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llvm-for-llvmta/lib/ProfileData/InstrProfReader.cpp

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2022-04-25 10:02:23 +02:00
//===- InstrProfReader.cpp - Instrumented profiling reader ----------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file contains support for reading profiling data for clang's
// instrumentation based PGO and coverage.
//
//===----------------------------------------------------------------------===//
#include "llvm/ProfileData/InstrProfReader.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/IR/ProfileSummary.h"
#include "llvm/ProfileData/InstrProf.h"
#include "llvm/ProfileData/ProfileCommon.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/ErrorOr.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/SymbolRemappingReader.h"
#include "llvm/Support/SwapByteOrder.h"
#include <algorithm>
#include <cctype>
#include <cstddef>
#include <cstdint>
#include <limits>
#include <memory>
#include <system_error>
#include <utility>
#include <vector>
using namespace llvm;
static Expected<std::unique_ptr<MemoryBuffer>>
setupMemoryBuffer(const Twine &Path) {
ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
MemoryBuffer::getFileOrSTDIN(Path);
if (std::error_code EC = BufferOrErr.getError())
return errorCodeToError(EC);
return std::move(BufferOrErr.get());
}
static Error initializeReader(InstrProfReader &Reader) {
return Reader.readHeader();
}
Expected<std::unique_ptr<InstrProfReader>>
InstrProfReader::create(const Twine &Path) {
// Set up the buffer to read.
auto BufferOrError = setupMemoryBuffer(Path);
if (Error E = BufferOrError.takeError())
return std::move(E);
return InstrProfReader::create(std::move(BufferOrError.get()));
}
Expected<std::unique_ptr<InstrProfReader>>
InstrProfReader::create(std::unique_ptr<MemoryBuffer> Buffer) {
// Sanity check the buffer.
if (uint64_t(Buffer->getBufferSize()) > std::numeric_limits<uint64_t>::max())
return make_error<InstrProfError>(instrprof_error::too_large);
if (Buffer->getBufferSize() == 0)
return make_error<InstrProfError>(instrprof_error::empty_raw_profile);
std::unique_ptr<InstrProfReader> Result;
// Create the reader.
if (IndexedInstrProfReader::hasFormat(*Buffer))
Result.reset(new IndexedInstrProfReader(std::move(Buffer)));
else if (RawInstrProfReader64::hasFormat(*Buffer))
Result.reset(new RawInstrProfReader64(std::move(Buffer)));
else if (RawInstrProfReader32::hasFormat(*Buffer))
Result.reset(new RawInstrProfReader32(std::move(Buffer)));
else if (TextInstrProfReader::hasFormat(*Buffer))
Result.reset(new TextInstrProfReader(std::move(Buffer)));
else
return make_error<InstrProfError>(instrprof_error::unrecognized_format);
// Initialize the reader and return the result.
if (Error E = initializeReader(*Result))
return std::move(E);
return std::move(Result);
}
Expected<std::unique_ptr<IndexedInstrProfReader>>
IndexedInstrProfReader::create(const Twine &Path, const Twine &RemappingPath) {
// Set up the buffer to read.
auto BufferOrError = setupMemoryBuffer(Path);
if (Error E = BufferOrError.takeError())
return std::move(E);
// Set up the remapping buffer if requested.
std::unique_ptr<MemoryBuffer> RemappingBuffer;
std::string RemappingPathStr = RemappingPath.str();
if (!RemappingPathStr.empty()) {
auto RemappingBufferOrError = setupMemoryBuffer(RemappingPathStr);
if (Error E = RemappingBufferOrError.takeError())
return std::move(E);
RemappingBuffer = std::move(RemappingBufferOrError.get());
}
return IndexedInstrProfReader::create(std::move(BufferOrError.get()),
std::move(RemappingBuffer));
}
Expected<std::unique_ptr<IndexedInstrProfReader>>
IndexedInstrProfReader::create(std::unique_ptr<MemoryBuffer> Buffer,
std::unique_ptr<MemoryBuffer> RemappingBuffer) {
// Sanity check the buffer.
if (uint64_t(Buffer->getBufferSize()) > std::numeric_limits<uint64_t>::max())
return make_error<InstrProfError>(instrprof_error::too_large);
// Create the reader.
if (!IndexedInstrProfReader::hasFormat(*Buffer))
return make_error<InstrProfError>(instrprof_error::bad_magic);
auto Result = std::make_unique<IndexedInstrProfReader>(
std::move(Buffer), std::move(RemappingBuffer));
// Initialize the reader and return the result.
if (Error E = initializeReader(*Result))
return std::move(E);
return std::move(Result);
}
void InstrProfIterator::Increment() {
if (auto E = Reader->readNextRecord(Record)) {
// Handle errors in the reader.
