runtime/stack_map.h - platform/art - Git at Google

 /*
  * 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 "memory_region.h"
 #include "utils.h"

 namespace art {

 /**
  * 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.
  */

 /**
  * Inline information for a specific PC. The information is of the form:
  * [inlining_depth, [method_dex reference]+]
  */
 class InlineInfo {
  public:
   explicit InlineInfo(MemoryRegion region) : region_(region) {}

   uint8_t GetDepth() const {
     return region_.Load<uint8_t>(kDepthOffset);
   }

   void SetDepth(uint8_t depth) {
     region_.Store<uint8_t>(kDepthOffset, depth);
   }

   uint32_t GetMethodReferenceIndexAtDepth(uint8_t depth) const {
     return region_.Load<uint32_t>(kFixedSize + depth * SingleEntrySize());
   }

   void SetMethodReferenceIndexAtDepth(uint8_t depth, uint32_t index) {
     region_.Store<uint32_t>(kFixedSize + depth * SingleEntrySize(), index);
   }

   static size_t SingleEntrySize() {
     return sizeof(uint32_t);
   }

  private:
   static constexpr int kDepthOffset = 0;
   static constexpr int kFixedSize = kDepthOffset + sizeof(uint8_t);

   static constexpr uint32_t kNoInlineInfo = -1;

   MemoryRegion region_;

   friend class CodeInfo;
   friend class StackMap;
   friend class StackMapStream;
 };

 /**
  * Information on dex register values for a specific PC. The information is
  * of the form:
  * [location_kind, register_value]+.
  *
  * The location_kind for a Dex register can either be:
  * - Constant: register_value holds the constant,
  * - Stack: register_value holds the stack offset,
  * - Register: register_value holds the physical register number.
  * - None: the register has no location yet, meaning it has not been set.
  */
 class DexRegisterMap {
  public:
   explicit DexRegisterMap(MemoryRegion region) : region_(region) {}

   enum LocationKind {
     kNone,
     kInStack,
     kInRegister,
     kInFpuRegister,
     kConstant
   };

   LocationKind GetLocationKind(uint16_t register_index) const {
     return region_.Load<LocationKind>(
         kFixedSize + register_index * SingleEntrySize());
   }

   void SetRegisterInfo(uint16_t register_index, LocationKind kind, int32_t value) {
     size_t entry = kFixedSize + register_index * SingleEntrySize();
     region_.Store<LocationKind>(entry, kind);
     region_.Store<int32_t>(entry + sizeof(LocationKind), value);
   }

   int32_t GetValue(uint16_t register_index) const {
     return region_.Load<int32_t>(
         kFixedSize + sizeof(LocationKind) + register_index * SingleEntrySize());
   }

   static size_t SingleEntrySize() {
     return sizeof(LocationKind) + sizeof(int32_t);
   }

  private:
   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].
  *
  * Note that register_mask is fixed size, but stack_mask is variable size, depending on the
  * stack size of a method.
  */
 class StackMap {
  public:
   explicit StackMap(MemoryRegion region) : region_(region) {}

   uint32_t GetDexPc() const {
     return region_.Load<uint32_t>(kDexPcOffset);
   }

   void SetDexPc(uint32_t dex_pc) {
     region_.Store<uint32_t>(kDexPcOffset, dex_pc);
   }

   uint32_t GetNativePcOffset() const {
     return region_.Load<uint32_t>(kNativePcOffsetOffset);
   }

   void SetNativePcOffset(uint32_t native_pc_offset) {
     return region_.Store<uint32_t>(kNativePcOffsetOffset, native_pc_offset);
   }

   uint32_t GetDexRegisterMapOffset() const {
     return region_.Load<uint32_t>(kDexRegisterMapOffsetOffset);
   }

   void SetDexRegisterMapOffset(uint32_t offset) {
     return region_.Store<uint32_t>(kDexRegisterMapOffsetOffset, offset);
   }

