vptr.hh revision 5191 
1/*
2 * Copyright (c) 2004-2005 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Nathan Binkert
29 */
30
31#ifndef __ARCH_ALPHA_VPTR_HH__
32#define __ARCH_ALPHA_VPTR_HH__
33
34#include "arch/vtophys.hh"
35#include "arch/isa_traits.hh"
36#include "mem/vport.hh"
37
38class ThreadContext;
39
40template <class T>
41class VPtr
42{
43  public:
44    typedef T Type;
45
46  protected:
47    ThreadContext *tc;
48    Addr ptr;
49    Addr buffer[(sizeof(T)-1)/sizeof(Addr) + 1];
50
51  public:
52    explicit VPtr(ThreadContext *_tc, Addr p = 0)
53        : tc(_tc), ptr(p)
54    {
55        refresh();
56    }
57
58    template <class U>
59    VPtr(const VPtr<U> &vp)
60        : tc(vp.tc), ptr(vp.ptr)
61    {
62        refresh();
63    }
64
65    ~VPtr()
66    {}
67
68    void
69    refresh()
70    {
71        if (!ptr)
72            return;
73
74        VirtualPort *port = tc->getVirtPort(tc);
75        port->readBlob(ptr, buffer, sizeof(T));
76        tc->delVirtPort(port);
77    }
78
79    bool
80    operator!() const
81    {
82        return ptr == 0;
83    }
84
85    VPtr<T>
86    operator+(int offset)
87    {
88        return VPtr<T>(tc, ptr + offset);
89    }
90
91    const VPtr<T> &
92    operator+=(int offset)
93    {
94        ptr += offset;
95        refresh();
96
97        return *this;
98    }
99
100    const VPtr<T> &
101    operator=(Addr p)
102    {
103        ptr = p;
104        refresh();
105
106        return *this;
107    }
108
109    template <class U>
110    const VPtr<T> &
111    operator=(const VPtr<U> &vp)
112    {
113        tc = vp.tc;
114        ptr = vp.ptr;
115        refresh();
116
117        return *this;
118    }
119
120    operator T *()
121    {
122        return (T *)buffer;
123    }
124
125    T *
126    operator->()
127    {
128        return (T *)buffer;
129    }
130
131    T &
132    operator*()
133    {
134        return *(T *)buffer;
135    }
136};
137
138#endif // __ARCH_ALPHA_VPTR_HH__
139