| /* |
| * Copyright (C) 2014 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. |
| */ |
| |
| #ifndef ART_RUNTIME_STACK_MAP_H_ |
| #define ART_RUNTIME_STACK_MAP_H_ |
| |
| #include "base/bit_vector.h" |
| #include "base/bit_utils.h" |
| #include "memory_region.h" |
| |
| namespace art { |
| |
| // Size of a frame slot, in bytes. This constant is a signed value, |
| // to please the compiler in arithmetic operations involving int32_t |
| // (signed) values. |
| static constexpr ssize_t kFrameSlotSize = 4; |
| |
| // Size of Dex virtual registers. |
| static constexpr size_t kVRegSize = 4; |
| |
| class CodeInfo; |
| |
| /** |
| * Classes in the following file are wrapper on stack map information backed |
| * by a MemoryRegion. As such they read and write to the region, they don't have |
| * their own fields. |
| */ |
| |
| // Dex register location container used by DexRegisterMap and StackMapStream. |
| class DexRegisterLocation { |
| public: |
| /* |
| * The location kind used to populate the Dex register information in a |
| * StackMapStream can either be: |
| * - kNone: the register has no location yet, meaning it has not been set; |
| * - kConstant: value holds the constant; |
| * - kStack: value holds the stack offset; |
| * - kRegister: value holds the physical register number; |
| * - kFpuRegister: value holds the physical register number. |
| * |
| * In addition, DexRegisterMap also uses these values: |
| * - kInStackLargeOffset: value holds a "large" stack offset (greater than |
| * or equal to 128 bytes); |
| * - kConstantLargeValue: value holds a "large" constant (lower than 0, or |
| * or greater than or equal to 32). |
| */ |
| enum class Kind : uint8_t { |
| // Short location kinds, for entries fitting on one byte (3 bits |
| // for the kind, 5 bits for the value) in a DexRegisterMap. |
| kNone = 0, // 0b000 |
| kInStack = 1, // 0b001 |
| kInRegister = 2, // 0b010 |
| kInFpuRegister = 3, // 0b011 |
| kConstant = 4, // 0b100 |
| |
| // Large location kinds, requiring a 5-byte encoding (1 byte for the |
| // kind, 4 bytes for the value). |
| |
| // Stack location at a large offset, meaning that the offset value |
| // divided by the stack frame slot size (4 bytes) cannot fit on a |
| // 5-bit unsigned integer (i.e., this offset value is greater than |
| // or equal to 2^5 * 4 = 128 bytes). |
| kInStackLargeOffset = 5, // 0b101 |
| |
| // Large constant, that cannot fit on a 5-bit signed integer (i.e., |
| // lower than 0, or greater than or equal to 2^5 = 32). |
| kConstantLargeValue = 6, // 0b110 |
| |
| kLastLocationKind = kConstantLargeValue |
| }; |
| |
| static_assert( |
| sizeof(Kind) == 1u, |
| "art::DexRegisterLocation::Kind has a size different from one byte."); |
| |
| static const char* PrettyDescriptor(Kind kind) { |
| switch (kind) { |
| case Kind::kNone: |
| return "none"; |
| case Kind::kInStack: |
| return "in stack"; |
| case Kind::kInRegister: |
| return "in register"; |
| case Kind::kInFpuRegister: |
| return "in fpu register"; |
| case Kind::kConstant: |
| return "as constant"; |
| case Kind::kInStackLargeOffset: |
| return "in stack (large offset)"; |
| case Kind::kConstantLargeValue: |
| return "as constant (large value)"; |
| default: |
| UNREACHABLE(); |
| } |
| } |
| |
| static bool IsShortLocationKind(Kind kind) { |
| switch (kind) { |
| case Kind::kNone: |
| case Kind::kInStack: |
| case Kind::kInRegister: |
| case Kind::kInFpuRegister: |
| case Kind::kConstant: |
| return true; |
| |
| case Kind::kInStackLargeOffset: |
| case Kind::kConstantLargeValue: |
| return false; |
| |
| default: |
| UNREACHABLE(); |
| } |
| } |
| |
| // Convert `kind` to a "surface" kind, i.e. one that doesn't include |
| // any value with a "large" qualifier. |
| // TODO: Introduce another enum type for the surface kind? |
| static Kind ConvertToSurfaceKind(Kind kind) { |
| switch (kind) { |
| case Kind::kNone: |
| case Kind::kInStack: |
| case Kind::kInRegister: |
| case Kind::kInFpuRegister: |
| case Kind::kConstant: |
| return kind; |
| |
| case Kind::kInStackLargeOffset: |
| return Kind::kInStack; |
| |
| case Kind::kConstantLargeValue: |
| return Kind::kConstant; |
| |
| default: |
| UNREACHABLE(); |
| } |
| } |
| |
| // Required by art::StackMapStream::LocationCatalogEntriesIndices. |
| DexRegisterLocation() : kind_(Kind::kNone), value_(0) {} |
| |
| DexRegisterLocation(Kind kind, int32_t value) : kind_(kind), value_(value) {} |
| |
| static DexRegisterLocation None() { |
| return DexRegisterLocation(Kind::kNone, 0); |
| } |
| |
| // Get the "surface" kind of the location, i.e., the one that doesn't |
| // include any value with a "large" qualifier. |
| Kind GetKind() const { |
| return ConvertToSurfaceKind(kind_); |
| } |
| |
| // Get the value of the location. |
| int32_t GetValue() const { return value_; } |
| |
| // Get the actual kind of the location. |
| Kind GetInternalKind() const { return kind_; } |
| |
| bool operator==(DexRegisterLocation other) const { |
| return kind_ == other.kind_ && value_ == other.value_; |
| } |
| |
| bool operator!=(DexRegisterLocation other) const { |
| return !(*this == other); |
| } |
| |
| private: |
| Kind kind_; |
| int32_t value_; |
| |
| friend class DexRegisterLocationHashFn; |
| }; |
| |
| /** |
| * Store information on unique Dex register locations used in a method. |
| * The information is of the form: |
| * [DexRegisterLocation+]. |
| * DexRegisterLocations are either 1- or 5-byte wide (see art::DexRegisterLocation::Kind). |
| */ |
| class DexRegisterLocationCatalog { |
