#include <DWARFExpression.h>

Collaboration diagram for lldb_private::DWARFExpression:

[legend]

Classes
struct	LoclistAddresses

Public Member Functions
	DWARFExpression ()

	DWARFExpression (lldb::ModuleSP module, const DataExtractor &data, const DWARFUnit *dwarf_cu)
	Constructor. More...

virtual	~DWARFExpression ()
	Destructor. More...

void	GetDescription (Stream s, lldb::DescriptionLevel level, lldb::addr_t location_list_base_addr, ABI abi) const
	Print the description of the expression to a stream. More...

bool	IsValid () const
	Return true if the location expression contains data. More...

bool	IsLocationList () const
	Return true if a location list was provided. More...

bool	LocationListContainsAddress (lldb::addr_t func_load_addr, lldb::addr_t addr) const
	Search for a load address in the location list. More...

lldb::addr_t	GetLocation_DW_OP_addr (uint32_t op_addr_idx, bool &error) const
	If a location is not a location list, return true if the location contains a DW_OP_addr () opcode in the stream that matches file_addr. More...

bool	Update_DW_OP_addr (lldb::addr_t file_addr)

void	UpdateValue (uint64_t const_value, lldb::offset_t const_value_byte_size, uint8_t addr_byte_size)

void	SetModule (const lldb::ModuleSP &module)

bool	ContainsThreadLocalStorage () const

bool	LinkThreadLocalStorage (lldb::ModuleSP new_module_sp, std::function< lldb::addr_t(lldb::addr_t file_addr)> const &link_address_callback)

void	SetLocationListAddresses (lldb::addr_t cu_file_addr, lldb::addr_t func_file_addr)
	Tells the expression that it refers to a location list. More...

int	GetRegisterKind ()
	Return the call-frame-info style register kind. More...

void	SetRegisterKind (lldb::RegisterKind reg_kind)
	Set the call-frame-info style register kind. More...

bool	Evaluate (ExecutionContextScope exe_scope, lldb::addr_t func_load_addr, const Value initial_value_ptr, const Value object_address_ptr, Value &result, Status error_ptr) const
	Wrapper for the static evaluate function that accepts an ExecutionContextScope instead of an ExecutionContext and uses member variables to populate many operands. More...

bool	Evaluate (ExecutionContext exe_ctx, RegisterContext reg_ctx, lldb::addr_t loclist_base_load_addr, const Value initial_value_ptr, const Value object_address_ptr, Value &result, Status *error_ptr) const
	Wrapper for the static evaluate function that uses member variables to populate many operands. More...

bool	GetExpressionData (DataExtractor &data) const

bool	DumpLocationForAddress (Stream s, lldb::DescriptionLevel level, lldb::addr_t func_load_addr, lldb::addr_t address, ABI abi)

bool	MatchesOperand (StackFrame &frame, const Instruction::Operand &op)

llvm::Optional< DataExtractor >	GetLocationExpression (lldb::addr_t load_function_start, lldb::addr_t addr) const

Static Public Member Functions
static bool	Evaluate (ExecutionContext exe_ctx, RegisterContext reg_ctx, lldb::ModuleSP opcode_ctx, const DataExtractor &opcodes, const DWARFUnit dwarf_cu, const lldb::RegisterKind reg_set, const Value initial_value_ptr, const Value object_address_ptr, Value &result, Status error_ptr)
	Evaluate a DWARF location expression in a particular context. More...

Private Member Functions
void	DumpLocation (Stream s, const DataExtractor &data, lldb::DescriptionLevel level, ABI abi) const
	Pretty-prints the location expression to a stream. More...

Private Attributes
lldb::ModuleWP	m_module_wp
	Module which defined this expression. More...

DataExtractor	m_data
	A data extractor capable of reading opcode bytes. More...

const DWARFUnit *	m_dwarf_cu = nullptr
	The DWARF compile unit this expression belongs to. More...

lldb::RegisterKind	m_reg_kind = lldb::eRegisterKindDWARF
	One of the defines that starts with LLDB_REGKIND_. More...

llvm::Optional< LoclistAddresses >	m_loclist_addresses

Detailed Description

"lldb/Expression/DWARFExpression.h" Encapsulates a DWARF location expression and interprets it.

