src/base/types.hh

   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  */
  58 typedef int64_t Counter;
  59
  60 /**
  61  * Tick count type.
  62  */
  63 typedef uint64_t Tick;
  64
  65 const 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  * Operators are defined inside an ifndef block to avoid swig touching
  77  * them. Note that there is no overloading of the bool operator as the
  78  * compiler is allowed to turn booleans into integers and this causes
  79  * a whole range of issues in a handful locations. The solution to
  80  * this problem would be to use the safe bool idiom, but for now we
  81  * make do without the test and use the more elaborate comparison >
  82  * Cycles(0).
  83  */
  84 class Cycles
  85 {
  86
  87   private:
  88
  89     /** Member holding the actual value. */
  90     uint64_t c;
  91
  92   public:
  93
  94 #ifndef SWIG // SWIG gets confused by constexpr
  95     /** Explicit constructor assigning a value. */
  96     explicit constexpr Cycles(uint64_t _c) : c(_c) { }
  97 #else
  98     explicit Cycles(uint64_t _c) : c(_c) { }
  99 #endif
 100
 101     /** Default constructor for parameter classes. */
 102     Cycles() : c(0) { }
 103
 104 #ifndef SWIG // keep the operators away from SWIG
 105
 106     /** Converting back to the value type. */
 107     constexpr operator uint64_t() const { return c; }
 108
 109     /** Prefix increment operator. */
 110     Cycles& operator++()
 111     { ++c; return *this; }
 112
 113     /** Prefix decrement operator. Is only temporarily used in the O3 CPU. */
 114     Cycles& operator--()
 115     { assert(c != 0); --c; return *this; }
 116
 117     /** In-place addition of cycles. */
 118     Cycles& operator+=(const Cycles& cc)
 119     { c += cc.c; return *this; }
 120
 121     /** Greater than comparison used for > Cycles(0). */
 122     constexpr bool operator>(const Cycles& cc) const
 123     { return c > cc.c; }
 124
 125     constexpr Cycles operator +(const Cycles& b) const
 126     { return Cycles(c + b.c); }
 127
 128     constexpr Cycles operator -(const Cycles& b) const
 129     {
 130         return c >= b.c ? Cycles(c - b.c) :
 131             throw std::invalid_argument("RHS cycle value larger than LHS");
 132     }
 133
 134     constexpr Cycles operator <<(const int32_t shift) const
 135     { return Cycles(c << shift); }
 136
 137     constexpr Cycles operator >>(const int32_t shift) const
 138     { return Cycles(c >> shift); }
 139
 140     friend std::ostream& operator<<(std::ostream &out, const Cycles & cycles);
 141
 142 #endif // SWIG not touching operators
 143
 144 };
 145
 146 /**
 147  * Address type
 148  * This will probably be moved somewhere else in the near future.
 149  * This should be at least as big as the biggest address width in use
 150  * in the system, which will probably be 64 bits.
 151  */
 152 typedef uint64_t Addr;
 153
 154 typedef uint16_t MicroPC;
 155
 156 static const MicroPC MicroPCRomBit = 1 << (sizeof(MicroPC) * 8 - 1);
 157
 158 static inline MicroPC
 159 romMicroPC(MicroPC upc)
 160 {
 161     return upc | MicroPCRomBit;
 162 }
 163
 164 static inline MicroPC
 165 normalMicroPC(MicroPC upc)
 166 {
 167     return upc & ~MicroPCRomBit;
 168 }
 169
 170 static inline bool
 171 isRomMicroPC(MicroPC upc)
 172 {
 173     return MicroPCRomBit & upc;
 174 }
 175
 176 const Addr MaxAddr = (Addr)-1;
 177
 178 /**
 179  * Thread index/ID type
 180  */
 181 typedef int16_t ThreadID;
 182 const ThreadID InvalidThreadID = (ThreadID)-1;
 183
 184 /** Globally unique thread context ID */
 185 typedef int ContextID;
 186 const ContextID InvalidContextID = (ContextID)-1;
 187
 188 /**
 189  * Port index/ID type, and a symbolic name for an invalid port id.
 190  */
 191 typedef int16_t PortID;
 192 const PortID InvalidPortID = (PortID)-1;
 193
 194 class FaultBase;
 195 typedef std::shared_ptr<FaultBase> Fault;
 196
 197 #ifndef SWIG // Swig gets really confused by decltype
 198 // Rather than creating a shared_ptr instance and assigning it nullptr,
 199 // we just create an alias.
 200 constexpr decltype(nullptr) NoFault = nullptr;
 201 #endif
 202
 203 struct AtomicOpFunctor
 204 {
 205     virtual void operator()(uint8_t *p) = 0;
 206     virtual ~AtomicOpFunctor() {}
 207 };
 208
 209 template <class T>
 210 struct TypedAtomicOpFunctor : public AtomicOpFunctor
 211 {
 212     void operator()(uint8_t *p) { execute((T *)p); }
 213     virtual void execute(T * p) = 0;
 214 };
 215
 216 enum ByteOrder {
 217     BigEndianByteOrder,
 218     LittleEndianByteOrder
 219 };
 220
 221 #endif // __BASE_TYPES_HH__