llvm-capstone/llvm/lib/MCA/Context.cpp
Andrew Savonichev bcc83a2e83 [MCA] Use LSU for the in-order pipeline
Load/Store unit is used to enforce order of loads and stores if they
alias (controlled by --noalias=false option).

Fixes PR50483 - [MCA] In-order pipeline doesn't track memory
load/store dependencies.

Differential Revision: https://reviews.llvm.org/D103955
2021-07-29 14:40:23 +03:00

97 lines
3.8 KiB
C++

//===---------------------------- Context.cpp -------------------*- 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 defines a class for holding ownership of various simulated
/// hardware units. A Context also provides a utility routine for constructing
/// a default out-of-order pipeline with fetch, dispatch, execute, and retire
/// stages.
///
//===----------------------------------------------------------------------===//
#include "llvm/MCA/Context.h"
#include "llvm/MCA/HardwareUnits/RegisterFile.h"
#include "llvm/MCA/HardwareUnits/RetireControlUnit.h"
#include "llvm/MCA/HardwareUnits/Scheduler.h"
#include "llvm/MCA/Stages/DispatchStage.h"
#include "llvm/MCA/Stages/EntryStage.h"
#include "llvm/MCA/Stages/ExecuteStage.h"
#include "llvm/MCA/Stages/InOrderIssueStage.h"
#include "llvm/MCA/Stages/MicroOpQueueStage.h"
#include "llvm/MCA/Stages/RetireStage.h"
namespace llvm {
namespace mca {
std::unique_ptr<Pipeline>
Context::createDefaultPipeline(const PipelineOptions &Opts, SourceMgr &SrcMgr,
CustomBehaviour &CB) {
const MCSchedModel &SM = STI.getSchedModel();
if (!SM.isOutOfOrder())
return createInOrderPipeline(Opts, SrcMgr, CB);
// Create the hardware units defining the backend.
auto RCU = std::make_unique<RetireControlUnit>(SM);
auto PRF = std::make_unique<RegisterFile>(SM, MRI, Opts.RegisterFileSize);
auto LSU = std::make_unique<LSUnit>(SM, Opts.LoadQueueSize,
Opts.StoreQueueSize, Opts.AssumeNoAlias);
auto HWS = std::make_unique<Scheduler>(SM, *LSU);
// Create the pipeline stages.
auto Fetch = std::make_unique<EntryStage>(SrcMgr);
auto Dispatch =
std::make_unique<DispatchStage>(STI, MRI, Opts.DispatchWidth, *RCU, *PRF);
auto Execute =
std::make_unique<ExecuteStage>(*HWS, Opts.EnableBottleneckAnalysis);
auto Retire = std::make_unique<RetireStage>(*RCU, *PRF, *LSU);
// Pass the ownership of all the hardware units to this Context.
addHardwareUnit(std::move(RCU));
addHardwareUnit(std::move(PRF));
addHardwareUnit(std::move(LSU));
addHardwareUnit(std::move(HWS));
// Build the pipeline.
auto StagePipeline = std::make_unique<Pipeline>();
StagePipeline->appendStage(std::move(Fetch));
if (Opts.MicroOpQueueSize)
StagePipeline->appendStage(std::make_unique<MicroOpQueueStage>(
Opts.MicroOpQueueSize, Opts.DecodersThroughput));
StagePipeline->appendStage(std::move(Dispatch));
StagePipeline->appendStage(std::move(Execute));
StagePipeline->appendStage(std::move(Retire));
return StagePipeline;
}
std::unique_ptr<Pipeline>
Context::createInOrderPipeline(const PipelineOptions &Opts, SourceMgr &SrcMgr,
CustomBehaviour &CB) {
const MCSchedModel &SM = STI.getSchedModel();
auto PRF = std::make_unique<RegisterFile>(SM, MRI, Opts.RegisterFileSize);
auto LSU = std::make_unique<LSUnit>(SM, Opts.LoadQueueSize,
Opts.StoreQueueSize, Opts.AssumeNoAlias);
// Create the pipeline stages.
auto Entry = std::make_unique<EntryStage>(SrcMgr);
auto InOrderIssue = std::make_unique<InOrderIssueStage>(STI, *PRF, CB, *LSU);
auto StagePipeline = std::make_unique<Pipeline>();
// Pass the ownership of all the hardware units to this Context.
addHardwareUnit(std::move(PRF));
addHardwareUnit(std::move(LSU));
// Build the pipeline.
StagePipeline->appendStage(std::move(Entry));
StagePipeline->appendStage(std::move(InOrderIssue));
return StagePipeline;
}
} // namespace mca
} // namespace llvm