   uint32_t GetInlineDescriptorOffset() const {
     return region_.Load<uint32_t>(kInlineDescriptorOffsetOffset);
   }

   void SetInlineDescriptorOffset(uint32_t offset) {
     return region_.Store<uint32_t>(kInlineDescriptorOffsetOffset, offset);
   }

   uint32_t GetRegisterMask() const {
     return region_.Load<uint32_t>(kRegisterMaskOffset);
   }

   void SetRegisterMask(uint32_t mask) {
     region_.Store<uint32_t>(kRegisterMaskOffset, mask);
   }

   MemoryRegion GetStackMask() const {
     return region_.Subregion(kStackMaskOffset, StackMaskSize());
   }

   void SetStackMask(const BitVector& sp_map) {
     MemoryRegion region = GetStackMask();
     for (size_t i = 0; i < region.size_in_bits(); i++) {
       region.StoreBit(i, sp_map.IsBitSet(i));
     }
   }

   bool HasInlineInfo() const {
     return GetInlineDescriptorOffset() != InlineInfo::kNoInlineInfo;
   }

   bool Equals(const StackMap& other) {
     return region_.pointer() == other.region_.pointer()
        && region_.size() == other.region_.size();
   }

   static size_t ComputeAlignedStackMapSize(size_t stack_mask_size) {
     // On ARM, the stack maps must be 4-byte aligned.
     return RoundUp(StackMap::kFixedSize + stack_mask_size, 4);
   }

  private:
   static constexpr int kDexPcOffset = 0;
   static constexpr int kNativePcOffsetOffset = kDexPcOffset + sizeof(uint32_t);
   static constexpr int kDexRegisterMapOffsetOffset = kNativePcOffsetOffset + sizeof(uint32_t);
   static constexpr int kInlineDescriptorOffsetOffset =
       kDexRegisterMapOffsetOffset + sizeof(uint32_t);
   static constexpr int kRegisterMaskOffset = kInlineDescriptorOffsetOffset + sizeof(uint32_t);
   static constexpr int kFixedSize = kRegisterMaskOffset + sizeof(uint32_t);
   static constexpr int kStackMaskOffset = kFixedSize;

   size_t StackMaskSize() const { return region_.size() - kFixedSize; }

   MemoryRegion region_;

   friend class CodeInfo;
   friend class StackMapStream;
 };


 /**
  * Wrapper around all compiler information collected for a method.
  * The information is of the form:
  * [overall_size, number_of_stack_maps, stack_mask_size, StackMap+, DexRegisterInfo+, 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);
   }

   StackMap GetStackMapAt(size_t i) const {
     size_t size = StackMapSize();
     return StackMap(GetStackMaps().Subregion(i * size, size));
   }

   uint32_t GetOverallSize() const {
     return region_.Load<uint32_t>(kOverallSizeOffset);
   }

   void SetOverallSize(uint32_t size) {
     region_.Store<uint32_t>(kOverallSizeOffset, size);
   }

   uint32_t GetStackMaskSize() const {
     return region_.Load<uint32_t>(kStackMaskSizeOffset);
   }

   void SetStackMaskSize(uint32_t size) {
     region_.Store<uint32_t>(kStackMaskSizeOffset, size);
   }

   size_t GetNumberOfStackMaps() const {
     return region_.Load<uint32_t>(kNumberOfStackMapsOffset);
   }

   void SetNumberOfStackMaps(uint32_t number_of_stack_maps) {
     region_.Store<uint32_t>(kNumberOfStackMapsOffset, number_of_stack_maps);
   }

   size_t StackMapSize() const {
     return StackMap::ComputeAlignedStackMapSize(GetStackMaskSize());
   }

