InstrProfWriter.cpp [plain text]
#include "llvm/ProfileData/InstrProfWriter.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Support/EndianStream.h"
#include "llvm/Support/OnDiskHashTable.h"
using namespace llvm;
namespace {
static support::endianness ValueProfDataEndianness = support::little;
class InstrProfRecordTrait {
public:
typedef StringRef key_type;
typedef StringRef key_type_ref;
typedef const InstrProfWriter::ProfilingData *const data_type;
typedef const InstrProfWriter::ProfilingData *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();
LE.write<offset_type>(N);
offset_type M = 0;
for (const auto &ProfileData : *V) {
const InstrProfRecord &ProfRecord = ProfileData.second;
M += sizeof(uint64_t); M += sizeof(uint64_t); M += ProfRecord.Counts.size() * sizeof(uint64_t);
M += IndexedInstrProf::ValueProfData::getSize(ProfileData.second);
}
LE.write<offset_type>(M);
return std::make_pair(N, M);
}
static void EmitKey(raw_ostream &Out, key_type_ref K, offset_type N){
Out.write(K.data(), 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 (const auto &ProfileData : *V) {
const InstrProfRecord &ProfRecord = ProfileData.second;
LE.write<uint64_t>(ProfileData.first); LE.write<uint64_t>(ProfRecord.Counts.size());
for (uint64_t I : ProfRecord.Counts)
LE.write<uint64_t>(I);
std::unique_ptr<IndexedInstrProf::ValueProfData> VDataPtr =
IndexedInstrProf::ValueProfData::serializeFrom(ProfileData.second);
uint32_t S = VDataPtr->getSize();
VDataPtr->swapBytesFromHost(ValueProfDataEndianness);
Out.write((const char *)VDataPtr.get(), S);
}
}
};
}
static std::error_code combineInstrProfRecords(InstrProfRecord &Dest,
InstrProfRecord &Source,
uint64_t &MaxFunctionCount) {
if (Dest.Counts.size() != Source.Counts.size())
return instrprof_error::count_mismatch;
for (size_t I = 0, E = Source.Counts.size(); I < E; ++I) {
if (Dest.Counts[I] + Source.Counts[I] < Dest.Counts[I])
return instrprof_error::counter_overflow;
Dest.Counts[I] += Source.Counts[I];
}
for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind) {
if (std::error_code EC = Dest.mergeValueProfData(Kind, Source))
return EC;
}
if (Dest.Counts[0] > MaxFunctionCount)
MaxFunctionCount = Dest.Counts[0];
return instrprof_error::success;
}
void InstrProfWriter::setValueProfDataEndianness(
support::endianness Endianness) {
ValueProfDataEndianness = Endianness;
}
void InstrProfWriter::updateStringTableReferences(InstrProfRecord &I) {
I.updateStrings(&StringTable);
}
std::error_code InstrProfWriter::addRecord(InstrProfRecord &&I) {
updateStringTableReferences(I);
auto &ProfileDataMap = FunctionData[I.Name];
auto Where = ProfileDataMap.find(I.Hash);
if (Where == ProfileDataMap.end()) {
ProfileDataMap[I.Hash] = I;
if (I.Counts[0] > MaxFunctionCount)
MaxFunctionCount = I.Counts[0];
return instrprof_error::success;
}
return combineInstrProfRecords(Where->second, I, MaxFunctionCount);
}
std::pair<uint64_t, uint64_t> InstrProfWriter::writeImpl(raw_ostream &OS) {
OnDiskChainedHashTableGenerator<InstrProfRecordTrait> Generator;
for (const auto &I : FunctionData)
Generator.insert(I.getKey(), &I.getValue());
using namespace llvm::support;
endian::Writer<little> LE(OS);
IndexedInstrProf::Header Header;
Header.Magic = IndexedInstrProf::Magic;
Header.Version = IndexedInstrProf::Version;
Header.MaxFunctionCount = MaxFunctionCount;
Header.HashType = static_cast<uint64_t>(IndexedInstrProf::HashType);
Header.HashOffset = 0;
int N = sizeof(IndexedInstrProf::Header) / sizeof(uint64_t);
for (int I = 0; I < N - 1; I++)
LE.write<uint64_t>(reinterpret_cast<uint64_t *>(&Header)[I]);
uint64_t HashTableStartLoc = OS.tell();
LE.write<uint64_t>(0);
uint64_t HashTableStart = Generator.Emit(OS);
return std::make_pair(HashTableStartLoc, HashTableStart);
}
void InstrProfWriter::write(raw_fd_ostream &OS) {
auto TableStart = writeImpl(OS);
using namespace support;
OS.seek(TableStart.first);
endian::Writer<little>(OS).write<uint64_t>(TableStart.second);
}
std::unique_ptr<MemoryBuffer> InstrProfWriter::writeBuffer() {
std::string Data;
llvm::raw_string_ostream OS(Data);
auto TableStart = writeImpl(OS);
OS.flush();
using namespace support;
uint64_t Bytes = endian::byte_swap<uint64_t, little>(TableStart.second);
Data.replace(TableStart.first, sizeof(uint64_t), (const char *)&Bytes,
sizeof(uint64_t));
return MemoryBuffer::getMemBufferCopy(Data);
}