C++ ValueLocation类代码示例

status_t
AbstractArrayValueNode::ResolvedLocationAndValue(ValueLoader* valueLoader,
	ValueLocation*& _location, Value*& _value)
{
	// get the location
	ValueLocation* location = NodeChild()->Location();
	if (location == NULL)
		return B_BAD_VALUE;

	location->AcquireReference();
	_location = location;
	_value = NULL;
	return B_OK;
}

status_t
InternalArrayValueNodeChild::ResolveLocation(ValueLoader* valueLoader,
	ValueLocation*& _location)
{
	// This is an internal child node for a non-final dimension -- just clone
	// the parent's location.
	ValueLocation* parentLocation = fParent->Location();
	if (parentLocation == NULL)
		return B_BAD_VALUE;

	parentLocation->AcquireReference();
	_location = parentLocation;

	return B_OK;
}

status_t
BListValueNode::BListItemCountNodeChild::ResolveLocation(
	ValueLoader* valueLoader, ValueLocation*& _location)
{
	ValueLocation* location = new(std::nothrow) ValueLocation();
	if (location == NULL)
		return B_NO_MEMORY;

	ValuePieceLocation piece;
	piece.SetToMemory(fLocation.ToUInt64());
	piece.SetSize(sizeof(int32));
	location->AddPiece(piece);

	_location = location;
	return B_OK;
}

bool
ValueLocation::SetToByteOffset(const ValueLocation& other, uint64 byteOffset,
	uint64 byteSize)
{
	Clear();

	fBigEndian = other.fBigEndian;
	ValuePieceLocation piece = other.PieceAt(0);
	piece.SetToMemory(piece.address + byteOffset);
	piece.SetSize(byteSize);

	return AddPiece(piece);
}

	void SetInfo(Type* type, ValueLocation* location)
	{
		if (type != NULL)
			type->AcquireReference();
		if (location != NULL)
			location->AcquireReference();

		if (this->type != NULL)
			this->type->ReleaseReference();
		if (this->location != NULL)
			this->location->ReleaseReference();

		this->type = type;
		this->location = location;
	}

status_t
DwarfType::ResolveObjectDataLocation(const ValueLocation& objectLocation,
	ValueLocation*& _location)
{
	// TODO: In some source languages the object address might be a pointer
	// to a descriptor, not the actual object data.

	// If the given location looks good already, just clone it.
	int32 count = objectLocation.CountPieces();
	if (count == 0)
		return B_BAD_VALUE;

	ValuePieceLocation piece = objectLocation.PieceAt(0);
	if (count > 1 || piece.type != VALUE_PIECE_LOCATION_MEMORY
		|| piece.size != 0 || piece.bitSize != 0) {
		ValueLocation* location
			= new(std::nothrow) ValueLocation(objectLocation);
		if (location == NULL || location->CountPieces() != count) {
			delete location;
			return B_NO_MEMORY;
		}

		_location = location;
		return B_OK;
	}

	// The location contains just a single address piece with a zero size
	// -- set the type's size.
	piece.SetSize(ByteSize());
		// TODO: Use bit size and bit offset, if specified!

	ValueLocation* location = new(std::nothrow) ValueLocation(
		objectLocation.IsBigEndian());
	if (location == NULL || !location->AddPiece(piece)) {
		delete location;
		return B_NO_MEMORY;
	}

	_location = location;
	return B_OK;
}

status_t
DwarfExpressionEvaluator::EvaluateLocation(const void* expression, size_t size,
	ValueLocation& _location)
{
	_location.Clear();

	// the empty expression is a valid one
	if (size == 0) {
		ValuePieceLocation piece;
		piece.SetToUnknown();
		piece.SetSize(0);
		return _location.AddPiece(piece) ? B_OK : B_NO_MEMORY;
	}

	fDataReader.SetTo(expression, size, fContext->AddressSize());

