DWARFExpression.cpp File Reference

#include "lldb/Expression/DWARFExpression.h"
#include <cinttypes>
#include <limits>
#include <optional>
#include <vector>
#include "lldb/Core/Module.h"
#include "lldb/Core/Value.h"
#include "lldb/Utility/DataEncoder.h"
#include "lldb/Utility/LLDBLog.h"
#include "lldb/Utility/Log.h"
#include "lldb/Utility/RegisterValue.h"
#include "lldb/Utility/Scalar.h"
#include "lldb/Utility/StreamString.h"
#include "lldb/Host/Host.h"
#include "lldb/Utility/Endian.h"
#include "lldb/Symbol/Function.h"
#include "lldb/Target/ABI.h"
#include "lldb/Target/ExecutionContext.h"
#include "lldb/Target/LanguageRuntime.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/StackFrame.h"
#include "lldb/Target/StackID.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/Thread.h"
#include "llvm/DebugInfo/DWARF/DWARFExpressionUnit.h"
#include "llvm/DebugInfo/DWARF/LowLevel/DWARFExpression.h"
#include "llvm/Support/ErrorExtras.h"

Go to the source code of this file.

Functions
static lldb::offset_t	GetOpcodeDataSize (const DataExtractor &data, const lldb::offset_t data_offset, const LocationAtom op, const DWARFExpression::Delegate *dwarf_cu)
	Return the length in bytes of the set of operands for op.
static const char *	DW_OP_value_to_name (uint32_t val)
static std::optional< Value >	EvaluateEntryValueInLanguageRuntime (EvalContext &eval_ctx, llvm::ArrayRef< uint8_t > entry_value, llvm::ArrayRef< uint8_t > &following)
	Asks the language runtime of the current function to evaluate DW_OP_entry_value(entry_value), possibly together with some of the following operations, which it consumes.
static llvm::Error	Evaluate_DW_OP_entry_value (EvalContext &eval_ctx, llvm::ArrayRef< uint8_t > subexpr)
static void	UpdateValueTypeFromLocationDescription (EvalContext &eval_ctx, LocationDescriptionKind kind, Value *value=nullptr)
	Adjust value's ValueType according to the kind of location description.
static llvm::Expected< lldb::addr_t >	ResolveLoadAddress (EvalContext &eval_ctx, const char *dw_op_type, lldb::addr_t file_addr, Address &so_addr, bool check_sectionoffset=false)
	Helper function to move common code used to resolve a file address and turn into a load address.
static Scalar	DerefSizeExtractDataHelper (uint8_t *addr_bytes, size_t size_addr_bytes, ByteOrder byte_order, size_t size)
	Helper function to load sized data from a uint8_t buffer.
static llvm::Error	Evaluate_DW_OP_deref (EvalContext &eval_ctx, LocationAtom opcode, unsigned size, size_t size_addr_bytes)
static std::optional< uint64_t >	BitsToBytes (uint64_t bit_size)
static uint8_t	GetBitMask (uint64_t bit_offset, lldb::ByteOrder byte_order)
static llvm::Error	AppendPieceToComposite (EvalContext &eval_ctx, const Value &piece, uint64_t piece_bit_size)
	Appends an eagerly materialized piece at the next composite bit offset.
static llvm::Error	Evaluate_DW_OP_piece (EvalContext &eval_ctx, uint64_t piece_byte_size)
static llvm::Error	Evaluate_DW_OP_convert (EvalContext &eval_ctx, uint64_t relative_die_offset)
static llvm::Error	Evaluate_DW_OP_form_tls_address (EvalContext &eval_ctx, LocationAtom opcode)
static llvm::Error	Evaluate_DW_OP_fbreg (EvalContext &eval_ctx, int64_t fbreg_offset)
static llvm::Error	Evaluate_DW_OP_call_frame_cfa (EvalContext &eval_ctx)
static llvm::Error	CheckScalarOperandsHaveSameType (const Scalar &lhs, const Scalar &rhs, LocationAtom opcode, size_t address_size)
static bool	IsPotentiallyGenericIntegerOperand (const Scalar &operand, size_t address_size)

Function Documentation

AppendPieceToComposite()

llvm::Error AppendPieceToComposite ( EvalContext & eval_ctx, const Value & piece, uint64_t piece_bit_size )

static

Appends an eagerly materialized piece at the next composite bit offset.

