Home | History | Annotate | Line # | Download | only in TableGen
      1 //===- SubtargetEmitter.cpp - Generate subtarget enumerations -------------===//
      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 //
      9 // This tablegen backend emits subtarget enumerations.
     10 //
     11 //===----------------------------------------------------------------------===//
     12 
     13 #include "CodeGenTarget.h"
     14 #include "CodeGenSchedule.h"
     15 #include "PredicateExpander.h"
     16 #include "llvm/ADT/SmallPtrSet.h"
     17 #include "llvm/ADT/STLExtras.h"
     18 #include "llvm/ADT/StringExtras.h"
     19 #include "llvm/ADT/StringRef.h"
     20 #include "llvm/MC/MCInstrItineraries.h"
     21 #include "llvm/MC/MCSchedule.h"
     22 #include "llvm/MC/SubtargetFeature.h"
     23 #include "llvm/Support/Debug.h"
     24 #include "llvm/Support/Format.h"
     25 #include "llvm/Support/raw_ostream.h"
     26 #include "llvm/TableGen/Error.h"
     27 #include "llvm/TableGen/Record.h"
     28 #include "llvm/TableGen/TableGenBackend.h"
     29 #include <algorithm>
     30 #include <cassert>
     31 #include <cstdint>
     32 #include <iterator>
     33 #include <map>
     34 #include <string>
     35 #include <vector>
     36 
     37 using namespace llvm;
     38 
     39 #define DEBUG_TYPE "subtarget-emitter"
     40 
     41 namespace {
     42 
     43 class SubtargetEmitter {
     44   // Each processor has a SchedClassDesc table with an entry for each SchedClass.
     45   // The SchedClassDesc table indexes into a global write resource table, write
     46   // latency table, and read advance table.
     47   struct SchedClassTables {
     48     std::vector<std::vector<MCSchedClassDesc>> ProcSchedClasses;
     49     std::vector<MCWriteProcResEntry> WriteProcResources;
     50     std::vector<MCWriteLatencyEntry> WriteLatencies;
     51     std::vector<std::string> WriterNames;
     52     std::vector<MCReadAdvanceEntry> ReadAdvanceEntries;
     53 
     54     // Reserve an invalid entry at index 0
     55     SchedClassTables() {
     56       ProcSchedClasses.resize(1);
     57       WriteProcResources.resize(1);
     58       WriteLatencies.resize(1);
     59       WriterNames.push_back("InvalidWrite");
     60       ReadAdvanceEntries.resize(1);
     61     }
     62   };
     63 
     64   struct LessWriteProcResources {
     65     bool operator()(const MCWriteProcResEntry &LHS,
     66                     const MCWriteProcResEntry &RHS) {
     67       return LHS.ProcResourceIdx < RHS.ProcResourceIdx;
     68     }
     69   };
     70 
     71   const CodeGenTarget &TGT;
     72   RecordKeeper &Records;
     73   CodeGenSchedModels &SchedModels;
     74   std::string Target;
     75 
     76   void Enumeration(raw_ostream &OS, DenseMap<Record *, unsigned> &FeatureMap);
     77   unsigned FeatureKeyValues(raw_ostream &OS,
     78                             const DenseMap<Record *, unsigned> &FeatureMap);
     79   unsigned CPUKeyValues(raw_ostream &OS,
     80                         const DenseMap<Record *, unsigned> &FeatureMap);
     81   void FormItineraryStageString(const std::string &Names,
     82                                 Record *ItinData, std::string &ItinString,
     83                                 unsigned &NStages);
     84   void FormItineraryOperandCycleString(Record *ItinData, std::string &ItinString,
     85                                        unsigned &NOperandCycles);
     86   void FormItineraryBypassString(const std::string &Names,
     87                                  Record *ItinData,
     88                                  std::string &ItinString, unsigned NOperandCycles);
     89   void EmitStageAndOperandCycleData(raw_ostream &OS,
     90                                     std::vector<std::vector<InstrItinerary>>
     91                                       &ProcItinLists);
     92   void EmitItineraries(raw_ostream &OS,
     93                        std::vector<std::vector<InstrItinerary>>
     94                          &ProcItinLists);
     95   unsigned EmitRegisterFileTables(const CodeGenProcModel &ProcModel,
     96                                   raw_ostream &OS);
     97   void EmitLoadStoreQueueInfo(const CodeGenProcModel &ProcModel,
     98                               raw_ostream &OS);
     99   void EmitExtraProcessorInfo(const CodeGenProcModel &ProcModel,
    100                               raw_ostream &OS);
    101   void EmitProcessorProp(raw_ostream &OS, const Record *R, StringRef Name,
    102                          char Separator);
    103   void EmitProcessorResourceSubUnits(const CodeGenProcModel &ProcModel,
    104                                      raw_ostream &OS);
    105   void EmitProcessorResources(const CodeGenProcModel &ProcModel,
    106                               raw_ostream &OS);
    107   Record *FindWriteResources(const CodeGenSchedRW &SchedWrite,
    108                              const CodeGenProcModel &ProcModel);
    109   Record *FindReadAdvance(const CodeGenSchedRW &SchedRead,
    110                           const CodeGenProcModel &ProcModel);
    111   void ExpandProcResources(RecVec &PRVec, std::vector<int64_t> &Cycles,
    112                            const CodeGenProcModel &ProcModel);
    113   void GenSchedClassTables(const CodeGenProcModel &ProcModel,
    114                            SchedClassTables &SchedTables);
    115   void EmitSchedClassTables(SchedClassTables &SchedTables, raw_ostream &OS);
    116   void EmitProcessorModels(raw_ostream &OS);
    117   void EmitSchedModelHelpers(const std::string &ClassName, raw_ostream &OS);
    118   void emitSchedModelHelpersImpl(raw_ostream &OS,
    119                                  bool OnlyExpandMCInstPredicates = false);
    120   void emitGenMCSubtargetInfo(raw_ostream &OS);
    121   void EmitMCInstrAnalysisPredicateFunctions(raw_ostream &OS);
    122 
    123   void EmitSchedModel(raw_ostream &OS);
    124   void EmitHwModeCheck(const std::string &ClassName, raw_ostream &OS);
    125   void ParseFeaturesFunction(raw_ostream &OS, unsigned NumFeatures,
    126                              unsigned NumProcs);
    127 
    128 public:
    129   SubtargetEmitter(RecordKeeper &R, CodeGenTarget &TGT)
    130       : TGT(TGT), Records(R), SchedModels(TGT.getSchedModels()),
    131         Target(TGT.getName()) {}
    132 
    133   void run(raw_ostream &o);
    134 };
    135 
    136 } // end anonymous namespace
    137 
    138 //
    139 // Enumeration - Emit the specified class as an enumeration.
    140 //
    141 void SubtargetEmitter::Enumeration(raw_ostream &OS,
    142                                    DenseMap<Record *, unsigned> &FeatureMap) {
    143   // Get all records of class and sort
    144   std::vector<Record*> DefList =
    145     Records.getAllDerivedDefinitions("SubtargetFeature");
    146   llvm::sort(DefList, LessRecord());
    147 
    148   unsigned N = DefList.size();
    149   if (N == 0)
    150     return;
    151   if (N + 1 > MAX_SUBTARGET_FEATURES)
    152     PrintFatalError("Too many subtarget features! Bump MAX_SUBTARGET_FEATURES.");
    153 
    154   OS << "namespace " << Target << " {\n";
    155 
    156   // Open enumeration.
    157   OS << "enum {\n";
    158 
    159   // For each record
    160   for (unsigned i = 0; i < N; ++i) {
    161     // Next record
    162     Record *Def = DefList[i];
    163 
    164     // Get and emit name
    165     OS << "  " << Def->getName() << " = " << i << ",\n";
    166 
    167     // Save the index for this feature.
    168     FeatureMap[Def] = i;
    169   }
    170 
    171   OS << "  "
    172      << "NumSubtargetFeatures = " << N << "\n";
    173 
    174   // Close enumeration and namespace
    175   OS << "};\n";
    176   OS << "} // end namespace " << Target << "\n";
    177 }
    178 
    179 static void printFeatureMask(raw_ostream &OS, RecVec &FeatureList,
    180                              const DenseMap<Record *, unsigned> &FeatureMap) {
    181   std::array<uint64_t, MAX_SUBTARGET_WORDS> Mask = {};
    182   for (const Record *Feature : FeatureList) {
    183     unsigned Bit = FeatureMap.lookup(Feature);
    184     Mask[Bit / 64] |= 1ULL << (Bit % 64);
    185   }
    186 
    187   OS << "{ { { ";
    188   for (unsigned i = 0; i != Mask.size(); ++i) {
    189     OS << "0x";
    190     OS.write_hex(Mask[i]);
    191     OS << "ULL, ";
    192   }
    193   OS << "} } }";
    194 }
    195 
    196 //
    197 // FeatureKeyValues - Emit data of all the subtarget features.  Used by the
    198 // command line.