	// parse the first (and maybe only) expression
	try {
		// push the object address, if any
		target_addr_t objectAddress;
		if (fContext->GetObjectAddress(objectAddress))
			_Push(objectAddress);

		ValuePieceLocation piece;
		status_t error = _Evaluate(&piece);
		if (error != B_OK)
			return error;

		// if that's all, it's only a simple expression without composition
		if (fDataReader.BytesRemaining() == 0) {
			if (!piece.IsValid())
				piece.SetToMemory(_Pop());
			piece.SetSize(0);
			return _location.AddPiece(piece) ? B_OK : B_NO_MEMORY;
		}

		// there's more, so it must be a composition operator
		uint8 opcode = fDataReader.Read<uint8>(0);
		if (opcode == DW_OP_piece) {
			piece.SetSize(fDataReader.ReadUnsignedLEB128(0));
		} else if (opcode == DW_OP_bit_piece) {
			uint64 bitSize = fDataReader.ReadUnsignedLEB128(0);
			piece.SetSize(bitSize, fDataReader.ReadUnsignedLEB128(0));
		} else
			return B_BAD_DATA;

		// If there's a composition operator, there must be at least two
		// simple expressions, so this must not be the end.
		if (fDataReader.BytesRemaining() == 0)
			return B_BAD_DATA;
	} catch (const EvaluationException& exception) {
		WARNING("DwarfExpressionEvaluator::EvaluateLocation(): %s\n",
			exception.message);
		return B_BAD_VALUE;
	} catch (const std::bad_alloc& exception) {
		return B_NO_MEMORY;
	}

	// parse subsequent expressions (at least one)
	while (fDataReader.BytesRemaining() > 0) {
		// Restrict the data reader to the remaining bytes to prevent jumping
		// back.
		fDataReader.SetTo(fDataReader.Data(), fDataReader.BytesRemaining(),
			fDataReader.AddressSize());

		try {
			// push the object address, if any
			target_addr_t objectAddress;
			if (fContext->GetObjectAddress(objectAddress))
				_Push(objectAddress);

			ValuePieceLocation piece;
			status_t error = _Evaluate(&piece);
			if (error != B_OK)
				return error;

			if (!piece.IsValid())
				piece.SetToMemory(_Pop());

			// each expression must be followed by a composition operator
			if (fDataReader.BytesRemaining() == 0)
				return B_BAD_DATA;

			uint8 opcode = fDataReader.Read<uint8>(0);
			if (opcode == DW_OP_piece) {
				piece.SetSize(fDataReader.ReadUnsignedLEB128(0));
			} else if (opcode == DW_OP_bit_piece) {
				uint64 bitSize = fDataReader.ReadUnsignedLEB128(0);
				piece.SetSize(bitSize, fDataReader.ReadUnsignedLEB128(0));
			} else
				return B_BAD_DATA;
		} catch (const EvaluationException& exception) {
			WARNING("DwarfExpressionEvaluator::EvaluateLocation(): %s\n",
				exception.message);
			return B_BAD_VALUE;
		} catch (const std::bad_alloc& exception) {
			return B_NO_MEMORY;
		}
	}

//.........这里部分代码省略.........

status_t
DwarfCompoundType::ResolveDataMemberLocation(DataMember* _member,
	const ValueLocation& parentLocation, ValueLocation*& _location)
{
	DwarfDataMember* member = dynamic_cast<DwarfDataMember*>(_member);
	if (member == NULL)
		return B_BAD_VALUE;
	DwarfTypeContext* typeContext = TypeContext();

	bool isBitField = true;
	DIEMember* memberEntry = member->Entry();
	// TODO: handle DW_AT_data_bit_offset
	if (!memberEntry->ByteSize()->IsValid()
		&& !memberEntry->BitOffset()->IsValid()
		&& !memberEntry->BitSize()->IsValid()) {
		isBitField = false;
	}

	ValueLocation* location;
	status_t error = _ResolveDataMemberLocation(member->GetDwarfType(),
		member->Entry()->Location(), parentLocation, isBitField, location);
	if (error != B_OK)
		return error;