| public: |
| explicit DexRegisterLocationCatalog(MemoryRegion region) : region_(region) {} |
| |
| // Short (compressed) location, fitting on one byte. |
| typedef uint8_t ShortLocation; |
| |
| void SetRegisterInfo(size_t offset, const DexRegisterLocation& dex_register_location) { |
| DexRegisterLocation::Kind kind = ComputeCompressedKind(dex_register_location); |
| int32_t value = dex_register_location.GetValue(); |
| if (DexRegisterLocation::IsShortLocationKind(kind)) { |
| // Short location. Compress the kind and the value as a single byte. |
| if (kind == DexRegisterLocation::Kind::kInStack) { |
| // Instead of storing stack offsets expressed in bytes for |
| // short stack locations, store slot offsets. A stack offset |
| // is a multiple of 4 (kFrameSlotSize). This means that by |
| // dividing it by 4, we can fit values from the [0, 128) |
| // interval in a short stack location, and not just values |
| // from the [0, 32) interval. |
| DCHECK_EQ(value % kFrameSlotSize, 0); |
| value /= kFrameSlotSize; |
| } |
| DCHECK(IsShortValue(value)) << value; |
| region_.StoreUnaligned<ShortLocation>(offset, MakeShortLocation(kind, value)); |
| } else { |
| // Large location. Write the location on one byte and the value |
| // on 4 bytes. |
| DCHECK(!IsShortValue(value)) << value; |
| if (kind == DexRegisterLocation::Kind::kInStackLargeOffset) { |
| // Also divide large stack offsets by 4 for the sake of consistency. |
| DCHECK_EQ(value % kFrameSlotSize, 0); |
| value /= kFrameSlotSize; |
| } |
| // Data can be unaligned as the written Dex register locations can |
| // either be 1-byte or 5-byte wide. Use |
| // art::MemoryRegion::StoreUnaligned instead of |
| // art::MemoryRegion::Store to prevent unligned word accesses on ARM. |
| region_.StoreUnaligned<DexRegisterLocation::Kind>(offset, kind); |
| region_.StoreUnaligned<int32_t>(offset + sizeof(DexRegisterLocation::Kind), value); |
| } |
| } |
| |
| // Find the offset of the location catalog entry number `location_catalog_entry_index`. |
| size_t FindLocationOffset(size_t location_catalog_entry_index) const { |
| size_t offset = kFixedSize; |
| // Skip the first `location_catalog_entry_index - 1` entries. |
| for (uint16_t i = 0; i < location_catalog_entry_index; ++i) { |
| // Read the first next byte and inspect its first 3 bits to decide |
| // whether it is a short or a large location. |
| DexRegisterLocation::Kind kind = ExtractKindAtOffset(offset); |
| if (DexRegisterLocation::IsShortLocationKind(kind)) { |
| // Short location. Skip the current byte. |
| offset += SingleShortEntrySize(); |
| } else { |
| // Large location. Skip the 5 next bytes. |
| offset += SingleLargeEntrySize(); |
| } |
| } |
| return offset; |
| } |
| |
| // Get the internal kind of entry at `location_catalog_entry_index`. |
| DexRegisterLocation::Kind GetLocationInternalKind(size_t location_catalog_entry_index) const { |
| if (location_catalog_entry_index == kNoLocationEntryIndex) { |
| return DexRegisterLocation::Kind::kNone; |
| } |
| return ExtractKindAtOffset(FindLocationOffset(location_catalog_entry_index)); |
| } |
| |
| // Get the (surface) kind and value of entry at `location_catalog_entry_index`. |
| DexRegisterLocation GetDexRegisterLocation(size_t location_catalog_entry_index) const { |
| if (location_catalog_entry_index == kNoLocationEntryIndex) { |
| return DexRegisterLocation::None(); |
| } |
| size_t offset = FindLocationOffset(location_catalog_entry_index); |
| // Read the first byte and inspect its first 3 bits to get the location. |
| ShortLocation first_byte = region_.LoadUnaligned<ShortLocation>(offset); |
| DexRegisterLocation::Kind kind = ExtractKindFromShortLocation(first_byte); |
| if (DexRegisterLocation::IsShortLocationKind(kind)) { |
| // Short location. Extract the value from the remaining 5 bits. |
| int32_t value = ExtractValueFromShortLocation(first_byte); |
| if (kind == DexRegisterLocation::Kind::kInStack) { |
| // Convert the stack slot (short) offset to a byte offset value. |
| value *= kFrameSlotSize; |
| } |
| return DexRegisterLocation(kind, value); |
| } else { |
| // Large location. Read the four next bytes to get the value. |
| int32_t value = region_.LoadUnaligned<int32_t>(offset + sizeof(DexRegisterLocation::Kind)); |
| if (kind == DexRegisterLocation::Kind::kInStackLargeOffset) { |
| // Convert the stack slot (large) offset to a byte offset value. |
| value *= kFrameSlotSize; |
| } |
| return DexRegisterLocation(kind, value); |
| } |
| } |
| |
| // Compute the compressed kind of `location`. |
| static DexRegisterLocation::Kind ComputeCompressedKind(const DexRegisterLocation& location) { |
| switch (location.GetInternalKind()) { |
| case DexRegisterLocation::Kind::kNone: |
| DCHECK_EQ(location.GetValue(), 0); |
| return DexRegisterLocation::Kind::kNone; |
| |
| case DexRegisterLocation::Kind::kInRegister: |
| DCHECK_GE(location.GetValue(), 0); |
| DCHECK_LT(location.GetValue(), 1 << kValueBits); |
| return DexRegisterLocation::Kind::kInRegister; |
| |
| case DexRegisterLocation::Kind::kInFpuRegister: |
| DCHECK_GE(location.GetValue(), 0); |
| DCHECK_LT(location.GetValue(), 1 << kValueBits); |
| return DexRegisterLocation::Kind::kInFpuRegister; |
| |
| case DexRegisterLocation::Kind::kInStack: |
| return IsShortStackOffsetValue(location.GetValue()) |
| ? DexRegisterLocation::Kind::kInStack |
| : DexRegisterLocation::Kind::kInStackLargeOffset; |
| |
| case DexRegisterLocation::Kind::kConstant: |
| return IsShortConstantValue(location.GetValue()) |
