src/share/vm/ci/ciField.hpp

Wed, 03 Jul 2019 20:42:37 +0800

author
aoqi
date
Wed, 03 Jul 2019 20:42:37 +0800
changeset 9637
eef07cd490d4
parent 8856
ac27a9c85bea
permissions
-rw-r--r--

Merge

aoqi@0 1 /*
aoqi@0 2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0 4 *
aoqi@0 5 * This code is free software; you can redistribute it and/or modify it
aoqi@0 6 * under the terms of the GNU General Public License version 2 only, as
aoqi@0 7 * published by the Free Software Foundation.
aoqi@0 8 *
aoqi@0 9 * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
aoqi@0 12 * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0 13 * accompanied this code).
aoqi@0 14 *
aoqi@0 15 * You should have received a copy of the GNU General Public License version
aoqi@0 16 * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0 18 *
aoqi@0 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0 20 * or visit www.oracle.com if you need additional information or have any
aoqi@0 21 * questions.
aoqi@0 22 *
aoqi@0 23 */
aoqi@0 24
aoqi@0 25 #ifndef SHARE_VM_CI_CIFIELD_HPP
aoqi@0 26 #define SHARE_VM_CI_CIFIELD_HPP
aoqi@0 27
aoqi@0 28 #include "ci/ciClassList.hpp"
aoqi@0 29 #include "ci/ciConstant.hpp"
aoqi@0 30 #include "ci/ciFlags.hpp"
aoqi@0 31 #include "ci/ciInstance.hpp"
aoqi@0 32
aoqi@0 33 // ciField
aoqi@0 34 //
aoqi@0 35 // This class represents the result of a field lookup in the VM.
aoqi@0 36 // The lookup may not succeed, in which case the information in
aoqi@0 37 // the ciField will be incomplete.
aoqi@0 38 class ciField : public ResourceObj {
aoqi@0 39 CI_PACKAGE_ACCESS
aoqi@0 40 friend class ciEnv;
aoqi@0 41 friend class ciInstanceKlass;
aoqi@0 42 friend class NonStaticFieldFiller;
aoqi@0 43
aoqi@0 44 private:
aoqi@0 45 ciFlags _flags;
aoqi@0 46 ciInstanceKlass* _holder;
aoqi@0 47 ciSymbol* _name;
aoqi@0 48 ciSymbol* _signature;
aoqi@0 49 ciType* _type;
aoqi@0 50 int _offset;
aoqi@0 51 bool _is_constant;
aoqi@0 52 ciInstanceKlass* _known_to_link_with_put;
aoqi@0 53 ciInstanceKlass* _known_to_link_with_get;
aoqi@0 54 ciConstant _constant_value;
aoqi@0 55
aoqi@0 56 ciType* compute_type();
aoqi@0 57 ciType* compute_type_impl();
aoqi@0 58
aoqi@0 59 ciField(ciInstanceKlass* klass, int index);
aoqi@0 60 ciField(fieldDescriptor* fd);
aoqi@0 61
aoqi@0 62 // shared constructor code
aoqi@0 63 void initialize_from(fieldDescriptor* fd);
aoqi@0 64
aoqi@0 65 public:
aoqi@0 66 ciFlags flags() { return _flags; }
aoqi@0 67
aoqi@0 68 // Of which klass is this field a member?
aoqi@0 69 //
aoqi@0 70 // Usage note: the declared holder of a field is the class
aoqi@0 71 // referenced by name in the bytecodes. The canonical holder
aoqi@0 72 // is the most general class which holds the field. This
aoqi@0 73 // method returns the canonical holder. The declared holder
aoqi@0 74 // can be accessed via a method in ciBytecodeStream.
aoqi@0 75 //
aoqi@0 76 // Ex.
aoqi@0 77 // class A {
aoqi@0 78 // public int f = 7;
aoqi@0 79 // }
aoqi@0 80 // class B extends A {
aoqi@0 81 // public void test() {
aoqi@0 82 // System.out.println(f);
aoqi@0 83 // }
aoqi@0 84 // }
aoqi@0 85 //
aoqi@0 86 // A java compiler is permitted to compile the access to
aoqi@0 87 // field f as:
aoqi@0 88 //
aoqi@0 89 // getfield B.f
aoqi@0 90 //
aoqi@0 91 // In that case the declared holder of f would be B and
aoqi@0 92 // the canonical holder of f would be A.
aoqi@0 93 ciInstanceKlass* holder() { return _holder; }
aoqi@0 94
aoqi@0 95 // Name of this field?
aoqi@0 96 ciSymbol* name() { return _name; }
aoqi@0 97
aoqi@0 98 // Signature of this field?
aoqi@0 99 ciSymbol* signature() { return _signature; }
aoqi@0 100
aoqi@0 101 // Of what type is this field?
