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Diffstat (limited to 'base/fast_alloc.hh')
| -rw-r--r-- | base/fast_alloc.hh | 214 |
1 files changed, 0 insertions, 214 deletions
diff --git a/base/fast_alloc.hh b/base/fast_alloc.hh deleted file mode 100644 index 54e35f8e0..000000000 --- a/base/fast_alloc.hh +++ /dev/null @@ -1,214 +0,0 @@ -/* - * Copyright (c) 2000-2001, 2003-2005 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 __FAST_ALLOC_H__ -#define __FAST_ALLOC_H__ - -#include <stddef.h> - -// Fast structure allocator. Designed for small objects that are -// frequently allocated and deallocated. This code is derived from the -// 'alloc_struct' package used in WWT and Blizzard. C++ provides a -// much nicer framework for the same optimization. The package is -// implemented as a class, FastAlloc. Allocation and deletion are -// performed using FastAlloc's new and delete operators. Any object -// that derives from the FastAlloc class will transparently use this -// allocation package. - -// The static allocate() and deallocate() methods can also be called -// directly if desired. - -// In order for derived classes to call delete with the correct -// structure size even when they are deallocated via a base-type -// pointer, they must have a virtual destructor. It is sufficient for -// FastAlloc to declare a virtual destructor (as it does); it is not -// required for derived classes to declare their own destructor. The -// compiler will automatically generate a virtual destructor for each -// derived class. However, it is more efficient if each derived class -// defines an inline destructor, so that the compiler can statically -// collapse the destructor call chain back up the inheritance -// hierarchy. - -// Uncomment this #define to track in-use objects -// (for debugging memory leaks). -//#define FAST_ALLOC_DEBUG - -// Uncomment this #define to count news, deletes, and chunk allocations -// (by bucket). -// #define FAST_ALLOC_STATS - -#include "config/no_fast_alloc.hh" - -#if NO_FAST_ALLOC - -class FastAlloc { -}; - -#else - -class FastAlloc { - public: - - static void *allocate(size_t); - static void deallocate(void *, size_t); - - void *operator new(size_t); - void operator delete(void *, size_t); - -#ifdef FAST_ALLOC_DEBUG - FastAlloc(); - FastAlloc(FastAlloc*,FastAlloc*); // for inUseHead, see below - virtual ~FastAlloc(); -#else - virtual ~FastAlloc() {} -#endif - - private: - - // Max_Alloc_Size is the largest object that can be allocated with - // this class. There's no fundamental limit, but this limits the - // size of the freeLists array. Let's not make this really huge - // like in Blizzard. - static const int Max_Alloc_Size = 512; - - // Alloc_Quantum is the difference in size between adjacent - // buckets in the free list array. - static const int Log2_Alloc_Quantum = 3; - static const int Alloc_Quantum = (1 << Log2_Alloc_Quantum); - - // Num_Buckets = bucketFor(Max_Alloc_Size) + 1 - static const int Num_Buckets = - ((Max_Alloc_Size + Alloc_Quantum - 1) >> Log2_Alloc_Quantum) + 1; - - // when we call new() for more structures, how many should we get? - static const int Num_Structs_Per_New = 20; - - static int bucketFor(size_t); - static void *moreStructs(int bucket); - - static void *freeLists[Num_Buckets]; - -#ifdef FAST_ALLOC_STATS - static unsigned newCount[Num_Buckets]; - static unsigned deleteCount[Num_Buckets]; - static unsigned allocCount[Num_Buckets]; -#endif - -#ifdef FAST_ALLOC_DEBUG - // per-object debugging fields - bool inUse; // in-use flag - FastAlloc *inUsePrev; // ptrs to build list of in-use objects - FastAlloc *inUseNext; - - // static (global) debugging vars - static int numInUse; // count in-use objects - static FastAlloc inUseHead; // dummy head for list of in-use objects - - public: - // functions to dump debugging info (see fast_alloc.cc for C - // versions that might be more agreeable to call from gdb) - static void dump_summary(); - static void dump_oldest(int n); -#endif -}; - - -inline -int FastAlloc::bucketFor(size_t sz) -{ - return (sz + Alloc_Quantum - 1) >> Log2_Alloc_Quantum; -} - - -inline -void *FastAlloc::allocate(size_t sz) -{ - int b; - void *p; - - if (sz > Max_Alloc_Size) - return (void *)::new char[sz]; - - b = bucketFor(sz); - p = freeLists[b]; - - if (p) - freeLists[b] = *(void **)p; - else - p = moreStructs(b); - -#ifdef FAST_ALLOC_STATS - ++newCount[b]; -#endif - - return p; -} - - -inline -void FastAlloc::deallocate(void *p, size_t sz) -{ - int b; - - if (sz > Max_Alloc_Size) - { - ::delete [] (char *)p; - return; - } - - b = bucketFor(sz); - *(void **)p = freeLists[b]; - freeLists[b] = p; -#ifdef FAST_ALLOC_STATS - ++deleteCount[b]; -#endif -} - - -inline -void *FastAlloc::operator new(size_t sz) -{ - return allocate(sz); -} - - -inline -void FastAlloc::operator delete(void *p, size_t sz) -{ - deallocate(p, sz); -} - -#endif // NO_FAST_ALLOC - -#endif // __FAST_ALLOC_H__ |