| ? DexRegisterLocation::Kind::kConstant |
| : DexRegisterLocation::Kind::kConstantLargeValue; |
| |
| default: |
| LOG(FATAL) << "Unexpected location kind" |
| << DexRegisterLocation::PrettyDescriptor(location.GetInternalKind()); |
| UNREACHABLE(); |
| } |
| } |
| |
| // Can `location` be turned into a short location? |
| static bool CanBeEncodedAsShortLocation(const DexRegisterLocation& location) { |
| switch (location.GetInternalKind()) { |
| case DexRegisterLocation::Kind::kNone: |
| case DexRegisterLocation::Kind::kInRegister: |
| case DexRegisterLocation::Kind::kInFpuRegister: |
| return true; |
| |
| case DexRegisterLocation::Kind::kInStack: |
| return IsShortStackOffsetValue(location.GetValue()); |
| |
| case DexRegisterLocation::Kind::kConstant: |
| return IsShortConstantValue(location.GetValue()); |
| |
| default: |
| UNREACHABLE(); |
| } |
| } |
| |
| static size_t EntrySize(const DexRegisterLocation& location) { |
| return CanBeEncodedAsShortLocation(location) ? SingleShortEntrySize() : SingleLargeEntrySize(); |
| } |
| |
| static size_t SingleShortEntrySize() { |
| return sizeof(ShortLocation); |
| } |
| |
| static size_t SingleLargeEntrySize() { |
| return sizeof(DexRegisterLocation::Kind) + sizeof(int32_t); |
| } |
| |
| size_t Size() const { |
| return region_.size(); |
| } |
| |
| void Dump(std::ostream& os, const CodeInfo& code_info); |
| |
| // Special (invalid) Dex register location catalog entry index meaning |
| // that there is no location for a given Dex register (i.e., it is |
| // mapped to a DexRegisterLocation::Kind::kNone location). |
| static constexpr size_t kNoLocationEntryIndex = -1; |
| |
| private: |
| static constexpr int kFixedSize = 0; |
| |
| // Width of the kind "field" in a short location, in bits. |
| static constexpr size_t kKindBits = 3; |
| // Width of the value "field" in a short location, in bits. |
| static constexpr size_t kValueBits = 5; |
| |
| static constexpr uint8_t kKindMask = (1 << kKindBits) - 1; |
| static constexpr int32_t kValueMask = (1 << kValueBits) - 1; |
| static constexpr size_t kKindOffset = 0; |
| static constexpr size_t kValueOffset = kKindBits; |
| |
| static bool IsShortStackOffsetValue(int32_t value) { |
| DCHECK_EQ(value % kFrameSlotSize, 0); |
| return IsShortValue(value / kFrameSlotSize); |
| } |
| |
| static bool IsShortConstantValue(int32_t value) { |
| return IsShortValue(value); |
| } |
| |
| static bool IsShortValue(int32_t value) { |
| return IsUint<kValueBits>(value); |
| } |
| |
| static ShortLocation MakeShortLocation(DexRegisterLocation::Kind kind, int32_t value) { |
| uint8_t kind_integer_value = static_cast<uint8_t>(kind); |
| DCHECK(IsUint<kKindBits>(kind_integer_value)) << kind_integer_value; |
| DCHECK(IsShortValue(value)) << value; |
| return (kind_integer_value & kKindMask) << kKindOffset |
| | (value & kValueMask) << kValueOffset; |
| } |
| |
| static DexRegisterLocation::Kind ExtractKindFromShortLocation(ShortLocation location) { |
| uint8_t kind = (location >> kKindOffset) & kKindMask; |
| DCHECK_LE(kind, static_cast<uint8_t>(DexRegisterLocation::Kind::kLastLocationKind)); |
| // We do not encode kNone locations in the stack map. |
| DCHECK_NE(kind, static_cast<uint8_t>(DexRegisterLocation::Kind::kNone)); |
| return static_cast<DexRegisterLocation::Kind>(kind); |
| } |
| |
| static int32_t ExtractValueFromShortLocation(ShortLocation location) { |
| return (location >> kValueOffset) & kValueMask; |
| } |
| |
| // Extract a location kind from the byte at position `offset`. |
| DexRegisterLocation::Kind ExtractKindAtOffset(size_t offset) const { |
| ShortLocation first_byte = region_.LoadUnaligned<ShortLocation>(offset); |
| return ExtractKindFromShortLocation(first_byte); |
| } |
| |
| MemoryRegion region_; |
| |
| friend class CodeInfo; |
| friend class StackMapStream; |
| }; |
| |
| /* Information on Dex register locations for a specific PC, mapping a |
| * stack map's Dex register to a location entry in a DexRegisterLocationCatalog. |
| * The information is of the form: |
| * [live_bit_mask, entries*] |
| * where entries are concatenated unsigned integer values encoded on a number |
| * of bits (fixed per DexRegisterMap instances of a CodeInfo object) depending |
| * on the number of entries in the Dex register location catalog |
| * (see DexRegisterMap::SingleEntrySizeInBits). The map is 1-byte aligned. |
| */ |
| class DexRegisterMap { |
| public: |
| explicit DexRegisterMap(MemoryRegion region) : region_(region) {} |
| |
| // Get the surface kind of Dex register `dex_register_number`. |
| DexRegisterLocation::Kind GetLocationKind(uint16_t dex_register_number, |
| uint16_t number_of_dex_registers, |
| const CodeInfo& code_info) const { |
| return DexRegisterLocation::ConvertToSurfaceKind( |
| GetLocationInternalKind(dex_register_number, number_of_dex_registers, code_info)); |
| } |
| |
| // Get the internal kind of Dex register `dex_register_number`. |
| DexRegisterLocation::Kind GetLocationInternalKind(uint16_t dex_register_number, |
| uint16_t number_of_dex_registers, |
| const CodeInfo& code_info) const; |
| |
| // Get the Dex register location `dex_register_number`. |
| DexRegisterLocation GetDexRegisterLocation(uint16_t dex_register_number, |
| uint16_t number_of_dex_registers, |
| const CodeInfo& code_info) const; |
| |
| int32_t GetStackOffsetInBytes(uint16_t dex_register_number, |
| uint16_t number_of_dex_registers, |
| const CodeInfo& code_info) const { |
| DexRegisterLocation location = |
