| //===- MacroFusion.h - Macro Fusion -----------------------------*- 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 contains the definition of the DAG scheduling mutation to |
| /// pair instructions back to back. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_CODEGEN_MACROFUSION_H |
| #define LLVM_CODEGEN_MACROFUSION_H |
| |
| #include "llvm/ADT/ArrayRef.h" |
| #include <memory> |
| |
| namespace llvm { |
| |
| class MachineInstr; |
| class ScheduleDAGMutation; |
| class TargetInstrInfo; |
| class TargetSubtargetInfo; |
| class ScheduleDAGInstrs; |
| class SUnit; |
| |
| /// 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. |
| using MacroFusionPredTy = bool (*)(const TargetInstrInfo &TII, |
| const TargetSubtargetInfo &STI, |
| const MachineInstr *FirstMI, |
| const MachineInstr &SecondMI); |
| |
| /// Checks if the number of cluster edges between SU and its predecessors is |
| /// less than FuseLimit |
| bool hasLessThanNumFused(const SUnit &SU, unsigned FuseLimit); |
| |
| /// Create an artificial edge between FirstSU and SecondSU. |
| /// Make data dependencies from the FirstSU also dependent on the SecondSU to |
| /// prevent them from being scheduled between the FirstSU and the SecondSU |
| /// and vice-versa. |
| /// Fusing more than 2 instructions is not currently supported. |
| bool fuseInstructionPair(ScheduleDAGInstrs &DAG, SUnit &FirstSU, |
| SUnit &SecondSU); |
| |
| /// Create a DAG scheduling mutation to pair instructions back to back |
| /// for instructions that benefit according to the target-specific |
| /// predicate functions. shouldScheduleAdjacent will be true if any of the |
| /// provided predicates are true. |
| /// If BranchOnly is true, only branch instructions with one of their |
| /// predecessors will be fused. |
| std::unique_ptr<ScheduleDAGMutation> |
| createMacroFusionDAGMutation(ArrayRef<MacroFusionPredTy> Predicates, |
| bool BranchOnly = false); |
| |
| } // end namespace llvm |
| |
| #endif // LLVM_CODEGEN_MACROFUSION_H |