class UnwindRow

Declaration

class UnwindRow { /* full declaration omitted */ };

Description

A class that represents a single row in the unwind table that is decoded by parsing the DWARF Call Frame Information opcodes. The row consists of an optional address, the rule to unwind the CFA and all rules to unwind any registers. If the address doesn't have a value, this row represents the initial instructions for a CIE. If the address has a value the UnwindRow represents a row in the UnwindTable for a FDE. The address is the first address for which the CFA location and register rules are valid within a function. UnwindRow objects are created by parsing opcodes in the DWARF Call Frame Information and UnwindRow objects are lazily populated and pushed onto a stack in the UnwindTable when evaluating this state machine. Accessors are needed for the address, CFA value, and register locations as the opcodes encode a state machine that produces a sorted array of UnwindRow objects

Declared at: llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h:253

Member Variables

private Optional<uint64_t> Address
Address for row in FDE, invalid for CIE.
private llvm::dwarf::UnwindLocation CFAValue
How to unwind the Call Frame Address (CFA).
private llvm::dwarf::RegisterLocations RegLocs
How to unwind all registers in this list.

Method Overview

Methods

UnwindRow()

Declared at: llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h:261

void dump(llvm::raw_ostream& OS,
          const llvm::MCRegisterInfo* MRI,
          bool IsEH,
          unsigned int IndentLevel = 0) const

Description

Dump the UnwindRow to the stream.

Declared at: llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h:304

Parameters

llvm::raw_ostream& OS
the stream to use for output.
const llvm::MCRegisterInfo* MRI
register information that helps emit register names insteead of raw register numbers.
bool IsEH
true if the DWARF Call Frame Information is from .eh_frame instead of from .debug_frame. This is needed for register number conversion because some register numbers differ between the two sections for certain architectures like x86.
unsigned int IndentLevel = 0
specify the indent level as an integer. The UnwindRow will be output to the stream preceded by 2 * IndentLevel number of spaces.

uint64_t getAddress() const

Description

Get the address for this row. Clients should only call this function after verifying it has a valid address with a call to

Declared at: llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h:270

llvm::dwarf::UnwindLocation& getCFAValue()

Declared at: llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h:285

const llvm::dwarf::UnwindLocation& getCFAValue()
    const

Declared at: llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h:286

llvm::dwarf::RegisterLocations&
getRegisterLocations()

Declared at: llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h:287

const llvm::dwarf::RegisterLocations&
getRegisterLocations() const

Declared at: llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h:288

bool hasAddress() const

Description

Returns true if the address is valid in this object.

Declared at: llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h:264

void setAddress(uint64_t Addr)

Description

Set the address for this UnwindRow. The address represents the first address for which the CFAValue and RegLocs are valid within a function.

Declared at: llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h:276

Parameters

uint64_t Addr

void slideAddress(uint64_t Offset)

Description

Offset the address for this UnwindRow. The address represents the first address for which the CFAValue and RegLocs are valid within a function. Clients must ensure that this object already has an address (

Declared at: llvm/include/llvm/DebugInfo/DWARF/DWARFDebugFrame.h:284

Parameters

uint64_t Offset