Definition at line 1153 of file DWARFExpression.cpp.

References bit, BitsToBytes(), lldb::eByteOrderBig, lldb::eByteOrderLittle, error(), lldb_private::Value::FileAddress, lldb_private::Scalar::GetAsMemoryData(), GetBitMask(), lldb_private::Value::GetBuffer(), lldb_private::WritableDataBuffer::GetBytes(), lldb_private::DataBufferHeap::GetByteSize(), lldb_private::Value::GetScalar(), lldb_private::Value::GetValueType(), lldb_private::Value::HostAddress, lldb_private::Value::Invalid, lldb_private::Value::LoadAddress, lldb_private::Value::ResizeData(), and lldb_private::Value::Scalar.

Referenced by lldb_private::DWARFExpression::Evaluate(), and Evaluate_DW_OP_piece().

BitsToBytes()

std::optional< uint64_t > BitsToBytes ( uint64_t bit_size )

static

Definition at line 1139 of file DWARFExpression.cpp.

Referenced by AppendPieceToComposite().

CheckScalarOperandsHaveSameType()

llvm::Error CheckScalarOperandsHaveSameType ( const Scalar & lhs, const Scalar & rhs, LocationAtom opcode, size_t address_size )

static

Definition at line 1526 of file DWARFExpression.cpp.

References DW_OP_value_to_name(), lldb_private::Scalar::e_int, lldb_private::Scalar::GetByteSize(), lldb_private::Scalar::GetType(), and lldb_private::Scalar::IsSigned().

Referenced by lldb_private::DWARFExpression::Evaluate().

DerefSizeExtractDataHelper()

Scalar DerefSizeExtractDataHelper ( uint8_t * addr_bytes, size_t size_addr_bytes, ByteOrder byte_order, size_t size )

static

Helper function to load sized data from a uint8_t buffer.

Parameters

addr_bytes	The buffer containing raw data.
size_addr_bytes	How large is the underlying raw data.
byte_order	What is the byte order of the underlying data.
size	How much of the underlying data we want to use.

Returns

The underlying data converted into a Scalar.

Definition at line 977 of file DWARFExpression.cpp.

References lldb_private::DataExtractor::GetAddress(), and lldb_private::DataExtractor::GetMaxU64().

Referenced by Evaluate_DW_OP_deref().

DW_OP_value_to_name()

const char * DW_OP_value_to_name ( uint32_t val )

static

Definition at line 460 of file DWARFExpression.cpp.

Referenced by CheckScalarOperandsHaveSameType(), lldb_private::DWARFExpression::Evaluate(), Evaluate_DW_OP_deref(), and lldb_private::DWARFExpression::GetLocation_DW_OP_addr().

Evaluate_DW_OP_call_frame_cfa()

llvm::Error Evaluate_DW_OP_call_frame_cfa ( EvalContext & eval_ctx )

static

Definition at line 1505 of file DWARFExpression.cpp.

References lldb_private::StackFrame::GetStackID(), LLDB_INVALID_ADDRESS, and lldb_private::Value::LoadAddress.

Referenced by lldb_private::DWARFExpression::Evaluate().

Evaluate_DW_OP_convert()

llvm::Error Evaluate_DW_OP_convert ( EvalContext & eval_ctx, uint64_t relative_die_offset )

static

Definition at line 1381 of file DWARFExpression.cpp.

References lldb_private::Scalar::e_float, lldb_private::Scalar::FloatPromote(), lldb_private::Scalar::GetAPFloat(), lldb_private::DWARFExpression::Delegate::GetDIEBitSizeAndEncoding(), lldb_private::Scalar::GetType(), and lldb_private::Scalar::TruncOrExtendTo().

Referenced by lldb_private::DWARFExpression::Evaluate().

Evaluate_DW_OP_deref()

llvm::Error Evaluate_DW_OP_deref ( EvalContext & eval_ctx, LocationAtom opcode, unsigned size, size_t size_addr_bytes )

static

Definition at line 988 of file DWARFExpression.cpp.

