Inline information stores the name of the inline function along with an array of address ranges. More...

#include "llvm/DebugInfo/GSYM/InlineInfo.h"

Public Types
using	InlineArray = std::vector<const InlineInfo *>

Public Member Functions
	InlineInfo ()=default
void	clear ()
bool	isValid () const
LLVM_ABI std::optional< InlineArray >	getInlineStack (uint64_t Addr) const
	Lookup an address in the InlineInfo object.
LLVM_ABI llvm::Error	encode (FileWriter &O, uint64_t BaseAddr) const
	Encode this InlineInfo object into FileWriter stream.
LLVM_ABI bool	operator< (const InlineInfo &RHS) const
	Compare InlineInfo objects.

Static Public Member Functions
static LLVM_ABI llvm::Error	lookup (const GsymReader &GR, DataExtractor &Data, uint64_t BaseAddr, uint64_t Addr, SourceLocations &SrcLocs)
	Lookup a single address within the inline info data.
static LLVM_ABI llvm::Expected< InlineInfo >	decode (DataExtractor &Data, uint64_t BaseAddr)
	Decode an InlineInfo object from a binary data stream.

Public Attributes
uint32_t	Name = 0
	String table offset in the string table.
uint32_t	CallFile = 0
	1 based file index in the file table.
uint32_t	CallLine = 0
	Source line number.
AddressRanges	Ranges
std::vector< InlineInfo >	Children

Detailed Description

Inline information stores the name of the inline function along with an array of address ranges.

It also stores the call file and call line that called this inline function. This allows us to unwind inline call stacks back to the inline or concrete function that called this function. Inlined functions contained in this function are stored in the "Children" variable. All address ranges must be sorted and all address ranges of all children must be contained in the ranges of this function. Any clients that encode information will need to ensure the ranges are all contined correctly or lookups could fail. Add ranges in these objects must be contained in the top level FunctionInfo address ranges as well.

ENCODING

When saved to disk, the inline info encodes all ranges to be relative to a parent address range. This will be the FunctionInfo's start address if the InlineInfo is directly contained in a FunctionInfo, or a the start address of the containing parent InlineInfo's first "Ranges" member. This allows address ranges to be efficiently encoded using ULEB128 encodings as we encode the offset and size of each range instead of full addresses. This also makes any encoded addresses easy to relocate as we just need to relocate the FunctionInfo's start address.

The AddressRanges member "Ranges" is encoded using an appropriate base address as described above.
UINT8 boolean value that specifies if the InlineInfo object has children.
UINT32 string table offset that points to the name of the inline function.
ULEB128 integer that specifies the file of the call site that called this function.
ULEB128 integer that specifies the source line of the call site that called this function.
if this object has children, enocode each child InlineInfo using the the first address range's start address as the base address.

Definition at line 60 of file InlineInfo.h.

Member Typedef Documentation

◆ InlineArray

using llvm::gsym::InlineInfo::InlineArray = std::vector<const InlineInfo *>

Definition at line 77 of file InlineInfo.h.

Constructor & Destructor Documentation

◆ InlineInfo()

llvm::gsym::InlineInfo::InlineInfo ( )

default

Referenced by operator<().

Member Function Documentation

◆ clear()

void llvm::gsym::InlineInfo::clear ( )

inline

Definition at line 68 of file InlineInfo.h.

References CallFile, CallLine, Children, Name, and Ranges.

◆ decode()

llvm::Expected< InlineInfo > InlineInfo::decode	(	DataExtractor &	Data,
		uint64_t	BaseAddr )

static

Decode an InlineInfo object from a binary data stream.

Parameters

Data	The binary stream to read the data from. This object must have the data for the InlineInfo object starting at offset zero. The data can contain more data than needed.
BaseAddr	The base address to use when decoding all address ranges. This will be the FunctionInfo's start address if this object is directly contained in a FunctionInfo object, or the start address of the first address range in an InlineInfo object of this object is a child of another InlineInfo object.

Returns: An InlineInfo or an error describing the issue that was encountered during decoding.

Definition at line 222 of file InlineInfo.cpp.

References llvm::Data, and llvm::Offset.

Referenced by llvm::gsym::FunctionInfo::decode().

◆ encode()

llvm::Error InlineInfo::encode	(	FileWriter &	O,
		uint64_t	BaseAddr ) const

Encode this InlineInfo object into FileWriter stream.

Parameters

O	The binary stream to write the data to at the current file position.
BaseAddr	The base address to use when encoding all address ranges. This will be the FunctionInfo's start address if this object is directly contained in a FunctionInfo object, or the start address of the first address range in an InlineInfo object of this object is a child of another InlineInfo object.

Returns: An error object that indicates success or failure or the encoding process.

Definition at line 228 of file InlineInfo.cpp.

References CallFile, CallLine, Children, llvm::createStringError(), llvm::gsym::encodeRanges(), isValid(), Name, Ranges, and llvm::Error::success().

