llvm/llvm/lib/Target/PowerPC/PPCMacroFusion.cpp

//===- PPCMacroFusion.cpp - PowerPC 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 PowerPC implementation of the DAG scheduling
///  mutation to pair instructions back to back.
//
//===----------------------------------------------------------------------===//

#include "PPC.h"
#include "PPCSubtarget.h"
#include "llvm/ADT/DenseSet.h"
#include "llvm/CodeGen/MacroFusion.h"
#include "llvm/CodeGen/ScheduleDAGMutation.h"
#include <optional>

usingnamespacellvm;
namespace {

class FusionFeature { … };

static bool matchingRegOps(const MachineInstr &FirstMI,
                           int FirstMIOpIndex,
                           const MachineInstr &SecondMI,
                           int SecondMIOpIndex) { … }

static bool matchingImmOps(const MachineInstr &MI,
                           int MIOpIndex,
                           int64_t Expect,
                           unsigned ExtendFrom = 64) { … }

// Return true if the FirstMI meets the constraints of SecondMI according to
// fusion specification.
static bool checkOpConstraints(FusionFeature::FusionKind Kd,
                               const MachineInstr &FirstMI,
                               const MachineInstr &SecondMI) { … }

/// 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) { … }

} // end anonymous namespace

namespace llvm {

std::unique_ptr<ScheduleDAGMutation> createPowerPCMacroFusionDAGMutation() { … }

} // end namespace llvm