1/*
2 * Copyright (C) 2008-2019 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of Apple Inc. ("Apple") nor the names of
14 * its contributors may be used to endorse or promote products derived
15 * from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#pragma once
30
31#include "VirtualRegister.h"
32
33#include <wtf/Assertions.h>
34#include <wtf/VectorTraits.h>
35
36namespace JSC {
37
38 class RegisterID {
39 WTF_MAKE_NONCOPYABLE(RegisterID);
40
41 friend class VirtualRegister;
42 public:
43 RegisterID()
44 : m_refCount(0)
45 , m_isTemporary(false)
46#ifndef NDEBUG
47 , m_didSetIndex(false)
48#endif
49 {
50 }
51
52 RegisterID(VirtualRegister virtualRegister)
53 : m_refCount(0)
54 , m_virtualRegister(virtualRegister)
55 , m_isTemporary(false)
56#ifndef NDEBUG
57 , m_didSetIndex(true)
58#endif
59 {
60 }
61
62 explicit RegisterID(int index)
63 : m_refCount(0)
64 , m_virtualRegister(VirtualRegister(index))
65 , m_isTemporary(false)
66#ifndef NDEBUG
67 , m_didSetIndex(true)
68#endif
69 {
70 }
71
72 void setIndex(int index)
73 {
74#ifndef NDEBUG
75 m_didSetIndex = true;
76#endif
77 m_virtualRegister = VirtualRegister(index);
78 }
79
80 void setTemporary()
81 {
82 m_isTemporary = true;
83 }
84
85 int index() const
86 {
87 ASSERT(m_didSetIndex);
88 return m_virtualRegister.offset();
89 }
90
91 VirtualRegister virtualRegister() const
92 {
93 ASSERT(m_virtualRegister.isValid());
94 return m_virtualRegister;
95 }
96
97 bool isTemporary()
98 {
99 return m_isTemporary;
100 }
101
102 void ref()
103 {
104 ++m_refCount;
105 }
106
107 void deref()
108 {
109 --m_refCount;
110 ASSERT(m_refCount >= 0);
111 }
112
113 int refCount() const
114 {
115 return m_refCount;
116 }
117
118 private:
119
120 int m_refCount;
121 VirtualRegister m_virtualRegister;
122 bool m_isTemporary;
123#ifndef NDEBUG
124 bool m_didSetIndex;
125#endif
126 };
127} // namespace JSC
128
129namespace WTF {
130
131 template<> struct VectorTraits<JSC::RegisterID> : VectorTraitsBase<true, JSC::RegisterID> {
132 static constexpr bool needsInitialization = true;
133 static constexpr bool canInitializeWithMemset = true; // Default initialization just sets everything to 0 or false, so this is safe.
134 };
135
136} // namespace WTF
137