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 #include "array.h"
18 
19 #include "class.h"
20 #include "class-inl.h"
21 #include "class_linker-inl.h"
22 #include "common_throws.h"
23 #include "dex_file-inl.h"
24 #include "gc/accounting/card_table-inl.h"
25 #include "object-inl.h"
26 #include "object_array.h"
27 #include "object_array-inl.h"
28 #include "handle_scope-inl.h"
29 #include "thread.h"
30 #include "utils.h"
31 
32 namespace art {
33 namespace mirror {
34 
35 // Create a multi-dimensional array of Objects or primitive types.
36 //
37 // We have to generate the names for X[], X[][], X[][][], and so on.  The
38 // easiest way to deal with that is to create the full name once and then
39 // subtract pieces off.  Besides, we want to start with the outermost
40 // piece and work our way in.
41 // Recursively create an array with multiple dimensions.  Elements may be
42 // Objects or primitive types.
RecursiveCreateMultiArray(Thread * self,Handle<Class> array_class,int current_dimension,Handle<mirror::IntArray> dimensions)43 static Array* RecursiveCreateMultiArray(Thread* self,
44                                         Handle<Class> array_class, int current_dimension,
45                                         Handle<mirror::IntArray> dimensions)
46     SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
47   int32_t array_length = dimensions->Get(current_dimension);
48   StackHandleScope<1> hs(self);
49   Handle<Array> new_array(
50       hs.NewHandle(
51           Array::Alloc<true>(self, array_class.Get(), array_length,
52                              array_class->GetComponentSizeShift(),
53                              Runtime::Current()->GetHeap()->GetCurrentAllocator())));
54   if (UNLIKELY(new_array.Get() == nullptr)) {
55     CHECK(self->IsExceptionPending());
56     return nullptr;
57   }
58   if (current_dimension + 1 < dimensions->GetLength()) {
59     // Create a new sub-array in every element of the array.
60     for (int32_t i = 0; i < array_length; i++) {
61       StackHandleScope<1> hs2(self);
62       Handle<mirror::Class> h_component_type(hs2.NewHandle(array_class->GetComponentType()));
63       Array* sub_array = RecursiveCreateMultiArray(self, h_component_type,
64                                                    current_dimension + 1, dimensions);
65       if (UNLIKELY(sub_array == nullptr)) {
66         CHECK(self->IsExceptionPending());
67         return nullptr;
68       }
69       // Use non-transactional mode without check.
70       new_array->AsObjectArray<Array>()->Set<false, false>(i, sub_array);
71     }
72   }
73   return new_array.Get();
74 }
75 
CreateMultiArray(Thread * self,Handle<Class> element_class,Handle<IntArray> dimensions)76 Array* Array::CreateMultiArray(Thread* self, Handle<Class> element_class,
77                                Handle<IntArray> dimensions) {
78   // Verify dimensions.
79   //
80   // The caller is responsible for verifying that "dimArray" is non-null
81   // and has a length > 0 and <= 255.
82   int num_dimensions = dimensions->GetLength();
83   DCHECK_GT(num_dimensions, 0);
84   DCHECK_LE(num_dimensions, 255);
85 
86   for (int i = 0; i < num_dimensions; i++) {
87     int dimension = dimensions->Get(i);
88     if (UNLIKELY(dimension < 0)) {
89       ThrowNegativeArraySizeException(StringPrintf("Dimension %d: %d", i, dimension).c_str());
90       return nullptr;
91     }
92   }
93 
94   // Find/generate the array class.
95   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
96   mirror::Class* element_class_ptr = element_class.Get();
97   StackHandleScope<1> hs(self);
98   MutableHandle<mirror::Class> array_class(
99       hs.NewHandle(class_linker->FindArrayClass(self, &element_class_ptr)));
100   if (UNLIKELY(array_class.Get() == nullptr)) {
101     CHECK(self->IsExceptionPending());
102     return nullptr;
103   }
104   for (int32_t i = 1; i < dimensions->GetLength(); ++i) {
105     mirror::Class* array_class_ptr = array_class.Get();
106     array_class.Assign(class_linker->FindArrayClass(self, &array_class_ptr));
107     if (UNLIKELY(array_class.Get() == nullptr)) {
108       CHECK(self->IsExceptionPending());
109       return nullptr;
110     }
111   }
112   // Create the array.
113   Array* new_array = RecursiveCreateMultiArray(self, array_class, 0, dimensions);
114   if (UNLIKELY(new_array == nullptr)) {
115     CHECK(self->IsExceptionPending());
116   }
117   return new_array;
118 }
119 
ThrowArrayIndexOutOfBoundsException(int32_t index)120 void Array::ThrowArrayIndexOutOfBoundsException(int32_t index) {
121   art::ThrowArrayIndexOutOfBoundsException(index, GetLength());
122 }
123 
ThrowArrayStoreException(Object * object)124 void Array::ThrowArrayStoreException(Object* object) {
125   art::ThrowArrayStoreException(object->GetClass(), this->GetClass());
126 }
127 
CopyOf(Thread * self,int32_t new_length)128 Array* Array::CopyOf(Thread* self, int32_t new_length) {
129   CHECK(GetClass()->GetComponentType()->IsPrimitive()) << "Will miss write barriers";
130   DCHECK_GE(new_length, 0);
131   // We may get copied by a compacting GC.
132   StackHandleScope<1> hs(self);
133   auto h_this(hs.NewHandle(this));
134   auto* heap = Runtime::Current()->GetHeap();
135   gc::AllocatorType allocator_type = heap->IsMovableObject(this) ? heap->GetCurrentAllocator() :
136       heap->GetCurrentNonMovingAllocator();
137   const auto component_size = GetClass()->GetComponentSize();
138   const auto component_shift = GetClass()->GetComponentSizeShift();
139   Array* new_array = Alloc<true>(self, GetClass(), new_length, component_shift, allocator_type);
140   if (LIKELY(new_array != nullptr)) {
141     memcpy(new_array->GetRawData(component_size, 0), h_this->GetRawData(component_size, 0),
142            std::min(h_this->GetLength(), new_length) << component_shift);
143   }
144   return new_array;
145 }
146 
147 
148 template <typename T> GcRoot<Class> PrimitiveArray<T>::array_class_;
149 
150 // Explicitly instantiate all the primitive array types.
151 template class PrimitiveArray<uint8_t>;   // BooleanArray
152 template class PrimitiveArray<int8_t>;    // ByteArray
153 template class PrimitiveArray<uint16_t>;  // CharArray
154 template class PrimitiveArray<double>;    // DoubleArray
155 template class PrimitiveArray<float>;     // FloatArray
156 template class PrimitiveArray<int32_t>;   // IntArray
157 template class PrimitiveArray<int64_t>;   // LongArray
158 template class PrimitiveArray<int16_t>;   // ShortArray
159 
160 }  // namespace mirror
161 }  // namespace art
162