/* * 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" namespace art { void StackMapStream::BeginStackMapEntry(uint32_t dex_pc, uint32_t native_pc_offset, uint32_t register_mask, BitVector* sp_mask, uint32_t num_dex_registers, uint8_t inlining_depth) { DCHECK_EQ(0u, current_entry_.dex_pc) << "EndStackMapEntry not called after BeginStackMapEntry"; DCHECK_NE(dex_pc, static_cast(-1)) << "invalid dex_pc"; current_entry_.dex_pc = dex_pc; current_entry_.native_pc_offset = native_pc_offset; current_entry_.register_mask = register_mask; current_entry_.sp_mask = sp_mask; current_entry_.num_dex_registers = num_dex_registers; current_entry_.inlining_depth = inlining_depth; current_entry_.dex_register_locations_start_index = dex_register_locations_.size(); current_entry_.inline_infos_start_index = inline_infos_.size(); current_entry_.dex_register_map_hash = 0; current_entry_.same_dex_register_map_as_ = kNoSameDexMapFound; if (num_dex_registers != 0) { current_entry_.live_dex_registers_mask = ArenaBitVector::Create(allocator_, num_dex_registers, true, kArenaAllocStackMapStream); } else { current_entry_.live_dex_registers_mask = nullptr; } if (sp_mask != nullptr) { stack_mask_max_ = std::max(stack_mask_max_, sp_mask->GetHighestBitSet()); } if (inlining_depth > 0) { number_of_stack_maps_with_inline_info_++; } dex_pc_max_ = std::max(dex_pc_max_, dex_pc); register_mask_max_ = std::max(register_mask_max_, register_mask); current_dex_register_ = 0; } void StackMapStream::EndStackMapEntry() { current_entry_.same_dex_register_map_as_ = FindEntryWithTheSameDexMap(); stack_maps_.push_back(current_entry_); current_entry_ = StackMapEntry(); } void StackMapStream::AddDexRegisterEntry(DexRegisterLocation::Kind kind, int32_t value) { if (kind != DexRegisterLocation::Kind::kNone) { // Ensure we only use non-compressed location kind at this stage. DCHECK(DexRegisterLocation::IsShortLocationKind(kind)) << kind; DexRegisterLocation location(kind, value); // Look for Dex register `location` in the location catalog (using the // companion hash map of locations to indices). Use its index if it // is already in the location catalog. If not, insert it (in the // location catalog and the hash map) and use the newly created index. auto it = location_catalog_entries_indices_.Find(location); if (it != location_catalog_entries_indices_.end()) { // Retrieve the index from the hash map. dex_register_locations_.push_back(it->second); } else { // Create a new entry in the location catalog and the hash map. size_t index = location_catalog_entries_.size(); location_catalog_entries_.push_back(location); dex_register_locations_.push_back(index); location_catalog_entries_indices_.Insert(std::make_pair(location, index)); } if (in_inline_frame_) { // TODO: Support sharing DexRegisterMap across InlineInfo. DCHECK_LT(current_dex_register_, current_inline_info_.num_dex_registers); current_inline_info_.live_dex_registers_mask->SetBit(current_dex_register_); } else { DCHECK_LT(current_dex_register_, current_entry_.num_dex_registers); current_entry_.live_dex_registers_mask->SetBit(current_dex_register_); current_entry_.dex_register_map_hash += (1 << (current_dex_register_ % (sizeof(current_entry_.dex_register_map_hash) * kBitsPerByte))); current_entry_.dex_register_map_hash += static_cast(value); current_entry_.dex_register_map_hash += static_cast(kind); } } current_dex_register_++; } void StackMapStream::BeginInlineInfoEntry(uint32_t method_index, uint32_t dex_pc, InvokeType invoke_type, uint32_t num_dex_registers) { DCHECK(!in_inline_frame_); in_inline_frame_ = true; current_inline_info_.method_index = method_index; current_inline_info_.dex_pc = dex_pc; current_inline_info_.invoke_type = invoke_type; current_inline_info_.num_dex_registers = num_dex_registers; current_inline_info_.dex_register_locations_start_index = dex_register_locations_.size(); if (num_dex_registers != 0) { current_inline_info_.live_dex_registers_mask = ArenaBitVector::Create(allocator_, num_dex_registers, true, kArenaAllocStackMapStream); } else { current_inline_info_.live_dex_registers_mask = nullptr; } current_dex_register_ = 0; } void StackMapStream::EndInlineInfoEntry() { DCHECK(in_inline_frame_); DCHECK_EQ(current_dex_register_, current_inline_info_.num_dex_registers) << "Inline information contains less registers than expected"; in_inline_frame_ = false; inline_infos_.push_back(current_inline_info_); current_inline_info_ = InlineInfoEntry(); } uint32_t StackMapStream::ComputeMaxNativePcOffset() const { uint32_t max_native_pc_offset = 0u; for (const StackMapEntry& entry : stack_maps_) { max_native_pc_offset = std::max(max_native_pc_offset, entry.native_pc_offset); } return max_native_pc_offset; } size_t StackMapStream::PrepareForFillIn() { int stack_mask_number_of_bits = stack_mask_max_ + 1; // Need room for max element too. dex_register_maps_size_ = ComputeDexRegisterMapsSize(); ComputeInlineInfoEncoding(); // needs dex_register_maps_size_. inline_info_size_ = inline_infos_.size() * inline_info_encoding_.GetEntrySize(); uint32_t max_native_pc_offset = ComputeMaxNativePcOffset(); size_t stack_map_size = stack_map_encoding_.SetFromSizes(max_native_pc_offset, dex_pc_max_, dex_register_maps_size_, inline_info_size_, register_mask_max_, stack_mask_number_of_bits); stack_maps_size_ = stack_maps_.size() * stack_map_size; dex_register_location_catalog_size_ = ComputeDexRegisterLocationCatalogSize(); size_t non_header_size = stack_maps_size_ + dex_register_location_catalog_size_ + dex_register_maps_size_ + inline_info_size_; // Prepare the CodeInfo variable-sized encoding. CodeInfoEncoding code_info_encoding; code_info_encoding.non_header_size = non_header_size; code_info_encoding.number_of_stack_maps = stack_maps_.size(); code_info_encoding.stack_map_size_in_bytes = stack_map_size; code_info_encoding.stack_map_encoding = stack_map_encoding_; code_info_encoding.inline_info_encoding = inline_info_encoding_; code_info_encoding.number_of_location_catalog_entries = location_catalog_entries_.size(); code_info_encoding.Compress(&code_info_encoding_); // TODO: Move the catalog at the end. It is currently too expensive at runtime // to compute its size (note that we do not encode that size in the CodeInfo). dex_register_location_catalog_start_ = code_info_encoding_.size() + stack_maps_size_; dex_register_maps_start_ = dex_register_location_catalog_start_ + dex_register_location_catalog_size_; inline_infos_start_ = dex_register_maps_start_ + dex_register_maps_size_; needed_size_ = code_info_encoding_.size() + non_header_size; return needed_size_; } size_t StackMapStream::ComputeDexRegisterLocationCatalogSize() const { size_t size = DexRegisterLocationCatalog::kFixedSize; for (const DexRegisterLocation& dex_register_location : location_catalog_entries_) { size += DexRegisterLocationCatalog::EntrySize(dex_register_location); } return size; } size_t StackMapStream::ComputeDexRegisterMapSize(uint32_t num_dex_registers, const BitVector* live_dex_registers_mask) const { // For num_dex_registers == 0u live_dex_registers_mask may be null. if (num_dex_registers == 0u) { return 0u; // No register map will be emitted. } DCHECK(live_dex_registers_mask != nullptr); // Size of the map in bytes. size_t size = DexRegisterMap::kFixedSize; // Add the live bit mask for the Dex register liveness. size += DexRegisterMap::GetLiveBitMaskSize(num_dex_registers); // Compute the size