DWARF location expressions are used in two ways by LLDB. The first use is to find entities specified in the debug information, since their locations are specified in precisely this language. The second is to interpret expressions without having to run the target in cases where the overhead from copying JIT-compiled code into the target is too high or where the target cannot be run. This class encapsulates a single DWARF location expression or a location list and interprets it.

Definition at line 35 of file DWARFExpression.h.

Constructor & Destructor Documentation

◆ DWARFExpression() [1/2]

DWARFExpression::DWARFExpression ( )

Definition at line 58 of file DWARFExpression.cpp.

◆ DWARFExpression() [2/2]

DWARFExpression::DWARFExpression	(	lldb::ModuleSP	module,
		const DataExtractor &	data,
		const DWARFUnit *	dwarf_cu
	)

Constructor.

Parameters

[in] data A data extractor configured to read the DWARF location expression's bytecode.

Definition at line 60 of file DWARFExpression.cpp.

References m_module_wp.

◆ ~DWARFExpression()

DWARFExpression::~DWARFExpression ( )

virtualdefault

Destructor.

Member Function Documentation

◆ ContainsThreadLocalStorage()

bool DWARFExpression::ContainsThreadLocalStorage ( ) const

Definition at line 490 of file DWARFExpression.cpp.

References GetOpcodeDataSize(), lldb_private::DataExtractor::GetU8(), IsLocationList(), LLDB_INVALID_OFFSET, m_data, and lldb_private::DataExtractor::ValidOffset().

Referenced by SymbolFileDWARF::ParseVariableDIE().

◆ DumpLocation()

void DWARFExpression::DumpLocation	(	Stream *	s,
		const DataExtractor &	data,
		lldb::DescriptionLevel	level,
		ABI *	abi
	)		const

private

Pretty-prints the location expression to a stream.

Parameters

[in]	s	The stream to use for pretty-printing.
[in]	data	The data extractor.
[in]	level	The level of detail to use in pretty-printing.
[in]	abi	An optional ABI plug-in that can be used to resolve register names.

Definition at line 86 of file DWARFExpression.cpp.

References lldb_private::Stream::AsRawOstream(), lldb_private::DataExtractor::GetAddressByteSize(), lldb_private::DataExtractor::GetAsLLVM(), and lldb_private::ABI::GetMCRegisterInfo().

Referenced by DumpLocationForAddress(), and GetDescription().

◆ DumpLocationForAddress()

bool DWARFExpression::DumpLocationForAddress	(	Stream *	s,
		lldb::DescriptionLevel	level,
		lldb::addr_t	func_load_addr,
		lldb::addr_t	address,
		ABI *	abi
	)

Definition at line 621 of file DWARFExpression.cpp.

References DumpLocation(), GetLocationExpression(), IsLocationList(), and m_data.

Referenced by lldb_private::Variable::DumpLocationForAddress(), and SymbolFileDWARF::ParseVariableDIE().

◆ Evaluate() [1/3]

bool DWARFExpression::Evaluate	(	ExecutionContext *	exe_ctx,
		RegisterContext *	reg_ctx,
		lldb::addr_t	loclist_base_load_addr,
		const Value *	initial_value_ptr,
		const Value *	object_address_ptr,
		Value &	result,
		Status *	error_ptr
	)		const

Wrapper for the static evaluate function that uses member variables to populate many operands.

Definition at line 857 of file DWARFExpression.cpp.

References Evaluate(), lldb_private::ExecutionContext::GetFramePtr(), GetLocationExpression(), lldb_private::RegisterContext::GetPC(), lldb_private::StackFrame::GetRegisterContext(), IsLocationList(), LLDB_INVALID_ADDRESS, m_data, m_dwarf_cu, m_module_wp, m_reg_kind, pc, and lldb_private::Status::SetErrorString().

