tools/llvm-exegesis/lib/Target.h

   1 //===-- Target.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 ///
  12 /// Classes that handle the creation of target-specific objects. This is
  13 /// similar to llvm::Target/TargetRegistry.
  14 ///
  15 //===----------------------------------------------------------------------===//
  16
  17 #ifndef LLVM_TOOLS_LLVM_EXEGESIS_TARGET_H
  18 #define LLVM_TOOLS_LLVM_EXEGESIS_TARGET_H
  19
  20 #include "BenchmarkResult.h"
  21 #include "BenchmarkRunner.h"
  22 #include "LlvmState.h"
  23 #include "SnippetGenerator.h"
  24 #include "llvm/ADT/Triple.h"
  25 #include "llvm/CodeGen/TargetPassConfig.h"
  26 #include "llvm/IR/CallingConv.h"
  27 #include "llvm/IR/LegacyPassManager.h"
  28 #include "llvm/MC/MCInst.h"
  29 #include "llvm/MC/MCRegisterInfo.h"
  30
  31 namespace exegesis {
  32
  33 class ExegesisTarget {
  34 public:
  35   // Targets can use this to add target-specific passes in assembleToStream();
  36   virtual void addTargetSpecificPasses(llvm::PassManagerBase &PM) const {}
  37
  38   // Generates code to move a constant into a the given register.
  39   virtual std::vector<llvm::MCInst> setRegTo(const llvm::MCSubtargetInfo &STI,
  40                                              const llvm::APInt &Value,
  41                                              unsigned Reg) const = 0;
  42
  43   // Returns the register pointing to scratch memory, or 0 if this target
  44   // does not support memory operands. The benchmark function uses the
  45   // default calling convention.
  46   virtual unsigned getScratchMemoryRegister(const llvm::Triple &) const = 0;
  47
  48   // Fills memory operands with references to the address at [Reg] + Offset.
  49   virtual void fillMemoryOperands(InstructionBuilder &IB, unsigned Reg,
  50                                   unsigned Offset) const = 0;
  51
  52   // Returns the maximum number of bytes a load/store instruction can access at
  53   // once. This is typically the size of the largest register available on the
  54   // processor. Note that this only used as a hint to generate independant
  55   // load/stores to/from memory, so the exact returned value does not really
  56   // matter as long as it's large enough.
  57   virtual unsigned getMaxMemoryAccessSize() const = 0;
  58
  59   // Creates a snippet generator for the given mode.
  60   std::unique_ptr<SnippetGenerator>
  61   createSnippetGenerator(InstructionBenchmark::ModeE Mode,
  62                          const LLVMState &State) const;
  63   // Creates a benchmark runner for the given mode.
  64   std::unique_ptr<BenchmarkRunner>
  65   createBenchmarkRunner(InstructionBenchmark::ModeE Mode,
  66                         const LLVMState &State) const;
  67
  68   // Returns the ExegesisTarget for the given triple or nullptr if the target
  69   // does not exist.
  70   static const ExegesisTarget *lookup(llvm::Triple TT);
  71   // Returns the default (unspecialized) ExegesisTarget.
  72   static const ExegesisTarget &getDefault();
  73   // Registers a target. Not thread safe.
  74   static void registerTarget(ExegesisTarget *T);
  75
  76   virtual ~ExegesisTarget();
  77
  78 private:
  79   virtual bool matchesArch(llvm::Triple::ArchType Arch) const = 0;
  80
  81   // Targets can implement their own snippet generators/benchmarks runners by
  82   // implementing these.
  83   std::unique_ptr<SnippetGenerator> virtual createLatencySnippetGenerator(
  84       const LLVMState &State) const;
  85   std::unique_ptr<SnippetGenerator> virtual createUopsSnippetGenerator(
  86       const LLVMState &State) const;
  87   std::unique_ptr<BenchmarkRunner> virtual createLatencyBenchmarkRunner(
  88       const LLVMState &State) const;
  89   std::unique_ptr<BenchmarkRunner> virtual createUopsBenchmarkRunner(
  90       const LLVMState &State) const;
  91
  92   const ExegesisTarget *Next = nullptr;
  93 };
  94
  95 } // namespace exegesis
  96
  97 #endif // LLVM_TOOLS_LLVM_EXEGESIS_TARGET_H