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28// Copyright (c) 2001-2004 NovodeX AG. All rights reserved.
29
30
31#ifndef PXC_THREADCOHERENTCACHE_H
32#define PXC_THREADCOHERENTCACHE_H
33
34#include "PsMutex.h"
35#include "PsAllocator.h"
36#include "PsSList.h"
37
38namespace physx
39{
40
41class PxsContext;
42/*!
43Controls a pool of large objects which must be thread safe.
44Tries to return the object most recently used by the thread(for better cache coherancy).
45Assumes the object has a default contructor.
46
47(Note the semantics are different to a pool because we dont want to construct/destroy each time
48an object is requested, which may be expensive).
49
50TODO: add thread coherancy.
51*/
52template<class T, class Params>
53class PxcThreadCoherentCache : public Ps::AlignedAllocator<16, Ps::ReflectionAllocator<T> >
54{
55 typedef Ps::AlignedAllocator<16, Ps::ReflectionAllocator<T> > Allocator;
56 PX_NOCOPY(PxcThreadCoherentCache)
57public:
58
59 typedef Ps::SListEntry EntryBase;
60
61 PX_INLINE PxcThreadCoherentCache(Params* params, const Allocator& alloc = Allocator()) : Allocator(alloc), mParams(params)
62 {
63 }
64
65 PX_INLINE ~PxcThreadCoherentCache()
66 {
67 T* np = static_cast<T*>(root.pop());
68
69 while(np!=NULL)
70 {
71 np->~T();
72 Allocator::deallocate(np);
73 np = static_cast<T*>(root.pop());
74 }
75 }
76
77 PX_INLINE T* get()
78 {
79 T* rv = static_cast<T*>(root.pop());
80 if(rv==NULL)
81 {
82 rv = reinterpret_cast<T*>(Allocator::allocate(sizeof(T), __FILE__, __LINE__));
83 new (rv) T(mParams);
84 }
85
86 return rv;
87 }
88
89 PX_INLINE void put(T* item)
90 {
91 root.push(entry&: *item);
92 }
93
94
95private:
96 Ps::SList root;
97 Params* mParams;
98
99 template<class T2, class P2>
100 friend class PxcThreadCoherentCacheIterator;
101};
102
103/*!
104Used to iterate over all objects controlled by the cache.
105
106Note: The iterator flushes the cache(extracts all items on construction and adds them back on
107destruction so we can iterate the list in a safe manner).
108*/
109template<class T, class Params>
110class PxcThreadCoherentCacheIterator
111{
112public:
113 PxcThreadCoherentCacheIterator(PxcThreadCoherentCache<T, Params>& cache) : mCache(cache)
114 {
115 mNext = cache.root.flush();
116 mFirst = mNext;
117 }
118 ~PxcThreadCoherentCacheIterator()
119 {
120 Ps::SListEntry* np = mFirst;
121 while(np != NULL)
122 {
123 Ps::SListEntry* npNext = np->next();
124 mCache.root.push(*np);
125 np = npNext;
126 }
127 }
128
129 PX_INLINE T* getNext()
130 {
131 if(mNext == NULL)
132 return NULL;
133
134 T* rv = static_cast<T*>(mNext);
135 mNext = mNext->next();
136
137 return rv;
138 }
139private:
140
141 PxcThreadCoherentCacheIterator<T, Params>& operator=(const PxcThreadCoherentCacheIterator<T, Params>&);
142 PxcThreadCoherentCache<T, Params> &mCache;
143 Ps::SListEntry* mNext;
144 Ps::SListEntry* mFirst;
145
146};
147
148}
149
150#endif
151

source code of qtquick3dphysics/src/3rdparty/PhysX/source/lowlevel/common/include/utils/PxcThreadCoherentCache.h