    199 //
    200 unsigned SubtargetEmitter::FeatureKeyValues(
    201     raw_ostream &OS, const DenseMap<Record *, unsigned> &FeatureMap) {
    202   // Gather and sort all the features
    203   std::vector<Record*> FeatureList =
    204                            Records.getAllDerivedDefinitions("SubtargetFeature");
    205 
    206   if (FeatureList.empty())
    207     return 0;
    208 
    209   llvm::sort(FeatureList, LessRecordFieldName());
    210 
    211   // Begin feature table
    212   OS << "// Sorted (by key) array of values for CPU features.\n"
    213      << "extern const llvm::SubtargetFeatureKV " << Target
    214      << "FeatureKV[] = {\n";
    215 
    216   // For each feature
    217   unsigned NumFeatures = 0;
    218   for (const Record *Feature : FeatureList) {
    219     // Next feature
    220     StringRef Name = Feature->getName();
    221     StringRef CommandLineName = Feature->getValueAsString("Name");
    222     StringRef Desc = Feature->getValueAsString("Desc");
    223 
    224     if (CommandLineName.empty()) continue;
    225 
    226     // Emit as { "feature", "description", { featureEnum }, { i1 , i2 , ... , in } }
    227     OS << "  { "
    228        << "\"" << CommandLineName << "\", "
    229        << "\"" << Desc << "\", "
    230        << Target << "::" << Name << ", ";
    231 
    232     RecVec ImpliesList = Feature->getValueAsListOfDefs("Implies");
    233 
    234     printFeatureMask(OS, ImpliesList, FeatureMap);
    235 
    236     OS << " },\n";
    237     ++NumFeatures;
    238   }
    239 
    240   // End feature table
    241   OS << "};\n";
    242 
    243   return NumFeatures;
    244 }
    245 
    246 //
    247 // CPUKeyValues - Emit data of all the subtarget processors.  Used by command
    248 // line.
    249 //
    250 unsigned
    251 SubtargetEmitter::CPUKeyValues(raw_ostream &OS,
    252                                const DenseMap<Record *, unsigned> &FeatureMap) {
    253   // Gather and sort processor information
    254   std::vector<Record*> ProcessorList =
    255                           Records.getAllDerivedDefinitions("Processor");
    256   llvm::sort(ProcessorList, LessRecordFieldName());
    257 
    258   // Begin processor table
    259   OS << "// Sorted (by key) array of values for CPU subtype.\n"
    260      << "extern const llvm::SubtargetSubTypeKV " << Target
    261      << "SubTypeKV[] = {\n";
    262 
    263   // For each processor
    264   for (Record *Processor : ProcessorList) {
    265     StringRef Name = Processor->getValueAsString("Name");
    266     RecVec FeatureList = Processor->getValueAsListOfDefs("Features");
    267     RecVec TuneFeatureList = Processor->getValueAsListOfDefs("TuneFeatures");
    268 
    269     // Emit as { "cpu", "description", 0, { f1 , f2 , ... fn } },
    270     OS << " { "
    271        << "\"" << Name << "\", ";
    272 
    273     printFeatureMask(OS, FeatureList, FeatureMap);
    274     OS << ", ";
    275     printFeatureMask(OS, TuneFeatureList, FeatureMap);
    276 
    277     // Emit the scheduler model pointer.
    278     const std::string &ProcModelName =
    279       SchedModels.getModelForProc(Processor).ModelName;
    280     OS << ", &" << ProcModelName << " },\n";
    281   }
    282 
    283   // End processor table
    284   OS << "};\n";
    285 
    286   return ProcessorList.size();
    287 }
    288 
    289 //
    290 // FormItineraryStageString - Compose a string containing the stage
    291 // data initialization for the specified itinerary.  N is the number
    292 // of stages.
    293 //
    294 void SubtargetEmitter::FormItineraryStageString(const std::string &Name,
    295                                                 Record *ItinData,
    296                                                 std::string &ItinString,
    297                                                 unsigned &NStages) {
    298   // Get states list
    299   RecVec StageList = ItinData->getValueAsListOfDefs("Stages");
    300 
    301   // For each stage
    302   unsigned N = NStages = StageList.size();
    303   for (unsigned i = 0; i < N;) {
    304     // Next stage
    305     const Record *Stage = StageList[i];
    306 
    307     // Form string as ,{ cycles, u1 | u2 | ... | un, timeinc, kind }
    308     int Cycles = Stage->getValueAsInt("Cycles");
    309     ItinString += "  { " + itostr(Cycles) + ", ";
    310 
    311     // Get unit list
    312     RecVec UnitList = Stage->getValueAsListOfDefs("Units");
    313 
    314     // For each unit
    315     for (unsigned j = 0, M = UnitList.size(); j < M;) {
    316       // Add name and bitwise or
    317       ItinString += Name + "FU::" + UnitList[j]->getName().str();
    318       if (++j < M) ItinString += " | ";
    319     }
    320 
    321     int TimeInc = Stage->getValueAsInt("TimeInc");
    322     ItinString += ", " + itostr(TimeInc);
    323 
    324     int Kind = Stage->getValueAsInt("Kind");
    325     ItinString += ", (llvm::InstrStage::ReservationKinds)" + itostr(Kind);
    326 
    327     // Close off stage
    328     ItinString += " }";
    329     if (++i < N) ItinString += ", ";
    330   }
    331 }
    332 
    333 //
    334 // FormItineraryOperandCycleString - Compose a string containing the
    335 // operand cycle initialization for the specified itinerary.  N is the
    336 // number of operands that has cycles specified.
    337 //
    338 void SubtargetEmitter::FormItineraryOperandCycleString(Record *ItinData,
    339                          std::string &ItinString, unsigned &NOperandCycles) {
    340   // Get operand cycle list
    341   std::vector<int64_t> OperandCycleList =
    342     ItinData->getValueAsListOfInts("OperandCycles");
    343 
    344   // For each operand cycle
    345   NOperandCycles = OperandCycleList.size();
    346   ListSeparator LS;
    347   for (int OCycle : OperandCycleList) {
    348     // Next operand cycle
    349     ItinString += LS;
    350     ItinString += "  " + itostr(OCycle);
    351   }
    352 }
    353 
    354 void SubtargetEmitter::FormItineraryBypassString(const std::string &Name,
    355                                                  Record *ItinData,
    356                                                  std::string &ItinString,
    357                                                  unsigned NOperandCycles) {
    358   RecVec BypassList = ItinData->getValueAsListOfDefs("Bypasses");
    359   unsigned N = BypassList.size();
    360   unsigned i = 0;
    361   ListSeparator LS;
    362   for (; i < N; ++i) {
    363     ItinString += LS;
    364     ItinString += Name + "Bypass::" + BypassList[i]->getName().str();
    365   }
    366   for (; i < NOperandCycles; ++i) {
    367     ItinString += LS;
    368     ItinString += " 0";
    369   }
    370 }
    371 
    372 //
    373 // EmitStageAndOperandCycleData - Generate unique itinerary stages and operand
    374 // cycle tables. Create a list of InstrItinerary objects (ProcItinLists) indexed
    375 // by CodeGenSchedClass::Index.
    376 //
    377 void SubtargetEmitter::
    378 EmitStageAndOperandCycleData(raw_ostream &OS,
    379                              std::vector<std::vector<InstrItinerary>>
    380                                &ProcItinLists) {
    381   // Multiple processor models may share an itinerary record. Emit it once.
    382   SmallPtrSet<Record*, 8> ItinsDefSet;
    383 
    384   // Emit functional units for all the itineraries.
