| /* | 
 |  * Copyright (C) 2015 The Android Open Source Project | 
 |  * | 
 |  * Licensed under the Apache License, Version 2.0 (the "License"); | 
 |  * you may not use this file except in compliance with the License. | 
 |  * You may obtain a copy of the License at | 
 |  * | 
 |  *      http://www.apache.org/licenses/LICENSE-2.0 | 
 |  * | 
 |  * Unless required by applicable law or agreed to in writing, software | 
 |  * distributed under the License is distributed on an "AS IS" BASIS, | 
 |  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | 
 |  * See the License for the specific language governing permissions and | 
 |  * limitations under the License. | 
 |  */ | 
 |  | 
 | #include "stack_map_stream.h" | 
 |  | 
 | #include <memory> | 
 |  | 
 | #include "art_method-inl.h" | 
 | #include "base/stl_util.h" | 
 | #include "dex/dex_file_types.h" | 
 | #include "optimizing/optimizing_compiler.h" | 
 | #include "runtime.h" | 
 | #include "scoped_thread_state_change-inl.h" | 
 | #include "stack_map.h" | 
 |  | 
 | namespace art { | 
 |  | 
 | constexpr static bool kVerifyStackMaps = kIsDebugBuild; | 
 |  | 
 | uint32_t StackMapStream::GetStackMapNativePcOffset(size_t i) { | 
 |   return StackMap::UnpackNativePc(stack_maps_[i][StackMap::kPackedNativePc], instruction_set_); | 
 | } | 
 |  | 
 | void StackMapStream::SetStackMapNativePcOffset(size_t i, uint32_t native_pc_offset) { | 
 |   stack_maps_[i][StackMap::kPackedNativePc] = | 
 |       StackMap::PackNativePc(native_pc_offset, instruction_set_); | 
 | } | 
 |  | 
 | void StackMapStream::BeginMethod(size_t frame_size_in_bytes, | 
 |                                  size_t core_spill_mask, | 
 |                                  size_t fp_spill_mask, | 
 |                                  uint32_t num_dex_registers) { | 
 |   DCHECK(!in_method_) << "Mismatched Begin/End calls"; | 
 |   in_method_ = true; | 
 |   DCHECK_EQ(frame_size_in_bytes_, 0u) << "BeginMethod was already called"; | 
 |  | 
 |   frame_size_in_bytes_ = frame_size_in_bytes; | 
 |   core_spill_mask_ = core_spill_mask; | 
 |   fp_spill_mask_ = fp_spill_mask; | 
 |   num_dex_registers_ = num_dex_registers; | 
 | } | 
 |  | 
 | void StackMapStream::EndMethod() { | 
 |   DCHECK(in_method_) << "Mismatched Begin/End calls"; | 
 |   in_method_ = false; | 
 | } | 
 |  | 
 | void StackMapStream::BeginStackMapEntry(uint32_t dex_pc, | 
 |                                         uint32_t native_pc_offset, | 
 |                                         uint32_t register_mask, | 
 |                                         BitVector* stack_mask, | 
 |                                         StackMap::Kind kind) { | 
 |   DCHECK(in_method_) << "Call BeginMethod first"; | 
 |   DCHECK(!in_stack_map_) << "Mismatched Begin/End calls"; | 
 |   in_stack_map_ = true; | 
 |  | 
 |   current_stack_map_ = BitTableBuilder<StackMap>::Entry(); | 
 |   current_stack_map_[StackMap::kKind] = static_cast<uint32_t>(kind); | 
 |   current_stack_map_[StackMap::kPackedNativePc] = | 
 |       StackMap::PackNativePc(native_pc_offset, instruction_set_); | 
 |   current_stack_map_[StackMap::kDexPc] = dex_pc; | 
 |   if (stack_maps_.size() > 0) { | 
 |     // Check that non-catch stack maps are sorted by pc. | 
