1 /*
2  * Copyright (C) 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <algorithm>
18 #include <ostream>
19 
20 #include "compiled_method_storage.h"
21 
22 #include <android-base/logging.h>
23 
24 #include "base/utils.h"
25 #include "compiled_method.h"
26 #include "linker/linker_patch.h"
27 #include "thread-current-inl.h"
28 #include "utils/dedupe_set-inl.h"
29 #include "utils/swap_space.h"
30 
31 namespace art {
32 
33 namespace {  // anonymous namespace
34 
35 template <typename T>
CopyArray(SwapSpace * swap_space,const ArrayRef<const T> & array)36 const LengthPrefixedArray<T>* CopyArray(SwapSpace* swap_space, const ArrayRef<const T>& array) {
37   DCHECK(!array.empty());
38   SwapAllocator<uint8_t> allocator(swap_space);
39   void* storage = allocator.allocate(LengthPrefixedArray<T>::ComputeSize(array.size()));
40   LengthPrefixedArray<T>* array_copy = new(storage) LengthPrefixedArray<T>(array.size());
41   std::copy(array.begin(), array.end(), array_copy->begin());
42   return array_copy;
43 }
44 
45 template <typename T>
ReleaseArray(SwapSpace * swap_space,const LengthPrefixedArray<T> * array)46 void ReleaseArray(SwapSpace* swap_space, const LengthPrefixedArray<T>* array) {
47   SwapAllocator<uint8_t> allocator(swap_space);
48   size_t size = LengthPrefixedArray<T>::ComputeSize(array->size());
49   array->~LengthPrefixedArray<T>();
50   allocator.deallocate(const_cast<uint8_t*>(reinterpret_cast<const uint8_t*>(array)), size);
51 }
52 
53 }  // anonymous namespace
54 
55 template <typename T, typename DedupeSetType>
AllocateOrDeduplicateArray(const ArrayRef<const T> & data,DedupeSetType * dedupe_set)56 inline const LengthPrefixedArray<T>* CompiledMethodStorage::AllocateOrDeduplicateArray(
57     const ArrayRef<const T>& data,
58     DedupeSetType* dedupe_set) {
59   if (data.empty()) {
60     return nullptr;
61   } else if (!DedupeEnabled()) {
62     return CopyArray(swap_space_.get(), data);
63   } else {
64     return dedupe_set->Add(Thread::Current(), data);
65   }
66 }
67 
68 template <typename T>
ReleaseArrayIfNotDeduplicated(const LengthPrefixedArray<T> * array)69 inline void CompiledMethodStorage::ReleaseArrayIfNotDeduplicated(
70     const LengthPrefixedArray<T>* array) {
71   if (array != nullptr && !DedupeEnabled()) {
72     ReleaseArray(swap_space_.get(), array);
73   }
74 }
75 
76 template <typename ContentType>
77 class CompiledMethodStorage::DedupeHashFunc {
78  private:
79   static constexpr bool kUseMurmur3Hash = true;
80 
81  public:
operator ()(const ArrayRef<ContentType> & array) const82   size_t operator()(const ArrayRef<ContentType>& array) const {
83     const uint8_t* data = reinterpret_cast<const uint8_t*>(array.data());
84     // TODO: More reasonable assertion.
85     // static_assert(IsPowerOfTwo(sizeof(ContentType)),
86     //    "ContentType is not power of two, don't know whether array layout is as assumed");
87     uint32_t len = sizeof(ContentType) * array.size();
88     if (kUseMurmur3Hash) {
89       static constexpr uint32_t c1 = 0xcc9e2d51;
90       static constexpr uint32_t c2 = 0x1b873593;
91       static constexpr uint32_t r1 = 15;
92       static constexpr uint32_t r2 = 13;
93       static constexpr uint32_t m = 5;
94       static constexpr uint32_t n = 0xe6546b64;
95 
96       uint32_t hash = 0;
97 
98       const int nblocks = len / 4;
99       typedef __attribute__((__aligned__(1))) uint32_t unaligned_uint32_t;
100       const unaligned_uint32_t *blocks = reinterpret_cast<const uint32_t*>(data);
101       int i;
102       for (i = 0; i < nblocks; i++) {
103         uint32_t k = blocks[i];
104         k *= c1;
105         k = (k << r1) | (k >> (32 - r1));
106         k *= c2;
107 
108         hash ^= k;
109         hash = ((hash << r2) | (hash >> (32 - r2))) * m + n;
110       }
111 
112       const uint8_t *tail = reinterpret_cast<const uint8_t*>(data + nblocks * 4);
113       uint32_t k1 = 0;
114 
115       switch (len & 3) {
116         case 3:
117           k1 ^= tail[2] << 16;
118           FALLTHROUGH_INTENDED;
119         case 2:
120           k1 ^= tail[1] << 8;
121           FALLTHROUGH_INTENDED;
122         case 1:
123           k1 ^= tail[0];
124 
125           k1 *= c1;
126           k1 = (k1 << r1) | (k1 >> (32 - r1));
127           k1 *= c2;
128           hash ^= k1;
129       }
130 
131       hash ^= len;
132       hash ^= (hash >> 16);
133       hash *= 0x85ebca6b;
134       hash ^= (hash >> 13);
135       hash *= 0xc2b2ae35;
136       hash ^= (hash >> 16);
137 
138       return hash;
139     } else {
140       return HashBytes(data, len);
141     }
142   }
143 };
144 
145 template <typename T>
146 class CompiledMethodStorage::LengthPrefixedArrayAlloc {
147  public:
LengthPrefixedArrayAlloc(SwapSpace * swap_space)148   explicit LengthPrefixedArrayAlloc(SwapSpace* swap_space)
149       : swap_space_(swap_space) {
150   }
151 
Copy(const ArrayRef<const T> & array)152   const LengthPrefixedArray<T>* Copy(const ArrayRef<const T>& array) {
153     return CopyArray(swap_space_, array);
154   }
155 
Destroy(const LengthPrefixedArray<T> * array)156   void Destroy(const LengthPrefixedArray<T>* array) {
157     ReleaseArray(swap_space_, array);
158   }
159 
160  private:
161   SwapSpace* const swap_space_;
162 };
163 
CompiledMethodStorage(int swap_fd)164 CompiledMethodStorage::CompiledMethodStorage(int swap_fd)
165     : swap_space_(swap_fd == -1 ? nullptr : new SwapSpace(swap_fd, 10 * MB)),
166       dedupe_enabled_(true),
167       dedupe_code_("dedupe code", LengthPrefixedArrayAlloc<uint8_t>(swap_space_.get())),
168       dedupe_method_info_("dedupe method info",
169                           LengthPrefixedArrayAlloc<uint8_t>(swap_space_.get())),
170       dedupe_vmap_table_("dedupe vmap table",
171                          LengthPrefixedArrayAlloc<uint8_t>(swap_space_.get())),
172       dedupe_cfi_info_("dedupe cfi info", LengthPrefixedArrayAlloc<uint8_t>(swap_space_.get())),
173       dedupe_linker_patches_("dedupe cfi info",
174                              LengthPrefixedArrayAlloc<linker::LinkerPatch>(swap_space_.get())) {
175 }
176 
~CompiledMethodStorage()177 CompiledMethodStorage::~CompiledMethodStorage() {
178   // All done by member destructors.