◆ Evaluate() [2/3]

bool DWARFExpression::Evaluate	(	ExecutionContext *	exe_ctx,
		RegisterContext *	reg_ctx,
		lldb::ModuleSP	opcode_ctx,
		const DataExtractor &	opcodes,
		const DWARFUnit *	dwarf_cu,
		const lldb::RegisterKind	reg_set,
		const Value *	initial_value_ptr,
		const Value *	object_address_ptr,
		Value &	result,
		Status *	error_ptr
	)

static

Evaluate a DWARF location expression in a particular context.

Parameters

[in]	exe_ctx	The execution context in which to evaluate the location expression. The location expression may access the target's memory, especially if it comes from the expression parser.
[in]	opcode_ctx	The module which defined the expression.
[in]	opcodes	This is a static method so the opcodes need to be provided explicitly.
[in]	reg_ctx	An optional parameter which provides a RegisterContext for use when evaluating the expression (i.e. for fetching register values). Normally this will come from the ExecutionContext's StackFrame but in the case where an expression needs to be evaluated while building the stack frame list, this short-cut is available.
[in]	reg_set	The call-frame-info style register kind.
[in]	initial_value_ptr	A value to put on top of the interpreter stack before evaluating the expression, if the expression is parametrized. Can be NULL.
[in]	result	A value into which the result of evaluating the expression is to be placed.
[in]	error_ptr	If non-NULL, used to report errors in expression evaluation.

Returns: True on success; false otherwise. If error_ptr is non-NULL, details of the failure are provided through it.

Insertion point for evaluating multi-piece expression.

Definition at line 951 of file DWARFExpression.cpp.

◆ Evaluate() [3/3]

bool DWARFExpression::Evaluate	(	ExecutionContextScope *	exe_scope,
		lldb::addr_t	func_load_addr,
		const Value *	initial_value_ptr,
		const Value *	object_address_ptr,
		Value &	result,
		Status *	error_ptr
	)		const

Wrapper for the static evaluate function that accepts an ExecutionContextScope instead of an ExecutionContext and uses member variables to populate many operands.

Definition at line 847 of file DWARFExpression.cpp.

Referenced by Evaluate(), Evaluate_DW_OP_entry_value(), lldb_private::IndirectCallEdge::GetCallee(), lldb_private::StackFrame::GetFrameBaseValue(), SymbolFileDWARF::GetGlobalAranges(), lldb_private::RegisterContextUnwind::ReadFrameAddress(), lldb_private::RegisterContextUnwind::SavedLocationForRegister(), lldb_private::RegisterContext::UpdateDynamicRegisterSize(), and lldb_private::ValueObjectVariable::UpdateValue().

◆ GetDescription()

void DWARFExpression::GetDescription	(	Stream *	s,
		lldb::DescriptionLevel	level,
		lldb::addr_t	location_list_base_addr,
		ABI *	abi
	)		const

Print the description of the expression to a stream.

Parameters

[in]	s	The stream to print to.
[in]	level	The level of verbosity to use.
[in]	location_list_base_addr	If this is a location list based expression, this is the address of the object that owns it. NOTE: this value is different from the DWARF version of the location list base address which is compile unit relative. This base address is the address of the object that owns the location list.
[in]	abi	An optional ABI plug-in that can be used to resolve register names.

Definition at line 128 of file DWARFExpression.cpp.

References lldb_private::Stream::AsRawOstream(), DumpLocation(), lldb::eByteOrderLittle, lldb_private::DataExtractor::GetByteOrder(), lldb_private::Stream::GetIndentLevel(), DWARFUnit::GetLocationTable(), lldb_private::ABI::GetMCRegisterInfo(), IsLocationList(), m_data, m_dwarf_cu, and lldb_private::toString().

Referenced by lldb_private::Variable::Dump().

◆ GetExpressionData()

bool lldb_private::DWARFExpression::GetExpressionData ( DataExtractor & data ) const

inline

Definition at line 211 of file DWARFExpression.h.

References lldb_private::DataExtractor::GetByteSize(), and m_data.

Referenced by lldb_private::ClangExpressionDeclMap::GetVariableValue(), and lldb_private::ValueObjectVariable::UpdateValue().