| GetDexRegisterLocation(dex_register_number, number_of_dex_registers, code_info); |
| DCHECK(location.GetKind() == DexRegisterLocation::Kind::kInStack); |
| // GetDexRegisterLocation returns the offset in bytes. |
| return location.GetValue(); |
| } |
| |
| int32_t GetConstant(uint16_t dex_register_number, |
| uint16_t number_of_dex_registers, |
| const CodeInfo& code_info) const { |
| DexRegisterLocation location = |
| GetDexRegisterLocation(dex_register_number, number_of_dex_registers, code_info); |
| DCHECK(location.GetKind() == DexRegisterLocation::Kind::kConstant) |
| << DexRegisterLocation::PrettyDescriptor(location.GetKind()); |
| return location.GetValue(); |
| } |
| |
| int32_t GetMachineRegister(uint16_t dex_register_number, |
| uint16_t number_of_dex_registers, |
| const CodeInfo& code_info) const { |
| DexRegisterLocation location = |
| GetDexRegisterLocation(dex_register_number, number_of_dex_registers, code_info); |
| DCHECK(location.GetInternalKind() == DexRegisterLocation::Kind::kInRegister |
| || location.GetInternalKind() == DexRegisterLocation::Kind::kInFpuRegister) |
| << DexRegisterLocation::PrettyDescriptor(location.GetInternalKind()); |
| return location.GetValue(); |
| } |
| |
| // Get the index of the entry in the Dex register location catalog |
| // corresponding to `dex_register_number`. |
| size_t GetLocationCatalogEntryIndex(uint16_t dex_register_number, |
| uint16_t number_of_dex_registers, |
| size_t number_of_location_catalog_entries) const { |
| if (!IsDexRegisterLive(dex_register_number)) { |
| return DexRegisterLocationCatalog::kNoLocationEntryIndex; |
| } |
| |
| if (number_of_location_catalog_entries == 1) { |
| // We do not allocate space for location maps in the case of a |
| // single-entry location catalog, as it is useless. The only valid |
| // entry index is 0; |
| return 0; |
| } |
| |
| // The bit offset of the beginning of the map locations. |
| size_t map_locations_offset_in_bits = |
| GetLocationMappingDataOffset(number_of_dex_registers) * kBitsPerByte; |
| size_t index_in_dex_register_map = GetIndexInDexRegisterMap(dex_register_number); |
| DCHECK_LT(index_in_dex_register_map, GetNumberOfLiveDexRegisters(number_of_dex_registers)); |
| // The bit size of an entry. |
| size_t map_entry_size_in_bits = SingleEntrySizeInBits(number_of_location_catalog_entries); |
| // The bit offset where `index_in_dex_register_map` is located. |
| size_t entry_offset_in_bits = |
| map_locations_offset_in_bits + index_in_dex_register_map * map_entry_size_in_bits; |
| size_t location_catalog_entry_index = |
| region_.LoadBits(entry_offset_in_bits, map_entry_size_in_bits); |
| DCHECK_LT(location_catalog_entry_index, number_of_location_catalog_entries); |
| return location_catalog_entry_index; |
| } |
| |
| // Map entry at `index_in_dex_register_map` to `location_catalog_entry_index`. |
| void SetLocationCatalogEntryIndex(size_t index_in_dex_register_map, |
| size_t location_catalog_entry_index, |
| uint16_t number_of_dex_registers, |
| size_t number_of_location_catalog_entries) { |
| DCHECK_LT(index_in_dex_register_map, GetNumberOfLiveDexRegisters(number_of_dex_registers)); |
| DCHECK_LT(location_catalog_entry_index, number_of_location_catalog_entries); |
| |
| if (number_of_location_catalog_entries == 1) { |
| // We do not allocate space for location maps in the case of a |
| // single-entry location catalog, as it is useless. |
| return; |
| } |
| |
| // The bit offset of the beginning of the map locations. |
| size_t map_locations_offset_in_bits = |
| GetLocationMappingDataOffset(number_of_dex_registers) * kBitsPerByte; |
| // The bit size of an entry. |
| size_t map_entry_size_in_bits = SingleEntrySizeInBits(number_of_location_catalog_entries); |
| // The bit offset where `index_in_dex_register_map` is located. |
| size_t entry_offset_in_bits = |
| map_locations_offset_in_bits + index_in_dex_register_map * map_entry_size_in_bits; |
| region_.StoreBits(entry_offset_in_bits, location_catalog_entry_index, map_entry_size_in_bits); |
| } |
| |
| void SetLiveBitMask(uint16_t number_of_dex_registers, |
| const BitVector& live_dex_registers_mask) { |
| size_t live_bit_mask_offset_in_bits = GetLiveBitMaskOffset() * kBitsPerByte; |
| for (uint16_t i = 0; i < number_of_dex_registers; ++i) { |
| region_.StoreBit(live_bit_mask_offset_in_bits + i, live_dex_registers_mask.IsBitSet(i)); |
| } |
| } |
| |
| bool IsDexRegisterLive(uint16_t dex_register_number) const { |
| size_t live_bit_mask_offset_in_bits = GetLiveBitMaskOffset() * kBitsPerByte; |
| return region_.LoadBit(live_bit_mask_offset_in_bits + dex_register_number); |
| } |
| |
| size_t GetNumberOfLiveDexRegisters(uint16_t number_of_dex_registers) const { |
| size_t number_of_live_dex_registers = 0; |
| for (size_t i = 0; i < number_of_dex_registers; ++i) { |
| if (IsDexRegisterLive(i)) { |
| ++number_of_live_dex_registers; |
| } |
| } |
| return number_of_live_dex_registers; |
| } |
| |
| static size_t GetLiveBitMaskOffset() { |
| return kFixedSize; |
| } |
| |
| // Compute the size of the live register bit mask (in bytes), for a |
| // method having `number_of_dex_registers` Dex registers. |
| static size_t GetLiveBitMaskSize(uint16_t number_of_dex_registers) { |
| return RoundUp(number_of_dex_registers, kBitsPerByte) / kBitsPerByte; |
| } |
| |
| static size_t GetLocationMappingDataOffset(uint16_t number_of_dex_registers) { |
| return GetLiveBitMaskOffset() + GetLiveBitMaskSize(number_of_dex_registers); |
| } |
| |
| size_t GetLocationMappingDataSize(uint16_t number_of_dex_registers, |
