1 /*
2  * Copyright (C) 2011 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 #ifndef ART_RUNTIME_MIRROR_ARRAY_H_
18 #define ART_RUNTIME_MIRROR_ARRAY_H_
19 
20 #include "base/bit_utils.h"
21 #include "base/enums.h"
22 #include "obj_ptr.h"
23 #include "object.h"
24 
25 namespace art {
26 
27 namespace gc {
28 enum AllocatorType : char;
29 }  // namespace gc
30 
31 template<class T> class Handle;
32 class Thread;
33 
34 namespace mirror {
35 
36 class MANAGED Array : public Object {
37  public:
38   static constexpr size_t kFirstElementOffset = 12u;
39 
40   // The size of a java.lang.Class representing an array.
41   static uint32_t ClassSize(PointerSize pointer_size);
42 
43   // Allocates an array with the given properties, if kFillUsable is true the array will be of at
44   // least component_count size, however, if there's usable space at the end of the allocation the
45   // array will fill it.
46   template <bool kIsInstrumented = true, bool kFillUsable = false>
47   ALWAYS_INLINE static ObjPtr<Array> Alloc(Thread* self,
48                                            ObjPtr<Class> array_class,
49                                            int32_t component_count,
50                                            size_t component_size_shift,
51                                            gc::AllocatorType allocator_type)
52       REQUIRES_SHARED(Locks::mutator_lock_)
53       REQUIRES(!Roles::uninterruptible_);
54 
55   static ObjPtr<Array> CreateMultiArray(Thread* self,
56                                         Handle<Class> element_class,
57                                         Handle<IntArray> dimensions)
58       REQUIRES_SHARED(Locks::mutator_lock_)
59       REQUIRES(!Roles::uninterruptible_);
60 
61   template<VerifyObjectFlags kVerifyFlags = kDefaultVerifyFlags>
62   size_t SizeOf() REQUIRES_SHARED(Locks::mutator_lock_);
63   template<VerifyObjectFlags kVerifyFlags = kDefaultVerifyFlags>
GetLength()64   ALWAYS_INLINE int32_t GetLength() REQUIRES_SHARED(Locks::mutator_lock_) {
65     return GetField32<kVerifyFlags>(OFFSET_OF_OBJECT_MEMBER(Array, length_));
66   }
67 
SetLength(int32_t length)68   void SetLength(int32_t length) REQUIRES_SHARED(Locks::mutator_lock_) {
69     DCHECK_GE(length, 0);
70     // We use non transactional version since we can't undo this write. We also disable checking
71     // since it would fail during a transaction.
72     SetField32<false, false, kVerifyNone>(OFFSET_OF_OBJECT_MEMBER(Array, length_), length);
73   }
74 
LengthOffset()75   static constexpr MemberOffset LengthOffset() {
76     return OFFSET_OF_OBJECT_MEMBER(Array, length_);
77   }
78 
DataOffset(size_t component_size)79   static constexpr MemberOffset DataOffset(size_t component_size) {
80     DCHECK(IsPowerOfTwo(component_size)) << component_size;
81     size_t data_offset = RoundUp(OFFSETOF_MEMBER(Array, first_element_), component_size);
82     DCHECK_EQ(RoundUp(data_offset, component_size), data_offset)
83         << "Array data offset isn't aligned with component size";
84     return MemberOffset(data_offset);
85   }
86   template <size_t kComponentSize>
DataOffset()87   static constexpr MemberOffset DataOffset() {
88     static_assert(IsPowerOfTwo(kComponentSize), "Invalid component size");
89     constexpr size_t data_offset = RoundUp(kFirstElementOffset, kComponentSize);
90     static_assert(RoundUp(data_offset, kComponentSize) == data_offset, "RoundUp fail");
91     return MemberOffset(data_offset);
92   }
93 
FirstElementOffset()94   static constexpr size_t FirstElementOffset() {
95     return OFFSETOF_MEMBER(Array, first_element_);
96   }
97 
GetRawData(size_t component_size,int32_t index)98   void* GetRawData(size_t component_size, int32_t index)
99       REQUIRES_SHARED(Locks::mutator_lock_) {
100     intptr_t data = reinterpret_cast<intptr_t>(this) + DataOffset(component_size).Int32Value() +
101         + (index * component_size);
102     return reinterpret_cast<void*>(data);
103   }
104   template <size_t kComponentSize>
GetRawData(int32_t index)105   void* GetRawData(int32_t index) REQUIRES_SHARED(Locks::mutator_lock_) {
106     intptr_t data = reinterpret_cast<intptr_t>(this) + DataOffset<kComponentSize>().Int32Value() +
107         + (index * kComponentSize);
108     return reinterpret_cast<void*>(data);
109   }
110 
GetRawData(size_t component_size,int32_t index)111   const void* GetRawData(size_t component_size, int32_t index) const {
112     intptr_t data = reinterpret_cast<intptr_t>(this) + DataOffset(component_size).Int32Value() +
113         + (index * component_size);
114     return reinterpret_cast<void*>(data);
115   }
116   template <size_t kComponentSize>
GetRawData(int32_t index)117   const void* GetRawData(int32_t index) const {
118     intptr_t data = reinterpret_cast<intptr_t>(this) + DataOffset<kComponentSize>().Int32Value() +
119         + (index * kComponentSize);
120     return reinterpret_cast<void*>(data);
121   }
122 
123   // Returns true if the index is valid. If not, throws an ArrayIndexOutOfBoundsException and
124   // returns false.