◆ GetLocation_DW_OP_addr()

lldb::addr_t DWARFExpression::GetLocation_DW_OP_addr	(	uint32_t	op_addr_idx,
		bool &	error
	)		const

If a location is not a location list, return true if the location contains a DW_OP_addr () opcode in the stream that matches file_addr.

If file_addr is LLDB_INVALID_ADDRESS, the this function will return true if the variable there is any DW_OP_addr in a location that (yet still is NOT a location list). This helps us detect if a variable is a global or static variable since there is no other indication from DWARF debug info.

Parameters

[in]	op_addr_idx	The DW_OP_addr index to retrieve in case there is more than one DW_OP_addr opcode in the location byte stream.
[out]	error	If the location stream contains unknown DW_OP opcodes or the data is missing, error will be set to true.

Returns: LLDB_INVALID_ADDRESS if the location doesn't contain a DW_OP_addr for op_addr_idx, otherwise a valid file address

Definition at line 410 of file DWARFExpression.cpp.

References error(), lldb_private::DataExtractor::GetAddress(), GetOpcodeDataSize(), lldb_private::DataExtractor::GetU8(), lldb_private::DataExtractor::GetULEB128(), IsLocationList(), LLDB_INVALID_ADDRESS, LLDB_INVALID_OFFSET, m_data, m_dwarf_cu, ReadAddressFromDebugAddrSection(), and lldb_private::DataExtractor::ValidOffset().

Referenced by SymbolFileDWARF::ParseVariableDIE().

◆ GetLocationExpression()

llvm::Optional< DataExtractor > DWARFExpression::GetLocationExpression	(	lldb::addr_t	load_function_start,
		lldb::addr_t	addr
	)		const

Definition at line 2681 of file DWARFExpression.cpp.

References lldb_private::DataExtractor::GetAddressByteSize(), lldb_private::DataExtractor::GetByteOrder(), DWARFUnit::GetLocationTable(), lldb_private::GetLogIfAllCategoriesSet(), LIBLLDB_LOG_EXPRESSIONS, LLDB_INVALID_ADDRESS, LLDB_LOG_ERROR, m_data, m_dwarf_cu, m_loclist_addresses, ReadAddressFromDebugAddrSection(), and ToDataExtractor().

Referenced by DumpLocationForAddress(), Evaluate(), LocationListContainsAddress(), and MatchesOperand().

◆ GetRegisterKind()

int DWARFExpression::GetRegisterKind ( )

Return the call-frame-info style register kind.

Definition at line 99 of file DWARFExpression.cpp.

References m_reg_kind.

◆ IsLocationList()

bool DWARFExpression::IsLocationList ( ) const

Return true if a location list was provided.

Definition at line 105 of file DWARFExpression.cpp.

References m_loclist_addresses.

Referenced by ContainsThreadLocalStorage(), lldb_private::Variable::Dump(), DumpLocationForAddress(), Evaluate(), GetDescription(), lldb_private::StackFrame::GetFrameBaseValue(), GetLocation_DW_OP_addr(), LinkThreadLocalStorage(), lldb_private::Variable::LocationIsValidForAddress(), lldb_private::Variable::LocationIsValidForFrame(), LocationListContainsAddress(), MatchesOperand(), Update_DW_OP_addr(), and lldb_private::ValueObjectVariable::UpdateValue().

◆ IsValid()

bool DWARFExpression::IsValid ( ) const

Return true if the location expression contains data.

Definition at line 72 of file DWARFExpression.cpp.

References lldb_private::DataExtractor::GetByteSize(), and m_data.

Referenced by lldb_private::Variable::Dump(), DWARFASTParserClang::ParseFunctionFromDWARF(), and SymbolFileDWARF::ParseVariableDIE().

◆ LinkThreadLocalStorage()

bool DWARFExpression::LinkThreadLocalStorage	(	lldb::ModuleSP	new_module_sp,
		std::function< lldb::addr_t(lldb::addr_t file_addr)> const &	link_address_callback
	)

Definition at line 510 of file DWARFExpression.cpp.

