include/llvm/MCA/Stages/EntryStage.h

   1 //===---------------------- EntryStage.h ------------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 /// \file
   9 ///
  10 /// This file defines the Entry stage of an instruction pipeline.  Its sole
  11 /// purpose in life is to pick instructions in sequence and move them to the
  12 /// next pipeline stage.
  13 ///
  14 //===----------------------------------------------------------------------===//
  15
  16 #ifndef LLVM_MCA_ENTRY_STAGE_H
  17 #define LLVM_MCA_ENTRY_STAGE_H
  18
  19 #include "llvm/ADT/SmallVector.h"
  20 #include "llvm/MCA/SourceMgr.h"
  21 #include "llvm/MCA/Stages/Stage.h"
  22
  23 namespace llvm {
  24 namespace mca {
  25
  26 class EntryStage final : public Stage {
  27   InstRef CurrentInstruction;
  28   SmallVector<std::unique_ptr<Instruction>, 16> Instructions;
  29   SourceMgr &SM;
  30   unsigned NumRetired;
  31
  32   // Updates the program counter, and sets 'CurrentInstruction'.
  33   void getNextInstruction();
  34
  35   EntryStage(const EntryStage &Other) = delete;
  36   EntryStage &operator=(const EntryStage &Other) = delete;
  37
  38 public:
  39   EntryStage(SourceMgr &SM) : CurrentInstruction(), SM(SM), NumRetired(0) { }
  40
  41   bool isAvailable(const InstRef &IR) const override;
  42   bool hasWorkToComplete() const override;
  43   Error execute(InstRef &IR) override;
  44   Error cycleStart() override;
  45   Error cycleEnd() override;
  46 };
  47
  48 } // namespace mca
  49 } // namespace llvm
  50
  51 #endif // LLVM_MCA_FETCH_STAGE_H