InstrProfError::take(std::move(E));
*this = InstrProfIterator();
}
}
bool TextInstrProfReader::hasFormat(const MemoryBuffer &Buffer) {
// Verify that this really looks like plain ASCII text by checking a
// 'reasonable' number of characters (up to profile magic size).
size_t count = std::min(Buffer.getBufferSize(), sizeof(uint64_t));
StringRef buffer = Buffer.getBufferStart();
return count == 0 ||
std::all_of(buffer.begin(), buffer.begin() + count,
[](char c) { return isPrint(c) || isSpace(c); });
}
// Read the profile variant flag from the header: ":FE" means this is a FE
// generated profile. ":IR" means this is an IR level profile. Other strings
// with a leading ':' will be reported an error format.
Error TextInstrProfReader::readHeader() {
Symtab.reset(new InstrProfSymtab());
bool IsIRInstr = false;
bool IsEntryFirst = false;
bool IsCS = false;
while (Line->startswith(":")) {
StringRef Str = Line->substr(1);
if (Str.equals_lower("ir"))
IsIRInstr = true;
else if (Str.equals_lower("fe"))
IsIRInstr = false;
else if (Str.equals_lower("csir")) {
IsIRInstr = true;
IsCS = true;
} else if (Str.equals_lower("entry_first"))
IsEntryFirst = true;
else if (Str.equals_lower("not_entry_first"))
IsEntryFirst = false;
else
return error(instrprof_error::bad_header);
++Line;
}
IsIRLevelProfile = IsIRInstr;
InstrEntryBBEnabled = IsEntryFirst;
HasCSIRLevelProfile = IsCS;
return success();
}
Error
TextInstrProfReader::readValueProfileData(InstrProfRecord &Record) {
#define CHECK_LINE_END(Line) \
if (Line.is_at_end()) \
return error(instrprof_error::truncated);
#define READ_NUM(Str, Dst) \
if ((Str).getAsInteger(10, (Dst))) \
return error(instrprof_error::malformed);
#define VP_READ_ADVANCE(Val) \
CHECK_LINE_END(Line); \
uint32_t Val; \
READ_NUM((*Line), (Val)); \
Line++;
if (Line.is_at_end())
return success();
uint32_t NumValueKinds;
if (Line->getAsInteger(10, NumValueKinds)) {
// No value profile data
return success();
}
if (NumValueKinds == 0 || NumValueKinds > IPVK_Last + 1)
return error(instrprof_error::malformed);
Line++;
for (uint32_t VK = 0; VK < NumValueKinds; VK++) {
VP_READ_ADVANCE(ValueKind);
if (ValueKind > IPVK_Last)
return error(instrprof_error::malformed);
VP_READ_ADVANCE(NumValueSites);
if (!NumValueSites)
continue;
Record.reserveSites(VK, NumValueSites);
for (uint32_t S = 0; S < NumValueSites; S++) {
VP_READ_ADVANCE(NumValueData);
std::vector<InstrProfValueData> CurrentValues;
for (uint32_t V = 0; V < NumValueData; V++) {
CHECK_LINE_END(Line);
std::pair<StringRef, StringRef> VD = Line->rsplit(':');
uint64_t TakenCount, Value;
if (ValueKind == IPVK_IndirectCallTarget) {
if (InstrProfSymtab::isExternalSymbol(VD.first)) {
Value = 0;
} else {
if (Error E = Symtab->addFuncName(VD.first))
return E;
Value = IndexedInstrProf::ComputeHash(VD.first);
}
} else {
READ_NUM(VD.first, Value);
}
READ_NUM(VD.second, TakenCount);
CurrentValues.push_back({Value, TakenCount});
Line++;
}
Record.addValueData(ValueKind, S, CurrentValues.data(), NumValueData,
nullptr);
}
}
return success();
#undef CHECK_LINE_END
#undef READ_NUM
#undef VP_READ_ADVANCE
}
Error TextInstrProfReader::readNextRecord(NamedInstrProfRecord &Record) {
// Skip empty lines and comments.
while (!Line.is_at_end() && (Line->empty() || Line->startswith("#")))
++Line;
// If we hit EOF while looking for a name, we're done.
if (Line.is_at_end()) {
return error(instrprof_error::eof);
}
// Read the function name.
