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_COMPILER_IMAGE_WRITER_H_ 18 #define ART_COMPILER_IMAGE_WRITER_H_ 19 20 #include <stdint.h> 21 22 #include <cstddef> 23 #include <memory> 24 #include <set> 25 #include <string> 26 27 #include "base/macros.h" 28 #include "driver/compiler_driver.h" 29 #include "gc/space/space.h" 30 #include "mem_map.h" 31 #include "oat_file.h" 32 #include "mirror/dex_cache.h" 33 #include "os.h" 34 #include "safe_map.h" 35 #include "gc/space/space.h" 36 #include "utils.h" 37 38 namespace art { 39 40 // Write a Space built during compilation for use during execution. 41 class ImageWriter FINAL { 42 public: ImageWriter(const CompilerDriver & compiler_driver)43 explicit ImageWriter(const CompilerDriver& compiler_driver) 44 : compiler_driver_(compiler_driver), oat_file_(NULL), image_end_(0), 45 image_objects_offset_begin_(0), image_begin_(NULL), 46 oat_data_begin_(NULL), interpreter_to_interpreter_bridge_offset_(0), 47 interpreter_to_compiled_code_bridge_offset_(0), portable_imt_conflict_trampoline_offset_(0), 48 portable_resolution_trampoline_offset_(0), quick_generic_jni_trampoline_offset_(0), 49 quick_imt_conflict_trampoline_offset_(0), quick_resolution_trampoline_offset_(0), 50 compile_pic_(false), target_ptr_size_(0), bin_slot_sizes_(), bin_slot_count_() {} 51 ~ImageWriter()52 ~ImageWriter() {} 53 54 bool Write(const std::string& image_filename, 55 uintptr_t image_begin, 56 const std::string& oat_filename, 57 const std::string& oat_location, 58 bool compile_pic) 59 LOCKS_EXCLUDED(Locks::mutator_lock_); 60 GetOatDataBegin()61 uintptr_t GetOatDataBegin() { 62 return reinterpret_cast<uintptr_t>(oat_data_begin_); 63 } 64 65 private: 66 bool AllocMemory(); 67 68 // Mark the objects defined in this space in the given live bitmap. 69 void RecordImageAllocations() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 70 71 // Classify different kinds of bins that objects end up getting packed into during image writing. 72 enum Bin { 73 // Likely-clean: 74 kBinString, // [String] Almost always immutable (except for obj header). 75 kBinArtMethodsManagedInitialized, // [ArtMethod] Not-native, and initialized. Unlikely to dirty 76 // Unknown mix of clean/dirty: 77 kBinRegular, 78 // Likely-dirty: 79 // All classes get their own bins since their fields often dirty 80 kBinClassInitializedFinalStatics, // Class initializers have been run, no non-final statics 81 kBinClassInitialized, // Class initializers have been run 82 kBinClassVerified, // Class verified, but initializers haven't been run 83 kBinArtMethodNative, // Art method that is actually native 84 kBinArtMethodNotInitialized, // Art method with a declaring class that wasn't initialized 85 // Don't care about other art methods since they don't dirty 86 // Add more bins here if we add more segregation code. 87 kBinSize, 88 }; 89 90 static constexpr size_t kBinBits = MinimumBitsToStore(kBinSize - 1); 91 // uint32 = typeof(lockword_) 92 static constexpr size_t kBinShift = BitSizeOf<uint32_t>() - kBinBits; 93 // 111000.....0 94 static constexpr size_t kBinMask = ((static_cast<size_t>(1) << kBinBits) - 1) << kBinShift; 95 96 // We use the lock word to store the bin # and bin index of the object in the image. 97 // 98 // The struct size must be exactly sizeof(LockWord), currently 32-bits, since this will end up 99 // stored in the lock word bit-for-bit when object forwarding addresses are being calculated. 100 struct BinSlot { 101 explicit BinSlot(uint32_t lockword); 102 BinSlot(Bin bin, uint32_t index); 103 104 // The bin an object belongs to, i.e. regular, class/verified, class/initialized, etc. 105 Bin GetBin() const; 106 // The offset in bytes from the beginning of the bin. Aligned to object size. 107 uint32_t GetIndex() const; 108 // Pack into a single uint32_t, for storing into a lock word. uint32_tBinSlot109 explicit operator uint32_t() const { return lockword_; } 110 // Comparison operator for map support 111 bool operator<(const BinSlot& other) const { return lockword_ < other.lockword_; } 112 113 private: 114 // Must be the same size as LockWord, any larger and we would truncate the data. 115 const uint32_t lockword_; 116 }; 117 118 // We use the lock word to store the offset of the object in the image. 