   DexRegisterMap GetDexRegisterMapOf(StackMap stack_map, uint32_t number_of_dex_registers) {
     uint32_t offset = stack_map.GetDexRegisterMapOffset();
     return DexRegisterMap(region_.Subregion(offset,
         DexRegisterMap::kFixedSize + number_of_dex_registers * DexRegisterMap::SingleEntrySize()));
   }

   InlineInfo GetInlineInfoOf(StackMap stack_map) {
     uint32_t offset = stack_map.GetInlineDescriptorOffset();
     uint8_t depth = region_.Load<uint8_t>(offset);
     return InlineInfo(region_.Subregion(offset,
         InlineInfo::kFixedSize + depth * InlineInfo::SingleEntrySize()));
   }

   StackMap GetStackMapForDexPc(uint32_t dex_pc) {
     for (size_t i = 0, e = GetNumberOfStackMaps(); i < e; ++i) {
       StackMap stack_map = GetStackMapAt(i);
       if (stack_map.GetDexPc() == dex_pc) {
         return stack_map;
       }
     }
     LOG(FATAL) << "Unreachable";
     UNREACHABLE();
   }

   StackMap GetStackMapForNativePcOffset(uint32_t native_pc_offset) {
     // 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() == native_pc_offset) {
         return stack_map;
       }
     }
     LOG(FATAL) << "Unreachable";
     UNREACHABLE();
   }

  private:
   static constexpr int kOverallSizeOffset = 0;
   static constexpr int kNumberOfStackMapsOffset = kOverallSizeOffset + sizeof(uint32_t);
   static constexpr int kStackMaskSizeOffset = kNumberOfStackMapsOffset + sizeof(uint32_t);
   static constexpr int kFixedSize = kStackMaskSizeOffset + sizeof(uint32_t);

   MemoryRegion GetStackMaps() const {
     return region_.size() == 0
         ? MemoryRegion()
         : region_.Subregion(kFixedSize, StackMapSize() * GetNumberOfStackMaps());
   }

   MemoryRegion region_;
   friend class StackMapStream;
 };

 }  // namespace art

 #endif  // ART_RUNTIME_STACK_MAP_H_
	/*
	* 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 "memory_region.h"
	#include "utils.h"

	namespace art {

	/**
	* 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.
	*/

	/**
	* Inline information for a specific PC. The information is of the form:
	* [inlining_depth, [method_dex reference]+]
	*/
	class InlineInfo {
	public:
	explicit InlineInfo(MemoryRegion region) : region_(region) {}

	uint8_t GetDepth() const {
	return region_.Load<uint8_t>(kDepthOffset);
	}

	void SetDepth(uint8_t depth) {
	region_.Store<uint8_t>(kDepthOffset, depth);
	}

	uint32_t GetMethodReferenceIndexAtDepth(uint8_t depth) const {
	return region_.Load<uint32_t>(kFixedSize + depth * SingleEntrySize());
	}

	void SetMethodReferenceIndexAtDepth(uint8_t depth, uint32_t index) {
	region_.Store<uint32_t>(kFixedSize + depth * SingleEntrySize(), index);
	}

	static size_t SingleEntrySize() {
	return sizeof(uint32_t);
	}

	private:
	static constexpr int kDepthOffset = 0;
	static constexpr int kFixedSize = kDepthOffset + sizeof(uint8_t);

	static constexpr uint32_t kNoInlineInfo = -1;

	MemoryRegion region_;

	friend class CodeInfo;
	friend class StackMap;
	friend class StackMapStream;
	};

	/**
	* Information on dex register values for a specific PC. The information is
	* of the form:
	* [location_kind, register_value]+.
	*
	* The location_kind for a Dex register can either be:
	* - Constant: register_value holds the constant,
	* - Stack: register_value holds the stack offset,
	* - Register: register_value holds the physical register number.
	* - None: the register has no location yet, meaning it has not been set.
	*/
	class DexRegisterMap {
	public:
	explicit DexRegisterMap(MemoryRegion region) : region_(region) {}

	enum LocationKind {
	kNone,
	kInStack,
	kInRegister,
	kInFpuRegister,
	kConstant
	};