Record.Name = *Line++;
if (Error E = Symtab->addFuncName(Record.Name))
return error(std::move(E));
// Read the function hash.
if (Line.is_at_end())
return error(instrprof_error::truncated);
if ((Line++)->getAsInteger(0, Record.Hash))
return error(instrprof_error::malformed);
// Read the number of counters.
uint64_t NumCounters;
if (Line.is_at_end())
return error(instrprof_error::truncated);
if ((Line++)->getAsInteger(10, NumCounters))
return error(instrprof_error::malformed);
if (NumCounters == 0)
return error(instrprof_error::malformed);
// Read each counter and fill our internal storage with the values.
Record.Clear();
Record.Counts.reserve(NumCounters);
for (uint64_t I = 0; I < NumCounters; ++I) {
if (Line.is_at_end())
return error(instrprof_error::truncated);
uint64_t Count;
if ((Line++)->getAsInteger(10, Count))
return error(instrprof_error::malformed);
Record.Counts.push_back(Count);
}
// Check if value profile data exists and read it if so.
if (Error E = readValueProfileData(Record))
return error(std::move(E));
return success();
}
template <class IntPtrT>
bool RawInstrProfReader<IntPtrT>::hasFormat(const MemoryBuffer &DataBuffer) {
if (DataBuffer.getBufferSize() < sizeof(uint64_t))
return false;
uint64_t Magic =
*reinterpret_cast<const uint64_t *>(DataBuffer.getBufferStart());
return RawInstrProf::getMagic<IntPtrT>() == Magic ||
sys::getSwappedBytes(RawInstrProf::getMagic<IntPtrT>()) == Magic;
}
template <class IntPtrT>
Error RawInstrProfReader<IntPtrT>::readHeader() {
if (!hasFormat(*DataBuffer))
return error(instrprof_error::bad_magic);
if (DataBuffer->getBufferSize() < sizeof(RawInstrProf::Header))
return error(instrprof_error::bad_header);
auto *Header = reinterpret_cast<const RawInstrProf::Header *>(
DataBuffer->getBufferStart());
ShouldSwapBytes = Header->Magic != RawInstrProf::getMagic<IntPtrT>();
return readHeader(*Header);
}
template <class IntPtrT>
Error RawInstrProfReader<IntPtrT>::readNextHeader(const char *CurrentPos) {
const char *End = DataBuffer->getBufferEnd();
// Skip zero padding between profiles.
while (CurrentPos != End && *CurrentPos == 0)
++CurrentPos;
// If there's nothing left, we're done.
if (CurrentPos == End)
return make_error<InstrProfError>(instrprof_error::eof);
// If there isn't enough space for another header, this is probably just
// garbage at the end of the file.
if (CurrentPos + sizeof(RawInstrProf::Header) > End)
return make_error<InstrProfError>(instrprof_error::malformed);
// The writer ensures each profile is padded to start at an aligned address.
if (reinterpret_cast<size_t>(CurrentPos) % alignof(uint64_t))
return make_error<InstrProfError>(instrprof_error::malformed);
// The magic should have the same byte order as in the previous header.
uint64_t Magic = *reinterpret_cast<const uint64_t *>(CurrentPos);
if (Magic != swap(RawInstrProf::getMagic<IntPtrT>()))
return make_error<InstrProfError>(instrprof_error::bad_magic);
// There's another profile to read, so we need to process the header.