119 void AssignImageOffset(mirror::Object* object, BinSlot bin_slot) 120 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 121 void SetImageOffset(mirror::Object* object, BinSlot bin_slot, size_t offset) 122 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 123 bool IsImageOffsetAssigned(mirror::Object* object) const 124 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 125 size_t GetImageOffset(mirror::Object* object) const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 126 127 void AssignImageBinSlot(mirror::Object* object) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 128 void SetImageBinSlot(mirror::Object* object, BinSlot bin_slot) 129 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 130 bool IsImageBinSlotAssigned(mirror::Object* object) const 131 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 132 BinSlot GetImageBinSlot(mirror::Object* object) const SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 133 GetImageAddressCallback(void * writer,mirror::Object * obj)134 static void* GetImageAddressCallback(void* writer, mirror::Object* obj) 135 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 136 return reinterpret_cast<ImageWriter*>(writer)->GetImageAddress(obj); 137 } 138 GetImageAddress(mirror::Object * object)139 mirror::Object* GetImageAddress(mirror::Object* object) const 140 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 141 if (object == NULL) { 142 return NULL; 143 } 144 return reinterpret_cast<mirror::Object*>(image_begin_ + GetImageOffset(object)); 145 } 146 GetLocalAddress(mirror::Object * object)147 mirror::Object* GetLocalAddress(mirror::Object* object) const 148 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { 149 size_t offset = GetImageOffset(object); 150 byte* dst = image_->Begin() + offset; 151 return reinterpret_cast<mirror::Object*>(dst); 152 } 153 GetOatAddress(uint32_t offset)154 const byte* GetOatAddress(uint32_t offset) const { 155 #if !defined(ART_USE_PORTABLE_COMPILER) 156 // With Quick, code is within the OatFile, as there are all in one 157 // .o ELF object. However with Portable, the code is always in 158 // different .o ELF objects. 159 DCHECK_LT(offset, oat_file_->Size()); 160 #endif 161 if (offset == 0u) { 162 return nullptr; 163 } 164 return oat_data_begin_ + offset; 165 } 166 167 // Returns true if the class was in the original requested image classes list. 168 bool IsImageClass(mirror::Class* klass) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 169 170 // Debug aid that list of requested image classes. 171 void DumpImageClasses(); 172 173 // Preinitializes some otherwise lazy fields (such as Class name) to avoid runtime image dirtying. 174 void ComputeLazyFieldsForImageClasses() 175 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 176 static bool ComputeLazyFieldsForClassesVisitor(mirror::Class* klass, void* arg) 177 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 178 179 // Wire dex cache resolved strings to strings in the image to avoid runtime resolution. 180 void ComputeEagerResolvedStrings() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 181 static void ComputeEagerResolvedStringsCallback(mirror::Object* obj, void* arg) 182 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 183 184 // Combine string char arrays. 185 void ProcessStrings() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 186 187 // Remove unwanted classes from various roots. 188 void PruneNonImageClasses() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 189 static bool NonImageClassesVisitor(mirror::Class* c, void* arg) 190 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 191 192 // Verify unwanted classes removed. 193 void CheckNonImageClassesRemoved() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 194 static void CheckNonImageClassesRemovedCallback(mirror::Object* obj, void* arg) 195 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 196 197 // Lays out where the image objects will be at runtime. 