of the set of live Dex register entries. size_t number_of_live_dex_registers = live_dex_registers_mask->NumSetBits(); size_t map_entries_size_in_bits = DexRegisterMap::SingleEntrySizeInBits(location_catalog_entries_.size()) * number_of_live_dex_registers; size_t map_entries_size_in_bytes = RoundUp(map_entries_size_in_bits, kBitsPerByte) / kBitsPerByte; size += map_entries_size_in_bytes; return size; } size_t StackMapStream::ComputeDexRegisterMapsSize() const { size_t size = 0; size_t inline_info_index = 0; for (const StackMapEntry& entry : stack_maps_) { if (entry.same_dex_register_map_as_ == kNoSameDexMapFound) { size += ComputeDexRegisterMapSize(entry.num_dex_registers, entry.live_dex_registers_mask); } else { // Entries with the same dex map will have the same offset. } for (size_t j = 0; j < entry.inlining_depth; ++j) { InlineInfoEntry inline_entry = inline_infos_[inline_info_index++]; size += ComputeDexRegisterMapSize(inline_entry.num_dex_registers, inline_entry.live_dex_registers_mask); } } return size; } void StackMapStream::ComputeInlineInfoEncoding() { uint32_t method_index_max = 0; uint32_t dex_pc_max = 0; uint32_t invoke_type_max = 0; uint32_t inline_info_index = 0; for (const StackMapEntry& entry : stack_maps_) { for (size_t j = 0; j < entry.inlining_depth; ++j) { InlineInfoEntry inline_entry = inline_infos_[inline_info_index++]; method_index_max = std::max(method_index_max, inline_entry.method_index); dex_pc_max = std::max(dex_pc_max, inline_entry.dex_pc); invoke_type_max = std::max(invoke_type_max, static_cast(inline_entry.invoke_type)); } } DCHECK_EQ(inline_info_index, inline_infos_.size()); inline_info_encoding_.SetFromSizes(method_index_max, dex_pc_max, invoke_type_max, dex_register_maps_size_); } void StackMapStream::FillIn(MemoryRegion region) { DCHECK_EQ(0u, current_entry_.dex_pc) << "EndStackMapEntry not called after BeginStackMapEntry"; DCHECK_NE(0u, needed_size_) << "PrepareForFillIn not called before FillIn"; DCHECK_EQ(region.size(), needed_size_); // Note that the memory region does not have to be zeroed when we JIT code // because we do not use the arena allocator there. // Write the CodeInfo header. region.CopyFrom(0, MemoryRegion(code_info_encoding_.data(), code_info_encoding_.size())); MemoryRegion dex_register_locations_region = region.Subregion( dex_register_maps_start_, dex_register_maps_size_); MemoryRegion inline_infos_region = region.Subregion( inline_infos_start_, inline_info_size_); CodeInfo code_info(region); CodeInfoEncoding encoding = code_info.ExtractEncoding(); DCHECK_EQ(code_info.GetStackMapsSize(encoding), stack_maps_size_); // Set the Dex register location catalog. MemoryRegion dex_register_location_catalog_region = region.Subregion( dex_register_location_catalog_start_, dex_register_location_catalog_size_); DexRegisterLocationCatalog dex_register_location_catalog(dex_register_location_catalog_region); // Offset in `dex_register_location_catalog` where to store the next // register location. size_t location_catalog_offset = DexRegisterLocationCatalog::kFixedSize; for (DexRegisterLocation dex_register_location : location_catalog_entries_) { dex_register_location_catalog.SetRegisterInfo(location_catalog_offset, dex_register_location); location_catalog_offset += DexRegisterLocationCatalog::EntrySize(dex_register_location); } // Ensure we reached the end of the Dex registers location_catalog. DCHECK_EQ(location_catalog_offset, dex_register_location_catalog_region.size()); ArenaBitVector empty_bitmask(allocator_, 0, /* expandable */ false, kArenaAllocStackMapStream); uintptr_t next_dex_register_map_offset = 0; uintptr_t next_inline_info_offset = 0; for (size_t i = 0, e = stack_maps_.size(); i < e; ++i) { StackMap stack_map = code_info.GetStackMapAt(i, encoding); StackMapEntry entry = stack_maps_[i]; stack_map.SetDexPc(stack_map_encoding_, entry.dex_pc); stack_map.SetNativePcOffset(stack_map_encoding_, entry.native_pc_offset); stack_map.SetRegisterMask(stack_map_encoding_, entry.register_mask); size_t number_of_stack_mask_bits = stack_map.GetNumberOfStackMaskBits(stack_map_encoding_); if (entry.sp_mask != nullptr) { for (size_t bit = 0; bit < number_of_stack_mask_bits; bit++) { stack_map.SetStackMaskBit(stack_map_encoding_, bit, entry.sp_mask->IsBitSet(bit)); } } else { // The MemoryRegion does not have to be zeroed, so make sure we clear the bits. for (size_t bit = 0; bit < number_of_stack_mask_bits; bit++) { stack_map.SetStackMaskBit(stack_map_encoding_, bit, false); } } if (entry.num_dex_registers == 0 || (entry.live_dex_registers_mask->NumSetBits() == 0)) { // No dex map available. stack_map.SetDexRegisterMapOffset(stack_map_encoding_, StackMap::kNoDexRegisterMap); } else { // Search for an entry with the same dex map. if (entry.same_dex_register_map_as_ != kNoSameDexMapFound) { // If we have a hit reuse the offset. stack_map.SetDexRegisterMapOffset( stack_map_encoding_, code_info.GetStackMapAt(entry.same_dex_register_map_as_, encoding) .GetDexRegisterMapOffset(stack_map_encoding_)); } else { // New dex registers maps should be added to the stack map. MemoryRegion register_region = dex_register_locations_region.Subregion( next_dex_register_map_offset, ComputeDexRegisterMapSize(entry.num_dex_registers, entry.live_dex_registers_mask)); next_dex_register_map_offset += register_region.size(); DexRegisterMap dex_register_map(register_region); stack_map.SetDexRegisterMapOffset( stack_map_encoding_, register_region.start() - dex_register_locations_region.start()); // Set the dex register location. FillInDexRegisterMap(dex_register_map, entry.num_dex_registers, *entry.live_dex_registers_mask, entry.dex_register_locations_start_index); } } // Set the inlining info. if (entry.inlining_depth != 0) { MemoryRegion inline_region = inline_infos_region.Subregion( next_inline_info_offset, entry.inlining_depth * inline_info_encoding_.GetEntrySize()); next_inline_info_offset += inline_region.size(); InlineInfo inline_info(inline_region); // Currently relative to the dex register map. stack_map.SetInlineDescriptorOffset( stack_map_encoding_, inline_region.start() - dex_register_locations_region.start()); inline_info.SetDepth(inline_info_encoding_, entry.inlining_depth); DCHECK_LE(entry.inline_infos_start_index + entry.inlining_depth, inline_infos_.size()); for (size_t depth = 0; depth < entry.inlining_depth; ++depth) { InlineInfoEntry inline_entry = inline_infos_[depth + entry.inline_infos_start_index]; inline_info.SetMethodIndexAtDepth(inline_info_encoding_, depth, inline_entry.method_index); inline_info.SetDexPcAtDepth(inline_info_encoding_, depth, inline_entry.dex_pc); inline_info.SetInvokeTypeAtDepth(inline_info_encoding_, depth, inline_entry.invoke_type); if (inline_entry.num_dex_registers == 0) { // No dex map available. inline_info.SetDexRegisterMapOffsetAtDepth(inline_info_encoding_, depth, StackMap::kNoDexRegisterMap); DCHECK(inline_entry.live_dex_registers_mask == nullptr); } else { MemoryRegion register_region = dex_register_locations_region.Subregion( next_dex_register_map_offset, ComputeDexRegisterMapSize(inline_entry.num_dex_registers, inline_entry.live_dex_registers_mask)); next_dex_register_map_offset += register_region.size(); DexRegisterMap dex_register_map(register_region); inline_info.SetDexRegisterMapOffsetAtDepth( inline_info_encoding_, depth, register_region.start() - dex_register_locations_region.start()); FillInDexRegisterMap(dex_register_map, inline_entry.num_dex_registers, *inline_entry.live_dex_registers_mask, inline_entry.dex_register_locations_start_index); } } } else { if (inline_info_size_ != 0) { stack_map.SetInlineDescriptorOffset(stack_map_encoding_, StackMap::kNoInlineInfo); } } } // Verify all written data in debug build. if (kIsDebugBuild) { CheckCodeInfo(region); } } void StackMapStream::FillInDexRegisterMap(DexRegisterMap dex_register_map, uint32_t num_dex_registers, const BitVector& live_dex_registers_mask, uint32_t start_index_in_dex_register_locations) const { dex_register_map.SetLiveBitMask(num_dex_registers, live_dex_registers_mask); // Set the dex register location mapping data. size_t number_of_live_dex_registers = live_dex_registers_mask.NumSetBits(); DCHECK_LE(number_of_live_dex_registers, dex_register_locations_.size()); DCHECK_LE(start_index_in_dex_register_locations, dex_register_locations_.size() - number_of_live_dex_registers); for (size_t index_in_dex_register_locations = 0; index_in_dex_register_locations != number_of_live_dex_registers; ++index_in_dex_register_locations) { size_t location_catalog_entry_index = dex_register_locations_[ start_index_in_dex_register_locations + index_in_dex_register_locations]; dex_register_map.SetLocationCatalogEntryIndex( index_in_dex_register_locations, location_catalog_entry_index, num_dex_registers, location_catalog_entries_.size()); } } size_t StackMapStream::FindEntryWithTheSameDexMap() { size_t current_entry_index = stack_maps_.size(); auto entries_it = dex_map_hash_to_stack_map_indices_.find(current_entry_.dex_register_map_hash); if (entries_it == dex_map_hash_to_stack_map_indices_.end()) { // We don't have a perfect hash functions so we need a list to collect all stack maps // which might have the same dex register map. ArenaVector stack_map_indices(allocator_->Adapter(kArenaAllocStackMapStream)); stack_map_indices.push_back(current_entry_index); dex_map_hash_to_stack_map_indices_.Put(current_entry_.dex_register_map_hash, std::move(stack_map_indices)); return kNoSameDexMapFound; } // We might have collisions, so we need to check whether or not we really have a match. for (uint32_t test_entry_index : entries_it->second) { if (HaveTheSameDexMaps(GetStackMap(test_entry_index), current_entry_)) { return test_entry_index; } } entries_it->second.push_back(current_entry_index); return kNoSameDexMapFound; } bool StackMapStream::HaveTheSameDexMaps(const StackMapEntry& a, const StackMapEntry& b) const { if (a.live_dex_registers_mask == nullptr && b.live_dex_registers_mask == nullptr) { return true; } if (a.live_dex_registers_mask == nullptr || b.live_dex_registers_mask == nullptr) { return false; } if (a.num_dex_registers != b.num_dex_registers) { return false; } if (a.num_dex_registers != 0u) { DCHECK(a.live_dex_registers_mask != nullptr); DCHECK(b.live_dex_registers_mask != nullptr); if (!a.live_dex_registers_mask->Equal(b.live_dex_registers_mask)) { return false; } size_t number_of_live_dex_registers = a.live_dex_registers_mask->NumSetBits(); DCHECK_LE(number_of_live_dex_registers, dex_register_locations_.size()); DCHECK_LE(a.dex_register_locations_start_index, dex_register_locations_.size() - number_of_live_dex_registers); DCHECK_LE(b.dex_register_locations_start_index, dex_register_locations_.size() - number_of_live_dex_registers); auto a_begin = dex_register_locations_.begin() + a.dex_register_locations_start_index; auto b_begin = dex_register_locations_.begin() + b.dex_register_locations_start_index; if (!std::equal(a_begin, a_begin + number_of_live_dex_registers, b_begin)) { return false; } } return true; } // Helper for CheckCodeInfo - check that register map has the expected