1/*
2 * Copyright (c) 2011, 2019, Oracle and/or its affiliates. All rights reserved.
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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7 * published by the Free Software Foundation.
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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).
14 *
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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23 */
24
25#ifndef SHARE_CI_CIBASEOBJECT_HPP
26#define SHARE_CI_CIBASEOBJECT_HPP
27
28#include "ci/ciClassList.hpp"
29#include "memory/allocation.hpp"
30#include "runtime/jniHandles.hpp"
31
32// ciBaseObject
33//
34// This class represents an oop in the HotSpot virtual machine.
35// Its subclasses are structured in a hierarchy which mirrors
36// an aggregate of the VM's oop and klass hierarchies (see
37// oopHierarchy.hpp). Each instance of ciBaseObject holds a handle
38// to a corresponding oop on the VM side and provides routines
39// for accessing the information in its oop. By using the ciBaseObject
40// hierarchy for accessing oops in the VM, the compiler ensures
41// that it is safe with respect to garbage collection; that is,
42// GC and compilation can proceed independently without
43// interference.
44//
45// Within the VM, the oop and klass hierarchies are separate.
46// The compiler interface does not preserve this separation --
47// the distinction between `Klass*' and `Klass' are not
48// reflected in the interface and instead the Klass hierarchy
49// is directly modeled as the subclasses of ciKlass.
50class ciBaseObject : public ResourceObj {
51 CI_PACKAGE_ACCESS
52 friend class ciEnv;
53
54protected:
55 uint _ident;
56
57protected:
58 ciBaseObject(): _ident(0) {}
59
60 virtual const char* type_string() { return "ciBaseObject"; }
61
62 void set_ident(uint id);
63
64public:
65 // A number unique to this object.
66 uint ident();
67
68 // What kind of ciBaseObject is this?
69 virtual bool is_symbol() const { return false; }
70 virtual bool is_object() const { return false; }
71 virtual bool is_metadata() const { return false; }
72
73 ciSymbol* as_symbol() {
74 assert(is_symbol(), "must be");
75 return (ciSymbol*)this;
76 }
77 ciObject* as_object() {
78 assert(is_object(), "must be");
79 return (ciObject*)this;
80 }
81 ciMetadata* as_metadata() {
82 assert(is_metadata(), "must be");
83 return (ciMetadata*)this;
84 }
85};
86#endif // SHARE_CI_CIBASEOBJECT_HPP
87