class SampleProfileReaderGCC

Declaration

class SampleProfileReaderGCC : public SampleProfileReader { /* full declaration omitted */ };

Description

Sample-based profile reader. Each profile contains sample counts for all the functions executed. Inside each function, statements are annotated with the collected samples on all the instructions associated with that statement. For this to produce meaningful data, the program needs to be compiled with some debug information (at minimum, line numbers: -gline-tables-only). Otherwise, it will be impossible to match IR instructions to the line numbers collected by the profiler. From the profile file, we are interested in collecting the following information: * A list of functions included in the profile (mangled names). * For each function F: 1. The total number of samples collected in F. 2. The samples collected at each line in F. To provide some protection against source code shuffling, line numbers should be relative to the start of the function. The reader supports two file formats: text and binary. The text format is useful for debugging and testing, while the binary format is more compact and I/O efficient. They can both be used interchangeably.

Declared at: llvm/include/llvm/ProfileData/SampleProfReader.h:691

Inherits from: SampleProfileReader

Member Variables

protected llvm::GCOVBuffer GcovBuffer
GCOV buffer containing the profile.
protected std::vector<std::string> Names
Function names in this profile.
protected static const uint32_t GCOVTagAFDOFileNames = 2852126720U
GCOV tags used to separate sections in the profile file.
protected static const uint32_t GCOVTagAFDOFunction = 2885681152U

Inherited from SampleProfileReader:

protected Profiles
protected Ctx
protected Buffer
protected Summary
protected Remapper
protected Format = SPF_None

Method Overview

Inherited from SampleProfileReader:

Methods

SampleProfileReaderGCC(
    std::unique_ptr<MemoryBuffer> B,
    llvm::LLVMContext& C)

Declared at: llvm/include/llvm/ProfileData/SampleProfReader.h:693

Parameters

std::unique_ptr<MemoryBuffer> B
llvm::LLVMContext& C

static bool hasFormat(
    const llvm::MemoryBuffer& Buffer)

Description

Return true if \p Buffer is in the format supported by this class.

Declared at: llvm/include/llvm/ProfileData/SampleProfReader.h:704

Parameters

const llvm::MemoryBuffer& Buffer

std::error_code readFunctionProfiles()

Declared at: llvm/include/llvm/ProfileData/SampleProfReader.h:710

std::error_code readHeader()

Description

Read and validate the file header.

Declared at: llvm/include/llvm/ProfileData/SampleProfReader.h:698

std::error_code readImpl()

Description

Read sample profiles from the associated file.

Declared at: llvm/include/llvm/ProfileData/SampleProfReader.h:701

std::error_code readNameTable()

Declared at: llvm/include/llvm/ProfileData/SampleProfReader.h:707

template <typename T>
ErrorOr<T> readNumber()

Declared at: llvm/include/llvm/ProfileData/SampleProfReader.h:712

Templates

T

std::error_code readOneFunctionProfile(
    const llvm::sampleprof::InlineCallStack&
        InlineStack,
    bool Update,
    uint32_t Offset)

Declared at: llvm/include/llvm/ProfileData/SampleProfReader.h:708

Parameters

const llvm::sampleprof::InlineCallStack& InlineStack
bool Update
uint32_t Offset

std::error_code readSectionTag(uint32_t Expected)

Description

Read the section tag and check that it's the same as \p Expected.

Declared at: llvm/include/llvm/ProfileData/SampleProfReader.h:716

Parameters

uint32_t Expected

ErrorOr<llvm::StringRef> readString()

Declared at: llvm/include/llvm/ProfileData/SampleProfReader.h:713

std::error_code skipNextWord()

Declared at: llvm/include/llvm/ProfileData/SampleProfReader.h:711