| size_t number_of_location_catalog_entries) const { |
| size_t location_mapping_data_size_in_bits = |
| GetNumberOfLiveDexRegisters(number_of_dex_registers) |
| * SingleEntrySizeInBits(number_of_location_catalog_entries); |
| return RoundUp(location_mapping_data_size_in_bits, kBitsPerByte) / kBitsPerByte; |
| } |
| |
| // Return the size of a map entry in bits. Note that if |
| // `number_of_location_catalog_entries` equals 1, this function returns 0, |
| // which is fine, as there is no need to allocate a map for a |
| // single-entry location catalog; the only valid location catalog entry index |
| // for a live register in this case is 0 and there is no need to |
| // store it. |
| static size_t SingleEntrySizeInBits(size_t number_of_location_catalog_entries) { |
| // Handle the case of 0, as we cannot pass 0 to art::WhichPowerOf2. |
| return number_of_location_catalog_entries == 0 |
| ? 0u |
| : WhichPowerOf2(RoundUpToPowerOfTwo(number_of_location_catalog_entries)); |
| } |
| |
| // Return the size of the DexRegisterMap object, in bytes. |
| size_t Size() const { |
| return region_.size(); |
| } |
| |
| void Dump(std::ostream& o, const CodeInfo& code_info, uint16_t number_of_dex_registers) const; |
| |
| private: |
| // Return the index in the Dex register map corresponding to the Dex |
| // register number `dex_register_number`. |
| size_t GetIndexInDexRegisterMap(uint16_t dex_register_number) const { |
| if (!IsDexRegisterLive(dex_register_number)) { |
| return kInvalidIndexInDexRegisterMap; |
| } |
| return GetNumberOfLiveDexRegisters(dex_register_number); |
| } |
| |
| // Special (invalid) Dex register map entry index meaning that there |
| // is no index in the map for a given Dex register (i.e., it must |
| // have been mapped to a DexRegisterLocation::Kind::kNone location). |
| static constexpr size_t kInvalidIndexInDexRegisterMap = -1; |
| |
| static constexpr int kFixedSize = 0; |
| |
| MemoryRegion region_; |
| |
| friend class CodeInfo; |
| friend class StackMapStream; |
| }; |
| |
| /** |
| * A Stack Map holds compilation information for a specific PC necessary for: |
| * - Mapping it to a dex PC, |
| * - Knowing which stack entries are objects, |
| * - Knowing which registers hold objects, |
| * - Knowing the inlining information, |
| * - Knowing the values of dex registers. |
| * |
| * The information is of the form: |
| * [dex_pc, native_pc_offset, dex_register_map_offset, inlining_info_offset, register_mask, |
| * stack_mask]. |
| */ |
| class StackMap { |
| public: |
| explicit StackMap(MemoryRegion region) : region_(region) {} |
| StackMap() {} |
| |
| bool IsValid() const { return region_.pointer() != nullptr; } |
| |
| uint32_t GetDexPc(const CodeInfo& info) const; |
| |
| void SetDexPc(const CodeInfo& info, uint32_t dex_pc); |
| |
| uint32_t GetNativePcOffset(const CodeInfo& info) const; |
| |
| void SetNativePcOffset(const CodeInfo& info, uint32_t native_pc_offset); |
| |
| uint32_t GetDexRegisterMapOffset(const CodeInfo& info) const; |
| |
| void SetDexRegisterMapOffset(const CodeInfo& info, uint32_t offset); |
| |
| uint32_t GetInlineDescriptorOffset(const CodeInfo& info) const; |
| |
| void SetInlineDescriptorOffset(const CodeInfo& info, uint32_t offset); |
| |
| uint32_t GetRegisterMask(const CodeInfo& info) const; |
| |
| void SetRegisterMask(const CodeInfo& info, uint32_t mask); |
| |
| MemoryRegion GetStackMask(const CodeInfo& info) const; |
| |
| void SetStackMask(const CodeInfo& info, const BitVector& sp_map) { |
| MemoryRegion region = GetStackMask(info); |
| for (size_t i = 0; i < region.size_in_bits(); i++) { |
| region.StoreBit(i, sp_map.IsBitSet(i)); |
| } |
| } |
| |
| bool HasDexRegisterMap(const CodeInfo& info) const { |
| return GetDexRegisterMapOffset(info) != kNoDexRegisterMap; |
| } |
| |
| bool HasInlineInfo(const CodeInfo& info) const { |
| return GetInlineDescriptorOffset(info) != kNoInlineInfo; |
| } |
| |
| bool Equals(const StackMap& other) const { |
| return region_.pointer() == other.region_.pointer() |
| && region_.size() == other.region_.size(); |
| } |
| |
| static size_t ComputeStackMapSize(size_t stack_mask_size, |
| size_t inline_info_size, |
| size_t dex_register_map_size, |
| size_t dex_pc_max, |
| size_t native_pc_max, |
| size_t register_mask_max); |
| |
| // Special (invalid) offset for the DexRegisterMapOffset field meaning |
| // that there is no Dex register map for this stack map. |
| static constexpr uint32_t kNoDexRegisterMap = -1; |
| |
| // Special (invalid) offset for the InlineDescriptorOffset field meaning |
| // that there is no inline info for this stack map. |
| static constexpr uint32_t kNoInlineInfo = -1; |
| |
| private: |
| static size_t ComputeStackMapSizeInternal(size_t stack_mask_size, |
| size_t number_of_bytes_for_inline_info, |
| size_t number_of_bytes_for_dex_map, |
| size_t number_of_bytes_for_dex_pc, |
| size_t number_of_bytes_for_native_pc, |
| size_t number_of_bytes_for_register_mask); |
| |
| // TODO: Instead of plain types such as "uint32_t", introduce |
| // typedefs (and document the memory layout of StackMap). |
| static constexpr int kRegisterMaskOffset = 0; |
| static constexpr int kFixedSize = 0; |
| |
| MemoryRegion region_; |
| |
| friend class CodeInfo; |
| friend class StackMapStream; |
| }; |
| |
| /** |
| * Inline information for a specific PC. The information is of the form: |
| * [inlining_depth, [dex_pc, method_index, dex_register_map_offset]+] |
| */ |
| class InlineInfo { |
| public: |
