include/llvm/ProfileData/InstrProfWriter.h - llvm-project/llvm - Git at Google

 //===- InstrProfWriter.h - Instrumented profiling writer --------*- C++ -*-===//
 //
 // 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 writing profiling data for instrumentation
 // based PGO and coverage.
 //
 //===----------------------------------------------------------------------===//

 #ifndef LLVM_PROFILEDATA_INSTRPROFWRITER_H
 #define LLVM_PROFILEDATA_INSTRPROFWRITER_H

 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/MapVector.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/IR/GlobalValue.h"
 #include "llvm/Object/BuildID.h"
 #include "llvm/ProfileData/InstrProf.h"
 #include "llvm/ProfileData/MemProf.h"
 #include "llvm/Support/Error.h"
 #include <cstdint>
 #include <memory>
 #include <random>

 namespace llvm {

 /// Writer for instrumentation based profile data.
 class InstrProfRecordWriterTrait;
 class ProfOStream;
 class MemoryBuffer;
 class raw_fd_ostream;

 class InstrProfWriter {
 public:
   using ProfilingData = SmallDenseMap<uint64_t, InstrProfRecord>;

 private:
   bool Sparse;
   StringMap<ProfilingData> FunctionData;
   /// The maximum length of a single temporal profile trace.
   uint64_t MaxTemporalProfTraceLength;
   /// The maximum number of stored temporal profile traces.
   uint64_t TemporalProfTraceReservoirSize;
   /// The total number of temporal profile traces seen.
   uint64_t TemporalProfTraceStreamSize = 0;
   /// The list of temporal profile traces.
   SmallVector<TemporalProfTraceTy> TemporalProfTraces;
   std::mt19937 RNG;

   // The MemProf data.
   memprof::IndexedMemProfData MemProfData;

   // List of binary ids.
   std::vector<llvm::object::BuildID> BinaryIds;

   // Read the vtable names from raw instr profile reader.
   StringSet<> VTableNames;

   // An enum describing the attributes of the profile.
   InstrProfKind ProfileKind = InstrProfKind::Unknown;
   // Use raw pointer here for the incomplete type object.
   InstrProfRecordWriterTrait *InfoObj;

   // Temporary support for writing the previous version of the format, to enable
   // some forward compatibility. Currently this suppresses the writing of the
   // new vtable names section and header fields.
   // TODO: Consider enabling this with future version changes as well, to ease
   // deployment of newer versions of llvm-profdata.
   bool WritePrevVersion = false;

   // The MemProf version we should write.
   memprof::IndexedVersion MemProfVersionRequested;

   // Whether to serialize the full schema.
   bool MemProfFullSchema;

 public:
   InstrProfWriter(
       bool Sparse = false, uint64_t TemporalProfTraceReservoirSize = 0,
       uint64_t MaxTemporalProfTraceLength = 0, bool WritePrevVersion = false,
       memprof::IndexedVersion MemProfVersionRequested = memprof::Version0,
       bool MemProfFullSchema = false);
   ~InstrProfWriter();

   StringMap<ProfilingData> &getProfileData() { return FunctionData; }

   /// Add function counts for the given function. If there are already counts
   /// for this function and the hash and number of counts match, each counter is
   /// summed. Optionally scale counts by \p Weight.
   void addRecord(NamedInstrProfRecord &&I, uint64_t Weight,
                  function_ref<void(Error)> Warn);
   void addRecord(NamedInstrProfRecord &&I, function_ref<void(Error)> Warn) {
     addRecord(std::move(I), 1, Warn);
   }
   void addVTableName(StringRef VTableName) { VTableNames.insert(VTableName); }

   /// Add \p SrcTraces using reservoir sampling where \p SrcStreamSize is the
   /// total number of temporal profiling traces the source has seen.
   void addTemporalProfileTraces(SmallVectorImpl<TemporalProfTraceTy> &SrcTraces,
                                 uint64_t SrcStreamSize);

   /// Add a memprof record for a function identified by its \p Id.
   void addMemProfRecord(const GlobalValue::GUID Id,
                         const memprof::IndexedMemProfRecord &Record);

   /// Add a memprof frame identified by the hash of the contents of the frame in
   /// \p FrameId.
   bool addMemProfFrame(const memprof::FrameId, const memprof::Frame &F,
                        function_ref<void(Error)> Warn);

   /// Add a call stack identified by the hash of the contents of the call stack
   /// in \p CallStack.
   bool addMemProfCallStack(const memprof::CallStackId CSId,
                            const llvm::SmallVector<memprof::FrameId> &CallStack,
                            function_ref<void(Error)> Warn);