    385   for (const CodeGenProcModel &ProcModel : SchedModels.procModels()) {
    386 
    387     if (!ItinsDefSet.insert(ProcModel.ItinsDef).second)
    388       continue;
    389 
    390     RecVec FUs = ProcModel.ItinsDef->getValueAsListOfDefs("FU");
    391     if (FUs.empty())
    392       continue;
    393 
    394     StringRef Name = ProcModel.ItinsDef->getName();
    395     OS << "\n// Functional units for \"" << Name << "\"\n"
    396        << "namespace " << Name << "FU {\n";
    397 
    398     for (unsigned j = 0, FUN = FUs.size(); j < FUN; ++j)
    399       OS << "  const InstrStage::FuncUnits " << FUs[j]->getName()
    400          << " = 1ULL << " << j << ";\n";
    401 
    402     OS << "} // end namespace " << Name << "FU\n";
    403 
    404     RecVec BPs = ProcModel.ItinsDef->getValueAsListOfDefs("BP");
    405     if (!BPs.empty()) {
    406       OS << "\n// Pipeline forwarding paths for itineraries \"" << Name
    407          << "\"\n" << "namespace " << Name << "Bypass {\n";
    408 
    409       OS << "  const unsigned NoBypass = 0;\n";
    410       for (unsigned j = 0, BPN = BPs.size(); j < BPN; ++j)
    411         OS << "  const unsigned " << BPs[j]->getName()
    412            << " = 1 << " << j << ";\n";
    413 
    414       OS << "} // end namespace " << Name << "Bypass\n";
    415     }
    416   }
    417 
    418   // Begin stages table
    419   std::string StageTable = "\nextern const llvm::InstrStage " + Target +
    420                            "Stages[] = {\n";
    421   StageTable += "  { 0, 0, 0, llvm::InstrStage::Required }, // No itinerary\n";
    422 
    423   // Begin operand cycle table
    424   std::string OperandCycleTable = "extern const unsigned " + Target +
    425     "OperandCycles[] = {\n";
    426   OperandCycleTable += "  0, // No itinerary\n";
    427 
    428   // Begin pipeline bypass table
    429   std::string BypassTable = "extern const unsigned " + Target +
    430     "ForwardingPaths[] = {\n";
    431   BypassTable += " 0, // No itinerary\n";
    432 
    433   // For each Itinerary across all processors, add a unique entry to the stages,
    434   // operand cycles, and pipeline bypass tables. Then add the new Itinerary
    435   // object with computed offsets to the ProcItinLists result.
    436   unsigned StageCount = 1, OperandCycleCount = 1;
    437   std::map<std::string, unsigned> ItinStageMap, ItinOperandMap;
    438   for (const CodeGenProcModel &ProcModel : SchedModels.procModels()) {
    439     // Add process itinerary to the list.
    440     ProcItinLists.resize(ProcItinLists.size()+1);
    441 
    442     // If this processor defines no itineraries, then leave the itinerary list
    443     // empty.
    444     std::vector<InstrItinerary> &ItinList = ProcItinLists.back();
    445     if (!ProcModel.hasItineraries())
    446       continue;
    447 
    448     StringRef Name = ProcModel.ItinsDef->getName();
    449 
    450     ItinList.resize(SchedModels.numInstrSchedClasses());
    451     assert(ProcModel.ItinDefList.size() == ItinList.size() && "bad Itins");
    452 
    453     for (unsigned SchedClassIdx = 0, SchedClassEnd = ItinList.size();
    454          SchedClassIdx < SchedClassEnd; ++SchedClassIdx) {
    455 
    456       // Next itinerary data
    457       Record *ItinData = ProcModel.ItinDefList[SchedClassIdx];
    458 
    459       // Get string and stage count
    460       std::string ItinStageString;
    461       unsigned NStages = 0;
    462       if (ItinData)
    463         FormItineraryStageString(std::string(Name), ItinData, ItinStageString,
    464                                  NStages);
    465 
    466       // Get string and operand cycle count
    467       std::string ItinOperandCycleString;
    468       unsigned NOperandCycles = 0;
    469       std::string ItinBypassString;
    470       if (ItinData) {
    471         FormItineraryOperandCycleString(ItinData, ItinOperandCycleString,
    472                                         NOperandCycles);
    473 
    474         FormItineraryBypassString(std::string(Name), ItinData, ItinBypassString,
    475                                   NOperandCycles);
    476       }
    477 
    478       // Check to see if stage already exists and create if it doesn't
    479       uint16_t FindStage = 0;
    480       if (NStages > 0) {
    481         FindStage = ItinStageMap[ItinStageString];
    482         if (FindStage == 0) {
    483           // Emit as { cycles, u1 | u2 | ... | un, timeinc }, // indices
    484           StageTable += ItinStageString + ", // " + itostr(StageCount);
    485           if (NStages > 1)
    486             StageTable += "-" + itostr(StageCount + NStages - 1);
    487           StageTable += "\n";
    488           // Record Itin class number.
    489           ItinStageMap[ItinStageString] = FindStage = StageCount;
    490           StageCount += NStages;
    491         }
    492       }
    493 
    494       // Check to see if operand cycle already exists and create if it doesn't
    495       uint16_t FindOperandCycle = 0;
    496       if (NOperandCycles > 0) {
    497         std::string ItinOperandString = ItinOperandCycleString+ItinBypassString;
    498         FindOperandCycle = ItinOperandMap[ItinOperandString];
    499         if (FindOperandCycle == 0) {
    500           // Emit as  cycle, // index
    501           OperandCycleTable += ItinOperandCycleString + ", // ";
    502           std::string OperandIdxComment = itostr(OperandCycleCount);
    503           if (NOperandCycles > 1)
    504             OperandIdxComment += "-"
    505               + itostr(OperandCycleCount + NOperandCycles - 1);
    506           OperandCycleTable += OperandIdxComment + "\n";
    507           // Record Itin class number.
    508           ItinOperandMap[ItinOperandCycleString] =
    509             FindOperandCycle = OperandCycleCount;
    510           // Emit as bypass, // index
    511           BypassTable += ItinBypassString + ", // " + OperandIdxComment + "\n";
    512           OperandCycleCount += NOperandCycles;
    513         }
    514       }
    515 
    516       // Set up itinerary as location and location + stage count
    517       int16_t NumUOps = ItinData ? ItinData->getValueAsInt("NumMicroOps") : 0;
    518       InstrItinerary Intinerary = {
    519           NumUOps,
    520           FindStage,
    521           uint16_t(FindStage + NStages),
    522           FindOperandCycle,
    523           uint16_t(FindOperandCycle + NOperandCycles),
    524       };
    525 
    526       // Inject - empty slots will be 0, 0
    527       ItinList[SchedClassIdx] = Intinerary;
    528     }
    529   }
    530 
    531   // Closing stage
    532   StageTable += "  { 0, 0, 0, llvm::InstrStage::Required } // End stages\n";
    533   StageTable += "};\n";
    534 
    535   // Closing operand cycles
    536   OperandCycleTable += "  0 // End operand cycles\n";
    537   OperandCycleTable += "};\n";
    538 
    539   BypassTable += " 0 // End bypass tables\n";
    540   BypassTable += "};\n";
    541 
    542   // Emit tables.
    543   OS << StageTable;
    544   OS << OperandCycleTable;
    545   OS << BypassTable;
    546 }
    547 
    548 //
    549 // EmitProcessorData - Generate data for processor itineraries that were
    550 // computed during EmitStageAndOperandCycleData(). ProcItinLists lists all
    551 // Itineraries for each processor. The Itinerary lists are indexed on
    552 // CodeGenSchedClass::Index.
    553 //
    554 void SubtargetEmitter::
    555 EmitItineraries(raw_ostream &OS,
    556                 std::vector<std::vector<InstrItinerary>> &ProcItinLists) {
    557   // Multiple processor models may share an itinerary record. Emit it once.
    558   SmallPtrSet<Record*, 8> ItinsDefSet;
    559 
    560   // For each processor's machine model
    561   std::vector<std::vector<InstrItinerary>>::iterator
    562       ProcItinListsIter = ProcItinLists.begin();
    563   for (CodeGenSchedModels::ProcIter PI = SchedModels.procModelBegin(),
    564          PE = SchedModels.procModelEnd(); PI != PE; ++PI, ++ProcItinListsIter) {
    565 
    566     Record *ItinsDef = PI->ItinsDef;
    567     if (!ItinsDefSet.insert(ItinsDef).second)
    568       continue;
    569 
    570     // Get the itinerary list for the processor.
