| //=-- 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 "InstrProfIndexed.h" |
| #include "llvm/ADT/StringExtras.h" |
| #include "llvm/Support/EndianStream.h" |
| #include "llvm/Support/OnDiskHashTable.h" |
| |
| using namespace llvm; |
| |
| namespace { |
| class InstrProfRecordTrait { |
| public: |
| 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(); |
| LE.write<offset_type>(N); |
| |
| offset_type M = 0; |
| for (const auto &Counts : *V) |
| M += (2 + Counts.second.size()) * sizeof(uint64_t); |
| 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 &Counts : *V) { |
| LE.write<uint64_t>(Counts.first); |
| LE.write<uint64_t>(Counts.second.size()); |
| for (uint64_t I : Counts.second) |
| LE.write<uint64_t>(I); |
| } |
| } |
| }; |
| } |
| |
| std::error_code |
| InstrProfWriter::addFunctionCounts(StringRef FunctionName, |
| uint64_t FunctionHash, |
| ArrayRef<uint64_t> Counters) { |
| auto &CounterData = FunctionData[FunctionName]; |
| |
| auto Where = CounterData.find(FunctionHash); |
| if (Where == CounterData.end()) { |
| // We've never seen a function with this name and hash, add it. |
| CounterData[FunctionHash] = Counters; |
| // We keep track of the max function count as we go for simplicity. |
| if (Counters[0] > MaxFunctionCount) |
| MaxFunctionCount = Counters[0]; |
| return instrprof_error::success; |
| } |
| |
| // We're updating a function we've seen before. |
| auto &FoundCounters = Where->second; |
| // If the number of counters doesn't match we either have bad data or a hash |
| // collision. |
| if (FoundCounters.size() != Counters.size()) |
| return instrprof_error::count_mismatch; |
| |
| for (size_t I = 0, E = Counters.size(); I < E; ++I) { |
| if (FoundCounters[I] + Counters[I] < FoundCounters[I]) |
| return instrprof_error::counter_overflow; |
| FoundCounters[I] += Counters[I]; |
| } |
| // We keep track of the max function count as we go for simplicity. |
| if (FoundCounters[0] > MaxFunctionCount) |
| MaxFunctionCount = FoundCounters[0]; |
| |
| return instrprof_error::success; |
| } |
| |
| void InstrProfWriter::write(raw_fd_ostream &OS) { |
| OnDiskChainedHashTableGenerator<InstrProfRecordTrait> Generator; |
| |
| // Populate the hash table generator. |
| for (const auto &I : FunctionData) |
| Generator.insert(I.getKey(), &I.getValue()); |
| |
| using namespace llvm::support; |
| endian::Writer<little> LE(OS); |
| |
| // Write the header. |
| LE.write<uint64_t>(IndexedInstrProf::Magic); |
| LE.write<uint64_t>(IndexedInstrProf::Version); |
| LE.write<uint64_t>(MaxFunctionCount); |
| LE.write<uint64_t>(static_cast<uint64_t>(IndexedInstrProf::HashType)); |
| |
| // Save a space to write the hash table start location. |
| uint64_t HashTableStartLoc = OS.tell(); |
| LE.write<uint64_t>(0); |
| // Write the hash table. |
| uint64_t HashTableStart = Generator.Emit(OS); |
| |
| // Go back and fill in the hash table start. |
| OS.seek(HashTableStartLoc); |
| LE.write<uint64_t>(HashTableStart); |
| } |