| explicit InlineInfo(MemoryRegion region) : region_(region) {} |
| |
| uint8_t GetDepth() const { |
| return region_.LoadUnaligned<uint8_t>(kDepthOffset); |
| } |
| |
| void SetDepth(uint8_t depth) { |
| region_.StoreUnaligned<uint8_t>(kDepthOffset, depth); |
| } |
| |
| uint32_t GetMethodIndexAtDepth(uint8_t depth) const { |
| return region_.LoadUnaligned<uint32_t>( |
| kFixedSize + depth * SingleEntrySize() + kMethodIndexOffset); |
| } |
| |
| void SetMethodIndexAtDepth(uint8_t depth, uint32_t index) { |
| region_.StoreUnaligned<uint32_t>( |
| kFixedSize + depth * SingleEntrySize() + kMethodIndexOffset, index); |
| } |
| |
| uint32_t GetDexPcAtDepth(uint8_t depth) const { |
| return region_.LoadUnaligned<uint32_t>( |
| kFixedSize + depth * SingleEntrySize() + kDexPcOffset); |
| } |
| |
| void SetDexPcAtDepth(uint8_t depth, uint32_t dex_pc) { |
| region_.StoreUnaligned<uint32_t>( |
| kFixedSize + depth * SingleEntrySize() + kDexPcOffset, dex_pc); |
| } |
| |
| uint8_t GetInvokeTypeAtDepth(uint8_t depth) const { |
| return region_.LoadUnaligned<uint8_t>( |
| kFixedSize + depth * SingleEntrySize() + kInvokeTypeOffset); |
| } |
| |
| void SetInvokeTypeAtDepth(uint8_t depth, uint8_t invoke_type) { |
| region_.StoreUnaligned<uint8_t>( |
| kFixedSize + depth * SingleEntrySize() + kInvokeTypeOffset, invoke_type); |
| } |
| |
| uint32_t GetDexRegisterMapOffsetAtDepth(uint8_t depth) const { |
| return region_.LoadUnaligned<uint32_t>( |
| kFixedSize + depth * SingleEntrySize() + kDexRegisterMapOffset); |
| } |
| |
| void SetDexRegisterMapOffsetAtDepth(uint8_t depth, uint32_t offset) { |
| region_.StoreUnaligned<uint32_t>( |
| kFixedSize + depth * SingleEntrySize() + kDexRegisterMapOffset, offset); |
| } |
| |
| bool HasDexRegisterMapAtDepth(uint8_t depth) const { |
| return GetDexRegisterMapOffsetAtDepth(depth) != StackMap::kNoDexRegisterMap; |
| } |
| |
| static size_t SingleEntrySize() { |
| return kFixedEntrySize; |
| } |
| |
| void Dump(std::ostream& os, const CodeInfo& info, uint16_t* number_of_dex_registers) const; |
| |
| private: |
| // TODO: Instead of plain types such as "uint8_t", introduce |
| // typedefs (and document the memory layout of InlineInfo). |
| static constexpr int kDepthOffset = 0; |
| static constexpr int kFixedSize = kDepthOffset + sizeof(uint8_t); |
| |
| static constexpr int kMethodIndexOffset = 0; |
| static constexpr int kDexPcOffset = kMethodIndexOffset + sizeof(uint32_t); |
| static constexpr int kInvokeTypeOffset = kDexPcOffset + sizeof(uint32_t); |
| static constexpr int kDexRegisterMapOffset = kInvokeTypeOffset + sizeof(uint8_t); |
| static constexpr int kFixedEntrySize = kDexRegisterMapOffset + sizeof(uint32_t); |
| |
| MemoryRegion region_; |
| |
| friend class CodeInfo; |
| friend class StackMap; |
| friend class StackMapStream; |
| }; |
| |
| /** |
| * Wrapper around all compiler information collected for a method. |
| * The information is of the form: |
| * [overall_size, number_of_location_catalog_entries, number_of_stack_maps, stack_mask_size, |
| * DexRegisterLocationCatalog+, StackMap+, DexRegisterMap+, InlineInfo*]. |
| */ |
| class CodeInfo { |
| public: |
| explicit CodeInfo(MemoryRegion region) : region_(region) {} |
| |
| explicit CodeInfo(const void* data) { |
| uint32_t size = reinterpret_cast<const uint32_t*>(data)[0]; |
| region_ = MemoryRegion(const_cast<void*>(data), size); |
| } |
| |
| static size_t EncodingSizeInBytes(size_t max_element) { |
| DCHECK(IsUint<32>(max_element)); |
| return (max_element == 0) ? 0 |
| : IsUint<8>(max_element) ? 1 |
| : IsUint<16>(max_element) ? 2 |
| : IsUint<24>(max_element) ? 3 |
| : 4; |
| } |
| |
| void SetEncoding(size_t inline_info_size, |
| size_t dex_register_map_size, |
| size_t dex_pc_max, |
| size_t native_pc_max, |
| size_t register_mask_max) { |
| if (inline_info_size != 0) { |
| region_.StoreBit(kHasInlineInfoBitOffset, 1); |
| // + 1 to also encode kNoInlineInfo: if an inline info offset |
| // is at 0xFF, we want to overflow to a larger encoding, because it will |
| // conflict with kNoInlineInfo. |
| // The offset is relative to the dex register map. TODO: Change this. |
| SetEncodingAt(kInlineInfoBitOffset, |
| EncodingSizeInBytes(dex_register_map_size + inline_info_size + 1)); |
| } else { |
| region_.StoreBit(kHasInlineInfoBitOffset, 0); |
| SetEncodingAt(kInlineInfoBitOffset, 0); |
| } |
| // + 1 to also encode kNoDexRegisterMap: if a dex register map offset |
| // is at 0xFF, we want to overflow to a larger encoding, because it will |
| // conflict with kNoDexRegisterMap. |
| SetEncodingAt(kDexRegisterMapBitOffset, EncodingSizeInBytes(dex_register_map_size + 1)); |
| SetEncodingAt(kDexPcBitOffset, EncodingSizeInBytes(dex_pc_max)); |
| SetEncodingAt(kNativePcBitOffset, EncodingSizeInBytes(native_pc_max)); |
| SetEncodingAt(kRegisterMaskBitOffset, EncodingSizeInBytes(register_mask_max)); |
| } |
| |
| void SetEncodingAt(size_t bit_offset, size_t number_of_bytes) { |
| // We encode the number of bytes needed for writing a value on 3 bits, |
| // for values that we know are maximum 32bits. |
| region_.StoreBit(bit_offset, (number_of_bytes & 1)); |
| region_.StoreBit(bit_offset + 1, (number_of_bytes & 2)); |
| region_.StoreBit(bit_offset + 2, (number_of_bytes & 4)); |
| } |
| |
| size_t GetNumberOfBytesForEncoding(size_t bit_offset) const { |
| return region_.LoadBit(bit_offset) |
| + (region_.LoadBit(bit_offset + 1) << 1) |
| + (region_.LoadBit(bit_offset + 2) << 2); |
| } |
| |
| bool HasInlineInfo() const { |
| return region_.LoadBit(kHasInlineInfoBitOffset); |
