reference, declarationdefinition
definition → references, declarations, derived classes, virtual overrides
reference to multiple definitions → definitions
unreferenced
    1
    2
    3
    4
    5
    6
    7
    8
    9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
//===--------------------- InstrBuilder.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
///
/// A builder class for instructions that are statically analyzed by llvm-mca.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_MCA_INSTRBUILDER_H
#define LLVM_MCA_INSTRBUILDER_H

#include "llvm/MC/MCInstrAnalysis.h"
#include "llvm/MC/MCInstrInfo.h"
#include "llvm/MC/MCRegisterInfo.h"
#include "llvm/MC/MCSubtargetInfo.h"
#include "llvm/MCA/Instruction.h"
#include "llvm/MCA/Support.h"
#include "llvm/Support/Error.h"

namespace llvm {
namespace mca {

/// A builder class that knows how to construct Instruction objects.
///
/// Every llvm-mca Instruction is described by an object of class InstrDesc.
/// An InstrDesc describes which registers are read/written by the instruction,
/// as well as the instruction latency and hardware resources consumed.
///
/// This class is used by the tool to construct Instructions and instruction
/// descriptors (i.e. InstrDesc objects).
/// Information from the machine scheduling model is used to identify processor
/// resources that are consumed by an instruction.
class InstrBuilder {
  const MCSubtargetInfo &STI;
  const MCInstrInfo &MCII;
  const MCRegisterInfo &MRI;
  const MCInstrAnalysis *MCIA;
  SmallVector<uint64_t, 8> ProcResourceMasks;

  DenseMap<unsigned short, std::unique_ptr<const InstrDesc>> Descriptors;
  DenseMap<const MCInst *, std::unique_ptr<const InstrDesc>> VariantDescriptors;

  bool FirstCallInst;
  bool FirstReturnInst;

  Expected<const InstrDesc &> createInstrDescImpl(const MCInst &MCI);
  Expected<const InstrDesc &> getOrCreateInstrDesc(const MCInst &MCI);

  InstrBuilder(const InstrBuilder &) = delete;
  InstrBuilder &operator=(const InstrBuilder &) = delete;

  void populateWrites(InstrDesc &ID, const MCInst &MCI, unsigned SchedClassID);
  void populateReads(InstrDesc &ID, const MCInst &MCI, unsigned SchedClassID);
  Error verifyInstrDesc(const InstrDesc &ID, const MCInst &MCI) const;

public:
  InstrBuilder(const MCSubtargetInfo &STI, const MCInstrInfo &MCII,
               const MCRegisterInfo &RI, const MCInstrAnalysis *IA);

  void clear() {
    VariantDescriptors.shrink_and_clear();
    FirstCallInst = true;
    FirstReturnInst = true;
  }

  Expected<std::unique_ptr<Instruction>> createInstruction(const MCInst &MCI);
};
} // namespace mca
} // namespace llvm

#endif // LLVM_MCA_INSTRBUILDER_H