 |     // Catch stack maps are at the end and may be unordered. | 
 |     if (stack_maps_.back()[StackMap::kKind] == StackMap::Kind::Catch) { | 
 |       DCHECK(current_stack_map_[StackMap::kKind] == StackMap::Kind::Catch); | 
 |     } else if (current_stack_map_[StackMap::kKind] != StackMap::Kind::Catch) { | 
 |       DCHECK_LE(stack_maps_.back()[StackMap::kPackedNativePc], | 
 |                 current_stack_map_[StackMap::kPackedNativePc]); | 
 |     } | 
 |   } | 
 |   if (register_mask != 0) { | 
 |     uint32_t shift = LeastSignificantBit(register_mask); | 
 |     BitTableBuilder<RegisterMask>::Entry entry; | 
 |     entry[RegisterMask::kValue] = register_mask >> shift; | 
 |     entry[RegisterMask::kShift] = shift; | 
 |     current_stack_map_[StackMap::kRegisterMaskIndex] = register_masks_.Dedup(&entry); | 
 |   } | 
 |   // The compiler assumes the bit vector will be read during PrepareForFillIn(), | 
 |   // and it might modify the data before that. Therefore, just store the pointer. | 
 |   // See ClearSpillSlotsFromLoopPhisInStackMap in code_generator.h. | 
 |   lazy_stack_masks_.push_back(stack_mask); | 
 |   current_inline_infos_.clear(); | 
 |   current_dex_registers_.clear(); | 
 |   expected_num_dex_registers_ = num_dex_registers_; | 
 |  | 
 |   if (kVerifyStackMaps) { | 
 |     size_t stack_map_index = stack_maps_.size(); | 
 |     // Create lambda method, which will be executed at the very end to verify data. | 
 |     // Parameters and local variables will be captured(stored) by the lambda "[=]". | 
 |     dchecks_.emplace_back([=](const CodeInfo& code_info) { | 
 |       if (kind == StackMap::Kind::Default || kind == StackMap::Kind::OSR) { | 
 |         StackMap stack_map = code_info.GetStackMapForNativePcOffset(native_pc_offset, | 
 |                                                                     instruction_set_); | 
 |         CHECK_EQ(stack_map.Row(), stack_map_index); | 
 |       } else if (kind == StackMap::Kind::Catch) { | 
 |         StackMap stack_map = code_info.GetCatchStackMapForDexPc(dex_pc); | 
 |         CHECK_EQ(stack_map.Row(), stack_map_index); | 
 |       } | 
 |       StackMap stack_map = code_info.GetStackMapAt(stack_map_index); | 
 |       CHECK_EQ(stack_map.GetNativePcOffset(instruction_set_), native_pc_offset); | 
 |       CHECK_EQ(stack_map.GetKind(), static_cast<uint32_t>(kind)); | 
 |       CHECK_EQ(stack_map.GetDexPc(), dex_pc); | 
 |       CHECK_EQ(code_info.GetRegisterMaskOf(stack_map), register_mask); | 
 |       BitMemoryRegion seen_stack_mask = code_info.GetStackMaskOf(stack_map); | 
 |       CHECK_GE(seen_stack_mask.size_in_bits(), stack_mask ? stack_mask->GetNumberOfBits() : 0); | 
 |       for (size_t b = 0; b < seen_stack_mask.size_in_bits(); b++) { | 
 |         CHECK_EQ(seen_stack_mask.LoadBit(b), stack_mask != nullptr && stack_mask->IsBitSet(b)); | 
 |       } | 
 |     }); | 
 |   } | 
 | } | 
 |  | 
 | void StackMapStream::EndStackMapEntry() { | 
 |   DCHECK(in_stack_map_) << "Mismatched Begin/End calls"; | 
 |   in_stack_map_ = false; | 
 |  | 
 |   // Generate index into the InlineInfo table. | 
 |   size_t inlining_depth = current_inline_infos_.size(); | 
 |   if (!current_inline_infos_.empty()) { | 
 |     current_inline_infos_.back()[InlineInfo::kIsLast] = InlineInfo::kLast; | 