    571     assert(ProcItinListsIter != ProcItinLists.end() && "bad iterator");
    572     std::vector<InstrItinerary> &ItinList = *ProcItinListsIter;
    573 
    574     // Empty itineraries aren't referenced anywhere in the tablegen output
    575     // so don't emit them.
    576     if (ItinList.empty())
    577       continue;
    578 
    579     OS << "\n";
    580     OS << "static const llvm::InstrItinerary ";
    581 
    582     // Begin processor itinerary table
    583     OS << ItinsDef->getName() << "[] = {\n";
    584 
    585     // For each itinerary class in CodeGenSchedClass::Index order.
    586     for (unsigned j = 0, M = ItinList.size(); j < M; ++j) {
    587       InstrItinerary &Intinerary = ItinList[j];
    588 
    589       // Emit Itinerary in the form of
    590       // { firstStage, lastStage, firstCycle, lastCycle } // index
    591       OS << "  { " <<
    592         Intinerary.NumMicroOps << ", " <<
    593         Intinerary.FirstStage << ", " <<
    594         Intinerary.LastStage << ", " <<
    595         Intinerary.FirstOperandCycle << ", " <<
    596         Intinerary.LastOperandCycle << " }" <<
    597         ", // " << j << " " << SchedModels.getSchedClass(j).Name << "\n";
    598     }
    599     // End processor itinerary table
    600     OS << "  { 0, uint16_t(~0U), uint16_t(~0U), uint16_t(~0U), uint16_t(~0U) }"
    601           "// end marker\n";
    602     OS << "};\n";
    603   }
    604 }
    605 
    606 // Emit either the value defined in the TableGen Record, or the default
    607 // value defined in the C++ header. The Record is null if the processor does not
    608 // define a model.
    609 void SubtargetEmitter::EmitProcessorProp(raw_ostream &OS, const Record *R,
    610                                          StringRef Name, char Separator) {
    611   OS << "  ";
    612   int V = R ? R->getValueAsInt(Name) : -1;
    613   if (V >= 0)
    614     OS << V << Separator << " // " << Name;
    615   else
    616     OS << "MCSchedModel::Default" << Name << Separator;
    617   OS << '\n';
    618 }
    619 
    620 void SubtargetEmitter::EmitProcessorResourceSubUnits(
    621     const CodeGenProcModel &ProcModel, raw_ostream &OS) {
    622   OS << "\nstatic const unsigned " << ProcModel.ModelName
    623      << "ProcResourceSubUnits[] = {\n"
    624      << "  0,  // Invalid\n";
    625 
    626   for (unsigned i = 0, e = ProcModel.ProcResourceDefs.size(); i < e; ++i) {
    627     Record *PRDef = ProcModel.ProcResourceDefs[i];
    628     if (!PRDef->isSubClassOf("ProcResGroup"))
    629       continue;
    630     RecVec ResUnits = PRDef->getValueAsListOfDefs("Resources");
    631     for (Record *RUDef : ResUnits) {
    632       Record *const RU =
    633           SchedModels.findProcResUnits(RUDef, ProcModel, PRDef->getLoc());
    634       for (unsigned J = 0; J < RU->getValueAsInt("NumUnits"); ++J) {
    635         OS << "  " << ProcModel.getProcResourceIdx(RU) << ", ";
    636       }
    637     }
    638     OS << "  // " << PRDef->getName() << "\n";
    639   }
    640   OS << "};\n";
    641 }
    642 
    643 static void EmitRetireControlUnitInfo(const CodeGenProcModel &ProcModel,
    644                                       raw_ostream &OS) {
    645   int64_t ReorderBufferSize = 0, MaxRetirePerCycle = 0;
    646   if (Record *RCU = ProcModel.RetireControlUnit) {
    647     ReorderBufferSize =
    648         std::max(ReorderBufferSize, RCU->getValueAsInt("ReorderBufferSize"));
    649     MaxRetirePerCycle =
    650         std::max(MaxRetirePerCycle, RCU->getValueAsInt("MaxRetirePerCycle"));
    651   }
    652 
    653   OS << ReorderBufferSize << ", // ReorderBufferSize\n  ";
    654   OS << MaxRetirePerCycle << ", // MaxRetirePerCycle\n  ";
    655 }
    656 
    657 static void EmitRegisterFileInfo(const CodeGenProcModel &ProcModel,
    658                                  unsigned NumRegisterFiles,
    659                                  unsigned NumCostEntries, raw_ostream &OS) {
    660   if (NumRegisterFiles)
    661     OS << ProcModel.ModelName << "RegisterFiles,\n  " << (1 + NumRegisterFiles);
    662   else
    663     OS << "nullptr,\n  0";
    664 
    665   OS << ", // Number of register files.\n  ";
    666   if (NumCostEntries)
    667     OS << ProcModel.ModelName << "RegisterCosts,\n  ";
    668   else
    669     OS << "nullptr,\n  ";
    670   OS << NumCostEntries << ", // Number of register cost entries.\n";
    671 }
    672 
    673 unsigned
    674 SubtargetEmitter::EmitRegisterFileTables(const CodeGenProcModel &ProcModel,
    675                                          raw_ostream &OS) {
    676   if (llvm::all_of(ProcModel.RegisterFiles, [](const CodeGenRegisterFile &RF) {
    677         return RF.hasDefaultCosts();
    678       }))
    679     return 0;
    680 
    681   // Print the RegisterCost table first.
    682   OS << "\n// {RegisterClassID, Register Cost, AllowMoveElimination }\n";
    683   OS << "static const llvm::MCRegisterCostEntry " << ProcModel.ModelName
    684      << "RegisterCosts"
    685      << "[] = {\n";
    686 
    687   for (const CodeGenRegisterFile &RF : ProcModel.RegisterFiles) {
    688     // Skip register files with a default cost table.
    689     if (RF.hasDefaultCosts())
    690       continue;
    691     // Add entries to the cost table.
    692     for (const CodeGenRegisterCost &RC : RF.Costs) {
    693       OS << "  { ";
    694       Record *Rec = RC.RCDef;
    695       if (Rec->getValue("Namespace"))
    696         OS << Rec->getValueAsString("Namespace") << "::";
    697       OS << Rec->getName() << "RegClassID, " << RC.Cost << ", "
    698          << RC.AllowMoveElimination << "},\n";
    699     }
    700   }
    701   OS << "};\n";
    702 
    703   // Now generate a table with register file info.
    704   OS << "\n // {Name, #PhysRegs, #CostEntries, IndexToCostTbl, "
    705      << "MaxMovesEliminatedPerCycle, AllowZeroMoveEliminationOnly }\n";
    706   OS << "static const llvm::MCRegisterFileDesc " << ProcModel.ModelName
    707      << "RegisterFiles"
    708      << "[] = {\n"
    709      << "  { \"InvalidRegisterFile\", 0, 0, 0, 0, 0 },\n";
    710   unsigned CostTblIndex = 0;
    711 
    712   for (const CodeGenRegisterFile &RD : ProcModel.RegisterFiles) {
    713     OS << "  { ";
    714     OS << '"' << RD.Name << '"' << ", " << RD.NumPhysRegs << ", ";
    715     unsigned NumCostEntries = RD.Costs.size();
    716     OS << NumCostEntries << ", " << CostTblIndex << ", "
    717        << RD.MaxMovesEliminatedPerCycle << ", "
    718        << RD.AllowZeroMoveEliminationOnly << "},\n";
    719     CostTblIndex += NumCostEntries;
    720   }
    721   OS << "};\n";
    722 
    723   return CostTblIndex;
    724 }
    725 
    726 void SubtargetEmitter::EmitLoadStoreQueueInfo(const CodeGenProcModel &ProcModel,
    727                                               raw_ostream &OS) {
    728   unsigned QueueID = 0;
    729   if (ProcModel.LoadQueue) {
    730     const Record *Queue = ProcModel.LoadQueue->getValueAsDef("QueueDescriptor");
    731     QueueID = 1 + std::distance(ProcModel.ProcResourceDefs.begin(),
    732                                 find(ProcModel.ProcResourceDefs, Queue));
    733   }
    734   OS << "  " << QueueID << ", // Resource Descriptor for the Load Queue\n";
    735 
    736   QueueID = 0;
    737   if (ProcModel.StoreQueue) {
    738     const Record *Queue =
    739         ProcModel.StoreQueue->getValueAsDef("QueueDescriptor");
    740     QueueID = 1 + std::distance(ProcModel.ProcResourceDefs.begin(),
    741                                 find(ProcModel.ProcResourceDefs, Queue));
    742   }
    743   OS << "  " << QueueID << ", // Resource Descriptor for the Store Queue\n";
    744 }
    745 
    746 void SubtargetEmitter::EmitExtraProcessorInfo(const CodeGenProcModel &ProcModel,
    747                                               raw_ostream &OS) {
    748   // Generate a table of register file descriptors (one entry per each user
    749   // defined register file), and a table of register costs.