	LocationKind GetLocationKind(uint16_t register_index) const {
	return region_.Load<LocationKind>(
	kFixedSize + register_index * SingleEntrySize());
	}

	void SetRegisterInfo(uint16_t register_index, LocationKind kind, int32_t value) {
	size_t entry = kFixedSize + register_index * SingleEntrySize();
	region_.Store<LocationKind>(entry, kind);
	region_.Store<int32_t>(entry + sizeof(LocationKind), value);
	}

	int32_t GetValue(uint16_t register_index) const {
	return region_.Load<int32_t>(
	kFixedSize + sizeof(LocationKind) + register_index * SingleEntrySize());
	}

	static size_t SingleEntrySize() {
	return sizeof(LocationKind) + sizeof(int32_t);
	}

	private:
	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].
	*
	* Note that register_mask is fixed size, but stack_mask is variable size, depending on the
	* stack size of a method.
	*/
	class StackMap {
	public:
	explicit StackMap(MemoryRegion region) : region_(region) {}

	uint32_t GetDexPc() const {
	return region_.Load<uint32_t>(kDexPcOffset);
	}

	void SetDexPc(uint32_t dex_pc) {
	region_.Store<uint32_t>(kDexPcOffset, dex_pc);
	}

	uint32_t GetNativePcOffset() const {
	return region_.Load<uint32_t>(kNativePcOffsetOffset);
	}

	void SetNativePcOffset(uint32_t native_pc_offset) {
	return region_.Store<uint32_t>(kNativePcOffsetOffset, native_pc_offset);
	}

	uint32_t GetDexRegisterMapOffset() const {
	return region_.Load<uint32_t>(kDexRegisterMapOffsetOffset);
	}

	void SetDexRegisterMapOffset(uint32_t offset) {
	return region_.Store<uint32_t>(kDexRegisterMapOffsetOffset, offset);
	}

	uint32_t GetInlineDescriptorOffset() const {
	return region_.Load<uint32_t>(kInlineDescriptorOffsetOffset);
	}

	void SetInlineDescriptorOffset(uint32_t offset) {
	return region_.Store<uint32_t>(kInlineDescriptorOffsetOffset, offset);
	}

	uint32_t GetRegisterMask() const {
	return region_.Load<uint32_t>(kRegisterMaskOffset);
	}

	void SetRegisterMask(uint32_t mask) {
	region_.Store<uint32_t>(kRegisterMaskOffset, mask);
	}

	MemoryRegion GetStackMask() const {
	return region_.Subregion(kStackMaskOffset, StackMaskSize());
	}

	void SetStackMask(const BitVector& sp_map) {
	MemoryRegion region = GetStackMask();
	for (size_t i = 0; i < region.size_in_bits(); i++) {
	region.StoreBit(i, sp_map.IsBitSet(i));
	}
	}

	bool HasInlineInfo() const {
	return GetInlineDescriptorOffset() != InlineInfo::kNoInlineInfo;
	}

	bool Equals(const StackMap& other) {
	return region_.pointer() == other.region_.pointer()
	&& region_.size() == other.region_.size();
	}

	static size_t ComputeAlignedStackMapSize(size_t stack_mask_size) {
	// On ARM, the stack maps must be 4-byte aligned.
	return RoundUp(StackMap::kFixedSize + stack_mask_size, 4);
	}

	private:
	static constexpr int kDexPcOffset = 0;
	static constexpr int kNativePcOffsetOffset = kDexPcOffset + sizeof(uint32_t);
	static constexpr int kDexRegisterMapOffsetOffset = kNativePcOffsetOffset + sizeof(uint32_t);
	static constexpr int kInlineDescriptorOffsetOffset =
	kDexRegisterMapOffsetOffset + sizeof(uint32_t);
	static constexpr int kRegisterMaskOffset = kInlineDescriptorOffsetOffset + sizeof(uint32_t);
	static constexpr int kFixedSize = kRegisterMaskOffset + sizeof(uint32_t);
	static constexpr int kStackMaskOffset = kFixedSize;

	size_t StackMaskSize() const { return region_.size() - kFixedSize; }

	MemoryRegion region_;

	friend class CodeInfo;
	friend class StackMapStream;
	};