125   template<VerifyObjectFlags kVerifyFlags = kDefaultVerifyFlags>
126   ALWAYS_INLINE bool CheckIsValidIndex(int32_t index) REQUIRES_SHARED(Locks::mutator_lock_);
127 
128   static ObjPtr<Array> CopyOf(Handle<Array> h_this, Thread* self, int32_t new_length)
129       REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_);
130 
131  protected:
132   void ThrowArrayStoreException(ObjPtr<Object> object) REQUIRES_SHARED(Locks::mutator_lock_)
133       REQUIRES(!Roles::uninterruptible_);
134 
135  private:
136   void ThrowArrayIndexOutOfBoundsException(int32_t index)
137       REQUIRES_SHARED(Locks::mutator_lock_);
138 
139   // The number of array elements.
140   // We only use the field indirectly using the LengthOffset() method.
141   int32_t length_ ATTRIBUTE_UNUSED;
142   // Marker for the data (used by generated code)
143   // We only use the field indirectly using the DataOffset() method.
144   uint32_t first_element_[0] ATTRIBUTE_UNUSED;
145 
146   DISALLOW_IMPLICIT_CONSTRUCTORS(Array);
147 };
148 
149 template<typename T>
150 class MANAGED PrimitiveArray : public Array {
151  public:
152   typedef T ElementType;
153 
154   static ObjPtr<PrimitiveArray<T>> Alloc(Thread* self, size_t length)
155       REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_);
156 
157   static ObjPtr<PrimitiveArray<T>> AllocateAndFill(Thread* self, const T* data, size_t length)
158       REQUIRES_SHARED(Locks::mutator_lock_) REQUIRES(!Roles::uninterruptible_);
159 
160 
GetData()161   const T* GetData() const ALWAYS_INLINE  REQUIRES_SHARED(Locks::mutator_lock_) {
162     return reinterpret_cast<const T*>(GetRawData<sizeof(T)>(0));
163   }
164 
GetData()165   T* GetData() ALWAYS_INLINE REQUIRES_SHARED(Locks::mutator_lock_) {
166     return reinterpret_cast<T*>(GetRawData<sizeof(T)>(0));
167   }
168 
169   T Get(int32_t i) ALWAYS_INLINE REQUIRES_SHARED(Locks::mutator_lock_);
170 
GetWithoutChecks(int32_t i)171   T GetWithoutChecks(int32_t i) ALWAYS_INLINE REQUIRES_SHARED(Locks::mutator_lock_) {
172     DCHECK(CheckIsValidIndex(i)) << "i=" << i << " length=" << GetLength();
173     return GetData()[i];
174   }
175 
176   void Set(int32_t i, T value) ALWAYS_INLINE REQUIRES_SHARED(Locks::mutator_lock_);
177 
178   // TODO fix thread safety analysis broken by the use of template. This should be
179   // REQUIRES_SHARED(Locks::mutator_lock_).
180   template<bool kTransactionActive, bool kCheckTransaction = true>
181   void Set(int32_t i, T value) ALWAYS_INLINE NO_THREAD_SAFETY_ANALYSIS;
182 
183   // TODO fix thread safety analysis broken by the use of template. This should be
184   // REQUIRES_SHARED(Locks::mutator_lock_).
185   template<bool kTransactionActive,
186            bool kCheckTransaction = true,
187            VerifyObjectFlags kVerifyFlags = kDefaultVerifyFlags>
188   void SetWithoutChecks(int32_t i, T value) ALWAYS_INLINE NO_THREAD_SAFETY_ANALYSIS;
189 
190   /*
191    * Works like memmove(), except we guarantee not to allow tearing of array values (ie using
192    * smaller than element size copies). Arguments are assumed to be within the bounds of the array
193    * and the arrays non-null.