    750   unsigned NumCostEntries = EmitRegisterFileTables(ProcModel, OS);
    751 
    752   // Now generate a table for the extra processor info.
    753   OS << "\nstatic const llvm::MCExtraProcessorInfo " << ProcModel.ModelName
    754      << "ExtraInfo = {\n  ";
    755 
    756   // Add information related to the retire control unit.
    757   EmitRetireControlUnitInfo(ProcModel, OS);
    758 
    759   // Add information related to the register files (i.e. where to find register
    760   // file descriptors and register costs).
    761   EmitRegisterFileInfo(ProcModel, ProcModel.RegisterFiles.size(),
    762                        NumCostEntries, OS);
    763 
    764   // Add information about load/store queues.
    765   EmitLoadStoreQueueInfo(ProcModel, OS);
    766 
    767   OS << "};\n";
    768 }
    769 
    770 void SubtargetEmitter::EmitProcessorResources(const CodeGenProcModel &ProcModel,
    771                                               raw_ostream &OS) {
    772   EmitProcessorResourceSubUnits(ProcModel, OS);
    773 
    774   OS << "\n// {Name, NumUnits, SuperIdx, BufferSize, SubUnitsIdxBegin}\n";
    775   OS << "static const llvm::MCProcResourceDesc " << ProcModel.ModelName
    776      << "ProcResources"
    777      << "[] = {\n"
    778      << "  {\"InvalidUnit\", 0, 0, 0, 0},\n";
    779 
    780   unsigned SubUnitsOffset = 1;
    781   for (unsigned i = 0, e = ProcModel.ProcResourceDefs.size(); i < e; ++i) {
    782     Record *PRDef = ProcModel.ProcResourceDefs[i];
    783 
    784     Record *SuperDef = nullptr;
    785     unsigned SuperIdx = 0;
    786     unsigned NumUnits = 0;
    787     const unsigned SubUnitsBeginOffset = SubUnitsOffset;
    788     int BufferSize = PRDef->getValueAsInt("BufferSize");
    789     if (PRDef->isSubClassOf("ProcResGroup")) {
    790       RecVec ResUnits = PRDef->getValueAsListOfDefs("Resources");
    791       for (Record *RU : ResUnits) {
    792         NumUnits += RU->getValueAsInt("NumUnits");
    793         SubUnitsOffset += RU->getValueAsInt("NumUnits");
    794       }
    795     }
    796     else {
    797       // Find the SuperIdx
    798       if (PRDef->getValueInit("Super")->isComplete()) {
    799         SuperDef =
    800             SchedModels.findProcResUnits(PRDef->getValueAsDef("Super"),
    801                                          ProcModel, PRDef->getLoc());
    802         SuperIdx = ProcModel.getProcResourceIdx(SuperDef);
    803       }
    804       NumUnits = PRDef->getValueAsInt("NumUnits");
    805     }
    806     // Emit the ProcResourceDesc
    807     OS << "  {\"" << PRDef->getName() << "\", ";
    808     if (PRDef->getName().size() < 15)
    809       OS.indent(15 - PRDef->getName().size());
    810     OS << NumUnits << ", " << SuperIdx << ", " << BufferSize << ", ";
    811     if (SubUnitsBeginOffset != SubUnitsOffset) {
    812       OS << ProcModel.ModelName << "ProcResourceSubUnits + "
    813          << SubUnitsBeginOffset;
    814     } else {
    815       OS << "nullptr";
    816     }
    817     OS << "}, // #" << i+1;
    818     if (SuperDef)
    819       OS << ", Super=" << SuperDef->getName();
    820     OS << "\n";
    821   }
    822   OS << "};\n";
    823 }
    824 
    825 // Find the WriteRes Record that defines processor resources for this
    826 // SchedWrite.
    827 Record *SubtargetEmitter::FindWriteResources(
    828   const CodeGenSchedRW &SchedWrite, const CodeGenProcModel &ProcModel) {
    829 
    830   // Check if the SchedWrite is already subtarget-specific and directly
    831   // specifies a set of processor resources.
    832   if (SchedWrite.TheDef->isSubClassOf("SchedWriteRes"))
    833     return SchedWrite.TheDef;
    834 
    835   Record *AliasDef = nullptr;
    836   for (Record *A : SchedWrite.Aliases) {
    837     const CodeGenSchedRW &AliasRW =
    838       SchedModels.getSchedRW(A->getValueAsDef("AliasRW"));
    839     if (AliasRW.TheDef->getValueInit("SchedModel")->isComplete()) {
    840       Record *ModelDef = AliasRW.TheDef->getValueAsDef("SchedModel");
    841       if (&SchedModels.getProcModel(ModelDef) != &ProcModel)
    842         continue;
    843     }
    844     if (AliasDef)
    845       PrintFatalError(AliasRW.TheDef->getLoc(), "Multiple aliases "
    846                     "defined for processor " + ProcModel.ModelName +
    847                     " Ensure only one SchedAlias exists per RW.");
    848     AliasDef = AliasRW.TheDef;
    849   }
    850   if (AliasDef && AliasDef->isSubClassOf("SchedWriteRes"))
    851     return AliasDef;
    852 
    853   // Check this processor's list of write resources.
    854   Record *ResDef = nullptr;
    855   for (Record *WR : ProcModel.WriteResDefs) {
    856     if (!WR->isSubClassOf("WriteRes"))
    857       continue;
    858     if (AliasDef == WR->getValueAsDef("WriteType")
    859         || SchedWrite.TheDef == WR->getValueAsDef("WriteType")) {
    860       if (ResDef) {
    861         PrintFatalError(WR->getLoc(), "Resources are defined for both "
    862                       "SchedWrite and its alias on processor " +
    863                       ProcModel.ModelName);
    864       }
    865       ResDef = WR;
    866     }
    867   }
    868   // TODO: If ProcModel has a base model (previous generation processor),
    869   // then call FindWriteResources recursively with that model here.
    870   if (!ResDef) {
    871     PrintFatalError(ProcModel.ModelDef->getLoc(),
    872                     Twine("Processor does not define resources for ") +
    873                     SchedWrite.TheDef->getName());
    874   }
    875   return ResDef;
    876 }
    877 
    878 /// Find the ReadAdvance record for the given SchedRead on this processor or
    879 /// return NULL.
    880 Record *SubtargetEmitter::FindReadAdvance(const CodeGenSchedRW &SchedRead,
    881                                           const CodeGenProcModel &ProcModel) {
    882   // Check for SchedReads that directly specify a ReadAdvance.
    883   if (SchedRead.TheDef->isSubClassOf("SchedReadAdvance"))
    884     return SchedRead.TheDef;
    885 
    886   // Check this processor's list of aliases for SchedRead.
    887   Record *AliasDef = nullptr;
    888   for (Record *A : SchedRead.Aliases) {
    889     const CodeGenSchedRW &AliasRW =
    890       SchedModels.getSchedRW(A->getValueAsDef("AliasRW"));
    891     if (AliasRW.TheDef->getValueInit("SchedModel")->isComplete()) {
    892       Record *ModelDef = AliasRW.TheDef->getValueAsDef("SchedModel");
    893       if (&SchedModels.getProcModel(ModelDef) != &ProcModel)
    894         continue;
    895     }
    896     if (AliasDef)
    897       PrintFatalError(AliasRW.TheDef->getLoc(), "Multiple aliases "
    898                     "defined for processor " + ProcModel.ModelName +
    899                     " Ensure only one SchedAlias exists per RW.");
    900     AliasDef = AliasRW.TheDef;
    901   }
    902   if (AliasDef && AliasDef->isSubClassOf("SchedReadAdvance"))
    903     return AliasDef;
    904 
    905   // Check this processor's ReadAdvanceList.