   // Add a binary id to the binary ids list.
   void addBinaryIds(ArrayRef<llvm::object::BuildID> BIs);

   /// Merge existing function counts from the given writer.
   void mergeRecordsFromWriter(InstrProfWriter &&IPW,
                               function_ref<void(Error)> Warn);

   /// Write the profile to \c OS
   Error write(raw_fd_ostream &OS);

   /// Write the profile to a string output stream \c OS
   Error write(raw_string_ostream &OS);

   /// Write the profile in text format to \c OS
   Error writeText(raw_fd_ostream &OS);

   /// Write temporal profile trace data to the header in text format to \c OS
   void writeTextTemporalProfTraceData(raw_fd_ostream &OS,
                                       InstrProfSymtab &Symtab);

   Error validateRecord(const InstrProfRecord &Func);

   /// Write \c Record in text format to \c OS
   static void writeRecordInText(StringRef Name, uint64_t Hash,
                                 const InstrProfRecord &Counters,
                                 InstrProfSymtab &Symtab, raw_fd_ostream &OS);

   /// Write the profile, returning the raw data. For testing.
   std::unique_ptr<MemoryBuffer> writeBuffer();

   /// Update the attributes of the current profile from the attributes
   /// specified. An error is returned if IR and FE profiles are mixed.
   Error mergeProfileKind(const InstrProfKind Other) {
     // If the kind is unset, this is the first profile we are merging so just
     // set it to the given type.
     if (ProfileKind == InstrProfKind::Unknown) {
       ProfileKind = Other;
       return Error::success();
     }

     // Returns true if merging is should fail assuming A and B are incompatible.
     auto testIncompatible = [&](InstrProfKind A, InstrProfKind B) {
       return (static_cast<bool>(ProfileKind & A) &&
               static_cast<bool>(Other & B)) ||
              (static_cast<bool>(ProfileKind & B) &&
               static_cast<bool>(Other & A));
     };

     // Check if the profiles are in-compatible. Clang frontend profiles can't be
     // merged with other profile types.
     if (static_cast<bool>(
             (ProfileKind & InstrProfKind::FrontendInstrumentation) ^
             (Other & InstrProfKind::FrontendInstrumentation))) {
       return make_error<InstrProfError>(instrprof_error::unsupported_version);
     }
     if (testIncompatible(InstrProfKind::FunctionEntryOnly,
                          InstrProfKind::FunctionEntryInstrumentation)) {
       return make_error<InstrProfError>(
           instrprof_error::unsupported_version,
           "cannot merge FunctionEntryOnly profiles and BB profiles together");
     }

     // Now we update the profile type with the bits that are set.
     ProfileKind |= Other;
     return Error::success();
   }

   InstrProfKind getProfileKind() const { return ProfileKind; }

   bool hasSingleByteCoverage() const {
     return static_cast<bool>(ProfileKind & InstrProfKind::SingleByteCoverage);
   }

   // Internal interfaces for testing purpose only.
   void setValueProfDataEndianness(llvm::endianness Endianness);
   void setOutputSparse(bool Sparse);
   void setMemProfVersionRequested(memprof::IndexedVersion Version) {
     MemProfVersionRequested = Version;
   }
   void setMemProfFullSchema(bool Full) { MemProfFullSchema = Full; }
   // Compute the overlap b/w this object and Other. Program level result is
   // stored in Overlap and function level result is stored in FuncLevelOverlap.
   void overlapRecord(NamedInstrProfRecord &&Other, OverlapStats &Overlap,
                      OverlapStats &FuncLevelOverlap,
                      const OverlapFuncFilters &FuncFilter);

 private:
   void addRecord(StringRef Name, uint64_t Hash, InstrProfRecord &&I,
                  uint64_t Weight, function_ref<void(Error)> Warn);
   bool shouldEncodeData(const ProfilingData &PD);
   /// Add \p Trace using reservoir sampling.
   void addTemporalProfileTrace(TemporalProfTraceTy Trace);

   Error writeImpl(ProfOStream &OS);

   // Writes known header fields and reserves space for fields whose value are
   // known only after payloads are written. Returns the start byte offset for
   // back patching.
   uint64_t writeHeader(const IndexedInstrProf::Header &header,
                        const bool WritePrevVersion, ProfOStream &OS);

   // Writes compressed vtable names to profiles.
   Error writeVTableNames(ProfOStream &OS);
 };