194    */
195   void Memmove(int32_t dst_pos, ObjPtr<PrimitiveArray<T>> src, int32_t src_pos, int32_t count)
196       REQUIRES_SHARED(Locks::mutator_lock_);
197 
198   /*
199    * Works like memcpy(), except we guarantee not to allow tearing of array values (ie using
200    * smaller than element size copies). Arguments are assumed to be within the bounds of the array
201    * and the arrays non-null.
202    */
203   void Memcpy(int32_t dst_pos, ObjPtr<PrimitiveArray<T>> src, int32_t src_pos, int32_t count)
204       REQUIRES_SHARED(Locks::mutator_lock_);
205 
206  private:
207   DISALLOW_IMPLICIT_CONSTRUCTORS(PrimitiveArray);
208 };
209 
210 // Declare the different primitive arrays. Instantiations will be in array.cc.
211 extern template class PrimitiveArray<uint8_t>;   // BooleanArray
212 extern template class PrimitiveArray<int8_t>;    // ByteArray
213 extern template class PrimitiveArray<uint16_t>;  // CharArray
214 extern template class PrimitiveArray<double>;    // DoubleArray
215 extern template class PrimitiveArray<float>;     // FloatArray
216 extern template class PrimitiveArray<int32_t>;   // IntArray
217 extern template class PrimitiveArray<int64_t>;   // LongArray
218 extern template class PrimitiveArray<int16_t>;   // ShortArray
219 
220 // Either an IntArray or a LongArray.
221 class PointerArray : public Array {
222  public:
223   template<typename T, VerifyObjectFlags kVerifyFlags = kVerifyNone>
224   T GetElementPtrSize(uint32_t idx, PointerSize ptr_size)
225       REQUIRES_SHARED(Locks::mutator_lock_);
226   template<typename T, PointerSize kPtrSize, VerifyObjectFlags kVerifyFlags = kVerifyNone>
227   T GetElementPtrSize(uint32_t idx)
228       REQUIRES_SHARED(Locks::mutator_lock_);
229   // Same as GetElementPtrSize, but uses unchecked version of array conversion. It is thus not
230   // checked whether kPtrSize matches the underlying array. Only use after at least one invocation
231   // of GetElementPtrSize!
232   template<typename T, PointerSize kPtrSize, VerifyObjectFlags kVerifyFlags = kVerifyNone>
233   T GetElementPtrSizeUnchecked(uint32_t idx)
234       REQUIRES_SHARED(Locks::mutator_lock_);
235 
236   template<VerifyObjectFlags kVerifyFlags = kVerifyNone>
ElementAddress(size_t index,PointerSize ptr_size)237   void** ElementAddress(size_t index, PointerSize ptr_size) REQUIRES_SHARED(Locks::mutator_lock_) {
238     DCHECK_LT(index, static_cast<size_t>(GetLength<kVerifyFlags>()));
239     return reinterpret_cast<void**>(reinterpret_cast<uint8_t*>(this) +
240                                     Array::DataOffset(static_cast<size_t>(ptr_size)).Uint32Value() +
241                                     static_cast<size_t>(ptr_size) * index);
242   }
243 
244   template<bool kTransactionActive = false, bool kCheckTransaction = true, bool kUnchecked = false>
245   void SetElementPtrSize(uint32_t idx, uint64_t element, PointerSize ptr_size)
246       REQUIRES_SHARED(Locks::mutator_lock_);
247   template<bool kTransactionActive = false,
248            bool kCheckTransaction = true,
249            bool kUnchecked = false,
250            typename T>
251   void SetElementPtrSize(uint32_t idx, T* element, PointerSize ptr_size)
252       REQUIRES_SHARED(Locks::mutator_lock_);
253 
254   // Fixup the pointers in the dest arrays by passing our pointers through the visitor. Only copies
255   // to dest if visitor(source_ptr) != source_ptr.
256   template <VerifyObjectFlags kVerifyFlags = kVerifyNone, typename Visitor>
257   void Fixup(ObjPtr<mirror::PointerArray> dest, PointerSize pointer_size, const Visitor& visitor)
258       REQUIRES_SHARED(Locks::mutator_lock_);
259 
260   // Works like memcpy(), except we guarantee not to allow tearing of array values (ie using smaller
261   // than element size copies). Arguments are assumed to be within the bounds of the array and the
262   // arrays non-null. Cannot be called in an active transaction.
263   template<bool kUnchecked = false>
264   void Memcpy(int32_t dst_pos,
265               ObjPtr<PointerArray> src,
266               int32_t src_pos,
267               int32_t count,
268               PointerSize pointer_size)
269       REQUIRES_SHARED(Locks::mutator_lock_);
270 };
271 
272 }  // namespace mirror
273 }  // namespace art
274 
275 #endif  // ART_RUNTIME_MIRROR_ARRAY_H_
276