    906   Record *ResDef = nullptr;
    907   for (Record *RA : ProcModel.ReadAdvanceDefs) {
    908     if (!RA->isSubClassOf("ReadAdvance"))
    909       continue;
    910     if (AliasDef == RA->getValueAsDef("ReadType")
    911         || SchedRead.TheDef == RA->getValueAsDef("ReadType")) {
    912       if (ResDef) {
    913         PrintFatalError(RA->getLoc(), "Resources are defined for both "
    914                       "SchedRead and its alias on processor " +
    915                       ProcModel.ModelName);
    916       }
    917       ResDef = RA;
    918     }
    919   }
    920   // TODO: If ProcModel has a base model (previous generation processor),
    921   // then call FindReadAdvance recursively with that model here.
    922   if (!ResDef && SchedRead.TheDef->getName() != "ReadDefault") {
    923     PrintFatalError(ProcModel.ModelDef->getLoc(),
    924                     Twine("Processor does not define resources for ") +
    925                     SchedRead.TheDef->getName());
    926   }
    927   return ResDef;
    928 }
    929 
    930 // Expand an explicit list of processor resources into a full list of implied
    931 // resource groups and super resources that cover them.
    932 void SubtargetEmitter::ExpandProcResources(RecVec &PRVec,
    933                                            std::vector<int64_t> &Cycles,
    934                                            const CodeGenProcModel &PM) {
    935   assert(PRVec.size() == Cycles.size() && "failed precondition");
    936   for (unsigned i = 0, e = PRVec.size(); i != e; ++i) {
    937     Record *PRDef = PRVec[i];
    938     RecVec SubResources;
    939     if (PRDef->isSubClassOf("ProcResGroup"))
    940       SubResources = PRDef->getValueAsListOfDefs("Resources");
    941     else {
    942       SubResources.push_back(PRDef);
    943       PRDef = SchedModels.findProcResUnits(PRDef, PM, PRDef->getLoc());
    944       for (Record *SubDef = PRDef;
    945            SubDef->getValueInit("Super")->isComplete();) {
    946         if (SubDef->isSubClassOf("ProcResGroup")) {
    947           // Disallow this for simplicitly.
    948           PrintFatalError(SubDef->getLoc(), "Processor resource group "
    949                           " cannot be a super resources.");
    950         }
    951         Record *SuperDef =
    952             SchedModels.findProcResUnits(SubDef->getValueAsDef("Super"), PM,
    953                                          SubDef->getLoc());
    954         PRVec.push_back(SuperDef);
    955         Cycles.push_back(Cycles[i]);
    956         SubDef = SuperDef;
    957       }
    958     }
    959     for (Record *PR : PM.ProcResourceDefs) {
    960       if (PR == PRDef || !PR->isSubClassOf("ProcResGroup"))
    961         continue;
    962       RecVec SuperResources = PR->getValueAsListOfDefs("Resources");
    963       RecIter SubI = SubResources.begin(), SubE = SubResources.end();
    964       for( ; SubI != SubE; ++SubI) {
    965         if (!is_contained(SuperResources, *SubI)) {
    966           break;
    967         }
    968       }
    969       if (SubI == SubE) {
    970         PRVec.push_back(PR);
    971         Cycles.push_back(Cycles[i]);
    972       }
    973     }
    974   }
    975 }
    976 
    977 // Generate the SchedClass table for this processor and update global
    978 // tables. Must be called for each processor in order.
    979 void SubtargetEmitter::GenSchedClassTables(const CodeGenProcModel &ProcModel,
    980                                            SchedClassTables &SchedTables) {
    981   SchedTables.ProcSchedClasses.resize(SchedTables.ProcSchedClasses.size() + 1);
    982   if (!ProcModel.hasInstrSchedModel())
    983     return;
    984 
    985   std::vector<MCSchedClassDesc> &SCTab = SchedTables.ProcSchedClasses.back();
    986   LLVM_DEBUG(dbgs() << "\n+++ SCHED CLASSES (GenSchedClassTables) +++\n");
    987   for (const CodeGenSchedClass &SC : SchedModels.schedClasses()) {
    988     LLVM_DEBUG(SC.dump(&SchedModels));
    989 
    990     SCTab.resize(SCTab.size() + 1);
    991     MCSchedClassDesc &SCDesc = SCTab.back();
    992     // SCDesc.Name is guarded by NDEBUG
    993     SCDesc.NumMicroOps = 0;
    994     SCDesc.BeginGroup = false;
    995     SCDesc.EndGroup = false;
    996     SCDesc.RetireOOO = false;
    997     SCDesc.WriteProcResIdx = 0;
    998     SCDesc.WriteLatencyIdx = 0;
    999     SCDesc.ReadAdvanceIdx = 0;
   1000 
   1001     // A Variant SchedClass has no resources of its own.
   1002     bool HasVariants = false;
   1003     for (const CodeGenSchedTransition &CGT :
   1004            make_range(SC.Transitions.begin(), SC.Transitions.end())) {
   1005       if (CGT.ProcIndex == ProcModel.Index) {
   1006         HasVariants = true;
   1007         break;
   1008       }
   1009     }
   1010     if (HasVariants) {
   1011       SCDesc.NumMicroOps = MCSchedClassDesc::VariantNumMicroOps;
   1012       continue;
   1013     }
   1014 
   1015     // Determine if the SchedClass is actually reachable on this processor. If
   1016     // not don't try to locate the processor resources, it will fail.
   1017     // If ProcIndices contains 0, this class applies to all processors.
   1018     assert(!SC.ProcIndices.empty() && "expect at least one procidx");
   1019     if (SC.ProcIndices[0] != 0) {
   1020       if (!is_contained(SC.ProcIndices, ProcModel.Index))
   1021         continue;
   1022     }
   1023     IdxVec Writes = SC.Writes;
   1024     IdxVec Reads = SC.Reads;
   1025     if (!SC.InstRWs.empty()) {
   1026       // This class has a default ReadWrite list which can be overridden by
   1027       // InstRW definitions.
   1028       Record *RWDef = nullptr;
   1029       for (Record *RW : SC.InstRWs) {
   1030         Record *RWModelDef = RW->getValueAsDef("SchedModel");
   1031         if (&ProcModel == &SchedModels.getProcModel(RWModelDef)) {
   1032           RWDef = RW;
   1033           break;
   1034         }
   1035       }
   1036       if (RWDef) {
   1037         Writes.clear();
   1038         Reads.clear();
   1039         SchedModels.findRWs(RWDef->getValueAsListOfDefs("OperandReadWrites"),
   1040                             Writes, Reads);
   1041       }
   1042     }
   1043     if (Writes.empty()) {
   1044       // Check this processor's itinerary class resources.
   1045       for (Record *I : ProcModel.ItinRWDefs) {
   1046         RecVec Matched = I->getValueAsListOfDefs("MatchedItinClasses");
   1047         if (is_contained(Matched, SC.ItinClassDef)) {
   1048           SchedModels.findRWs(I->getValueAsListOfDefs("OperandReadWrites"),
   1049                               Writes, Reads);
   1050           break;
   1051         }
   1052       }
   1053       if (Writes.empty()) {
   1054         LLVM_DEBUG(dbgs() << ProcModel.ModelName
   1055                           << " does not have resources for class " << SC.Name
   1056                           << '\n');
   1057         SCDesc.NumMicroOps = MCSchedClassDesc::InvalidNumMicroOps;
   1058       }
   1059     }
   1060     // Sum resources across all operand writes.
   1061     std::vector<MCWriteProcResEntry> WriteProcResources;
   1062     std::vector<MCWriteLatencyEntry> WriteLatencies;
   1063     std::vector<std::string> WriterNames;
   1064     std::vector<MCReadAdvanceEntry> ReadAdvanceEntries;
   1065     for (unsigned W : Writes) {
   1066       IdxVec WriteSeq;
   1067       SchedModels.expandRWSeqForProc(W, WriteSeq, /*IsRead=*/false,
   1068                                      ProcModel);
   1069 
   1070       // For each operand, create a latency entry.
   1071       MCWriteLatencyEntry WLEntry;
   1072       WLEntry.Cycles = 0;
   1073       unsigned WriteID = WriteSeq.back();
   1074       WriterNames.push_back(SchedModels.getSchedWrite(WriteID).Name);
   1075       // If this Write is not referenced by a ReadAdvance, don't distinguish it
   1076       // from other WriteLatency entries.
