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 <ostream>
  44
  45 /** uint64_t constant */
  46 #define ULL(N)          ((uint64_t)N##ULL)
  47 /** int64_t constant */
  48 #define LL(N)           ((int64_t)N##LL)
  49
  50 /** Statistics counter type.  Not much excuse for not using a 64-bit
  51  * integer here, but if you're desperate and only run short
  52  * simulations you could make this 32 bits.
  53  */
  54 typedef int64_t Counter;
  55
  56 /**
  57  * Tick count type.
  58  */
  59 typedef uint64_t Tick;
  60
  61 const Tick MaxTick = ULL(0xffffffffffffffff);
  62
  63 /**
  64  * Cycles is a wrapper class for representing cycle counts, i.e. a
  65  * relative difference between two points in time, expressed in a
  66  * number of clock cycles.
  67  *
  68  * The Cycles wrapper class is a type-safe alternative to a
  69  * typedef, aiming to avoid unintentional mixing of cycles and ticks
  70  * in the code base.
  71  *
  72  * Operators are defined inside an ifndef block to avoid swig touching
  73  * them. Note that there is no overloading of the bool operator as the
  74  * compiler is allowed to turn booleans into integers and this causes
  75  * a whole range of issues in a handful locations. The solution to
  76  * this problem would be to use the safe bool idiom, but for now we
  77  * make do without the test and use the more elaborate comparison >
  78  * Cycles(0).
  79  */
  80 class Cycles
  81 {
  82
  83   private:
  84
  85     /** Member holding the actual value. */
  86     uint64_t c;
  87
  88   public:
  89
  90     /** Explicit constructor assigning a value. */
  91     explicit Cycles(uint64_t _c) : c(_c) { }
  92
  93     /** Default constructor for parameter classes. */
  94     Cycles() : c(0) { }
  95
  96 #ifndef SWIG // keep the operators away from SWIG
  97
  98     /** Converting back to the value type. */
  99     operator uint64_t() const { return c; }
 100
 101     /** Prefix increment operator. */
 102     Cycles& operator++()
 103     { ++c; return *this; }
 104
 105     /** Prefix decrement operator. Is only temporarily used in the O3 CPU. */
 106     Cycles& operator--()
 107     { assert(c != 0); --c; return *this; }
 108
 109     /** In-place addition of cycles. */
 110     const Cycles& operator+=(const Cycles& cc)
 111     { c += cc.c; return *this; }
 112
 113     /** Greater than comparison used for > Cycles(0). */
 114     bool operator>(const Cycles& cc) const
 115     { return c > cc.c; }
 116
 117     const Cycles operator +(const Cycles& b) const
 118     { return Cycles(c + b.c); }
 119
 120     const Cycles operator -(const Cycles& b) const
 121     { assert(c >= b.c); return Cycles(c - b.c); }
 122
 123     const Cycles operator <<(const int32_t shift)
 124     { return Cycles(c << shift); }
 125
 126     const Cycles operator >>(const int32_t shift)
 127     { return Cycles(c >> shift); }
 128
 129     friend std::ostream& operator<<(std::ostream &out, const Cycles & cycles);
 130
 131 #endif // SWIG not touching operators
 132
 133 };
 134
 135 /**
 136  * Address type
 137  * This will probably be moved somewhere else in the near future.
 138  * This should be at least as big as the biggest address width in use
 139  * in the system, which will probably be 64 bits.
 140  */
 141 typedef uint64_t Addr;
 142
 143 typedef uint16_t MicroPC;
 144
 145 static const MicroPC MicroPCRomBit = 1 << (sizeof(MicroPC) * 8 - 1);
 146
 147 static inline MicroPC
 148 romMicroPC(MicroPC upc)
 149 {
 150     return upc | MicroPCRomBit;
 151 }
 152
 153 static inline MicroPC
 154 normalMicroPC(MicroPC upc)
 155 {
 156     return upc & ~MicroPCRomBit;
 157 }
 158
 159 static inline bool
 160 isRomMicroPC(MicroPC upc)
 161 {
 162     return MicroPCRomBit & upc;
 163 }
 164
 165 const Addr MaxAddr = (Addr)-1;
 166
 167 /**
 168  * Thread index/ID type
 169  */
 170 typedef int16_t ThreadID;
 171 const ThreadID InvalidThreadID = (ThreadID)-1;
 172
 173 /**
 174  * Port index/ID type, and a symbolic name for an invalid port id.
 175  */
 176 typedef int16_t PortID;
 177 const PortID InvalidPortID = (PortID)-1;
 178
 179 class FaultBase;
 180 template <class T> class RefCountingPtr;
 181 typedef RefCountingPtr<FaultBase> Fault;
 182
 183 #endif // __BASE_TYPES_HH__