llvm/llvm/utils/TableGen/DFAPacketizerEmitter.cpp

//===- DFAPacketizerEmitter.cpp - Packetization DFA for a VLIW machine ----===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// This class parses the Schedule.td file and produces an API that can be used
// to reason about whether an instruction can be added to a packet on a VLIW
// architecture. The class internally generates a deterministic finite
// automaton (DFA) that models all possible mappings of machine instructions
// to functional units as instructions are added to a packet.
//
//===----------------------------------------------------------------------===//

#include "Common/CodeGenSchedule.h"
#include "Common/CodeGenTarget.h"
#include "DFAEmitter.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/TableGen/Record.h"
#include "llvm/TableGen/TableGenBackend.h"
#include <cassert>
#include <cstdint>
#include <deque>
#include <map>
#include <set>
#include <string>
#include <unordered_map>
#include <vector>

#define DEBUG_TYPE …

usingnamespacellvm;

// We use a uint64_t to represent a resource bitmask.
#define DFA_MAX_RESOURCES …

namespace {
ResourceVector;

struct ScheduleClass { … };

// Generates and prints out the DFA for resource tracking.
class DFAPacketizerEmitter { … };
} // end anonymous namespace

DFAPacketizerEmitter::DFAPacketizerEmitter(const RecordKeeper &R)
    : … { … }

int DFAPacketizerEmitter::collectAllFuncUnits(
    ArrayRef<const CodeGenProcModel *> ProcModels) { … }

int DFAPacketizerEmitter::collectAllComboFuncs(
    ArrayRef<const Record *> ComboFuncList) { … }

ResourceVector
DFAPacketizerEmitter::getResourcesForItinerary(const Record *Itinerary) { … }

void DFAPacketizerEmitter::createScheduleClasses(
    unsigned ItineraryIdx, ArrayRef<const Record *> Itineraries) { … }

//
// Run the worklist algorithm to generate the DFA.
//
void DFAPacketizerEmitter::run(raw_ostream &OS) { … }

void DFAPacketizerEmitter::emitForItineraries(
    raw_ostream &OS, std::vector<const CodeGenProcModel *> &ProcModels,
    std::string DFAName) { … }

static TableGen::Emitter::OptClass<DFAPacketizerEmitter>
    X("gen-dfa-packetizer", "Generate DFA Packetizer for VLIW targets");