   1077       if (!SchedModels.hasReadOfWrite(
   1078             SchedModels.getSchedWrite(WriteID).TheDef)) {
   1079         WriteID = 0;
   1080       }
   1081       WLEntry.WriteResourceID = WriteID;
   1082 
   1083       for (unsigned WS : WriteSeq) {
   1084 
   1085         Record *WriteRes =
   1086           FindWriteResources(SchedModels.getSchedWrite(WS), ProcModel);
   1087 
   1088         // Mark the parent class as invalid for unsupported write types.
   1089         if (WriteRes->getValueAsBit("Unsupported")) {
   1090           SCDesc.NumMicroOps = MCSchedClassDesc::InvalidNumMicroOps;
   1091           break;
   1092         }
   1093         WLEntry.Cycles += WriteRes->getValueAsInt("Latency");
   1094         SCDesc.NumMicroOps += WriteRes->getValueAsInt("NumMicroOps");
   1095         SCDesc.BeginGroup |= WriteRes->getValueAsBit("BeginGroup");
   1096         SCDesc.EndGroup |= WriteRes->getValueAsBit("EndGroup");
   1097         SCDesc.BeginGroup |= WriteRes->getValueAsBit("SingleIssue");
   1098         SCDesc.EndGroup |= WriteRes->getValueAsBit("SingleIssue");
   1099         SCDesc.RetireOOO |= WriteRes->getValueAsBit("RetireOOO");
   1100 
   1101         // Create an entry for each ProcResource listed in WriteRes.
   1102         RecVec PRVec = WriteRes->getValueAsListOfDefs("ProcResources");
   1103         std::vector<int64_t> Cycles =
   1104           WriteRes->getValueAsListOfInts("ResourceCycles");
   1105 
   1106         if (Cycles.empty()) {
   1107           // If ResourceCycles is not provided, default to one cycle per
   1108           // resource.
   1109           Cycles.resize(PRVec.size(), 1);
   1110         } else if (Cycles.size() != PRVec.size()) {
   1111           // If ResourceCycles is provided, check consistency.
   1112           PrintFatalError(
   1113               WriteRes->getLoc(),
   1114               Twine("Inconsistent resource cycles: !size(ResourceCycles) != "
   1115                     "!size(ProcResources): ")
   1116                   .concat(Twine(PRVec.size()))
   1117                   .concat(" vs ")
   1118                   .concat(Twine(Cycles.size())));
   1119         }
   1120 
   1121         ExpandProcResources(PRVec, Cycles, ProcModel);
   1122 
   1123         for (unsigned PRIdx = 0, PREnd = PRVec.size();
   1124              PRIdx != PREnd; ++PRIdx) {
   1125           MCWriteProcResEntry WPREntry;
   1126           WPREntry.ProcResourceIdx = ProcModel.getProcResourceIdx(PRVec[PRIdx]);
   1127           assert(WPREntry.ProcResourceIdx && "Bad ProcResourceIdx");
   1128           WPREntry.Cycles = Cycles[PRIdx];
   1129           // If this resource is already used in this sequence, add the current
   1130           // entry's cycles so that the same resource appears to be used
   1131           // serially, rather than multiple parallel uses. This is important for
   1132           // in-order machine where the resource consumption is a hazard.
   1133           unsigned WPRIdx = 0, WPREnd = WriteProcResources.size();
   1134           for( ; WPRIdx != WPREnd; ++WPRIdx) {
   1135             if (WriteProcResources[WPRIdx].ProcResourceIdx
   1136                 == WPREntry.ProcResourceIdx) {
   1137               WriteProcResources[WPRIdx].Cycles += WPREntry.Cycles;
   1138               break;
   1139             }
   1140           }
   1141           if (WPRIdx == WPREnd)
   1142             WriteProcResources.push_back(WPREntry);
   1143         }
   1144       }
   1145       WriteLatencies.push_back(WLEntry);
   1146     }
   1147     // Create an entry for each operand Read in this SchedClass.
   1148     // Entries must be sorted first by UseIdx then by WriteResourceID.
   1149     for (unsigned UseIdx = 0, EndIdx = Reads.size();
   1150          UseIdx != EndIdx; ++UseIdx) {
   1151       Record *ReadAdvance =
   1152         FindReadAdvance(SchedModels.getSchedRead(Reads[UseIdx]), ProcModel);
   1153       if (!ReadAdvance)
   1154         continue;
   1155 
   1156       // Mark the parent class as invalid for unsupported write types.
   1157       if (ReadAdvance->getValueAsBit("Unsupported")) {
   1158         SCDesc.NumMicroOps = MCSchedClassDesc::InvalidNumMicroOps;
   1159         break;
   1160       }
   1161       RecVec ValidWrites = ReadAdvance->getValueAsListOfDefs("ValidWrites");
   1162       IdxVec WriteIDs;
   1163       if (ValidWrites.empty())
   1164         WriteIDs.push_back(0);
   1165       else {
   1166         for (Record *VW : ValidWrites) {
   1167           WriteIDs.push_back(SchedModels.getSchedRWIdx(VW, /*IsRead=*/false));
   1168         }
   1169       }
   1170       llvm::sort(WriteIDs);
   1171       for(unsigned W : WriteIDs) {
   1172         MCReadAdvanceEntry RAEntry;
   1173         RAEntry.UseIdx = UseIdx;
   1174         RAEntry.WriteResourceID = W;
   1175         RAEntry.Cycles = ReadAdvance->getValueAsInt("Cycles");
   1176         ReadAdvanceEntries.push_back(RAEntry);
   1177       }
   1178     }
   1179     if (SCDesc.NumMicroOps == MCSchedClassDesc::InvalidNumMicroOps) {
   1180       WriteProcResources.clear();
   1181       WriteLatencies.clear();
   1182       ReadAdvanceEntries.clear();
   1183     }
   1184     // Add the information for this SchedClass to the global tables using basic
   1185     // compression.
   1186     //
   1187     // WritePrecRes entries are sorted by ProcResIdx.
   1188     llvm::sort(WriteProcResources, LessWriteProcResources());
   1189 
   1190     SCDesc.NumWriteProcResEntries = WriteProcResources.size();
   1191     std::vector<MCWriteProcResEntry>::iterator WPRPos =
   1192       std::search(SchedTables.WriteProcResources.begin(),
   1193                   SchedTables.WriteProcResources.end(),
   1194                   WriteProcResources.begin(), WriteProcResources.end());
   1195     if (WPRPos != SchedTables.WriteProcResources.end())
   1196       SCDesc.WriteProcResIdx = WPRPos - SchedTables.WriteProcResources.begin();
   1197     else {
   1198       SCDesc.WriteProcResIdx = SchedTables.WriteProcResources.size();
   1199       SchedTables.WriteProcResources.insert(WPRPos, WriteProcResources.begin(),
   1200                                             WriteProcResources.end());
   1201     }
   1202     // Latency entries must remain in operand order.
   1203     SCDesc.NumWriteLatencyEntries = WriteLatencies.size();
   1204     std::vector<MCWriteLatencyEntry>::iterator WLPos =
   1205       std::search(SchedTables.WriteLatencies.begin(),
   1206                   SchedTables.WriteLatencies.end(),
   1207                   WriteLatencies.begin(), WriteLatencies.end());
   1208     if (WLPos != SchedTables.WriteLatencies.end()) {
   1209       unsigned idx = WLPos - SchedTables.WriteLatencies.begin();
   1210       SCDesc.WriteLatencyIdx = idx;
   1211       for (unsigned i = 0, e = WriteLatencies.size(); i < e; ++i)
   1212         if (SchedTables.WriterNames[idx + i].find(WriterNames[i]) ==
   1213             std::string::npos) {
   1214           SchedTables.WriterNames[idx + i] += std::string("_") + WriterNames[i];
   1215         }
   1216     }
   1217     else {
   1218       SCDesc.WriteLatencyIdx = SchedTables.WriteLatencies.size();
   1219       llvm::append_range(SchedTables.WriteLatencies, WriteLatencies);
   1220       llvm::append_range(SchedTables.WriterNames, WriterNames);
   1221     }
   1222     // ReadAdvanceEntries must remain in operand order.