	/**
	* Wrapper around all compiler information collected for a method.
	* The information is of the form:
	* [overall_size, number_of_stack_maps, stack_mask_size, StackMap+, DexRegisterInfo+, 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);
	}

	StackMap GetStackMapAt(size_t i) const {
	size_t size = StackMapSize();
	return StackMap(GetStackMaps().Subregion(i * size, size));
	}

	uint32_t GetOverallSize() const {
	return region_.Load<uint32_t>(kOverallSizeOffset);
	}

	void SetOverallSize(uint32_t size) {
	region_.Store<uint32_t>(kOverallSizeOffset, size);
	}

	uint32_t GetStackMaskSize() const {
	return region_.Load<uint32_t>(kStackMaskSizeOffset);
	}

	void SetStackMaskSize(uint32_t size) {
	region_.Store<uint32_t>(kStackMaskSizeOffset, size);
	}

	size_t GetNumberOfStackMaps() const {
	return region_.Load<uint32_t>(kNumberOfStackMapsOffset);
	}

	void SetNumberOfStackMaps(uint32_t number_of_stack_maps) {
	region_.Store<uint32_t>(kNumberOfStackMapsOffset, number_of_stack_maps);
	}

	size_t StackMapSize() const {
	return StackMap::ComputeAlignedStackMapSize(GetStackMaskSize());
	}

	DexRegisterMap GetDexRegisterMapOf(StackMap stack_map, uint32_t number_of_dex_registers) {
	uint32_t offset = stack_map.GetDexRegisterMapOffset();
	return DexRegisterMap(region_.Subregion(offset,
	DexRegisterMap::kFixedSize + number_of_dex_registers * DexRegisterMap::SingleEntrySize()));
	}

	InlineInfo GetInlineInfoOf(StackMap stack_map) {
	uint32_t offset = stack_map.GetInlineDescriptorOffset();
	uint8_t depth = region_.Load<uint8_t>(offset);
	return InlineInfo(region_.Subregion(offset,
	InlineInfo::kFixedSize + depth * InlineInfo::SingleEntrySize()));
	}

	StackMap GetStackMapForDexPc(uint32_t dex_pc) {
	for (size_t i = 0, e = GetNumberOfStackMaps(); i < e; ++i) {
	StackMap stack_map = GetStackMapAt(i);
	if (stack_map.GetDexPc() == dex_pc) {
	return stack_map;
	}
	}
	LOG(FATAL) << "Unreachable";
	UNREACHABLE();
	}

	StackMap GetStackMapForNativePcOffset(uint32_t native_pc_offset) {
	// 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() == native_pc_offset) {
	return stack_map;
	}
	}
	LOG(FATAL) << "Unreachable";
	UNREACHABLE();
	}

	private:
	static constexpr int kOverallSizeOffset = 0;
	static constexpr int kNumberOfStackMapsOffset = kOverallSizeOffset + sizeof(uint32_t);
	static constexpr int kStackMaskSizeOffset = kNumberOfStackMapsOffset + sizeof(uint32_t);
	static constexpr int kFixedSize = kStackMaskSizeOffset + sizeof(uint32_t);

	MemoryRegion GetStackMaps() const {
	return region_.size() == 0
	? MemoryRegion()
	: region_.Subregion(kFixedSize, StackMapSize() * GetNumberOfStackMaps());
	}

	MemoryRegion region_;
	friend class StackMapStream;
	};

	} // namespace art

	#endif // ART_RUNTIME_STACK_MAP_H_