blob: 83c41d93bb1814f6ca305dddaa60f1486bf2152a [file] [log] [blame]
//=-- InstrProfWriter.cpp - Instrumented profiling writer -------------------=//
// The LLVM Compiler Infrastructure
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
// This file contains support for writing profiling data for clang's
// instrumentation based PGO and coverage.
#include "llvm/ProfileData/InstrProfWriter.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Support/EndianStream.h"
#include "llvm/Support/OnDiskHashTable.h"
#include "InstrProfIndexed.h"
using namespace llvm;
namespace {
class InstrProfRecordTrait {
typedef StringRef key_type;
typedef StringRef key_type_ref;
typedef const InstrProfWriter::CounterData *const data_type;
typedef const InstrProfWriter::CounterData *const data_type_ref;
typedef uint64_t hash_value_type;
typedef uint64_t offset_type;
static hash_value_type ComputeHash(key_type_ref K) {
return IndexedInstrProf::ComputeHash(IndexedInstrProf::HashType, K);
static std::pair<offset_type, offset_type>
EmitKeyDataLength(raw_ostream &Out, key_type_ref K, data_type_ref V) {
using namespace llvm::support;
endian::Writer<little> LE(Out);
offset_type N = K.size();
offset_type M = (1 + V->Counts.size()) * sizeof(uint64_t);
return std::make_pair(N, M);
static void EmitKey(raw_ostream &Out, key_type_ref K, offset_type N){
Out.write(, N);
static void EmitData(raw_ostream &Out, key_type_ref, data_type_ref V,
offset_type) {
using namespace llvm::support;
endian::Writer<little> LE(Out);
for (uint64_t I : V->Counts)
error_code InstrProfWriter::addFunctionCounts(StringRef FunctionName,
uint64_t FunctionHash,
ArrayRef<uint64_t> Counters) {
auto Where = FunctionData.find(FunctionName);
if (Where == FunctionData.end()) {
// If this is the first time we've seen this function, just add it.
auto &Data = FunctionData[FunctionName];
Data.Hash = FunctionHash;
Data.Counts = Counters;
return instrprof_error::success;
auto &Data = Where->getValue();
// We can only add to existing functions if they match, so we check the hash
// and number of counters.
if (Data.Hash != FunctionHash)
return instrprof_error::hash_mismatch;
if (Data.Counts.size() != Counters.size())
return instrprof_error::count_mismatch;
// These match, add up the counters.
for (size_t I = 0, E = Counters.size(); I < E; ++I) {
if (Data.Counts[I] + Counters[I] < Data.Counts[I])
return instrprof_error::counter_overflow;
Data.Counts[I] += Counters[I];
return instrprof_error::success;
void InstrProfWriter::write(raw_fd_ostream &OS) {
OnDiskChainedHashTableGenerator<InstrProfRecordTrait> Generator;
uint64_t MaxFunctionCount = 0;
// Populate the hash table generator.
for (const auto &I : FunctionData) {
Generator.insert(I.getKey(), &I.getValue());
if (I.getValue().Counts[0] > MaxFunctionCount)
MaxFunctionCount = I.getValue().Counts[0];
using namespace llvm::support;
endian::Writer<little> LE(OS);
// Write the header.
// Save a space to write the hash table start location.
uint64_t HashTableStartLoc = OS.tell();
// Write the hash table.
uint64_t HashTableStart = Generator.Emit(OS);
// Go back and fill in the hash table start.;