References DerefSizeExtractDataHelper(), DW_OP_value_to_name(), error(), lldb_private::Value::FileAddress, lldb_private::ObjectFile::GetByteOrder(), lldb_private::Process::GetByteOrder(), lldb_private::Value::HostAddress, lldb_private::Value::Invalid, lldb_private::Address::IsSectionOffset(), LLDB_INVALID_ADDRESS, lldb_private::Value::LoadAddress, lldb_private::Memory, lldb_private::Process::ReadMemory(), lldb_private::Target::ReadMemory(), ResolveLoadAddress(), lldb_private::Value::Scalar, and lldb_private::Scalar::TruncOrExtendTo().

Referenced by lldb_private::DWARFExpression::Evaluate().

Evaluate_DW_OP_entry_value()

llvm::Error Evaluate_DW_OP_entry_value ( EvalContext & eval_ctx, llvm::ArrayRef< uint8_t > subexpr )

static

Definition at line 716 of file DWARFExpression.cpp.

References lldb_private::DataExtractor::BytesLeft(), lldb_private::DWARFExpressionList::Evaluate(), lldb_private::Expressions, lldb_private::SymbolContext::function, lldb_private::Function::GetCallEdgeForReturnAddress(), lldb_private::CallEdge::GetCallee(), lldb_private::CallEdge::GetCallSiteParameters(), lldb_private::DataExtractor::GetData(), lldb_private::StackFrame::GetFrameIndex(), lldb_private::ExecutionContext::GetFramePtr(), lldb_private::Target::GetImages(), lldb_private::GetLog(), lldb_private::Function::GetName(), lldb_private::StackFrame::GetSymbolContext(), lldb_private::Function::GetTailCallingEdges(), lldb_private::ExecutionContext::GetTargetRef(), lldb_private::ExecutionContext::GetThreadPtr(), lldb_private::ExecutionContext::HasTargetScope(), LLDB_INVALID_ADDRESS, LLDB_LOG, lldb_private::CallSiteParameter::LocationInCaller, and lldb_private::ExecutionContext::SetFrameSP().

Referenced by lldb_private::DWARFExpression::Evaluate().

Evaluate_DW_OP_fbreg()

llvm::Error Evaluate_DW_OP_fbreg ( EvalContext & eval_ctx, int64_t fbreg_offset )

static

Definition at line 1488 of file DWARFExpression.cpp.

References lldb_private::StackFrame::GetFrameBaseValue(), and lldb_private::Value::LoadAddress.

Referenced by lldb_private::DWARFExpression::Evaluate().

Evaluate_DW_OP_form_tls_address()

llvm::Error Evaluate_DW_OP_form_tls_address ( EvalContext & eval_ctx, LocationAtom opcode )

static

Definition at line 1458 of file DWARFExpression.cpp.

References lldb_private::ExecutionContext::GetThreadPtr(), LLDB_INVALID_ADDRESS, and lldb_private::Value::LoadAddress.

Referenced by lldb_private::DWARFExpression::Evaluate().

Evaluate_DW_OP_piece()

llvm::Error Evaluate_DW_OP_piece ( EvalContext & eval_ctx, uint64_t piece_byte_size )

static

Definition at line 1256 of file DWARFExpression.cpp.

References AppendPieceToComposite(), lldb_private::Value::ConvertToLoadAddress(), error(), lldb_private::Scalar::ExtractBitfield(), lldb_private::Value::FileAddress, lldb_private::Value::GetBuffer(), lldb_private::WritableDataBuffer::GetBytes(), lldb_private::DataBufferHeap::GetByteSize(), lldb_private::Scalar::GetByteSize(), lldb_private::Value::GetScalar(), lldb_private::Value::GetValueType(), lldb_private::Value::HostAddress, lldb_private::Value::Invalid, LLDB_INVALID_ADDRESS, lldb_private::Value::LoadAddress, lldb_private::Memory, lldb_private::Target::ReadMemory(), lldb_private::Value::ResizeData(), lldb_private::Value::Scalar, lldb_private::Scalar::TruncOrExtendTo(), lldb_private::Scalar::ULongLong(), and UpdateValueTypeFromLocationDescription().

Referenced by lldb_private::DWARFExpression::Evaluate().

EvaluateEntryValueInLanguageRuntime()

std::optional< Value > EvaluateEntryValueInLanguageRuntime ( EvalContext & eval_ctx, llvm::ArrayRef< uint8_t > entry_value, llvm::ArrayRef< uint8_t > & following )

static

Asks the language runtime of the current function to evaluate DW_OP_entry_value(entry_value), possibly together with some of the following operations, which it consumes.

