llvm/llvm/lib/Target/AArch64/AArch64MacroFusion.cpp

//===- AArch64MacroFusion.cpp - AArch64 Macro Fusion ----------------------===//
//
// 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 contains the AArch64 implementation of the DAG scheduling
///  mutation to pair instructions back to back.
//
//===----------------------------------------------------------------------===//

#include "AArch64MacroFusion.h"
#include "AArch64Subtarget.h"
#include "llvm/CodeGen/MacroFusion.h"
#include "llvm/CodeGen/TargetInstrInfo.h"

usingnamespacellvm;

/// CMN, CMP, TST followed by Bcc
static bool isArithmeticBccPair(const MachineInstr *FirstMI,
                                const MachineInstr &SecondMI, bool CmpOnly) { … }

/// ALU operations followed by CBZ/CBNZ.
static bool isArithmeticCbzPair(const MachineInstr *FirstMI,
                                const MachineInstr &SecondMI) { … }

/// AES crypto encoding or decoding.
static bool isAESPair(const MachineInstr *FirstMI,
                      const MachineInstr &SecondMI) { … }

/// AESE/AESD/PMULL + EOR.
static bool isCryptoEORPair(const MachineInstr *FirstMI,
                            const MachineInstr &SecondMI) { … }

static bool isAdrpAddPair(const MachineInstr *FirstMI,
                          const MachineInstr &SecondMI) { … }

/// Literal generation.
static bool isLiteralsPair(const MachineInstr *FirstMI,
                           const MachineInstr &SecondMI) { … }

/// Fuse address generation and loads or stores.
static bool isAddressLdStPair(const MachineInstr *FirstMI,
                              const MachineInstr &SecondMI) { … }

/// Compare and conditional select.
static bool isCCSelectPair(const MachineInstr *FirstMI,
                           const MachineInstr &SecondMI) { … }

// Arithmetic and logic.
static bool isArithmeticLogicPair(const MachineInstr *FirstMI,
                                  const MachineInstr &SecondMI) { … }

// "(A + B) + 1" or "(A - B) - 1"
static bool isAddSub2RegAndConstOnePair(const MachineInstr *FirstMI,
                                        const MachineInstr &SecondMI) { … }

/// \brief Check if the instr pair, FirstMI and SecondMI, should be fused
/// together. Given SecondMI, when FirstMI is unspecified, then check if
/// SecondMI may be part of a fused pair at all.
static bool shouldScheduleAdjacent(const TargetInstrInfo &TII,
                                   const TargetSubtargetInfo &TSI,
                                   const MachineInstr *FirstMI,
                                   const MachineInstr &SecondMI) { … }

std::unique_ptr<ScheduleDAGMutation>
llvm::createAArch64MacroFusionDAGMutation() { … }