1e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman//==- llvm/Support/Recycler.h - Recycling Allocator --------------*- C++ -*-==// 2e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman// 3e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman// The LLVM Compiler Infrastructure 4e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman// 5e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman// This file is distributed under the University of Illinois Open Source 6e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman// License. See LICENSE.TXT for details. 7e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman// 8e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman//===----------------------------------------------------------------------===// 9e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman// 10e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman// This file defines the Recycler class template. See the doxygen comment for 11e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman// Recycler for more details. 12e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman// 13e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman//===----------------------------------------------------------------------===// 14e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman 15e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman#ifndef LLVM_SUPPORT_RECYCLER_H 16e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman#define LLVM_SUPPORT_RECYCLER_H 17e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman 18fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman#include "llvm/ADT/ilist.h" 19fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman#include "llvm/Support/AlignOf.h" 2036b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines#include "llvm/Support/Allocator.h" 2150bee42b54cd9aec5f49566307df2b0cf23afcf6Craig Topper#include "llvm/Support/ErrorHandling.h" 22fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman#include <cassert> 23e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman 24e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohmannamespace llvm { 25e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman 26e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman/// PrintRecyclingAllocatorStats - Helper for RecyclingAllocator for 27e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman/// printing statistics. 28e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman/// 29fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohmanvoid PrintRecyclerStats(size_t Size, size_t Align, size_t FreeListSize); 30fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman 31fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman/// RecyclerStruct - Implementation detail for Recycler. This is a 32fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman/// class that the recycler imposes on free'd memory to carve out 33fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman/// next/prev pointers. 34fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohmanstruct RecyclerStruct { 35fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman RecyclerStruct *Prev, *Next; 36fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman}; 37fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman 38fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohmantemplate<> 3959bf4fcc0680e75b408579064d1205a132361196Duncan Sandsstruct ilist_traits<RecyclerStruct> : 4059bf4fcc0680e75b408579064d1205a132361196Duncan Sands public ilist_default_traits<RecyclerStruct> { 41fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman static RecyclerStruct *getPrev(const RecyclerStruct *t) { return t->Prev; } 42fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman static RecyclerStruct *getNext(const RecyclerStruct *t) { return t->Next; } 43fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman static void setPrev(RecyclerStruct *t, RecyclerStruct *p) { t->Prev = p; } 44fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman static void setNext(RecyclerStruct *t, RecyclerStruct *n) { t->Next = n; } 45fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman 46fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman mutable RecyclerStruct Sentinel; 47fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman RecyclerStruct *createSentinel() const { 48fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman return &Sentinel; 49fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman } 50fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman static void destroySentinel(RecyclerStruct *) {} 51fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman 52c23b8719ef9d6b1220e854b37d40e9e1c48a82bcGabor Greif RecyclerStruct *provideInitialHead() const { return createSentinel(); } 53c23b8719ef9d6b1220e854b37d40e9e1c48a82bcGabor Greif RecyclerStruct *ensureHead(RecyclerStruct*) const { return createSentinel(); } 54f3841fcbd587c31aa9842b3f33bd57de40c9f443Gabor Greif static void noteHead(RecyclerStruct*, RecyclerStruct*) {} 55c23b8719ef9d6b1220e854b37d40e9e1c48a82bcGabor Greif 56fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman static void deleteNode(RecyclerStruct *) { 5750bee42b54cd9aec5f49566307df2b0cf23afcf6Craig Topper llvm_unreachable("Recycler's ilist_traits shouldn't see a deleteNode call!"); 58fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman } 59fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman}; 60e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman 61e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman/// Recycler - This class manages a linked-list of deallocated nodes 62e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman/// and facilitates reusing deallocated memory in place of allocating 63fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman/// new memory. 64e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman/// 65fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohmantemplate<class T, size_t Size = sizeof(T), size_t Align = AlignOf<T>::Alignment> 66e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohmanclass Recycler { 67e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman /// FreeList - Doubly-linked list of nodes that have deleted contents and 68e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman /// are not in active use. 69e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman /// 70fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman iplist<RecyclerStruct> FreeList; 71e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman 72e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohmanpublic: 73fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman ~Recycler() { 74fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman // If this fails, either the callee has lost track of some allocation, 75fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman // or the callee isn't tracking allocations and should just call 76fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman // clear() before deleting the Recycler. 77fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman assert(FreeList.empty() && "Non-empty recycler deleted!"); 78fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman } 79e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman 80fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman /// clear - Release all the tracked allocations to the allocator. The 81fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman /// recycler must be free of any tracked allocations before being 82fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman /// deleted; calling clear is one way to ensure this. 83e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman template<class AllocatorType> 84e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman void clear(AllocatorType &Allocator) { 85fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman while (!FreeList.empty()) { 86fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman T *t = reinterpret_cast<T *>(FreeList.remove(FreeList.begin())); 87fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman Allocator.Deallocate(t); 88fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman } 89e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman } 90e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman 91b2e01b3707e23276a087f0f67edfc86082acdaa2Jakob Stoklund Olesen /// Special case for BumpPtrAllocator which has an empty Deallocate() 92b2e01b3707e23276a087f0f67edfc86082acdaa2Jakob Stoklund Olesen /// function. 93b2e01b3707e23276a087f0f67edfc86082acdaa2Jakob Stoklund Olesen /// 94b2e01b3707e23276a087f0f67edfc86082acdaa2Jakob Stoklund Olesen /// There is no need to traverse the free list, pulling all the objects into 95b2e01b3707e23276a087f0f67edfc86082acdaa2Jakob Stoklund Olesen /// cache. 96b2e01b3707e23276a087f0f67edfc86082acdaa2Jakob Stoklund Olesen void clear(BumpPtrAllocator&) { 97b2e01b3707e23276a087f0f67edfc86082acdaa2Jakob Stoklund Olesen FreeList.clearAndLeakNodesUnsafely(); 98b2e01b3707e23276a087f0f67edfc86082acdaa2Jakob Stoklund Olesen } 99b2e01b3707e23276a087f0f67edfc86082acdaa2Jakob Stoklund Olesen 100e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman template<class SubClass, class AllocatorType> 101e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman SubClass *Allocate(AllocatorType &Allocator) { 10236b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines static_assert(AlignOf<SubClass>::Alignment <= Align, 10336b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines "Recycler allocation alignment is less than object align!"); 10436b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines static_assert(sizeof(SubClass) <= Size, 10536b56886974eae4f9c5ebc96befd3e7bfe5de338Stephen Hines "Recycler allocation size is less than object size!"); 106fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman return !FreeList.empty() ? 107fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman reinterpret_cast<SubClass *>(FreeList.remove(FreeList.begin())) : 108fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman static_cast<SubClass *>(Allocator.Allocate(Size, Align)); 109e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman } 110e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman 111e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman template<class AllocatorType> 112e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman T *Allocate(AllocatorType &Allocator) { 113e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman return Allocate<T>(Allocator); 114e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman } 115e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman 116e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman template<class SubClass, class AllocatorType> 11798fd7f6b2f109e16abf3e4279c971f8d3703b8a6Bill Wendling void Deallocate(AllocatorType & /*Allocator*/, SubClass* Element) { 118fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman FreeList.push_front(reinterpret_cast<RecyclerStruct *>(Element)); 119e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman } 120e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman 121e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman void PrintStats() { 122fed90b6d097d50881afb45e4d79f430db66dd741Dan Gohman PrintRecyclerStats(Size, Align, FreeList.size()); 123e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman } 124e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman}; 125e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman 126e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman} 127e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman 128e14d81deeb6bb3404ffee5e59ecb88304f112f4aDan Gohman#endif 129