◆ getInlineStack()

std::optional< InlineInfo::InlineArray > InlineInfo::getInlineStack ( uint64_t Addr ) const

Lookup an address in the InlineInfo object.

This function is used to symbolicate an inline call stack and can turn one address in the program into one or more inline call stacks and have the stack trace show the original call site from non-inlined code.

Parameters

Addr	the address to lookup

Returns: optional vector of InlineInfo objects that describe the inline call stack for a given address, false otherwise.

Definition at line 56 of file InlineInfo.cpp.

References getInlineStack(), and getInlineStackHelper().

Referenced by getInlineStack().

◆ isValid()

bool llvm::gsym::InlineInfo::isValid ( ) const

inline

Definition at line 75 of file InlineInfo.h.

References Ranges.

Referenced by encode().

◆ lookup()

llvm::Error InlineInfo::lookup	(	const GsymReader &	GR,
		DataExtractor &	Data,
		uint64_t	BaseAddr,
		uint64_t	Addr,
		SourceLocations &	SrcLocs )

static

Lookup a single address within the inline info data.

Clients have the option to decode an entire InlineInfo object (using InlineInfo::decode() ) or just find the matching inline info using this function. The benefit of using this function is that only the information needed for the lookup will be extracted, other info can be skipped and parsing can stop as soon as the deepest match is found. This allows symbolication tools to be fast and efficient and avoid allocation costs when doing lookups.

This function will augment the SourceLocations array SrcLocs with any inline information that pertains to Addr. If no inline information exists for Addr, then SrcLocs will be left untouched. If there is inline information for Addr, then SrcLocs will be modifiied to contain the deepest most inline function's SourceLocation at index zero in the array and proceed up the concrete function source file and line at the end of the array.

Parameters

GR	The GSYM reader that contains the string and file table that will be used to fill in the source locations.
Data	The binary stream to read the data from. This object must have the data for the LineTable object starting at offset zero. The data can contain more data than needed.
BaseAddr	The base address to use when decoding the line table. This will be the FunctionInfo's start address and will be used to decode the correct addresses for the inline information.
Addr	The address to lookup.
SrcLocs	The inline source locations that matches Addr. This array must be initialized with the matching line entry from the line table upon entry. The name of the concrete function must be supplied since it will get pushed to the last SourceLocation entry and the inline information will fill in the source file and line from the inline information.

Returns: An error if the inline information is corrupt, or Error::success() for all other cases, even when no information is added to SrcLocs.

Definition at line 159 of file InlineInfo.cpp.

References llvm::Data, lookup(), llvm::Offset, and llvm::Error::success().

Referenced by llvm::gsym::FunctionInfo::lookup(), and lookup().

◆ operator<()

bool InlineInfo::operator< ( const InlineInfo & RHS ) const

Compare InlineInfo objects.

When comparing InlineInfo objects the item with the most inline functions wins. If we have two FunctionInfo objects that both have the same address range and both have valid InlineInfo objects, we want the one with the most inline functions to win so we save the most information possible to the GSYM file. We have seen cases where LTO messes up the inline function information for the same address range, so this helps ensure we get the most descriptive information we can for an address range.

Definition at line 274 of file InlineInfo.cpp.

References GetTotalNumChildren(), and InlineInfo().

Member Data Documentation

◆ CallFile

uint32_t llvm::gsym::InlineInfo::CallFile = 0

1 based file index in the file table.

Definition at line 63 of file InlineInfo.h.

Referenced by clear(), and encode().

◆ CallLine

uint32_t llvm::gsym::InlineInfo::CallLine = 0

Source line number.

Definition at line 64 of file InlineInfo.h.

Referenced by clear(), and encode().

◆ Children

std::vector<InlineInfo> llvm::gsym::InlineInfo::Children

Definition at line 66 of file InlineInfo.h.

Referenced by clear(), encode(), and parseInlineInfo().

◆ Name

uint32_t llvm::gsym::InlineInfo::Name = 0

String table offset in the string table.

Definition at line 62 of file InlineInfo.h.

Referenced by clear(), and encode().

◆ Ranges

AddressRanges llvm::gsym::InlineInfo::Ranges

Definition at line 65 of file InlineInfo.h.

Referenced by clear(), encode(), isValid(), and parseInlineInfo().

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

include/llvm/DebugInfo/GSYM/InlineInfo.h
lib/DebugInfo/GSYM/InlineInfo.cpp

Public Types

Public Member Functions

Static Public Member Functions

Public Attributes

Detailed Description

Member Typedef Documentation

◆ InlineArray

Constructor & Destructor Documentation

◆ InlineInfo()

Member Function Documentation

◆ clear()

◆ decode()

◆ encode()

◆ getInlineStack()

◆ isValid()

◆ lookup()

◆ operator<()

Member Data Documentation

◆ CallFile

◆ CallLine

◆ Children

◆ Name

◆ Ranges