 |     current_stack_map_[StackMap::kInlineInfoIndex] = | 
 |         inline_infos_.Dedup(current_inline_infos_.data(), current_inline_infos_.size()); | 
 |   } | 
 |  | 
 |   // Generate delta-compressed dex register map. | 
 |   size_t num_dex_registers = current_dex_registers_.size(); | 
 |   if (!current_dex_registers_.empty()) { | 
 |     DCHECK_EQ(expected_num_dex_registers_, current_dex_registers_.size()); | 
 |     CreateDexRegisterMap(); | 
 |   } | 
 |  | 
 |   stack_maps_.Add(current_stack_map_); | 
 |  | 
 |   if (kVerifyStackMaps) { | 
 |     size_t stack_map_index = stack_maps_.size() - 1; | 
 |     dchecks_.emplace_back([=](const CodeInfo& code_info) { | 
 |       StackMap stack_map = code_info.GetStackMapAt(stack_map_index); | 
 |       CHECK_EQ(stack_map.HasDexRegisterMap(), (num_dex_registers != 0)); | 
 |       CHECK_EQ(stack_map.HasInlineInfo(), (inlining_depth != 0)); | 
 |       CHECK_EQ(code_info.GetInlineInfosOf(stack_map).size(), inlining_depth); | 
 |     }); | 
 |   } | 
 | } | 
 |  | 
 | void StackMapStream::BeginInlineInfoEntry(ArtMethod* method, | 
 |                                           uint32_t dex_pc, | 
 |                                           uint32_t num_dex_registers, | 
 |                                           const DexFile* outer_dex_file) { | 
 |   DCHECK(in_stack_map_) << "Call BeginStackMapEntry first"; | 
 |   DCHECK(!in_inline_info_) << "Mismatched Begin/End calls"; | 
 |   in_inline_info_ = true; | 
 |   DCHECK_EQ(expected_num_dex_registers_, current_dex_registers_.size()); | 
 |  | 
 |   expected_num_dex_registers_ += num_dex_registers; | 
 |  | 
 |   BitTableBuilder<InlineInfo>::Entry entry; | 
 |   entry[InlineInfo::kIsLast] = InlineInfo::kMore; | 
 |   entry[InlineInfo::kDexPc] = dex_pc; | 
 |   entry[InlineInfo::kNumberOfDexRegisters] = static_cast<uint32_t>(expected_num_dex_registers_); | 
 |   if (EncodeArtMethodInInlineInfo(method)) { | 
 |     entry[InlineInfo::kArtMethodHi] = High32Bits(reinterpret_cast<uintptr_t>(method)); | 
 |     entry[InlineInfo::kArtMethodLo] = Low32Bits(reinterpret_cast<uintptr_t>(method)); | 
 |   } else { | 
 |     if (dex_pc != static_cast<uint32_t>(-1) && kIsDebugBuild) { | 
 |       ScopedObjectAccess soa(Thread::Current()); | 
 |       DCHECK(IsSameDexFile(*outer_dex_file, *method->GetDexFile())); | 
 |     } | 
 |     uint32_t dex_method_index = method->GetDexMethodIndex(); | 
 |     entry[InlineInfo::kMethodInfoIndex] = method_infos_.Dedup({dex_method_index}); | 
 |   } | 
 |   current_inline_infos_.push_back(entry); | 
 |  | 
 |   if (kVerifyStackMaps) { | 
 |     size_t stack_map_index = stack_maps_.size(); | 
 |     size_t depth = current_inline_infos_.size() - 1; | 
 |     dchecks_.emplace_back([=](const CodeInfo& code_info) { | 
 |       StackMap stack_map = code_info.GetStackMapAt(stack_map_index); | 
 |       InlineInfo inline_info = code_info.GetInlineInfosOf(stack_map)[depth]; | 
 |       CHECK_EQ(inline_info.GetDexPc(), dex_pc); | 
 |       bool encode_art_method = EncodeArtMethodInInlineInfo(method); | 
 |       CHECK_EQ(inline_info.EncodesArtMethod(), encode_art_method); | 
 |       if (encode_art_method) { | 
 |         CHECK_EQ(inline_info.GetArtMethod(), method); | 
 |       } else { | 
