciObject hierarchy by the class 39 // ciObjArrayKlass. 40 class ciKlass : public ciType { 41 CI_PACKAGE_ACCESS 42 friend class ciEnv; 43 friend class ciField; 44 friend class ciMethod; 45 friend class ciMethodData; 46 friend class ciObjArrayKlass; 47 friend class ciReceiverTypeData; 48 friend class ciSignature; 49 friend class ciFlatArrayKlass; 50 friend class ciArrayKlass; 51 52 private: 53 ciSymbol* _name; 54 jint _layout_helper; 55 56 protected: 57 ciKlass(Klass* k, ciSymbol* name); 58 ciKlass(ciSymbol* name, BasicType bt); 59 60 Klass* get_Klass() const { 61 Klass* k = (Klass*)_metadata; 62 assert(k != nullptr, "illegal use of unloaded klass"); 63 return k; 64 } 65 66 // Certain subklasses have an associated class loader. 67 virtual oop loader() { return nullptr; } 68 virtual jobject loader_handle() { return nullptr; } 69 70 virtual oop protection_domain() { return nullptr; } 71 virtual jobject protection_domain_handle() { return nullptr; } 72 73 const char* type_string() { return "ciKlass"; } 74 75 void print_impl(outputStream* st); 76 77 public: 78 ciKlass(Klass* k); 79 80 // What is the name of this klass? 81 ciSymbol* name() const { return _name; } 82 83 // What is its layout helper value? 84 jint layout_helper() { return _layout_helper; } 85 86 bool is_subtype_of(ciKlass* klass); 87 bool is_subclass_of(ciKlass* klass); 88 juint super_depth(); 89 juint super_check_offset(); 90 ciKlass* super_of_depth(juint i); 91 static juint primary_super_limit() { return Klass::primary_super_limit(); } 92 93 // Is this ciObject the ciInstanceKlass representing java.lang.Object()? 94 virtual bool is_java_lang_Object() const { return false; } 95 96 // Get the shared parent of two klasses. 97 ciKlass* least_common_ancestor(ciKlass* k); 98 99 virtual bool is_interface() { 100 return false; 101 } 102 103 virtual bool is_abstract() { 104 return false; 105 } 106 107 // Does this type (array, class, interface) have no subtypes? 108 virtual bool is_leaf_type() { 109 return false; 110 } 111 112 virtual bool can_be_inline_klass(bool is_exact = false) { 113 return false; 114 } 115 116 virtual bool can_be_inline_array_klass() { 117 return EnableValhalla && is_java_lang_Object(); 118 } 119 120 // Attempt to get a klass using this ciKlass's loader. 121 ciKlass* find_klass(ciSymbol* klass_name); 122 // Note: To find a class from its name string, use ciSymbol::make, 123 // but consider adding to vmSymbols.hpp instead. 124 125 // Get the instance of java.lang.Class corresponding to this klass. 126 ciInstance* java_mirror(); 127 128 // Fetch Klass::modifier_flags. 129 jint modifier_flags(); 130 131 // Fetch Klass::access_flags. 132 jint access_flags(); 133 134 markWord prototype_header() const; 135 136 // Fetch Klass::misc_flags. 137 klass_flags_t misc_flags(); 138 139 // What kind of ciObject is this? 140 bool is_klass() const { return true; } 141 142 virtual ciKlass* exact_klass() = 0; 143 144 void print_name_on(outputStream* st); 145 146 const char* external_name() const; 147 }; 148 149 #endif // SHARE_CI_CIKLASS_HPP