| } |
| |
| size_t NumberOfBytesForInlineInfo() const { |
| return GetNumberOfBytesForEncoding(kInlineInfoBitOffset); |
| } |
| |
| size_t NumberOfBytesForDexRegisterMap() const { |
| return GetNumberOfBytesForEncoding(kDexRegisterMapBitOffset); |
| } |
| |
| size_t NumberOfBytesForRegisterMask() const { |
| return GetNumberOfBytesForEncoding(kRegisterMaskBitOffset); |
| } |
| |
| size_t NumberOfBytesForNativePc() const { |
| return GetNumberOfBytesForEncoding(kNativePcBitOffset); |
| } |
| |
| size_t NumberOfBytesForDexPc() const { |
| return GetNumberOfBytesForEncoding(kDexPcBitOffset); |
| } |
| |
| size_t ComputeStackMapRegisterMaskOffset() const { |
| return StackMap::kRegisterMaskOffset; |
| } |
| |
| size_t ComputeStackMapStackMaskOffset() const { |
| return ComputeStackMapRegisterMaskOffset() |
| + (NumberOfBytesForRegisterMask() * sizeof(uint8_t)); |
| } |
| |
| size_t ComputeStackMapDexPcOffset() const { |
| return ComputeStackMapStackMaskOffset() + GetStackMaskSize(); |
| } |
| |
| size_t ComputeStackMapNativePcOffset() const { |
| return ComputeStackMapDexPcOffset() |
| + (NumberOfBytesForDexPc() * sizeof(uint8_t)); |
| } |
| |
| size_t ComputeStackMapDexRegisterMapOffset() const { |
| return ComputeStackMapNativePcOffset() |
| + (NumberOfBytesForNativePc() * sizeof(uint8_t)); |
| } |
| |
| size_t ComputeStackMapInlineInfoOffset() const { |
| CHECK(HasInlineInfo()); |
| return ComputeStackMapDexRegisterMapOffset() |
| + (NumberOfBytesForDexRegisterMap() * sizeof(uint8_t)); |
| } |
| |
| DexRegisterLocationCatalog GetDexRegisterLocationCatalog() const { |
| return DexRegisterLocationCatalog(region_.Subregion( |
| GetDexRegisterLocationCatalogOffset(), |
| GetDexRegisterLocationCatalogSize())); |
| } |
| |
| StackMap GetStackMapAt(size_t i) const { |
| size_t size = StackMapSize(); |
| return StackMap(GetStackMaps().Subregion(i * size, size)); |
| } |
| |
| uint32_t GetOverallSize() const { |
| return region_.LoadUnaligned<uint32_t>(kOverallSizeOffset); |
| } |
| |
| void SetOverallSize(uint32_t size) { |
| region_.StoreUnaligned<uint32_t>(kOverallSizeOffset, size); |
| } |
| |
| uint32_t GetNumberOfDexRegisterLocationCatalogEntries() const { |
| return region_.LoadUnaligned<uint32_t>(kNumberOfDexRegisterLocationCatalogEntriesOffset); |
| } |
| |
| void SetNumberOfDexRegisterLocationCatalogEntries(uint32_t num_entries) { |
| region_.StoreUnaligned<uint32_t>(kNumberOfDexRegisterLocationCatalogEntriesOffset, num_entries); |
| } |
| |
| uint32_t GetDexRegisterLocationCatalogSize() const { |
| return ComputeDexRegisterLocationCatalogSize(GetDexRegisterLocationCatalogOffset(), |
| GetNumberOfDexRegisterLocationCatalogEntries()); |
| } |
| |
| uint32_t GetStackMaskSize() const { |
| return region_.LoadUnaligned<uint32_t>(kStackMaskSizeOffset); |
| } |
| |
| void SetStackMaskSize(uint32_t size) { |
| region_.StoreUnaligned<uint32_t>(kStackMaskSizeOffset, size); |
| } |
| |
| size_t GetNumberOfStackMaps() const { |
| return region_.LoadUnaligned<uint32_t>(kNumberOfStackMapsOffset); |
| } |
| |
| void SetNumberOfStackMaps(uint32_t number_of_stack_maps) { |
| region_.StoreUnaligned<uint32_t>(kNumberOfStackMapsOffset, number_of_stack_maps); |
| } |
| |
| // Get the size of one stack map of this CodeInfo object, in bytes. |
| // All stack maps of a CodeInfo have the same size. |
| size_t StackMapSize() const { |
| return StackMap::ComputeStackMapSizeInternal(GetStackMaskSize(), |
| NumberOfBytesForInlineInfo(), |
| NumberOfBytesForDexRegisterMap(), |
| NumberOfBytesForDexPc(), |
| NumberOfBytesForNativePc(), |
| NumberOfBytesForRegisterMask()); |
| } |
| |
| // Get the size all the stack maps of this CodeInfo object, in bytes. |
| size_t GetStackMapsSize() const { |
| return StackMapSize() * GetNumberOfStackMaps(); |
| } |
| |
| uint32_t GetDexRegisterLocationCatalogOffset() const { |
| return GetStackMapsOffset() + GetStackMapsSize(); |
| } |
| |
| size_t GetDexRegisterMapsOffset() const { |
| return GetDexRegisterLocationCatalogOffset() + GetDexRegisterLocationCatalogSize(); |
| } |
| |
| uint32_t GetStackMapsOffset() const { |
| return kFixedSize; |
| } |
| |
| DexRegisterMap GetDexRegisterMapOf(StackMap stack_map, uint32_t number_of_dex_registers) const { |
| DCHECK(stack_map.HasDexRegisterMap(*this)); |
| uint32_t offset = GetDexRegisterMapsOffset() + stack_map.GetDexRegisterMapOffset(*this); |
| size_t size = ComputeDexRegisterMapSizeOf(offset, number_of_dex_registers); |
| return DexRegisterMap(region_.Subregion(offset, size)); |
| } |
| |
| // Return the `DexRegisterMap` pointed by `inline_info` at depth `depth`. |
| DexRegisterMap GetDexRegisterMapAtDepth(uint8_t depth, |
| InlineInfo inline_info, |
| uint32_t number_of_dex_registers) const { |
| DCHECK(inline_info.HasDexRegisterMapAtDepth(depth)); |
| uint32_t offset = |
| GetDexRegisterMapsOffset() + inline_info.GetDexRegisterMapOffsetAtDepth(depth); |
| size_t size = ComputeDexRegisterMapSizeOf(offset, number_of_dex_registers); |
| return DexRegisterMap(region_.Subregion(offset, size)); |
| } |
| |
| InlineInfo GetInlineInfoOf(StackMap stack_map) const { |
| DCHECK(stack_map.HasInlineInfo(*this)); |
| uint32_t offset = stack_map.GetInlineDescriptorOffset(*this) + GetDexRegisterMapsOffset(); |
| uint8_t depth = region_.LoadUnaligned<uint8_t>(offset); |
| return InlineInfo(region_.Subregion(offset, |
| InlineInfo::kFixedSize + depth * InlineInfo::SingleEntrySize())); |
| } |
| |
| StackMap GetStackMapForDexPc(uint32_t dex_pc) const { |