auto *Header = reinterpret_cast<const RawInstrProf::Header *>(CurrentPos);
return readHeader(*Header);
}
template <class IntPtrT>
Error RawInstrProfReader<IntPtrT>::createSymtab(InstrProfSymtab &Symtab) {
if (Error E = Symtab.create(StringRef(NamesStart, NamesSize)))
return error(std::move(E));
for (const RawInstrProf::ProfileData<IntPtrT> *I = Data; I != DataEnd; ++I) {
const IntPtrT FPtr = swap(I->FunctionPointer);
if (!FPtr)
continue;
Symtab.mapAddress(FPtr, I->NameRef);
}
return success();
}
template <class IntPtrT>
Error RawInstrProfReader<IntPtrT>::readHeader(
const RawInstrProf::Header &Header) {
Version = swap(Header.Version);
if (GET_VERSION(Version) != RawInstrProf::Version)
return error(instrprof_error::unsupported_version);
CountersDelta = swap(Header.CountersDelta);
NamesDelta = swap(Header.NamesDelta);
auto DataSize = swap(Header.DataSize);
auto PaddingBytesBeforeCounters = swap(Header.PaddingBytesBeforeCounters);
auto CountersSize = swap(Header.CountersSize);
auto PaddingBytesAfterCounters = swap(Header.PaddingBytesAfterCounters);
NamesSize = swap(Header.NamesSize);
ValueKindLast = swap(Header.ValueKindLast);
auto DataSizeInBytes = DataSize * sizeof(RawInstrProf::ProfileData<IntPtrT>);
auto PaddingSize = getNumPaddingBytes(NamesSize);
ptrdiff_t DataOffset = sizeof(RawInstrProf::Header);
ptrdiff_t CountersOffset =
DataOffset + DataSizeInBytes + PaddingBytesBeforeCounters;
ptrdiff_t NamesOffset = CountersOffset + (sizeof(uint64_t) * CountersSize) +
PaddingBytesAfterCounters;
ptrdiff_t ValueDataOffset = NamesOffset + NamesSize + PaddingSize;
auto *Start = reinterpret_cast<const char *>(&Header);
if (Start + ValueDataOffset > DataBuffer->getBufferEnd())
return error(instrprof_error::bad_header);
Data = reinterpret_cast<const RawInstrProf::ProfileData<IntPtrT> *>(
Start + DataOffset);
DataEnd = Data + DataSize;
CountersStart = reinterpret_cast<const uint64_t *>(Start + CountersOffset);
NamesStart = Start + NamesOffset;
ValueDataStart = reinterpret_cast<const uint8_t *>(Start + ValueDataOffset);
std::unique_ptr<InstrProfSymtab> NewSymtab = std::make_unique<InstrProfSymtab>();
if (Error E = createSymtab(*NewSymtab.get()))
return E;
Symtab = std::move(NewSymtab);
return success();
}
template <class IntPtrT>
Error RawInstrProfReader<IntPtrT>::readName(NamedInstrProfRecord &Record) {
Record.Name = getName(Data->NameRef);
return success();
}
template <class IntPtrT>
Error RawInstrProfReader<IntPtrT>::readFuncHash(NamedInstrProfRecord &Record) {
Record.Hash = swap(Data->FuncHash);
return success();
}
template <class IntPtrT>
Error RawInstrProfReader<IntPtrT>::readRawCounts(
InstrProfRecord &Record) {
uint32_t NumCounters = swap(Data->NumCounters);
IntPtrT CounterPtr = Data->CounterPtr;
if (NumCounters == 0)
return error(instrprof_error::malformed);
auto *NamesStartAsCounter = reinterpret_cast<const uint64_t *>(NamesStart);
ptrdiff_t MaxNumCounters = NamesStartAsCounter - CountersStart;
// Check bounds. Note that the counter pointer embedded in the data record
// may itself be corrupt.
if (MaxNumCounters < 0 || NumCounters > (uint32_t)MaxNumCounters)
return error(instrprof_error::malformed);
ptrdiff_t CounterOffset = getCounterOffset(CounterPtr);
if (CounterOffset < 0 || CounterOffset > MaxNumCounters ||
((uint32_t)CounterOffset + NumCounters) > (uint32_t)MaxNumCounters)
return error(instrprof_error::malformed);
auto RawCounts = makeArrayRef(getCounter(CounterOffset), NumCounters);
if (ShouldSwapBytes) {
Record.Counts.clear();
Record.Counts.reserve(RawCounts.size());
for (uint64_t Count : RawCounts)
Record.Counts.push_back(swap(Count));
} else
Record.Counts = RawCounts;
return success();
}
template <class IntPtrT>
Error RawInstrProfReader<IntPtrT>::readValueProfilingData(
InstrProfRecord &Record) {
Record.clearValueData();
CurValueDataSize = 0;
// Need to match the logic in value profile dumper code in compiler-rt:
uint32_t NumValueKinds = 0;
for (uint32_t I = 0; I < IPVK_Last + 1; I++)
NumValueKinds += (Data->NumValueSites[I] != 0);
if (!NumValueKinds)
return success();
Expected<std::unique_ptr<ValueProfData>> VDataPtrOrErr =
ValueProfData::getValueProfData(
ValueDataStart, (const unsigned char *)DataBuffer->getBufferEnd(),
getDataEndianness());
if (Error E = VDataPtrOrErr.takeError())
return E;
// Note that besides deserialization, this also performs the conversion for
// indirect call targets. The function pointers from the raw profile are
// remapped into function name hashes.
