tools/llvm-exegesis/lib/Latency.h

   1 //===-- Latency.h -----------------------------------------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 ///
  10 /// \file
  11 /// A BenchmarkRunner implementation to measure instruction latencies.
  12 ///
  13 //===----------------------------------------------------------------------===//
  14
  15 #ifndef LLVM_TOOLS_LLVM_EXEGESIS_LATENCY_H
  16 #define LLVM_TOOLS_LLVM_EXEGESIS_LATENCY_H
  17
  18 #include "BenchmarkRunner.h"
  19 #include "MCInstrDescView.h"
  20 #include "SnippetGenerator.h"
  21
  22 namespace exegesis {
  23
  24 class LatencySnippetGenerator : public SnippetGenerator {
  25 public:
  26   LatencySnippetGenerator(const LLVMState &State) : SnippetGenerator(State) {}
  27   ~LatencySnippetGenerator() override;
  28
  29   llvm::Expected<CodeTemplate>
  30   generateCodeTemplate(unsigned Opcode) const override;
  31
  32 private:
  33   llvm::Error isInfeasible(const llvm::MCInstrDesc &MCInstrDesc) const;
  34
  35   llvm::Expected<CodeTemplate>
  36   generateTwoInstructionPrototype(const Instruction &Instr) const;
  37 };
  38
  39 class LatencyBenchmarkRunner : public BenchmarkRunner {
  40 public:
  41   LatencyBenchmarkRunner(const LLVMState &State)
  42       : BenchmarkRunner(State, InstructionBenchmark::Latency) {}
  43   ~LatencyBenchmarkRunner() override;
  44
  45 private:
  46   std::vector<BenchmarkMeasure>
  47   runMeasurements(const ExecutableFunction &EF,
  48                   ScratchSpace &Scratch) const override;
  49
  50   virtual const char *getCounterName() const;
  51 };
  52 } // namespace exegesis
  53
  54 #endif // LLVM_TOOLS_LLVM_EXEGESIS_LATENCY_H