198 void CalculateNewObjectOffsets(size_t oat_loaded_size, size_t oat_data_offset) 199 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 200 mirror::ObjectArray<mirror::Object>* CreateImageRoots() const 201 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 202 void CalculateObjectBinSlots(mirror::Object* obj) 203 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 204 void UnbinObjectsIntoOffset(mirror::Object* obj) 205 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 206 207 void WalkInstanceFields(mirror::Object* obj, mirror::Class* klass) 208 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 209 void WalkFieldsInOrder(mirror::Object* obj) 210 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 211 static void WalkFieldsCallback(mirror::Object* obj, void* arg) 212 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 213 static void UnbinObjectsIntoOffsetCallback(mirror::Object* obj, void* arg) 214 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 215 216 // Creates the contiguous image in memory and adjusts pointers. 217 void CopyAndFixupObjects() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 218 static void CopyAndFixupObjectsCallback(mirror::Object* obj, void* arg) 219 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 220 void FixupMethod(mirror::ArtMethod* orig, mirror::ArtMethod* copy) 221 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 222 void FixupObject(mirror::Object* orig, mirror::Object* copy) 223 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 224 225 // Get quick code for non-resolution/imt_conflict/abstract method. 226 const byte* GetQuickCode(mirror::ArtMethod* method, bool* quick_is_interpreted) 227 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 228 229 const byte* GetQuickEntryPoint(mirror::ArtMethod* method) 230 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 231 232 // Patches references in OatFile to expect runtime addresses. 233 void PatchOatCodeAndMethods(File* elf_file) 234 SHARED_LOCKS_REQUIRED(Locks::mutator_lock_); 235 236 // Calculate the sum total of the bin slot sizes in [0, up_to). Defaults to all bins. 237 size_t GetBinSizeSum(Bin up_to = kBinSize) const; 238 239 const CompilerDriver& compiler_driver_; 240 241 // oat file with code for this image 242 OatFile* oat_file_; 243 244 // Memory mapped for generating the image. 245 std::unique_ptr<MemMap> image_; 246 247 // Offset to the free space in image_. 248 size_t image_end_; 249 250 // Offset from image_begin_ to where the first object is in image_. 251 size_t image_objects_offset_begin_; 252 253 // Beginning target image address for the output image. 254 byte* image_begin_; 255 256 // Saved hashes (objects are inside of the image so that they don't move). 257 std::vector<std::pair<mirror::Object*, uint32_t>> saved_hashes_; 258 259 // Saved hashes (objects are bin slots to inside of the image, not yet allocated an address). 260 std::map<BinSlot, uint32_t> saved_hashes_map_; 261 262 // Beginning target oat address for the pointers from the output image to its oat file. 263 const byte* oat_data_begin_; 264 265 // Image bitmap which lets us know where the objects inside of the image reside. 266 std::unique_ptr<gc::accounting::ContinuousSpaceBitmap> image_bitmap_; 267 268 // Offset from oat_data_begin_ to the stubs. 269 uint32_t interpreter_to_interpreter_bridge_offset_; 270 uint32_t interpreter_to_compiled_code_bridge_offset_; 271 uint32_t jni_dlsym_lookup_offset_; 272 uint32_t portable_imt_conflict_trampoline_offset_; 273 uint32_t portable_resolution_trampoline_offset_; 274 uint32_t portable_to_interpreter_bridge_offset_; 275 uint32_t quick_generic_jni_trampoline_offset_; 276 uint32_t quick_imt_conflict_trampoline_offset_; 277 uint32_t quick_resolution_trampoline_offset_; 278 uint32_t quick_to_interpreter_bridge_offset_; 279 bool compile_pic_; 280 281 // Size of pointers on the target architecture. 282 size_t target_ptr_size_; 283 284 // Bin slot tracking for dirty object packing 285 size_t bin_slot_sizes_[kBinSize]; // Number of bytes in a bin 286 size_t bin_slot_count_[kBinSize]; // Number of objects in a bin 287 288 friend class FixupVisitor; 289 friend class FixupClassVisitor; 290 DISALLOW_COPY_AND_ASSIGN(ImageWriter); 291 }; 292 293 } // namespace art 294 295 #endif // ART_COMPILER_IMAGE_WRITER_H_ 296