 |         CHECK_EQ(code_info.GetMethodIndexOf(inline_info), method->GetDexMethodIndex()); | 
 |       } | 
 |     }); | 
 |   } | 
 | } | 
 |  | 
 | void StackMapStream::EndInlineInfoEntry() { | 
 |   DCHECK(in_inline_info_) << "Mismatched Begin/End calls"; | 
 |   in_inline_info_ = false; | 
 |   DCHECK_EQ(expected_num_dex_registers_, current_dex_registers_.size()); | 
 | } | 
 |  | 
 | // Create delta-compressed dex register map based on the current list of DexRegisterLocations. | 
 | // All dex registers for a stack map are concatenated - inlined registers are just appended. | 
 | void StackMapStream::CreateDexRegisterMap() { | 
 |   // These are fields rather than local variables so that we can reuse the reserved memory. | 
 |   temp_dex_register_mask_.ClearAllBits(); | 
 |   temp_dex_register_map_.clear(); | 
 |  | 
 |   // Ensure that the arrays that hold previous state are big enough to be safely indexed below. | 
 |   if (previous_dex_registers_.size() < current_dex_registers_.size()) { | 
 |     previous_dex_registers_.resize(current_dex_registers_.size(), DexRegisterLocation::None()); | 
 |     dex_register_timestamp_.resize(current_dex_registers_.size(), 0u); | 
 |   } | 
 |  | 
 |   // Set bit in the mask for each register that has been changed since the previous stack map. | 
 |   // Modified registers are stored in the catalogue and the catalogue index added to the list. | 
 |   for (size_t i = 0; i < current_dex_registers_.size(); i++) { | 
 |     DexRegisterLocation reg = current_dex_registers_[i]; | 
 |     // Distance is difference between this index and the index of last modification. | 
 |     uint32_t distance = stack_maps_.size() - dex_register_timestamp_[i]; | 
 |     if (previous_dex_registers_[i] != reg || distance > kMaxDexRegisterMapSearchDistance) { | 
 |       BitTableBuilder<DexRegisterInfo>::Entry entry; | 
 |       entry[DexRegisterInfo::kKind] = static_cast<uint32_t>(reg.GetKind()); | 
 |       entry[DexRegisterInfo::kPackedValue] = | 
 |           DexRegisterInfo::PackValue(reg.GetKind(), reg.GetValue()); | 
 |       uint32_t index = reg.IsLive() ? dex_register_catalog_.Dedup(&entry) : kNoValue; | 
 |       temp_dex_register_mask_.SetBit(i); | 
 |       temp_dex_register_map_.push_back({index}); | 
 |       previous_dex_registers_[i] = reg; | 
 |       dex_register_timestamp_[i] = stack_maps_.size(); | 
 |     } | 
 |   } | 
 |  | 
 |   // Set the mask and map for the current StackMap (which includes inlined registers). | 
 |   if (temp_dex_register_mask_.GetNumberOfBits() != 0) { | 
 |     current_stack_map_[StackMap::kDexRegisterMaskIndex] = | 
 |         dex_register_masks_.Dedup(temp_dex_register_mask_.GetRawStorage(), | 
 |                                   temp_dex_register_mask_.GetNumberOfBits()); | 
 |   } | 
 |   if (!current_dex_registers_.empty()) { | 
 |     current_stack_map_[StackMap::kDexRegisterMapIndex] = | 
 |         dex_register_maps_.Dedup(temp_dex_register_map_.data(), | 
 |                                  temp_dex_register_map_.size()); | 
 |   } | 
 |  | 
 |   if (kVerifyStackMaps) { | 
 |     size_t stack_map_index = stack_maps_.size(); | 
 |     // We need to make copy of the current registers for later (when the check is run). | 