	// If the member isn't a bit field, we're done.
	if (!isBitField) {
		_location = location;
		return B_OK;
	}

	BReference<ValueLocation> locationReference(location);

	// get the byte size
	target_addr_t byteSize;
	if (memberEntry->ByteSize()->IsValid()) {
		BVariant value;
		error = typeContext->File()->EvaluateDynamicValue(
			typeContext->GetCompilationUnit(), typeContext->AddressSize(),
			typeContext->SubprogramEntry(), memberEntry->ByteSize(),
			typeContext->TargetInterface(), typeContext->InstructionPointer(),
			typeContext->FramePointer(), value);
		if (error != B_OK)
			return error;
		byteSize = value.ToUInt64();
	} else
		byteSize = ByteSize();

	// get the bit offset
	uint64 bitOffset = 0;
	if (memberEntry->BitOffset()->IsValid()) {
		BVariant value;
		error = typeContext->File()->EvaluateDynamicValue(
			typeContext->GetCompilationUnit(), typeContext->AddressSize(),
			typeContext->SubprogramEntry(), memberEntry->BitOffset(),
			typeContext->TargetInterface(), typeContext->InstructionPointer(),
			typeContext->FramePointer(), value);
		if (error != B_OK)
			return error;
		bitOffset = value.ToUInt64();
	}

	// get the bit size
	uint64 bitSize = byteSize * 8;
	if (memberEntry->BitSize()->IsValid()) {
		BVariant value;
		error = typeContext->File()->EvaluateDynamicValue(
			typeContext->GetCompilationUnit(), typeContext->AddressSize(),
			typeContext->SubprogramEntry(), memberEntry->BitSize(),
			typeContext->TargetInterface(), typeContext->InstructionPointer(),
			typeContext->FramePointer(), value);
		if (error != B_OK)
			return error;
		bitSize = value.ToUInt64();
	}

	TRACE_LOCALS("bit field: byte size: %" B_PRIu64 ", bit offset/size: %"
		B_PRIu64 "/%" B_PRIu64 "\n", byteSize, bitOffset, bitSize);

	if (bitOffset + bitSize > byteSize * 8)
		return B_BAD_VALUE;

	// create the bit field value location
	ValueLocation* bitFieldLocation = new(std::nothrow) ValueLocation;
	if (bitFieldLocation == NULL)
		return B_NO_MEMORY;
	BReference<ValueLocation> bitFieldLocationReference(bitFieldLocation, true);

	if (!bitFieldLocation->SetTo(*location, bitOffset, bitSize))
		return B_NO_MEMORY;

	_location = bitFieldLocationReference.Detach();
	return B_OK;
}

status_t
DwarfType::ResolveLocation(DwarfTypeContext* typeContext,
	const LocationDescription* description, target_addr_t objectAddress,
	bool hasObjectAddress, ValueLocation& _location)
{
	status_t error = typeContext->File()->ResolveLocation(
		typeContext->GetCompilationUnit(), typeContext->AddressSize(),
		typeContext->SubprogramEntry(), description,
		typeContext->TargetInterface(), typeContext->InstructionPointer(),
		objectAddress, hasObjectAddress, typeContext->FramePointer(),
		typeContext->RelocationDelta(), _location);
	if (error != B_OK)
		return error;

