InstructionSelect.h

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//== llvm/CodeGen/GlobalISel/InstructionSelect.h -----------------*- 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
//
//===----------------------------------------------------------------------===//
/// \file This file describes the interface of the MachineFunctionPass
/// responsible for selecting (possibly generic) machine instructions to
/// target-specific instructions.
//===----------------------------------------------------------------------===//
 
#ifndef LLVM_CODEGEN_GLOBALISEL_INSTRUCTIONSELECT_H
#define LLVM_CODEGEN_GLOBALISEL_INSTRUCTIONSELECT_H
 
#include "llvm/ADT/StringRef.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFunctionAnalysisManager.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/IR/Analysis.h"
#include "llvm/IR/PassManager.h"
#include "llvm/Support/CodeGen.h"
#include "llvm/Support/Compiler.h"
 
namespace llvm {
 
class InstructionSelector;
class GISelValueTracking;
class BlockFrequencyInfo;
class ProfileSummaryInfo;
 
/// This pass is responsible for selecting generic machine instructions to
/// target-specific instructions.  It relies on the InstructionSelector provided
/// by the target.
/// Selection is done by examining blocks in post-order, and instructions in
/// reverse order.
///
/// \post for all inst in MF: not isPreISelGenericOpcode(inst.opcode)
class LLVM_ABI InstructionSelectLegacy : public MachineFunctionPass {
public:
  static char ID;
  StringRef getPassName() const override { return "InstructionSelect"; }
 
  void getAnalysisUsage(AnalysisUsage &AU) const override;
 
  MachineFunctionProperties getRequiredProperties() const override {
    MachineFunctionProperties RequiredProperties;
    RequiredProperties.setIsSSA().setLegalized();
    if (RequireRegBankSelection)
      RequiredProperties.setRegBankSelected();
    return RequiredProperties;
  }
 
  MachineFunctionProperties getSetProperties() const override {
    return MachineFunctionProperties().setSelected();
  }
 
  InstructionSelectLegacy(CodeGenOptLevel OL = CodeGenOptLevel::Default,
                          bool RequireRegBankSelection = true,
                          char &PassID = ID);
 
  bool runOnMachineFunction(MachineFunction &MF) override;
 
protected:
  CodeGenOptLevel OptLevel = CodeGenOptLevel::None;
  bool RequireRegBankSelection = true;
};
 
class InstructionSelectImpl {
public:
  bool selectMachineFunction(MachineFunction &MF);
  void setInstructionSelector(InstructionSelector *NewISel) { ISel = NewISel; }
  bool runOnMachineFunction(MachineFunction &MF,
                            function_ref<GISelValueTracking *()> GetVT,
                            function_ref<ProfileSummaryInfo *()> GetPSI,
                            function_ref<BlockFrequencyInfo *()> GetBFI);
  InstructionSelectImpl(CodeGenOptLevel OL);
 
protected:
  class MIIteratorMaintainer;
 
  InstructionSelector *ISel = nullptr;
  GISelValueTracking *VT = nullptr;
  BlockFrequencyInfo *BFI = nullptr;
  ProfileSummaryInfo *PSI = nullptr;
 
  CodeGenOptLevel OptLevel = CodeGenOptLevel::None;
 
  bool selectInstr(MachineInstr &MI);
};
 
class InstructionSelectPass
    : public RequiredPassInfoMixin<InstructionSelectPass> {
  CodeGenOptLevel OptLevel;
  bool RequireRegBankSelection = true;
 
public:
  InstructionSelectPass(CodeGenOptLevel OL = CodeGenOptLevel::Default,
                        bool RequireRegBankSelection = true);
  PreservedAnalyses run(MachineFunction &MF,
                        MachineFunctionAnalysisManager &MFAM);
 
  MachineFunctionProperties getRequiredProperties() const {
    MachineFunctionProperties RequiredProperties;
    RequiredProperties.setIsSSA().setLegalized();
    if (RequireRegBankSelection)
      RequiredProperties.setRegBankSelected();
    return RequiredProperties;
  }
 
  MachineFunctionProperties getSetProperties() const {
    return MachineFunctionProperties().setSelected();
  }
};
 
} // End namespace llvm.
 
#endif