VDataPtrOrErr.get()->deserializeTo(Record, Symtab.get());
CurValueDataSize = VDataPtrOrErr.get()->getSize();
return success();
}
template <class IntPtrT>
Error RawInstrProfReader<IntPtrT>::readNextRecord(NamedInstrProfRecord &Record) {
if (atEnd())
// At this point, ValueDataStart field points to the next header.
if (Error E = readNextHeader(getNextHeaderPos()))
return error(std::move(E));
// Read name ad set it in Record.
if (Error E = readName(Record))
return error(std::move(E));
// Read FuncHash and set it in Record.
if (Error E = readFuncHash(Record))
return error(std::move(E));
// Read raw counts and set Record.
if (Error E = readRawCounts(Record))
return error(std::move(E));
// Read value data and set Record.
if (Error E = readValueProfilingData(Record))
return error(std::move(E));
// Iterate.
advanceData();
return success();
}
namespace llvm {
template class RawInstrProfReader<uint32_t>;
template class RawInstrProfReader<uint64_t>;
} // end namespace llvm
InstrProfLookupTrait::hash_value_type
InstrProfLookupTrait::ComputeHash(StringRef K) {
return IndexedInstrProf::ComputeHash(HashType, K);
}
using data_type = InstrProfLookupTrait::data_type;
using offset_type = InstrProfLookupTrait::offset_type;
bool InstrProfLookupTrait::readValueProfilingData(
const unsigned char *&D, const unsigned char *const End) {
Expected<std::unique_ptr<ValueProfData>> VDataPtrOrErr =
ValueProfData::getValueProfData(D, End, ValueProfDataEndianness);
if (VDataPtrOrErr.takeError())
return false;
VDataPtrOrErr.get()->deserializeTo(DataBuffer.back(), nullptr);
D += VDataPtrOrErr.get()->TotalSize;
return true;
}
data_type InstrProfLookupTrait::ReadData(StringRef K, const unsigned char *D,
offset_type N) {
using namespace support;
// Check if the data is corrupt. If so, don't try to read it.
if (N % sizeof(uint64_t))
return data_type();
DataBuffer.clear();
std::vector<uint64_t> CounterBuffer;
const unsigned char *End = D + N;
while (D < End) {
// Read hash.
if (D + sizeof(uint64_t) >= End)
return data_type();
uint64_t Hash = endian::readNext<uint64_t, little, unaligned>(D);
// Initialize number of counters for GET_VERSION(FormatVersion) == 1.
uint64_t CountsSize = N / sizeof(uint64_t) - 1;
// If format version is different then read the number of counters.
if (GET_VERSION(FormatVersion) != IndexedInstrProf::ProfVersion::Version1) {
if (D + sizeof(uint64_t) > End)
return data_type();
CountsSize = endian::readNext<uint64_t, little, unaligned>(D);
}
// Read counter values.
if (D + CountsSize * sizeof(uint64_t) > End)
return data_type();
CounterBuffer.clear();
CounterBuffer.reserve(CountsSize);
for (uint64_t J = 0; J < CountsSize; ++J)
CounterBuffer.push_back(endian::readNext<uint64_t, little, unaligned>(D));
DataBuffer.emplace_back(K, Hash, std::move(CounterBuffer));
// Read value profiling data.