	// translate the DWARF register indices and the bit offset/size semantics
	const Register* registers = typeContext->GetArchitecture()->Registers();
	bool bigEndian = typeContext->GetArchitecture()->IsBigEndian();
	int32 count = _location.CountPieces();
	for (int32 i = 0; i < count; i++) {
		ValuePieceLocation piece = _location.PieceAt(i);
		if (piece.type == VALUE_PIECE_LOCATION_REGISTER) {
			int32 reg = typeContext->FromDwarfRegisterMap()->MapRegisterIndex(
				piece.reg);
			if (reg >= 0) {
				piece.reg = reg;
				// The bit offset for registers is to the least
				// significant bit, while we want the offset to the most
				// significant bit.
				if (registers[reg].BitSize() > piece.bitSize) {
					piece.bitOffset = registers[reg].BitSize() - piece.bitSize
						- piece.bitOffset;
				}
			} else
				piece.SetToUnknown();
		} else if (piece.type == VALUE_PIECE_LOCATION_MEMORY) {
			// Whether the bit offset is to the least or most significant bit
			// is target architecture and source language specific.
			// TODO: Check whether this is correct!
			// TODO: Source language!
			if (!bigEndian && piece.size * 8 > piece.bitSize) {
				piece.bitOffset = piece.size * 8 - piece.bitSize
					- piece.bitOffset;
			}
		}

		piece.Normalize(bigEndian);
		_location.SetPieceAt(i, piece);
	}

	// If we only have one piece and that doesn't have a size, try to retrieve
	// the size of the type.
	if (count == 1) {
		ValuePieceLocation piece = _location.PieceAt(0);
		if (piece.IsValid() && piece.size == 0 && piece.bitSize == 0) {
			piece.SetSize(ByteSize());
				// TODO: Use bit size and bit offset, if specified!
			_location.SetPieceAt(0, piece);

			TRACE_LOCALS("  set single piece size to %" B_PRIu64 "\n",
				ByteSize());
		}
	}

	return B_OK;
}

bool
ValueLocation::SetTo(const ValueLocation& other, uint64 bitOffset,
	uint64 bitSize)
{
	Clear();

	fBigEndian = other.fBigEndian;

	// compute the total bit size
	int32 count = other.CountPieces();
	uint64 totalBitSize = 0;
	for (int32 i = 0; i < count; i++) {
		const ValuePieceLocation &piece = other.PieceAt(i);
		totalBitSize += piece.bitSize;
	}

	// adjust requested bit offset/size to something reasonable, if necessary
	if (bitOffset + bitSize > totalBitSize) {
		if (bitOffset >= totalBitSize)
			return true;
		bitSize = totalBitSize - bitOffset;
	}

	if (fBigEndian) {
		// Big endian: Skip the superfluous most significant bits, copy the
		// pieces we need (cutting the first and the last one as needed) and
		// ignore the remaining pieces.

		// skip pieces for the most significant bits we don't need anymore
		uint64 bitsToSkip = bitOffset;
		int32 i;
		ValuePieceLocation piece;
		for (i = 0; i < count; i++) {
			const ValuePieceLocation& tempPiece = other.PieceAt(i);
			if (tempPiece.bitSize > bitsToSkip) {
				if (!piece.Copy(tempPiece))
					return false;
				break;
			}
			bitsToSkip -= tempPiece.bitSize;
		}

		// handle partial piece
		if (bitsToSkip > 0) {
			piece.bitOffset += bitsToSkip;
			piece.bitSize -= bitsToSkip;
			piece.Normalize(fBigEndian);
		}

		// handle remaining pieces
		while (bitSize > 0) {
			if (piece.bitSize > bitSize) {
				// the piece is bigger than the remaining size -- cut it
				piece.bitSize = bitSize;
				piece.Normalize(fBigEndian);
				bitSize = 0;
			} else
				bitSize -= piece.bitSize;

			if (!AddPiece(piece))
				return false;

			if (++i >= count)
				break;

			if (!piece.Copy(other.PieceAt(i)))
				return false;
		}
	} else {
		// Little endian: Skip the superfluous least significant bits, copy the
		// pieces we need (cutting the first and the last one as needed) and
		// ignore the remaining pieces.