aoqi@0 102 ciType* type() { return (_type == NULL) ? compute_type() : _type; }
aoqi@0 103
aoqi@0 104 // How is this field actually stored in memory?
aoqi@0 105 BasicType layout_type() { return type2field[(_type == NULL) ? T_OBJECT : _type->basic_type()]; }
aoqi@0 106
aoqi@0 107 // How big is this field in memory?
aoqi@0 108 int size_in_bytes() { return type2aelembytes(layout_type()); }
aoqi@0 109
aoqi@0 110 // What is the offset of this field?
aoqi@0 111 int offset() {
aoqi@0 112 assert(_offset >= 1, "illegal call to offset()");
aoqi@0 113 return _offset;
aoqi@0 114 }
aoqi@0 115
aoqi@0 116 // Same question, explicit units. (Fields are aligned to the byte level.)
aoqi@0 117 int offset_in_bytes() {
aoqi@0 118 return offset();
aoqi@0 119 }
aoqi@0 120
aoqi@0 121 // Is this field shared?
aoqi@0 122 bool is_shared() {
aoqi@0 123 // non-static fields of shared holders are cached
aoqi@0 124 return _holder->is_shared() && !is_static();
aoqi@0 125 }
aoqi@0 126
zmajo@8664 127 // Is this field a constant? See ciField::initialize_from() for details
zmajo@8664 128 // about how a field is determined to be constant.
aoqi@0 129 bool is_constant() { return _is_constant; }
aoqi@0 130
aoqi@0 131 // Get the constant value of this field.
aoqi@0 132 ciConstant constant_value() {
aoqi@0 133 assert(is_static() && is_constant(), "illegal call to constant_value()");
aoqi@0 134 return _constant_value;
aoqi@0 135 }
aoqi@0 136
aoqi@0 137 // Get the constant value of non-static final field in the given
aoqi@0 138 // object.
aoqi@0 139 ciConstant constant_value_of(ciObject* object) {
aoqi@0 140 assert(!is_static() && is_constant(), "only if field is non-static constant");
aoqi@0 141 assert(object->is_instance(), "must be instance");
aoqi@0 142 return object->as_instance()->field_value(this);
aoqi@0 143 }
aoqi@0 144
aoqi@0 145 // Check for link time errors. Accessing a field from a
aoqi@0 146 // certain class via a certain bytecode may or may not be legal.
aoqi@0 147 // This call checks to see if an exception may be raised by
aoqi@0 148 // an access of this field.
aoqi@0 149 //
aoqi@0 150 // Usage note: if the same field is accessed multiple times
aoqi@0 151 // in the same compilation, will_link will need to be checked
aoqi@0 152 // at each point of access.
aoqi@0 153 bool will_link(ciInstanceKlass* accessing_klass,
aoqi@0 154 Bytecodes::Code bc);
aoqi@0 155
aoqi@0 156 // Java access flags
aoqi@0 157 bool is_public () { return flags().is_public(); }
aoqi@0 158 bool is_private () { return flags().is_private(); }
aoqi@0 159 bool is_protected () { return flags().is_protected(); }
aoqi@0 160 bool is_static () { return flags().is_static(); }
aoqi@0 161 bool is_final () { return flags().is_final(); }
aoqi@0 162 bool is_stable () { return flags().is_stable(); }
aoqi@0 163 bool is_volatile () { return flags().is_volatile(); }
aoqi@0 164 bool is_transient () { return flags().is_transient(); }
zmajo@8664 165 // The field is modified outside of instance initializer methods
zmajo@8664 166 // (or class/initializer methods if the field is static).
zmajo@8664 167 bool has_initialized_final_update() { return flags().has_initialized_final_update(); }
aoqi@0 168
aoqi@0 169 bool is_call_site_target() {
aoqi@0 170 ciInstanceKlass* callsite_klass = CURRENT_ENV->CallSite_klass();
aoqi@0 171 if (callsite_klass == NULL)
aoqi@0 172 return false;
aoqi@0 173 return (holder()->is_subclass_of(callsite_klass) && (name() == ciSymbol::target_name()));
aoqi@0 174 }
aoqi@0 175
aoqi@0 176 // Debugging output
aoqi@0 177 void print();
aoqi@0 178 void print_name_on(outputStream* st);
aoqi@0 179 };
aoqi@0 180
aoqi@0 181 #endif // SHARE_VM_CI_CIFIELD_HPP

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