Files
gem5/src/mem/ruby/common/Set.hh
Andreas Hansson 2698e73966 base: Use the global Mersenne twister throughout
This patch tidies up random number generation to ensure that it is
done consistently throughout the code base. In essence this involves a
clean-up of Ruby, and some code simplifications in the traffic
generator.

As part of this patch a bunch of skewed distributions (off-by-one etc)
have been fixed.

Note that a single global random number generator is used, and that
the object instantiation order will impact the behaviour (the sequence
of numbers will be unaffected, but if module A calles random before
module B then they would obviously see a different outcome). The
dependency on the instantiation order is true in any case due to the
execution-model of gem5, so we leave it as is. Also note that the
global ranom generator is not thread safe at this point.

Regressions using the memtest, TrafficGen or any Ruby tester are
affected and will be updated accordingly.
2014-09-03 07:42:54 -04:00

167 lines
4.9 KiB
C++

/*
* Copyright (c) 1999-2008 Mark D. Hill and David A. Wood
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
// modified by Dan Gibson on 05/20/05 to accomidate FASTER
// >32 set lengths, using an array of ints w/ 32 bits/int
#ifndef __MEM_RUBY_COMMON_SET_HH__
#define __MEM_RUBY_COMMON_SET_HH__
#include <iostream>
#include <limits>
#include "mem/ruby/common/TypeDefines.hh"
/*
* This defines the number of longs (32-bits on 32 bit machines,
* 64-bit on 64-bit AMD machines) to use to hold the set...
* the default is 4, allowing 128 or 256 different members
* of the set.
*
* This should never need to be changed for correctness reasons,
* though increasing it will increase performance for larger
* set sizes at the cost of a (much) larger memory footprint
*
*/
const int NUMBER_WORDS_PER_SET = 1;
class Set
{
private:
int m_nSize; // the number of bits in this set
int m_nArrayLen; // the number of 32-bit words that are
// held in the array
// Changed 5/24/05 for static allocation of array
// note that "long" corresponds to 32 bits on a 32-bit machine,
// 64 bits if the -m64 parameter is passed to g++, which it is
// for an AMD opteron under our configuration
long *m_p_nArray; // an word array to hold the bits in the set
long m_p_nArray_Static[NUMBER_WORDS_PER_SET];
static const int LONG_BITS = std::numeric_limits<long>::digits + 1;
static const int INDEX_SHIFT = LONG_BITS == 64 ? 6 : 5;
static const int INDEX_MASK = (1 << INDEX_SHIFT) - 1;
void clearExcess();
public:
Set();
Set(int size);
Set(const Set& obj);
~Set();
Set& operator=(const Set& obj);
void
add(NodeID index)
{
m_p_nArray[index >> INDEX_SHIFT] |=
(((unsigned long) 1) << (index & INDEX_MASK));
}
void addSet(const Set& set);
void
remove(NodeID index)
{
m_p_nArray[index >> INDEX_SHIFT] &=
~(((unsigned long)1) << (index & INDEX_MASK));
}
void removeSet(const Set& set);
void
clear()
{
for (int i = 0; i < m_nArrayLen; i++)
m_p_nArray[i] = 0;
}
void broadcast();
int count() const;
bool isEqual(const Set& set) const;
// return the logical OR of this set and orSet
Set OR(const Set& orSet) const;
// return the logical AND of this set and andSet
Set AND(const Set& andSet) const;
// Returns true if the intersection of the two sets is empty
bool
intersectionIsEmpty(const Set& other_set) const
{
for (int i = 0; i < m_nArrayLen; i++)
if (m_p_nArray[i] & other_set.m_p_nArray[i])
return false;
return true;
}
bool isSuperset(const Set& test) const;
bool isSubset(const Set& test) const { return test.isSuperset(*this); }
bool
isElement(NodeID element) const
{
return (m_p_nArray[element>>INDEX_SHIFT] &
(((unsigned long)1) << (element & INDEX_MASK))) != 0;
}
bool isBroadcast() const;
bool isEmpty() const;
NodeID smallestElement() const;
void setSize(int size);
NodeID
elementAt(int index) const
{
if (isElement(index))
return (NodeID)true;
else
return 0;
}
int getSize() const { return m_nSize; }
void print(std::ostream& out) const;
};
inline std::ostream&
operator<<(std::ostream& out, const Set& obj)
{
obj.print(out);
out << std::flush;
return out;
}
#endif // __MEM_RUBY_COMMON_SET_HH__