if (GET_VERSION(FormatVersion) > IndexedInstrProf::ProfVersion::Version2 &&
!readValueProfilingData(D, End)) {
DataBuffer.clear();
return data_type();
}
}
return DataBuffer;
}
template <typename HashTableImpl>
Error InstrProfReaderIndex<HashTableImpl>::getRecords(
StringRef FuncName, ArrayRef<NamedInstrProfRecord> &Data) {
auto Iter = HashTable->find(FuncName);
if (Iter == HashTable->end())
return make_error<InstrProfError>(instrprof_error::unknown_function);
Data = (*Iter);
if (Data.empty())
return make_error<InstrProfError>(instrprof_error::malformed);
return Error::success();
}
template <typename HashTableImpl>
Error InstrProfReaderIndex<HashTableImpl>::getRecords(
ArrayRef<NamedInstrProfRecord> &Data) {
if (atEnd())
return make_error<InstrProfError>(instrprof_error::eof);
Data = *RecordIterator;
if (Data.empty())
return make_error<InstrProfError>(instrprof_error::malformed);
return Error::success();
}
template <typename HashTableImpl>
InstrProfReaderIndex<HashTableImpl>::InstrProfReaderIndex(
const unsigned char *Buckets, const unsigned char *const Payload,
const unsigned char *const Base, IndexedInstrProf::HashT HashType,
uint64_t Version) {
FormatVersion = Version;
HashTable.reset(HashTableImpl::Create(
Buckets, Payload, Base,
typename HashTableImpl::InfoType(HashType, Version)));
RecordIterator = HashTable->data_begin();
}
namespace {
/// A remapper that does not apply any remappings.
class InstrProfReaderNullRemapper : public InstrProfReaderRemapper {
InstrProfReaderIndexBase &Underlying;
public:
InstrProfReaderNullRemapper(InstrProfReaderIndexBase &Underlying)
: Underlying(Underlying) {}
Error getRecords(StringRef FuncName,
ArrayRef<NamedInstrProfRecord> &Data) override {
return Underlying.getRecords(FuncName, Data);
}
};
}
/// A remapper that applies remappings based on a symbol remapping file.
template <typename HashTableImpl>
class llvm::InstrProfReaderItaniumRemapper
: public InstrProfReaderRemapper {
public:
InstrProfReaderItaniumRemapper(
std::unique_ptr<MemoryBuffer> RemapBuffer,
InstrProfReaderIndex<HashTableImpl> &Underlying)
: RemapBuffer(std::move(RemapBuffer)), Underlying(Underlying) {
}
/// Extract the original function name from a PGO function name.
static StringRef extractName(StringRef Name) {
// We can have multiple :-separated pieces; there can be pieces both
// before and after the mangled name. Find the first part that starts
// with '_Z'; we'll assume that's the mangled name we want.
std::pair<StringRef, StringRef> Parts = {StringRef(), Name};
while (true) {
Parts = Parts.second.split(':');
if (Parts.first.startswith("_Z"))
return Parts.first;
if (Parts.second.empty())
return Name;
}
}
/// Given a mangled name extracted from a PGO function name, and a new
/// form for that mangled name, reconstitute the name.
static void reconstituteName(StringRef OrigName, StringRef ExtractedName,
StringRef Replacement,
SmallVectorImpl<char> &Out) {
Out.reserve(OrigName.size() + Replacement.size() - ExtractedName.size());
Out.insert(Out.end(), OrigName.begin(), ExtractedName.begin());
Out.insert(Out.end(), Replacement.begin(), Replacement.end());
Out.insert(Out.end(), ExtractedName.end(), OrigName.end());
}
Error populateRemappings() override {
if (Error E = Remappings.read(*RemapBuffer))
return E;
for (StringRef Name : Underlying.HashTable->keys()) {
StringRef RealName = extractName(Name);
if (auto Key = Remappings.insert(RealName)) {
// FIXME: We could theoretically map the same equivalence class to
// multiple names in the profile data. If that happens, we should
// return NamedInstrProfRecords from all of them.
MappedNames.insert({Key, RealName});
}
}
return Error::success();
}
Error getRecords(StringRef FuncName,
ArrayRef<NamedInstrProfRecord> &Data) override {
StringRef RealName = extractName(FuncName);
if (auto Key = Remappings.lookup(RealName)) {
StringRef Remapped = MappedNames.lookup(Key);
if (!Remapped.empty()) {
if (RealName.begin() == FuncName.begin() &&
RealName.end() == FuncName.end())
FuncName = Remapped;
else {
// Try rebuilding the name from the given remapping.