 } // end namespace llvm

 #endif // LLVM_PROFILEDATA_INSTRPROFWRITER_H
	//===- InstrProfWriter.h - Instrumented profiling writer --------- C++ --===//
	//
	// 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 writing profiling data for instrumentation
	// based PGO and coverage.
	//
	//===----------------------------------------------------------------------===//

	#ifndef LLVM_PROFILEDATA_INSTRPROFWRITER_H
	#define LLVM_PROFILEDATA_INSTRPROFWRITER_H

	#include "llvm/ADT/DenseMap.h"
	#include "llvm/ADT/MapVector.h"
	#include "llvm/ADT/StringMap.h"
	#include "llvm/IR/GlobalValue.h"
	#include "llvm/Object/BuildID.h"
	#include "llvm/ProfileData/InstrProf.h"
	#include "llvm/ProfileData/MemProf.h"
	#include "llvm/Support/Error.h"
	#include <cstdint>
	#include <memory>
	#include <random>

	namespace llvm {

	/// Writer for instrumentation based profile data.
	class InstrProfRecordWriterTrait;
	class ProfOStream;
	class MemoryBuffer;
	class raw_fd_ostream;

	class InstrProfWriter {
	public:
	using ProfilingData = SmallDenseMap<uint64_t, InstrProfRecord>;

	private:
	bool Sparse;
	StringMap<ProfilingData> FunctionData;
	/// The maximum length of a single temporal profile trace.
	uint64_t MaxTemporalProfTraceLength;
	/// The maximum number of stored temporal profile traces.
	uint64_t TemporalProfTraceReservoirSize;
	/// The total number of temporal profile traces seen.
	uint64_t TemporalProfTraceStreamSize = 0;
	/// The list of temporal profile traces.
	SmallVector<TemporalProfTraceTy> TemporalProfTraces;
	std::mt19937 RNG;

	// The MemProf data.
	memprof::IndexedMemProfData MemProfData;

	// List of binary ids.
	std::vector<llvm::object::BuildID> BinaryIds;

	// Read the vtable names from raw instr profile reader.
	StringSet<> VTableNames;

	// An enum describing the attributes of the profile.
	InstrProfKind ProfileKind = InstrProfKind::Unknown;
	// Use raw pointer here for the incomplete type object.
	InstrProfRecordWriterTrait *InfoObj;

	// Temporary support for writing the previous version of the format, to enable
	// some forward compatibility. Currently this suppresses the writing of the
	// new vtable names section and header fields.
	// TODO: Consider enabling this with future version changes as well, to ease
	// deployment of newer versions of llvm-profdata.
	bool WritePrevVersion = false;

	// The MemProf version we should write.
	memprof::IndexedVersion MemProfVersionRequested;

	// Whether to serialize the full schema.
	bool MemProfFullSchema;

	public:
	InstrProfWriter(
	bool Sparse = false, uint64_t TemporalProfTraceReservoirSize = 0,
	uint64_t MaxTemporalProfTraceLength = 0, bool WritePrevVersion = false,
	memprof::IndexedVersion MemProfVersionRequested = memprof::Version0,
	bool MemProfFullSchema = false);
	~InstrProfWriter();

	StringMap<ProfilingData> &getProfileData() { return FunctionData; }

	/// Add function counts for the given function. If there are already counts
	/// for this function and the hash and number of counts match, each counter is
	/// summed. Optionally scale counts by \p Weight.
	void addRecord(NamedInstrProfRecord &&I, uint64_t Weight,
	function_ref<void(Error)> Warn);
	void addRecord(NamedInstrProfRecord &&I, function_ref<void(Error)> Warn) {
	addRecord(std::move(I), 1, Warn);
	}
	void addVTableName(StringRef VTableName) { VTableNames.insert(VTableName); }

	/// Add \p SrcTraces using reservoir sampling where \p SrcStreamSize is the
	/// total number of temporal profiling traces the source has seen.
	void addTemporalProfileTraces(SmallVectorImpl<TemporalProfTraceTy> &SrcTraces,
	uint64_t SrcStreamSize);

	/// Add a memprof record for a function identified by its \p Id.
	void addMemProfRecord(const GlobalValue::GUID Id,
	const memprof::IndexedMemProfRecord &Record);

	/// Add a memprof frame identified by the hash of the contents of the frame in
	/// \p FrameId.
	bool addMemProfFrame(const memprof::FrameId, const memprof::Frame &F,
	function_ref<void(Error)> Warn);

	/// Add a call stack identified by the hash of the contents of the call stack
	/// in \p CallStack.
	bool addMemProfCallStack(const memprof::CallStackId CSId,
	const llvm::SmallVector<memprof::FrameId> &CallStack,
	function_ref<void(Error)> Warn);