 |     auto expected_dex_registers = std::make_shared<dchecked_vector<DexRegisterLocation>>( | 
 |         current_dex_registers_.begin(), current_dex_registers_.end()); | 
 |     dchecks_.emplace_back([=](const CodeInfo& code_info) { | 
 |       StackMap stack_map = code_info.GetStackMapAt(stack_map_index); | 
 |       uint32_t expected_reg = 0; | 
 |       for (DexRegisterLocation reg : code_info.GetDexRegisterMapOf(stack_map)) { | 
 |         CHECK_EQ((*expected_dex_registers)[expected_reg++], reg); | 
 |       } | 
 |       for (InlineInfo inline_info : code_info.GetInlineInfosOf(stack_map)) { | 
 |         DexRegisterMap map = code_info.GetInlineDexRegisterMapOf(stack_map, inline_info); | 
 |         for (DexRegisterLocation reg : map) { | 
 |           CHECK_EQ((*expected_dex_registers)[expected_reg++], reg); | 
 |         } | 
 |       } | 
 |       CHECK_EQ(expected_reg, expected_dex_registers->size()); | 
 |     }); | 
 |   } | 
 | } | 
 |  | 
 | template<typename Writer, typename Builder> | 
 | ALWAYS_INLINE static void EncodeTable(Writer& out, const Builder& bit_table) { | 
 |   out.WriteBit(false);  // Is not deduped. | 
 |   bit_table.Encode(out); | 
 | } | 
 |  | 
 | size_t StackMapStream::PrepareForFillIn() { | 
 |   DCHECK_EQ(out_.size(), 0u); | 
 |  | 
 |   // Read the stack masks now. The compiler might have updated them. | 
 |   for (size_t i = 0; i < lazy_stack_masks_.size(); i++) { | 
 |     BitVector* stack_mask = lazy_stack_masks_[i]; | 
 |     if (stack_mask != nullptr && stack_mask->GetNumberOfBits() != 0) { | 
 |       stack_maps_[i][StackMap::kStackMaskIndex] = | 
 |         stack_masks_.Dedup(stack_mask->GetRawStorage(), stack_mask->GetNumberOfBits()); | 
 |     } | 
 |   } | 
 |  | 
 |   EncodeUnsignedLeb128(&out_, frame_size_in_bytes_); | 
 |   EncodeUnsignedLeb128(&out_, core_spill_mask_); | 
 |   EncodeUnsignedLeb128(&out_, fp_spill_mask_); | 
 |   EncodeUnsignedLeb128(&out_, num_dex_registers_); | 
 |   BitMemoryWriter<ScopedArenaVector<uint8_t>> out(&out_, out_.size() * kBitsPerByte); | 
 |   EncodeTable(out, stack_maps_); | 
 |   EncodeTable(out, inline_infos_); | 
 |   EncodeTable(out, method_infos_); | 
 |   EncodeTable(out, register_masks_); | 
 |   EncodeTable(out, stack_masks_); | 
 |   EncodeTable(out, dex_register_masks_); | 
 |   EncodeTable(out, dex_register_maps_); | 
 |   EncodeTable(out, dex_register_catalog_); | 
 |  | 
 |   return out_.size(); | 
 | } | 
 |  | 
 | void StackMapStream::FillInCodeInfo(MemoryRegion region) { | 
 |   DCHECK(in_stack_map_ == false) << "Mismatched Begin/End calls"; | 
 |   DCHECK(in_inline_info_ == false) << "Mismatched Begin/End calls"; | 
 |   DCHECK_NE(0u, out_.size()) << "PrepareForFillIn not called before FillIn"; | 
 |   DCHECK_EQ(region.size(), out_.size()); | 
 |  | 
 |   region.CopyFromVector(0, out_); | 
 |  | 
 |   // Verify that we can load the CodeInfo and check some essentials. | 
 |   CodeInfo code_info(region); | 
 |   CHECK_EQ(code_info.Size(), out_.size()); | 
 |   CHECK_EQ(code_info.GetNumberOfStackMaps(), stack_maps_.size()); | 
 |  | 
 |   // Verify all written data (usually only in debug builds). | 
 |   if (kVerifyStackMaps) { | 
 |     for (const auto& dcheck : dchecks_) { | 
 |       dcheck(code_info); | 
 |     } | 
 |   } | 
 | } | 
 |  | 
 | }  // namespace art |