SmallString<256> Reconstituted;
reconstituteName(FuncName, RealName, Remapped, Reconstituted);
Error E = Underlying.getRecords(Reconstituted, Data);
if (!E)
return E;
// If we failed because the name doesn't exist, fall back to asking
// about the original name.
if (Error Unhandled = handleErrors(
std::move(E), [](std::unique_ptr<InstrProfError> Err) {
return Err->get() == instrprof_error::unknown_function
? Error::success()
: Error(std::move(Err));
}))
return Unhandled;
}
}
}
return Underlying.getRecords(FuncName, Data);
}
private:
/// The memory buffer containing the remapping configuration. Remappings
/// holds pointers into this buffer.
std::unique_ptr<MemoryBuffer> RemapBuffer;
/// The mangling remapper.
SymbolRemappingReader Remappings;
/// Mapping from mangled name keys to the name used for the key in the
/// profile data.
/// FIXME: Can we store a location within the on-disk hash table instead of
/// redoing lookup?
DenseMap<SymbolRemappingReader::Key, StringRef> MappedNames;
/// The real profile data reader.
InstrProfReaderIndex<HashTableImpl> &Underlying;
};
bool IndexedInstrProfReader::hasFormat(const MemoryBuffer &DataBuffer) {
using namespace support;
if (DataBuffer.getBufferSize() < 8)
return false;
uint64_t Magic =
endian::read<uint64_t, little, aligned>(DataBuffer.getBufferStart());
// Verify that it's magical.
return Magic == IndexedInstrProf::Magic;
}
const unsigned char *
IndexedInstrProfReader::readSummary(IndexedInstrProf::ProfVersion Version,
const unsigned char *Cur, bool UseCS) {
using namespace IndexedInstrProf;
using namespace support;
if (Version >= IndexedInstrProf::Version4) {
const IndexedInstrProf::Summary *SummaryInLE =
reinterpret_cast<const IndexedInstrProf::Summary *>(Cur);
uint64_t NFields =
endian::byte_swap<uint64_t, little>(SummaryInLE->NumSummaryFields);
uint64_t NEntries =
endian::byte_swap<uint64_t, little>(SummaryInLE->NumCutoffEntries);
uint32_t SummarySize =
IndexedInstrProf::Summary::getSize(NFields, NEntries);
std::unique_ptr<IndexedInstrProf::Summary> SummaryData =
IndexedInstrProf::allocSummary(SummarySize);
const uint64_t *Src = reinterpret_cast<const uint64_t *>(SummaryInLE);
uint64_t *Dst = reinterpret_cast<uint64_t *>(SummaryData.get());
for (unsigned I = 0; I < SummarySize / sizeof(uint64_t); I++)
Dst[I] = endian::byte_swap<uint64_t, little>(Src[I]);
SummaryEntryVector DetailedSummary;
for (unsigned I = 0; I < SummaryData->NumCutoffEntries; I++) {
const IndexedInstrProf::Summary::Entry &Ent = SummaryData->getEntry(I);
DetailedSummary.emplace_back((uint32_t)Ent.Cutoff, Ent.MinBlockCount,
Ent.NumBlocks);
}
std::unique_ptr<llvm::ProfileSummary> &Summary =
UseCS ? this->CS_Summary : this->Summary;
// initialize InstrProfSummary using the SummaryData from disk.
Summary = std::make_unique<ProfileSummary>(
UseCS ? ProfileSummary::PSK_CSInstr : ProfileSummary::PSK_Instr,
DetailedSummary, SummaryData->get(Summary::TotalBlockCount),
SummaryData->get(Summary::MaxBlockCount),
SummaryData->get(Summary::MaxInternalBlockCount),
SummaryData->get(Summary::MaxFunctionCount),
SummaryData->get(Summary::TotalNumBlocks),
SummaryData->get(Summary::TotalNumFunctions));
return Cur + SummarySize;
} else {
// The older versions do not support a profile summary. This just computes
// an empty summary, which will not result in accurate hot/cold detection.
// We would need to call addRecord for all NamedInstrProfRecords to get the
// correct summary. However, this version is old (prior to early 2016) and
// has not been supporting an accurate summary for several years.