	// Add a binary id to the binary ids list.
	void addBinaryIds(ArrayRef<llvm::object::BuildID> BIs);

	/// Merge existing function counts from the given writer.
	void mergeRecordsFromWriter(InstrProfWriter &&IPW,
	function_ref<void(Error)> Warn);

	/// Write the profile to \c OS
	Error write(raw_fd_ostream &OS);

	/// Write the profile to a string output stream \c OS
	Error write(raw_string_ostream &OS);

	/// Write the profile in text format to \c OS
	Error writeText(raw_fd_ostream &OS);

	/// Write temporal profile trace data to the header in text format to \c OS
	void writeTextTemporalProfTraceData(raw_fd_ostream &OS,
	InstrProfSymtab &Symtab);

	Error validateRecord(const InstrProfRecord &Func);

	/// Write \c Record in text format to \c OS
	static void writeRecordInText(StringRef Name, uint64_t Hash,
	const InstrProfRecord &Counters,
	InstrProfSymtab &Symtab, raw_fd_ostream &OS);

	/// Write the profile, returning the raw data. For testing.
	std::unique_ptr<MemoryBuffer> writeBuffer();

	/// Update the attributes of the current profile from the attributes
	/// specified. An error is returned if IR and FE profiles are mixed.
	Error mergeProfileKind(const InstrProfKind Other) {
	// If the kind is unset, this is the first profile we are merging so just
	// set it to the given type.
	if (ProfileKind == InstrProfKind::Unknown) {
	ProfileKind = Other;
	return Error::success();
	}

	// Returns true if merging is should fail assuming A and B are incompatible.
	auto testIncompatible = [&](InstrProfKind A, InstrProfKind B) {
	return (static_cast<bool>(ProfileKind & A) &&
	static_cast<bool>(Other & B)) \|\|
	(static_cast<bool>(ProfileKind & B) &&
	static_cast<bool>(Other & A));
	};

	// Check if the profiles are in-compatible. Clang frontend profiles can't be
	// merged with other profile types.
	if (static_cast<bool>(
	(ProfileKind & InstrProfKind::FrontendInstrumentation) ^
	(Other & InstrProfKind::FrontendInstrumentation))) {
	return make_error<InstrProfError>(instrprof_error::unsupported_version);
	}
	if (testIncompatible(InstrProfKind::FunctionEntryOnly,
	InstrProfKind::FunctionEntryInstrumentation)) {
	return make_error<InstrProfError>(
	instrprof_error::unsupported_version,
	"cannot merge FunctionEntryOnly profiles and BB profiles together");
	}

	// Now we update the profile type with the bits that are set.
	ProfileKind \|= Other;
	return Error::success();
	}

	InstrProfKind getProfileKind() const { return ProfileKind; }

	bool hasSingleByteCoverage() const {
	return static_cast<bool>(ProfileKind & InstrProfKind::SingleByteCoverage);
	}

	// Internal interfaces for testing purpose only.
	void setValueProfDataEndianness(llvm::endianness Endianness);
	void setOutputSparse(bool Sparse);
	void setMemProfVersionRequested(memprof::IndexedVersion Version) {
	MemProfVersionRequested = Version;
	}
	void setMemProfFullSchema(bool Full) { MemProfFullSchema = Full; }
	// Compute the overlap b/w this object and Other. Program level result is
	// stored in Overlap and function level result is stored in FuncLevelOverlap.
	void overlapRecord(NamedInstrProfRecord &&Other, OverlapStats &Overlap,
	OverlapStats &FuncLevelOverlap,
	const OverlapFuncFilters &FuncFilter);

	private:
	void addRecord(StringRef Name, uint64_t Hash, InstrProfRecord &&I,
	uint64_t Weight, function_ref<void(Error)> Warn);
	bool shouldEncodeData(const ProfilingData &PD);
	/// Add \p Trace using reservoir sampling.
	void addTemporalProfileTrace(TemporalProfTraceTy Trace);

	Error writeImpl(ProfOStream &OS);

	// Writes known header fields and reserves space for fields whose value are
	// known only after payloads are written. Returns the start byte offset for
	// back patching.
	uint64_t writeHeader(const IndexedInstrProf::Header &header,
	const bool WritePrevVersion, ProfOStream &OS);

	// Writes compressed vtable names to profiles.
	Error writeVTableNames(ProfOStream &OS);
	};

	} // end namespace llvm

	#endif // LLVM_PROFILEDATA_INSTRPROFWRITER_H