| for (size_t i = 0, e = GetNumberOfStackMaps(); i < e; ++i) { |
| StackMap stack_map = GetStackMapAt(i); |
| if (stack_map.GetDexPc(*this) == dex_pc) { |
| return stack_map; |
| } |
| } |
| return StackMap(); |
| } |
| |
| StackMap GetStackMapForNativePcOffset(uint32_t native_pc_offset) const { |
| // TODO: stack maps are sorted by native pc, we can do a binary search. |
| for (size_t i = 0, e = GetNumberOfStackMaps(); i < e; ++i) { |
| StackMap stack_map = GetStackMapAt(i); |
| if (stack_map.GetNativePcOffset(*this) == native_pc_offset) { |
| return stack_map; |
| } |
| } |
| return StackMap(); |
| } |
| |
| // Dump this CodeInfo object on `os`. If `dump_stack_maps` is true, |
| // also dump the stack maps and the associated Dex register maps. |
| void Dump(std::ostream& os, uint16_t number_of_dex_registers, bool dump_stack_maps) const; |
| |
| // Dump stack map number `stack_map_num` as well as associated data on `os`, |
| // such as Dex register locations. |
| void DumpStackMap(std::ostream& os, size_t stack_map_num, uint16_t number_of_dex_registers) const; |
| // Dump the header of stack map number `stack_map_num` on `os`, without |
| // associated data. |
| void DumpStackMapHeader(std::ostream& os, size_t stack_map_num) const; |
| |
| private: |
| // TODO: Instead of plain types such as "uint32_t", introduce |
| // typedefs (and document the memory layout of CodeInfo). |
| static constexpr int kOverallSizeOffset = 0; |
| static constexpr int kEncodingInfoOffset = kOverallSizeOffset + sizeof(uint32_t); |
| static constexpr int kNumberOfDexRegisterLocationCatalogEntriesOffset = |
| kEncodingInfoOffset + sizeof(uint16_t); |
| static constexpr int kNumberOfStackMapsOffset = |
| kNumberOfDexRegisterLocationCatalogEntriesOffset + sizeof(uint32_t); |
| static constexpr int kStackMaskSizeOffset = kNumberOfStackMapsOffset + sizeof(uint32_t); |
| static constexpr int kFixedSize = kStackMaskSizeOffset + sizeof(uint32_t); |
| |
| static constexpr int kHasInlineInfoBitOffset = (kEncodingInfoOffset * kBitsPerByte); |
| static constexpr int kInlineInfoBitOffset = kHasInlineInfoBitOffset + 1; |
| static constexpr int kDexRegisterMapBitOffset = kInlineInfoBitOffset + 3; |
| static constexpr int kDexPcBitOffset = kDexRegisterMapBitOffset + 3; |
| static constexpr int kNativePcBitOffset = kDexPcBitOffset + 3; |
| static constexpr int kRegisterMaskBitOffset = kNativePcBitOffset + 3; |
| |
| MemoryRegion GetStackMaps() const { |
| return region_.size() == 0 |
| ? MemoryRegion() |
| : region_.Subregion(GetStackMapsOffset(), GetStackMapsSize()); |
| } |
| |
| // Compute the size of the Dex register map associated to the stack map at |
| // `dex_register_map_offset_in_code_info`. |
| size_t ComputeDexRegisterMapSizeOf(uint32_t dex_register_map_offset_in_code_info, |
| uint16_t number_of_dex_registers) const { |
| // Offset where the actual mapping data starts within art::DexRegisterMap. |
| size_t location_mapping_data_offset_in_dex_register_map = |
| DexRegisterMap::GetLocationMappingDataOffset(number_of_dex_registers); |
| // Create a temporary art::DexRegisterMap to be able to call |
| // art::DexRegisterMap::GetNumberOfLiveDexRegisters and |
| DexRegisterMap dex_register_map_without_locations( |
| MemoryRegion(region_.Subregion(dex_register_map_offset_in_code_info, |
| location_mapping_data_offset_in_dex_register_map))); |
| size_t number_of_live_dex_registers = |
| dex_register_map_without_locations.GetNumberOfLiveDexRegisters(number_of_dex_registers); |
| size_t location_mapping_data_size_in_bits = |
| DexRegisterMap::SingleEntrySizeInBits(GetNumberOfDexRegisterLocationCatalogEntries()) |
| * number_of_live_dex_registers; |
| size_t location_mapping_data_size_in_bytes = |
| RoundUp(location_mapping_data_size_in_bits, kBitsPerByte) / kBitsPerByte; |
| size_t dex_register_map_size = |
| location_mapping_data_offset_in_dex_register_map + location_mapping_data_size_in_bytes; |
| return dex_register_map_size; |
| } |
| |
| // Compute the size of a Dex register location catalog starting at offset `origin` |
| // in `region_` and containing `number_of_dex_locations` entries. |
| size_t ComputeDexRegisterLocationCatalogSize(uint32_t origin, |
| uint32_t number_of_dex_locations) const { |
| // TODO: Ideally, we would like to use art::DexRegisterLocationCatalog::Size or |
| // art::DexRegisterLocationCatalog::FindLocationOffset, but the |
| // DexRegisterLocationCatalog is not yet built. Try to factor common code. |
| size_t offset = origin + DexRegisterLocationCatalog::kFixedSize; |
| |
| // Skip the first `number_of_dex_locations - 1` entries. |
| for (uint16_t i = 0; i < number_of_dex_locations; ++i) { |
| // Read the first next byte and inspect its first 3 bits to decide |
| // whether it is a short or a large location. |
| DexRegisterLocationCatalog::ShortLocation first_byte = |
| region_.LoadUnaligned<DexRegisterLocationCatalog::ShortLocation>(offset); |
| DexRegisterLocation::Kind kind = |
| DexRegisterLocationCatalog::ExtractKindFromShortLocation(first_byte); |
| if (DexRegisterLocation::IsShortLocationKind(kind)) { |
| // Short location. Skip the current byte. |
| offset += DexRegisterLocationCatalog::SingleShortEntrySize(); |
| } else { |
| // Large location. Skip the 5 next bytes. |
| offset += DexRegisterLocationCatalog::SingleLargeEntrySize(); |
| } |
| } |
| size_t size = offset - origin; |
| return size; |
| } |
| |
| MemoryRegion region_; |
| friend class StackMapStream; |
| }; |
| |
| } // namespace art |
| |
| #endif // ART_RUNTIME_STACK_MAP_H_ |