types.hh revision 11990:5fad911cc326 
1/*
2 * Copyright (c) 2003-2005 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/**
32 * @file
33 * Defines global host-dependent types:
34 * Counter, Tick, and (indirectly) {int,uint}{8,16,32,64}_t.
35 */
36
37#ifndef __BASE_TYPES_HH__
38#define __BASE_TYPES_HH__
39
40#include <inttypes.h>
41
42#include <cassert>
43#include <memory>
44#include <ostream>
45#include <stdexcept>
46
47#include "base/refcnt.hh"
48
49/** uint64_t constant */
50#define ULL(N)          ((uint64_t)N##ULL)
51/** int64_t constant */
52#define LL(N)           ((int64_t)N##LL)
53
54/** Statistics counter type.  Not much excuse for not using a 64-bit
55 * integer here, but if you're desperate and only run short
56 * simulations you could make this 32 bits.
57 */
58typedef int64_t Counter;
59
60/**
61 * Tick count type.
62 */
63typedef uint64_t Tick;
64
65const Tick MaxTick = ULL(0xffffffffffffffff);
66
67/**
68 * Cycles is a wrapper class for representing cycle counts, i.e. a
69 * relative difference between two points in time, expressed in a
70 * number of clock cycles.
71 *
72 * The Cycles wrapper class is a type-safe alternative to a
73 * typedef, aiming to avoid unintentional mixing of cycles and ticks
74 * in the code base.
75 *
76 * Note that there is no overloading of the bool operator as the
77 * compiler is allowed to turn booleans into integers and this causes
78 * a whole range of issues in a handful locations. The solution to
79 * this problem would be to use the safe bool idiom, but for now we
80 * make do without the test and use the more elaborate comparison >
81 * Cycles(0).
82 */
83class Cycles
84{
85
86  private:
87
88    /** Member holding the actual value. */
89    uint64_t c;
90
91  public:
92
93    /** Explicit constructor assigning a value. */
94    explicit constexpr Cycles(uint64_t _c) : c(_c) { }
95
96    /** Default constructor for parameter classes. */
97    Cycles() : c(0) { }
98
99    /** Converting back to the value type. */
100    constexpr operator uint64_t() const { return c; }
101
102    /** Prefix increment operator. */
103    Cycles& operator++()
104    { ++c; return *this; }
105
106    /** Prefix decrement operator. Is only temporarily used in the O3 CPU. */
107    Cycles& operator--()
108    { assert(c != 0); --c; return *this; }
109
110    /** In-place addition of cycles. */
111    Cycles& operator+=(const Cycles& cc)
112    { c += cc.c; return *this; }
113
114    /** Greater than comparison used for > Cycles(0). */
115    constexpr bool operator>(const Cycles& cc) const
116    { return c > cc.c; }
117
118    constexpr Cycles operator +(const Cycles& b) const
119    { return Cycles(c + b.c); }
120
121    constexpr Cycles operator -(const Cycles& b) const
122    {
123        return c >= b.c ? Cycles(c - b.c) :
124            throw std::invalid_argument("RHS cycle value larger than LHS");
125    }
126
127    constexpr Cycles operator <<(const int32_t shift) const
128    { return Cycles(c << shift); }
129
130    constexpr Cycles operator >>(const int32_t shift) const
131    { return Cycles(c >> shift); }
132
133    friend std::ostream& operator<<(std::ostream &out, const Cycles & cycles);
134};
135
136/**
137 * Address type
138 * This will probably be moved somewhere else in the near future.
139 * This should be at least as big as the biggest address width in use
140 * in the system, which will probably be 64 bits.
141 */
142typedef uint64_t Addr;
143
144typedef uint16_t MicroPC;
145
146static const MicroPC MicroPCRomBit = 1 << (sizeof(MicroPC) * 8 - 1);
147
148static inline MicroPC
149romMicroPC(MicroPC upc)
150{
151    return upc | MicroPCRomBit;
152}
153
154static inline MicroPC
155normalMicroPC(MicroPC upc)
156{
157    return upc & ~MicroPCRomBit;
158}
159
160static inline bool
161isRomMicroPC(MicroPC upc)
162{
163    return MicroPCRomBit & upc;
164}
165
166const Addr MaxAddr = (Addr)-1;
167
168/**
169 * Thread index/ID type
170 */
171typedef int16_t ThreadID;
172const ThreadID InvalidThreadID = (ThreadID)-1;
173
174/** Globally unique thread context ID */
175typedef int ContextID;
176const ContextID InvalidContextID = (ContextID)-1;
177
178/**
179 * Port index/ID type, and a symbolic name for an invalid port id.
180 */
181typedef int16_t PortID;
182const PortID InvalidPortID = (PortID)-1;
183
184class FaultBase;
185typedef std::shared_ptr<FaultBase> Fault;
186
187// Rather than creating a shared_ptr instance and assigning it nullptr,
188// we just create an alias.
189constexpr decltype(nullptr) NoFault = nullptr;
190
191struct AtomicOpFunctor
192{
193    virtual void operator()(uint8_t *p) = 0;
194    virtual ~AtomicOpFunctor() {}
195};
196
197template <class T>
198struct TypedAtomicOpFunctor : public AtomicOpFunctor
199{
200    void operator()(uint8_t *p) { execute((T *)p); }
201    virtual void execute(T * p) = 0;
202};
203
204enum ByteOrder {
205    BigEndianByteOrder,
206    LittleEndianByteOrder
207};
208
209#endif // __BASE_TYPES_HH__
210