Referenced by SymbolFileDWARF::ParseVariableDIE().

◆ LocationListContainsAddress()

bool DWARFExpression::LocationListContainsAddress	(	lldb::addr_t	func_load_addr,
		lldb::addr_t	addr
	)		const

Search for a load address in the location list.

Parameters

[in]	func_load_addr	The actual address of the function containing this location list.
[in]	addr	The address to resolve

Returns: True if IsLocationList() is true and the address was found; false otherwise.

Definition at line 610 of file DWARFExpression.cpp.

References GetLocationExpression(), IsLocationList(), and LLDB_INVALID_ADDRESS.

Referenced by lldb_private::Variable::LocationIsValidForAddress(), and lldb_private::Variable::LocationIsValidForFrame().

◆ MatchesOperand()

bool DWARFExpression::MatchesOperand	(	StackFrame &	frame,
		const Instruction::Operand &	op
	)

Definition at line 2722 of file DWARFExpression.cpp.

References lldb_private::StackFrame::CalculateTarget(), lldb_private::Instruction::Operand::Dereference, lldb_private::SymbolContext::function, lldb_private::Function::GetAddressRange(), lldb_private::AddressRange::GetBaseAddress(), lldb_private::Address::GetFileAddress(), lldb_private::StackFrame::GetFrameBaseExpression(), lldb_private::StackFrame::GetFrameCodeAddress(), lldb_private::Address::GetLoadAddress(), GetLocationExpression(), lldb_private::StackFrame::GetRegisterContext(), lldb_private::DataExtractor::GetSLEB128(), lldb_private::StackFrame::GetSymbolContext(), lldb_private::DataExtractor::GetU8(), lldb_private::DataExtractor::GetULEB128(), IsLocationList(), LLDB_INVALID_ADDRESS, m_data, m_reg_kind, lldb_private::OperandMatchers::MatchBinaryOp, MatchesOperand(), lldb_private::OperandMatchers::MatchImmOp, lldb_private::OperandMatchers::MatchOpType, lldb_private::OperandMatchers::MatchRegOp, lldb_private::OperandMatchers::MatchUnaryOp, pc, and lldb_private::Instruction::Operand::Sum.

Referenced by MatchesOperand().

◆ SetLocationListAddresses()

void DWARFExpression::SetLocationListAddresses	(	lldb::addr_t	cu_file_addr,
		lldb::addr_t	func_file_addr
	)

Tells the expression that it refers to a location list.

Parameters

[in]	cu_file_addr	The base address to use for interpreting relative location list entries.
[in]	func_file_addr	The file address of the function containing this location list. This address will be used to relocate the location list on the fly (in conjuction with the func_load_addr arguments).

Definition at line 94 of file DWARFExpression.cpp.

References m_loclist_addresses.

Referenced by DWARFDebugInfoEntry::GetDIENamesAndRanges(), and SymbolFileDWARF::ParseVariableDIE().

◆ SetModule()

void lldb_private::DWARFExpression::SetModule ( const lldb::ModuleSP & module )

inline

Definition at line 121 of file DWARFExpression.h.

References m_module_wp.

Referenced by SymbolFileDWARF::ParseVariableDIE().

◆ SetRegisterKind()

void DWARFExpression::SetRegisterKind ( lldb::RegisterKind reg_kind )

Set the call-frame-info style register kind.

Parameters

[in] reg_kind The register kind.

Definition at line 101 of file DWARFExpression.cpp.

References m_reg_kind.

Referenced by ConvertPDBLocationToDWARFExpression(), MakeLocationExpressionInternal(), lldb_private::RegisterContextUnwind::ReadFrameAddress(), and lldb_private::RegisterContextUnwind::SavedLocationForRegister().

◆ Update_DW_OP_addr()

bool DWARFExpression::Update_DW_OP_addr ( lldb::addr_t file_addr )

Definition at line 449 of file DWARFExpression.cpp.

