forked from OSchip/llvm-project
130 lines
4.3 KiB
C++
130 lines
4.3 KiB
C++
//===-- BenchmarkRunner.h ---------------------------------------*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
///
|
|
/// \file
|
|
/// Defines the abstract BenchmarkRunner class for measuring a certain execution
|
|
/// property of instructions (e.g. latency).
|
|
///
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_TOOLS_LLVM_EXEGESIS_BENCHMARKRUNNER_H
|
|
#define LLVM_TOOLS_LLVM_EXEGESIS_BENCHMARKRUNNER_H
|
|
|
|
#include "Assembler.h"
|
|
#include "BenchmarkResult.h"
|
|
#include "LlvmState.h"
|
|
#include "MCInstrDescView.h"
|
|
#include "RegisterAliasing.h"
|
|
#include "llvm/MC/MCInst.h"
|
|
#include "llvm/Support/Error.h"
|
|
#include <cstdlib>
|
|
#include <memory>
|
|
#include <vector>
|
|
|
|
namespace exegesis {
|
|
|
|
// A class representing failures that happened during Benchmark, they are used
|
|
// to report informations to the user.
|
|
class BenchmarkFailure : public llvm::StringError {
|
|
public:
|
|
BenchmarkFailure(const llvm::Twine &S);
|
|
};
|
|
|
|
// A collection of instructions that are to be assembled, executed and measured.
|
|
struct BenchmarkCode {
|
|
// The sequence of instructions that are to be repeated.
|
|
std::vector<llvm::MCInst> Instructions;
|
|
|
|
// Before the code is executed some instructions are added to setup the
|
|
// registers initial values.
|
|
std::vector<unsigned> RegsToDef;
|
|
|
|
// We also need to provide the registers that are live on entry for the
|
|
// assembler to generate proper prologue/epilogue.
|
|
std::vector<unsigned> LiveIns;
|
|
|
|
// Informations about how this configuration was built.
|
|
std::string Info;
|
|
};
|
|
|
|
// Common code for all benchmark modes.
|
|
class BenchmarkRunner {
|
|
public:
|
|
explicit BenchmarkRunner(const LLVMState &State,
|
|
InstructionBenchmark::ModeE Mode);
|
|
|
|
virtual ~BenchmarkRunner();
|
|
|
|
llvm::Expected<std::vector<InstructionBenchmark>>
|
|
run(unsigned Opcode, unsigned NumRepetitions);
|
|
|
|
// Given a snippet, computes which registers the setup code needs to define.
|
|
std::vector<unsigned>
|
|
computeRegsToDef(const std::vector<InstructionBuilder> &Snippet) const;
|
|
|
|
// Scratch space to run instructions that touch memory.
|
|
struct ScratchSpace {
|
|
static constexpr const size_t kAlignment = 1024;
|
|
static constexpr const size_t kSize = 1 << 20; // 1MB.
|
|
ScratchSpace()
|
|
: UnalignedPtr(llvm::make_unique<char[]>(kSize + kAlignment)),
|
|
AlignedPtr(
|
|
UnalignedPtr.get() + kAlignment -
|
|
(reinterpret_cast<intptr_t>(UnalignedPtr.get()) % kAlignment)) {}
|
|
char *ptr() const { return AlignedPtr; }
|
|
void clear() { std::memset(ptr(), 0, kSize); }
|
|
|
|
private:
|
|
const std::unique_ptr<char[]> UnalignedPtr;
|
|
char *const AlignedPtr;
|
|
};
|
|
|
|
protected:
|
|
const LLVMState &State;
|
|
const RegisterAliasingTrackerCache RATC;
|
|
|
|
// Generates a single code template that has a self-dependency.
|
|
llvm::Expected<CodeTemplate>
|
|
generateSelfAliasingCodeTemplate(const Instruction &Instr) const;
|
|
// Generates a single code template without assignment constraints.
|
|
llvm::Expected<CodeTemplate>
|
|
generateUnconstrainedCodeTemplate(const Instruction &Instr,
|
|
llvm::StringRef Msg) const;
|
|
|
|
private:
|
|
// API to be implemented by subclasses.
|
|
virtual llvm::Expected<CodeTemplate>
|
|
generateCodeTemplate(unsigned Opcode) const = 0;
|
|
|
|
virtual std::vector<BenchmarkMeasure>
|
|
runMeasurements(const ExecutableFunction &EF, ScratchSpace &Scratch,
|
|
const unsigned NumRepetitions) const = 0;
|
|
|
|
// Internal helpers.
|
|
InstructionBenchmark runConfiguration(const BenchmarkCode &Configuration,
|
|
unsigned Opcode,
|
|
unsigned NumRepetitions) const;
|
|
|
|
// Calls generateCodeTemplate and expands it into one or more BenchmarkCode.
|
|
llvm::Expected<std::vector<BenchmarkCode>>
|
|
generateConfigurations(unsigned Opcode) const;
|
|
|
|
llvm::Expected<std::string>
|
|
writeObjectFile(const BenchmarkCode &Configuration,
|
|
llvm::ArrayRef<llvm::MCInst> Code) const;
|
|
|
|
const InstructionBenchmark::ModeE Mode;
|
|
|
|
const std::unique_ptr<ScratchSpace> Scratch;
|
|
};
|
|
|
|
} // namespace exegesis
|
|
|
|
#endif // LLVM_TOOLS_LLVM_EXEGESIS_BENCHMARKRUNNER_H
|