Definition at line 692 of file DWARFExpression.cpp.

References lldb_private::LanguageRuntime::EvaluateEntryValue(), lldb_private::SymbolContext::function, lldb_private::Function::GetLanguage(), lldb_private::Process::GetLanguageRuntime(), and lldb_private::StackFrame::GetSymbolContext().

Referenced by lldb_private::DWARFExpression::Evaluate().

GetBitMask()

uint8_t GetBitMask ( uint64_t bit_offset, lldb::ByteOrder byte_order )

static

Definition at line 1145 of file DWARFExpression.cpp.

References lldb::eByteOrderBig.

Referenced by AppendPieceToComposite().

GetOpcodeDataSize()

lldb::offset_t GetOpcodeDataSize ( const DataExtractor & data, const lldb::offset_t data_offset, const LocationAtom op, const DWARFExpression::Delegate * dwarf_cu )

static

Return the length in bytes of the set of operands for op.

No guarantees are made on the state of data after this call.

Definition at line 197 of file DWARFExpression.cpp.

References lldb_private::DataExtractor::GetAddressByteSize(), lldb_private::DWARFExpression::Delegate::GetAddressByteSize(), lldb_private::DataExtractor::GetU8(), lldb_private::DataExtractor::GetULEB128(), lldb_private::DWARFExpression::Delegate::GetVendorDWARFOpcodeSize(), LLDB_INVALID_OFFSET, and lldb_private::DataExtractor::Skip_LEB128().

Referenced by lldb_private::DWARFExpression::ContainsThreadLocalStorage(), lldb_private::DWARFExpression::GetLocation_DW_OP_addr(), lldb_private::DWARFExpression::IsImplicit(), lldb_private::DWARFExpression::LinkThreadLocalStorage(), and lldb_private::DWARFExpression::Update_DW_OP_addr().

IsPotentiallyGenericIntegerOperand()

bool IsPotentiallyGenericIntegerOperand ( const Scalar & operand, size_t address_size )

static

Definition at line 1578 of file DWARFExpression.cpp.

References lldb_private::Scalar::e_int, lldb_private::Scalar::GetByteSize(), and lldb_private::Scalar::GetType().

Referenced by lldb_private::DWARFExpression::Evaluate().

ResolveLoadAddress()

llvm::Expected< lldb::addr_t > ResolveLoadAddress ( EvalContext & eval_ctx, const char * dw_op_type, lldb::addr_t file_addr, Address & so_addr, bool check_sectionoffset = false )

static

Helper function to move common code used to resolve a file address and turn into a load address.

Parameters

eval_ctx	Evaluation context (provides exe_ctx and module_sp).
dw_op_type	C-style string used to vary the error output
file_addr	the file address we are trying to resolve and turn into a load address
so_addr	out parameter, will be set to load address or section offset
check_sectionoffset	bool which determines if having a section offset but not a load address is considerd a success

Returns

std::optional containing the load address if resolving and getting the load address succeed or an empty Optinal otherwise. If check_sectionoffset is true we consider LLDB_INVALID_ADDRESS a success if so_addr.IsSectionOffset() is true.

Definition at line 951 of file DWARFExpression.cpp.

References lldb_private::Address::GetLoadAddress(), lldb_private::Address::IsSectionOffset(), and LLDB_INVALID_ADDRESS.

Referenced by ProcessMachCore::DoGetMemoryRegionInfo(), and Evaluate_DW_OP_deref().

UpdateValueTypeFromLocationDescription()

void UpdateValueTypeFromLocationDescription ( EvalContext & eval_ctx, LocationDescriptionKind kind, Value * value = nullptr )

static

Adjust value's ValueType according to the kind of location description.

Definition at line 902 of file DWARFExpression.cpp.

References Empty, lldb_private::Expressions, lldb_private::GetLog(), lldb_private::DWARFExpression::Delegate::GetVersion(), LLDB_LOGF, lldb_private::Value::LoadAddress, lldb_private::Memory, and lldb_private::Value::Scalar.

Referenced by lldb_private::DWARFExpression::Evaluate(), and Evaluate_DW_OP_piece().