		// skip pieces for the least significant bits we don't need anymore
		uint64 bitsToSkip = totalBitSize - bitOffset - bitSize;
		int32 i;
		ValuePieceLocation piece;
		for (i = 0; i < count; i++) {
			const ValuePieceLocation& tempPiece = other.PieceAt(i);
			if (tempPiece.bitSize > bitsToSkip) {
				if (!piece.Copy(tempPiece))
					return false;
				break;
			}
			bitsToSkip -= piece.bitSize;
		}

		// handle partial piece
		if (bitsToSkip > 0) {
			piece.bitSize -= bitsToSkip;
			piece.Normalize(fBigEndian);
		}

		// handle remaining pieces
		while (bitSize > 0) {
			if (piece.bitSize > bitSize) {
				// the piece is bigger than the remaining size -- cut it
				piece.bitOffset += piece.bitSize - bitSize;
				piece.bitSize = bitSize;
				piece.Normalize(fBigEndian);
//.........这里部分代码省略.........

status_t
BListValueNode::ResolvedLocationAndValue(ValueLoader* valueLoader,
	ValueLocation*& _location, Value*& _value)
{
	// get the location
	ValueLocation* location = NodeChild()->Location();
	if (location == NULL)
		return B_BAD_VALUE;


	// get the value type
	type_code valueType;
	if (valueLoader->GetArchitecture()->AddressSize() == 4) {
		valueType = B_UINT32_TYPE;
		TRACE_LOCALS("    -> 32 bit\n");
	} else {
		valueType = B_UINT64_TYPE;
		TRACE_LOCALS("    -> 64 bit\n");
	}

	// load the value data

	status_t error = B_OK;
	_location = location;
	_value = NULL;

	ValueLocation* memberLocation = NULL;
	CompoundType* baseType = dynamic_cast<CompoundType*>(fType);

	if (baseType->CountTemplateParameters() != 0) {
		// for BObjectList we need to walk up
		// the hierarchy: BObjectList -> _PointerList_ -> BList
		if (baseType->CountBaseTypes() == 0)
			return B_BAD_DATA;

		baseType = dynamic_cast<CompoundType*>(baseType->BaseTypeAt(0)
			->GetType());
		if (baseType == NULL || baseType->Name() != "_PointerList_")
			return B_BAD_DATA;

		if (baseType->CountBaseTypes() == 0)
			return B_BAD_DATA;

		baseType = dynamic_cast<CompoundType*>(baseType->BaseTypeAt(0)
			->GetType());
		if (baseType == NULL || baseType->Name() != "BList")
			return B_BAD_DATA;

	}

	for (int32 i = 0; i < baseType->CountDataMembers(); i++) {
		DataMember* member = baseType->DataMemberAt(i);
		if (strcmp(member->Name(), "fObjectList") == 0) {
			error = baseType->ResolveDataMemberLocation(member,
				*location, memberLocation);
			BReference<ValueLocation> locationRef(memberLocation, true);
			if (error != B_OK) {
				TRACE_LOCALS(
					"BListValueNode::ResolvedLocationAndValue(): "
					"failed to resolve location of header member: %s\n",
					strerror(error));
				return error;
			}

			error = valueLoader->LoadValue(memberLocation, valueType,
				false, fDataLocation);
			if (error != B_OK)
				return error;
		} else if (strcmp(member->Name(), "fItemCount") == 0) {
			error = baseType->ResolveDataMemberLocation(member,
				*location, memberLocation);
			BReference<ValueLocation> locationRef(memberLocation, true);
			if (error != B_OK) {
				TRACE_LOCALS(
					"BListValueNode::ResolvedLocationAndValue(): "
					"failed to resolve location of header member: %s\n",
					strerror(error));
				return error;
			}

			fItemCountType = member->GetType();
			fItemCountType->AcquireReference();

			fItemCountLocation = memberLocation->PieceAt(0).address;

			BVariant listSize;
			error = valueLoader->LoadValue(memberLocation, valueType,
				false, listSize);
			if (error != B_OK)
				return error;

			fItemCount = listSize.ToInt32();
			TRACE_LOCALS(
				"BListValueNode::ResolvedLocationAndValue(): "
				"detected list size %" B_PRId32 "\n",
				fItemCount);
		}
		memberLocation = NULL;
	}

//.........这里部分代码省略.........