InstrProfSummaryBuilder Builder(ProfileSummaryBuilder::DefaultCutoffs);
Summary = Builder.getSummary();
return Cur;
}
}
Error IndexedInstrProfReader::readHeader() {
using namespace support;
const unsigned char *Start =
(const unsigned char *)DataBuffer->getBufferStart();
const unsigned char *Cur = Start;
if ((const unsigned char *)DataBuffer->getBufferEnd() - Cur < 24)
return error(instrprof_error::truncated);
auto *Header = reinterpret_cast<const IndexedInstrProf::Header *>(Cur);
Cur += sizeof(IndexedInstrProf::Header);
// Check the magic number.
uint64_t Magic = endian::byte_swap<uint64_t, little>(Header->Magic);
if (Magic != IndexedInstrProf::Magic)
return error(instrprof_error::bad_magic);
// Read the version.
uint64_t FormatVersion = endian::byte_swap<uint64_t, little>(Header->Version);
if (GET_VERSION(FormatVersion) >
IndexedInstrProf::ProfVersion::CurrentVersion)
return error(instrprof_error::unsupported_version);
Cur = readSummary((IndexedInstrProf::ProfVersion)FormatVersion, Cur,
/* UseCS */ false);
if (FormatVersion & VARIANT_MASK_CSIR_PROF)
Cur = readSummary((IndexedInstrProf::ProfVersion)FormatVersion, Cur,
/* UseCS */ true);
// Read the hash type and start offset.
IndexedInstrProf::HashT HashType = static_cast<IndexedInstrProf::HashT>(
endian::byte_swap<uint64_t, little>(Header->HashType));
if (HashType > IndexedInstrProf::HashT::Last)
return error(instrprof_error::unsupported_hash_type);
uint64_t HashOffset = endian::byte_swap<uint64_t, little>(Header->HashOffset);
// The rest of the file is an on disk hash table.
auto IndexPtr =
std::make_unique<InstrProfReaderIndex<OnDiskHashTableImplV3>>(
Start + HashOffset, Cur, Start, HashType, FormatVersion);
// Load the remapping table now if requested.
if (RemappingBuffer) {
Remapper = std::make_unique<
InstrProfReaderItaniumRemapper<OnDiskHashTableImplV3>>(
std::move(RemappingBuffer), *IndexPtr);
if (Error E = Remapper->populateRemappings())
return E;
} else {
Remapper = std::make_unique<InstrProfReaderNullRemapper>(*IndexPtr);
}
Index = std::move(IndexPtr);
return success();
}
InstrProfSymtab &IndexedInstrProfReader::getSymtab() {
if (Symtab.get())
return *Symtab.get();
std::unique_ptr<InstrProfSymtab> NewSymtab = std::make_unique<InstrProfSymtab>();
if (Error E = Index->populateSymtab(*NewSymtab.get())) {
consumeError(error(InstrProfError::take(std::move(E))));
}
Symtab = std::move(NewSymtab);
return *Symtab.get();
}
Expected<InstrProfRecord>
IndexedInstrProfReader::getInstrProfRecord(StringRef FuncName,
uint64_t FuncHash) {
ArrayRef<NamedInstrProfRecord> Data;
Error Err = Remapper->getRecords(FuncName, Data);
if (Err)
return std::move(Err);
// Found it. Look for counters with the right hash.
for (unsigned I = 0, E = Data.size(); I < E; ++I) {
// Check for a match and fill the vector if there is one.
if (Data[I].Hash == FuncHash) {
return std::move(Data[I]);
}
}
return error(instrprof_error::hash_mismatch);
}
Error IndexedInstrProfReader::getFunctionCounts(StringRef FuncName,
uint64_t FuncHash,
std::vector<uint64_t> &Counts) {
Expected<InstrProfRecord> Record = getInstrProfRecord(FuncName, FuncHash);
if (Error E = Record.takeError())
return error(std::move(E));
Counts = Record.get().Counts;
return success();
}
Error IndexedInstrProfReader::readNextRecord(NamedInstrProfRecord &Record) {
ArrayRef<NamedInstrProfRecord> Data;
Error E = Index->getRecords(Data);
if (E)
return error(std::move(E));
Record = Data[RecordIndex++];
if (RecordIndex >= Data.size()) {
Index->advanceToNextKey();
RecordIndex = 0;
}
return success();
}
void InstrProfReader::accumulateCounts(CountSumOrPercent &Sum, bool IsCS) {
uint64_t NumFuncs = 0;
for (const auto &Func : *this) {
if (isIRLevelProfile()) {
bool FuncIsCS = NamedInstrProfRecord::hasCSFlagInHash(Func.Hash);
if (FuncIsCS != IsCS)
continue;
}
Func.accumulateCounts(Sum);
++NumFuncs;
}
Sum.NumEntries = NumFuncs;
}