179 }
180 
DumpMemoryUsage(std::ostream & os,bool extended) const181 void CompiledMethodStorage::DumpMemoryUsage(std::ostream& os, bool extended) const {
182   if (swap_space_.get() != nullptr) {
183     const size_t swap_size = swap_space_->GetSize();
184     os << " swap=" << PrettySize(swap_size) << " (" << swap_size << "B)";
185   }
186   if (extended) {
187     Thread* self = Thread::Current();
188     os << "\nCode dedupe: " << dedupe_code_.DumpStats(self);
189     os << "\nVmap table dedupe: " << dedupe_vmap_table_.DumpStats(self);
190     os << "\nCFI info dedupe: " << dedupe_cfi_info_.DumpStats(self);
191   }
192 }
193 
DeduplicateCode(const ArrayRef<const uint8_t> & code)194 const LengthPrefixedArray<uint8_t>* CompiledMethodStorage::DeduplicateCode(
195     const ArrayRef<const uint8_t>& code) {
196   return AllocateOrDeduplicateArray(code, &dedupe_code_);
197 }
198 
ReleaseCode(const LengthPrefixedArray<uint8_t> * code)199 void CompiledMethodStorage::ReleaseCode(const LengthPrefixedArray<uint8_t>* code) {
200   ReleaseArrayIfNotDeduplicated(code);
201 }
202 
DeduplicateMethodInfo(const ArrayRef<const uint8_t> & src_map)203 const LengthPrefixedArray<uint8_t>* CompiledMethodStorage::DeduplicateMethodInfo(
204     const ArrayRef<const uint8_t>& src_map) {
205   return AllocateOrDeduplicateArray(src_map, &dedupe_method_info_);
206 }
207 
ReleaseMethodInfo(const LengthPrefixedArray<uint8_t> * method_info)208 void CompiledMethodStorage::ReleaseMethodInfo(const LengthPrefixedArray<uint8_t>* method_info) {
209   ReleaseArrayIfNotDeduplicated(method_info);
210 }
211 
DeduplicateVMapTable(const ArrayRef<const uint8_t> & table)212 const LengthPrefixedArray<uint8_t>* CompiledMethodStorage::DeduplicateVMapTable(
213     const ArrayRef<const uint8_t>& table) {
214   return AllocateOrDeduplicateArray(table, &dedupe_vmap_table_);
215 }
216 
ReleaseVMapTable(const LengthPrefixedArray<uint8_t> * table)217 void CompiledMethodStorage::ReleaseVMapTable(const LengthPrefixedArray<uint8_t>* table) {
218   ReleaseArrayIfNotDeduplicated(table);
219 }
220 
DeduplicateCFIInfo(const ArrayRef<const uint8_t> & cfi_info)221 const LengthPrefixedArray<uint8_t>* CompiledMethodStorage::DeduplicateCFIInfo(
222     const ArrayRef<const uint8_t>& cfi_info) {
223   return AllocateOrDeduplicateArray(cfi_info, &dedupe_cfi_info_);
224 }
225 
ReleaseCFIInfo(const LengthPrefixedArray<uint8_t> * cfi_info)226 void CompiledMethodStorage::ReleaseCFIInfo(const LengthPrefixedArray<uint8_t>* cfi_info) {
227   ReleaseArrayIfNotDeduplicated(cfi_info);
228 }
229 
DeduplicateLinkerPatches(const ArrayRef<const linker::LinkerPatch> & linker_patches)230 const LengthPrefixedArray<linker::LinkerPatch>* CompiledMethodStorage::DeduplicateLinkerPatches(
231     const ArrayRef<const linker::LinkerPatch>& linker_patches) {
232   return AllocateOrDeduplicateArray(linker_patches, &dedupe_linker_patches_);
233 }
234 
ReleaseLinkerPatches(const LengthPrefixedArray<linker::LinkerPatch> * linker_patches)235 void CompiledMethodStorage::ReleaseLinkerPatches(
236     const LengthPrefixedArray<linker::LinkerPatch>* linker_patches) {
237   ReleaseArrayIfNotDeduplicated(linker_patches);
238 }
239 
240 }  // namespace art
241