1 /* libs/pixelflinger/codeflinger/CodeCache.h
2 **
3 ** Copyright 2006, The Android Open Source Project
4 **
5 ** Licensed under the Apache License, Version 2.0 (the "License");
6 ** you may not use this file except in compliance with the License.
7 ** You may obtain a copy of the License at
8 **
9 **     http://www.apache.org/licenses/LICENSE-2.0
10 **
11 ** Unless required by applicable law or agreed to in writing, software
12 ** distributed under the License is distributed on an "AS IS" BASIS,
13 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 ** See the License for the specific language governing permissions and
15 ** limitations under the License.
16 */
17 
18 
19 #ifndef ANDROID_CODECACHE_H
20 #define ANDROID_CODECACHE_H
21 
22 #include <stdint.h>
23 #include <pthread.h>
24 #include <sys/types.h>
25 
26 #include "tinyutils/KeyedVector.h"
27 #include "tinyutils/smartpointer.h"
28 
29 namespace android {
30 
31 using namespace tinyutils;
32 
33 // ----------------------------------------------------------------------------
34 
35 class AssemblyKeyBase {
36 public:
~AssemblyKeyBase()37     virtual ~AssemblyKeyBase() { }
38     virtual int compare_type(const AssemblyKeyBase& key) const = 0;
39 };
40 
41 template  <typename T>
42 class AssemblyKey : public AssemblyKeyBase
43 {
44 public:
AssemblyKey(const T & rhs)45     AssemblyKey(const T& rhs) : mKey(rhs) { }
compare_type(const AssemblyKeyBase & key)46     virtual int compare_type(const AssemblyKeyBase& key) const {
47         const T& rhs = static_cast<const AssemblyKey&>(key).mKey;
48         return android::compare_type(mKey, rhs);
49     }
50 private:
51     T mKey;
52 };
53 
54 // ----------------------------------------------------------------------------
55 
56 class Assembly
57 {
58 public:
59                 Assembly(size_t size);
60     virtual     ~Assembly();
61 
62     ssize_t     size() const;
63     uint32_t*   base() const;
64     ssize_t     resize(size_t size);
65 
66     // protocol for sp<>
67             void    incStrong(const void* id) const;
68             void    decStrong(const void* id) const;
69     typedef void    weakref_type;
70 
71 private:
72     mutable int32_t     mCount;
73             uint32_t*   mBase;
74             size_t      mSize;
75 };
76 
77 // ----------------------------------------------------------------------------
78 
79 class CodeCache
80 {
81 public:
82 // pretty simple cache API...
83                 CodeCache(size_t size);
84                 ~CodeCache();
85 
86             sp<Assembly>        lookup(const AssemblyKeyBase& key) const;
87 
88             int                 cache(  const AssemblyKeyBase& key,
89                                         const sp<Assembly>& assembly);
90 
91 private:
92     // nothing to see here...
93     struct cache_entry_t {
cache_entry_tcache_entry_t94         inline cache_entry_t() { }
cache_entry_tcache_entry_t95         inline cache_entry_t(const sp<Assembly>& a, int64_t w)
96                 : entry(a), when(w) { }
97         sp<Assembly>            entry;
98         mutable int64_t         when;
99     };
100 
101     class key_t {
102         friend int compare_type(
103             const key_value_pair_t<key_t, cache_entry_t>&,
104             const key_value_pair_t<key_t, cache_entry_t>&);
105         const AssemblyKeyBase* mKey;
106     public:
key_t()107         key_t() { };
key_t(const AssemblyKeyBase & k)108         key_t(const AssemblyKeyBase& k) : mKey(&k)  { }
109     };
110 
111     mutable pthread_mutex_t             mLock;
112     mutable int64_t                     mWhen;
113     size_t                              mCacheSize;
114     size_t                              mCacheInUse;
115     KeyedVector<key_t, cache_entry_t>   mCacheData;
116 
117     friend int compare_type(
118         const key_value_pair_t<key_t, cache_entry_t>&,
119         const key_value_pair_t<key_t, cache_entry_t>&);
120 };
121 
122 // KeyedVector uses compare_type(), which is more efficient, than
123 // just using operator < ()
compare_type(const key_value_pair_t<CodeCache::key_t,CodeCache::cache_entry_t> & lhs,const key_value_pair_t<CodeCache::key_t,CodeCache::cache_entry_t> & rhs)124 inline int compare_type(
125     const key_value_pair_t<CodeCache::key_t, CodeCache::cache_entry_t>& lhs,
126     const key_value_pair_t<CodeCache::key_t, CodeCache::cache_entry_t>& rhs)
127 {
128     return lhs.key.mKey->compare_type(*(rhs.key.mKey));
129 }
130 
131 // ----------------------------------------------------------------------------
132 
133 }; // namespace android
134 
135 #endif //ANDROID_CODECACHE_H
136