References lldb_private::DataExtractor::GetAddressByteSize(), lldb_private::DataExtractor::GetByteOrder(), lldb_private::DataExtractor::GetByteSize(), lldb_private::DataExtractor::GetDataStart(), GetOpcodeDataSize(), lldb_private::DataExtractor::GetU8(), IsLocationList(), LLDB_INVALID_OFFSET, m_data, lldb_private::DataExtractor::SetData(), UINT32_MAX, and lldb_private::DataExtractor::ValidOffset().

Referenced by SymbolFileDWARF::ParseVariableDIE().

◆ UpdateValue()

void DWARFExpression::UpdateValue	(	uint64_t	const_value,
		lldb::offset_t	const_value_byte_size,
		uint8_t	addr_byte_size
	)

Definition at line 74 of file DWARFExpression.cpp.

References lldb_private::endian::InlHostByteOrder(), m_data, lldb_private::DataExtractor::SetAddressByteSize(), lldb_private::DataExtractor::SetByteOrder(), and lldb_private::DataExtractor::SetData().

Referenced by SymbolFileDWARF::ParseVariableDIE().

Member Data Documentation

◆ m_data

DataExtractor lldb_private::DWARFExpression::m_data

private

A data extractor capable of reading opcode bytes.

Definition at line 248 of file DWARFExpression.h.

Referenced by ContainsThreadLocalStorage(), DumpLocationForAddress(), Evaluate(), GetDescription(), GetExpressionData(), GetLocation_DW_OP_addr(), GetLocationExpression(), IsValid(), LinkThreadLocalStorage(), MatchesOperand(), Update_DW_OP_addr(), and UpdateValue().

◆ m_dwarf_cu

const DWARFUnit* lldb_private::DWARFExpression::m_dwarf_cu = nullptr

private

The DWARF compile unit this expression belongs to.

It is used to evaluate values indexing into the .debug_addr section (e.g. DW_OP_GNU_addr_index, DW_OP_GNU_const_index)

Definition at line 253 of file DWARFExpression.h.

Referenced by Evaluate(), GetDescription(), GetLocation_DW_OP_addr(), and GetLocationExpression().

◆ m_loclist_addresses

llvm::Optional<LoclistAddresses> lldb_private::DWARFExpression::m_loclist_addresses

private

Definition at line 262 of file DWARFExpression.h.

Referenced by GetLocationExpression(), IsLocationList(), and SetLocationListAddresses().

◆ m_module_wp

lldb::ModuleWP lldb_private::DWARFExpression::m_module_wp

private

Module which defined this expression.

Definition at line 245 of file DWARFExpression.h.

Referenced by DWARFExpression(), Evaluate(), LinkThreadLocalStorage(), and SetModule().

◆ m_reg_kind

lldb::RegisterKind lldb_private::DWARFExpression::m_reg_kind = lldb::eRegisterKindDWARF

private

One of the defines that starts with LLDB_REGKIND_.

Definition at line 256 of file DWARFExpression.h.

Referenced by Evaluate(), GetRegisterKind(), MatchesOperand(), and SetRegisterKind().

The documentation for this class was generated from the following files:

Classes

Public Member Functions

Static Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ DWARFExpression() [1/2]

◆ DWARFExpression() [2/2]

◆ ~DWARFExpression()

Member Function Documentation

◆ ContainsThreadLocalStorage()

◆ DumpLocation()

◆ DumpLocationForAddress()

◆ Evaluate() [1/3]

◆ Evaluate() [2/3]

◆ Evaluate() [3/3]

◆ GetDescription()

◆ GetExpressionData()

◆ GetLocation_DW_OP_addr()

◆ GetLocationExpression()

◆ GetRegisterKind()

◆ IsLocationList()

◆ IsValid()

◆ LinkThreadLocalStorage()

◆ LocationListContainsAddress()

◆ MatchesOperand()

◆ SetLocationListAddresses()

◆ SetModule()

◆ SetRegisterKind()

◆ Update_DW_OP_addr()

◆ UpdateValue()

Member Data Documentation

◆ m_data

◆ m_dwarf_cu

◆ m_loclist_addresses

◆ m_module_wp

◆ m_reg_kind