gem5/base/fast_alloc.cc
Steve Reinhardt e537fb3fd6 Add #define parameter and corresponding build option to
disable FastAlloc.  Gcc 3.3.x appears to have a bug that
breaks FastAlloc when compiled with optimization.

base/fast_alloc.cc:
base/fast_alloc.hh:
    #define NO_FAST_ALLOC makes FastAlloc a no-op.

--HG--
extra : convert_revision : bf4bb8e963331c6782f2cfd475a811aa520e31b5
2003-12-15 20:55:10 -08:00

195 lines
5 KiB
C++

/*
* Copyright (c) 2003 The Regents of The University of Michigan
* 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.
*/
/*
* This code was originally written by Steve Reinhardt as part of
* the Wisconsin Wind Tunnel simulator. Relicensed as part of M5
* by permission.
*/
#ifndef NO_FAST_ALLOC
#ifdef __GNUC__
#pragma implementation
#endif
#include <assert.h>
#include "base/fast_alloc.hh"
void *FastAlloc::freeLists[Num_Buckets];
#ifdef FAST_ALLOC_STATS
unsigned FastAlloc::newCount[Num_Buckets];
unsigned FastAlloc::deleteCount[Num_Buckets];
unsigned FastAlloc::allocCount[Num_Buckets];
#endif
void *FastAlloc::moreStructs(int bucket)
{
assert(bucket > 0 && bucket < Num_Buckets);
int sz = bucket * Alloc_Quantum;
const int nstructs = Num_Structs_Per_New; // how many to allocate?
char *p = ::new char[nstructs * sz];
#ifdef FAST_ALLOC_STATS
++allocCount[bucket];
#endif
freeLists[bucket] = p;
for (int i = 0; i < (nstructs-2); ++i, p += sz)
*(void **)p = p + sz;
*(void **)p = 0;
return (p + sz);
}
#ifdef FAST_ALLOC_DEBUG
#include <typeinfo>
#include <iostream>
#include <iomanip>
#include <map>
#include <string>
using namespace std;
// count of in-use FastAlloc objects
int FastAlloc::numInUse;
// dummy head & tail object for doubly linked list of in-use FastAlloc
// objects
FastAlloc FastAlloc::inUseHead(&FastAlloc::inUseHead, &FastAlloc::inUseHead);
// special constructor for dummy head: make inUsePrev & inUseNext
// point to self
FastAlloc::FastAlloc(FastAlloc *prev, FastAlloc *next)
{
inUsePrev = prev;
inUseNext = next;
}
// constructor: marks as in use, add to in-use list
FastAlloc::FastAlloc()
{
// mark this object in use
inUse = true;
// update count
++numInUse;
// add to tail of list of in-use objects ("before" dummy head)
FastAlloc *myNext = &inUseHead;
FastAlloc *myPrev = inUseHead.inUsePrev;
inUsePrev = myPrev;
inUseNext = myNext;
myPrev->inUseNext = this;
myNext->inUsePrev = this;
}
// destructor: mark not in use, remove from in-use list
FastAlloc::~FastAlloc()
{
assert(inUse);
inUse = false;
--numInUse;
assert(numInUse >= 0);
// remove me from in-use list
inUsePrev->inUseNext = inUseNext;
inUseNext->inUsePrev = inUsePrev;
}
// summarize in-use list
void
FastAlloc::dump_summary()
{
map<string, int> typemap;
for (FastAlloc *p = inUseHead.inUseNext; p != &inUseHead; p = p->inUseNext)
{
++typemap[typeid(*p).name()];
}
map<string, int>::const_iterator mapiter;
cout << " count type\n"
<< " ----- ----\n";
for (mapiter = typemap.begin(); mapiter != typemap.end(); ++mapiter)
{
cout << setw(6) << mapiter->second << " " << mapiter->first << endl;
}
}
// show oldest n items on in-use list
void
FastAlloc::dump_oldest(int n)
{
// sanity check: don't want to crash the debugger if you forget to
// pass in a parameter
if (n < 0 || n > numInUse)
{
cout << "FastAlloc::dump_oldest: bad arg " << n
<< " (" << numInUse << " objects in use" << endl;
return;
}
for (FastAlloc *p = inUseHead.inUsePrev;
p != &inUseHead && n > 0;
p = p->inUsePrev, --n)
{
cout << p << " " << typeid(*p).name() << endl;
}
}
//
// C interfaces to FastAlloc::dump_summary() and FastAlloc::dump_oldest().
// gdb seems to have trouble with calling C++ functions directly.
//
extern "C" void
fast_alloc_summary()
{
FastAlloc::dump_summary();
}
extern "C" void
fast_alloc_oldest(int n)
{
FastAlloc::dump_oldest(n);
}
#endif
#endif // NO_FAST_ALLOC