content. void StackMapStream::CheckDexRegisterMap(const CodeInfo& code_info, const DexRegisterMap& dex_register_map, size_t num_dex_registers, BitVector* live_dex_registers_mask, size_t dex_register_locations_index) const { CodeInfoEncoding encoding = code_info.ExtractEncoding(); for (size_t reg = 0; reg < num_dex_registers; reg++) { // Find the location we tried to encode. DexRegisterLocation expected = DexRegisterLocation::None(); if (live_dex_registers_mask->IsBitSet(reg)) { size_t catalog_index = dex_register_locations_[dex_register_locations_index++]; expected = location_catalog_entries_[catalog_index]; } // Compare to the seen location. if (expected.GetKind() == DexRegisterLocation::Kind::kNone) { DCHECK(!dex_register_map.IsValid() || !dex_register_map.IsDexRegisterLive(reg)); } else { DCHECK(dex_register_map.IsDexRegisterLive(reg)); DexRegisterLocation seen = dex_register_map.GetDexRegisterLocation( reg, num_dex_registers, code_info, encoding); DCHECK_EQ(expected.GetKind(), seen.GetKind()); DCHECK_EQ(expected.GetValue(), seen.GetValue()); } } if (num_dex_registers == 0) { DCHECK(!dex_register_map.IsValid()); } } // Check that all StackMapStream inputs are correctly encoded by trying to read them back. void StackMapStream::CheckCodeInfo(MemoryRegion region) const { CodeInfo code_info(region); CodeInfoEncoding encoding = code_info.ExtractEncoding(); DCHECK_EQ(code_info.GetNumberOfStackMaps(encoding), stack_maps_.size()); for (size_t s = 0; s < stack_maps_.size(); ++s) { const StackMap stack_map = code_info.GetStackMapAt(s, encoding); const StackMapEncoding& stack_map_encoding = encoding.stack_map_encoding; StackMapEntry entry = stack_maps_[s]; // Check main stack map fields. DCHECK_EQ(stack_map.GetNativePcOffset(stack_map_encoding), entry.native_pc_offset); DCHECK_EQ(stack_map.GetDexPc(stack_map_encoding), entry.dex_pc); DCHECK_EQ(stack_map.GetRegisterMask(stack_map_encoding), entry.register_mask); size_t num_stack_mask_bits = stack_map.GetNumberOfStackMaskBits(stack_map_encoding); if (entry.sp_mask != nullptr) { DCHECK_GE(num_stack_mask_bits, entry.sp_mask->GetNumberOfBits()); for (size_t b = 0; b < num_stack_mask_bits; b++) { DCHECK_EQ(stack_map.GetStackMaskBit(stack_map_encoding, b), entry.sp_mask->IsBitSet(b)); } } else { for (size_t b = 0; b < num_stack_mask_bits; b++) { DCHECK_EQ(stack_map.GetStackMaskBit(stack_map_encoding, b), 0u); } } CheckDexRegisterMap(code_info, code_info.GetDexRegisterMapOf( stack_map, encoding, entry.num_dex_registers), entry.num_dex_registers, entry.live_dex_registers_mask, entry.dex_register_locations_start_index); // Check inline info. DCHECK_EQ(stack_map.HasInlineInfo(stack_map_encoding), (entry.inlining_depth != 0)); if (entry.inlining_depth != 0) { InlineInfo inline_info = code_info.GetInlineInfoOf(stack_map, encoding); DCHECK_EQ(inline_info.GetDepth(encoding.inline_info_encoding), entry.inlining_depth); for (size_t d = 0; d < entry.inlining_depth; ++d) { size_t inline_info_index = entry.inline_infos_start_index + d; DCHECK_LT(inline_info_index, inline_infos_.size()); InlineInfoEntry inline_entry = inline_infos_[inline_info_index]; DCHECK_EQ(inline_info.GetDexPcAtDepth(encoding.inline_info_encoding, d), inline_entry.dex_pc); DCHECK_EQ(inline_info.GetMethodIndexAtDepth(encoding.inline_info_encoding, d), inline_entry.method_index); DCHECK_EQ(inline_info.GetInvokeTypeAtDepth(encoding.inline_info_encoding, d), inline_entry.invoke_type); CheckDexRegisterMap(code_info, code_info.GetDexRegisterMapAtDepth( d, inline_info, encoding, inline_entry.num_dex_registers), inline_entry.num_dex_registers, inline_entry.live_dex_registers_mask, inline_entry.dex_register_locations_start_index); } } } } } // namespace art