   1223     SCDesc.NumReadAdvanceEntries = ReadAdvanceEntries.size();
   1224     std::vector<MCReadAdvanceEntry>::iterator RAPos =
   1225       std::search(SchedTables.ReadAdvanceEntries.begin(),
   1226                   SchedTables.ReadAdvanceEntries.end(),
   1227                   ReadAdvanceEntries.begin(), ReadAdvanceEntries.end());
   1228     if (RAPos != SchedTables.ReadAdvanceEntries.end())
   1229       SCDesc.ReadAdvanceIdx = RAPos - SchedTables.ReadAdvanceEntries.begin();
   1230     else {
   1231       SCDesc.ReadAdvanceIdx = SchedTables.ReadAdvanceEntries.size();
   1232       llvm::append_range(SchedTables.ReadAdvanceEntries, ReadAdvanceEntries);
   1233     }
   1234   }
   1235 }
   1236 
   1237 // Emit SchedClass tables for all processors and associated global tables.
   1238 void SubtargetEmitter::EmitSchedClassTables(SchedClassTables &SchedTables,
   1239                                             raw_ostream &OS) {
   1240   // Emit global WriteProcResTable.
   1241   OS << "\n// {ProcResourceIdx, Cycles}\n"
   1242      << "extern const llvm::MCWriteProcResEntry "
   1243      << Target << "WriteProcResTable[] = {\n"
   1244      << "  { 0,  0}, // Invalid\n";
   1245   for (unsigned WPRIdx = 1, WPREnd = SchedTables.WriteProcResources.size();
   1246        WPRIdx != WPREnd; ++WPRIdx) {
   1247     MCWriteProcResEntry &WPREntry = SchedTables.WriteProcResources[WPRIdx];
   1248     OS << "  {" << format("%2d", WPREntry.ProcResourceIdx) << ", "
   1249        << format("%2d", WPREntry.Cycles) << "}";
   1250     if (WPRIdx + 1 < WPREnd)
   1251       OS << ',';
   1252     OS << " // #" << WPRIdx << '\n';
   1253   }
   1254   OS << "}; // " << Target << "WriteProcResTable\n";
   1255 
   1256   // Emit global WriteLatencyTable.
   1257   OS << "\n// {Cycles, WriteResourceID}\n"
   1258      << "extern const llvm::MCWriteLatencyEntry "
   1259      << Target << "WriteLatencyTable[] = {\n"
   1260      << "  { 0,  0}, // Invalid\n";
   1261   for (unsigned WLIdx = 1, WLEnd = SchedTables.WriteLatencies.size();
   1262        WLIdx != WLEnd; ++WLIdx) {
   1263     MCWriteLatencyEntry &WLEntry = SchedTables.WriteLatencies[WLIdx];
   1264     OS << "  {" << format("%2d", WLEntry.Cycles) << ", "
   1265        << format("%2d", WLEntry.WriteResourceID) << "}";
   1266     if (WLIdx + 1 < WLEnd)
   1267       OS << ',';
   1268     OS << " // #" << WLIdx << " " << SchedTables.WriterNames[WLIdx] << '\n';
   1269   }
   1270   OS << "}; // " << Target << "WriteLatencyTable\n";
   1271 
   1272   // Emit global ReadAdvanceTable.
   1273   OS << "\n// {UseIdx, WriteResourceID, Cycles}\n"
   1274      << "extern const llvm::MCReadAdvanceEntry "
   1275      << Target << "ReadAdvanceTable[] = {\n"
   1276      << "  {0,  0,  0}, // Invalid\n";
   1277   for (unsigned RAIdx = 1, RAEnd = SchedTables.ReadAdvanceEntries.size();
   1278        RAIdx != RAEnd; ++RAIdx) {
   1279     MCReadAdvanceEntry &RAEntry = SchedTables.ReadAdvanceEntries[RAIdx];
   1280     OS << "  {" << RAEntry.UseIdx << ", "
   1281        << format("%2d", RAEntry.WriteResourceID) << ", "
   1282        << format("%2d", RAEntry.Cycles) << "}";
   1283     if (RAIdx + 1 < RAEnd)
   1284       OS << ',';
   1285     OS << " // #" << RAIdx << '\n';
   1286   }
   1287   OS << "}; // " << Target << "ReadAdvanceTable\n";
   1288 
   1289   // Emit a SchedClass table for each processor.
   1290   for (CodeGenSchedModels::ProcIter PI = SchedModels.procModelBegin(),
   1291          PE = SchedModels.procModelEnd(); PI != PE; ++PI) {
   1292     if (!PI->hasInstrSchedModel())
   1293       continue;
   1294 
   1295     std::vector<MCSchedClassDesc> &SCTab =
   1296       SchedTables.ProcSchedClasses[1 + (PI - SchedModels.procModelBegin())];
   1297 
   1298     OS << "\n// {Name, NumMicroOps, BeginGroup, EndGroup, RetireOOO,"
   1299        << " WriteProcResIdx,#, WriteLatencyIdx,#, ReadAdvanceIdx,#}\n";
   1300     OS << "static const llvm::MCSchedClassDesc "
   1301        << PI->ModelName << "SchedClasses[] = {\n";
   1302 
   1303     // The first class is always invalid. We no way to distinguish it except by
   1304     // name and position.
   1305     assert(SchedModels.getSchedClass(0).Name == "NoInstrModel"
   1306            && "invalid class not first");
   1307     OS << "  {DBGFIELD(\"InvalidSchedClass\")  "
   1308        << MCSchedClassDesc::InvalidNumMicroOps
   1309        << ", false, false, false, 0, 0,  0, 0,  0, 0},\n";
   1310 
   1311     for (unsigned SCIdx = 1, SCEnd = SCTab.size(); SCIdx != SCEnd; ++SCIdx) {
   1312       MCSchedClassDesc &MCDesc = SCTab[SCIdx];
   1313       const CodeGenSchedClass &SchedClass = SchedModels.getSchedClass(SCIdx);
   1314       OS << "  {DBGFIELD(\"" << SchedClass.Name << "\") ";
   1315       if (SchedClass.Name.size() < 18)
   1316         OS.indent(18 - SchedClass.Name.size());
   1317       OS << MCDesc.NumMicroOps
   1318          << ", " << ( MCDesc.BeginGroup ? "true" : "false" )
   1319          << ", " << ( MCDesc.EndGroup ? "true" : "false" )
   1320          << ", " << ( MCDesc.RetireOOO ? "true" : "false" )
   1321          << ", " << format("%2d", MCDesc.WriteProcResIdx)
   1322          << ", " << MCDesc.NumWriteProcResEntries
   1323          << ", " << format("%2d", MCDesc.WriteLatencyIdx)
   1324          << ", " << MCDesc.NumWriteLatencyEntries
   1325          << ", " << format("%2d", MCDesc.ReadAdvanceIdx)
   1326          << ", " << MCDesc.NumReadAdvanceEntries
   1327          << "}, // #" << SCIdx << '\n';
   1328     }
   1329     OS << "}; // " << PI->ModelName << "SchedClasses\n";
   1330   }
   1331 }
   1332 
   1333 void SubtargetEmitter::EmitProcessorModels(raw_ostream &OS) {
   1334   // For each processor model.
   1335   for (const CodeGenProcModel &PM : SchedModels.procModels()) {
   1336     // Emit extra processor info if available.
   1337     if (PM.hasExtraProcessorInfo())
   1338       EmitExtraProcessorInfo(PM, OS);
   1339     // Emit processor resource table.
   1340     if (PM.hasInstrSchedModel())
   1341       EmitProcessorResources(PM, OS);
   1342     else if(!PM.ProcResourceDefs.empty())
   1343       PrintFatalError(PM.ModelDef->getLoc(), "SchedMachineModel defines "
   1344                     "ProcResources without defining WriteRes SchedWriteRes");
   1345 
   1346     // Begin processor itinerary properties
   1347     OS << "\n";
   1348     OS << "static const llvm::MCSchedModel " << PM.ModelName << " = {\n";
   1349     EmitProcessorProp(OS, PM.ModelDef, "IssueWidth", ',');
   1350     EmitProcessorProp(OS, PM.ModelDef, "MicroOpBufferSize", ',');
   1351     EmitProcessorProp(OS, PM.ModelDef, "LoopMicroOpBufferSize", ',');
   1352     EmitProcessorProp(OS, PM.ModelDef, "LoadLatency", ',');
   1353     EmitProcessorProp(OS, PM.ModelDef, "HighLatency", ',');
   1354     EmitProcessorProp(OS, PM.ModelDef, "MispredictPenalty", ',');
   1355 
   1356     bool PostRAScheduler =
   1357       (PM.ModelDef ? PM.ModelDef->getValueAsBit("PostRAScheduler") : false);
   1358 
   1359     OS << "  " << (PostRAScheduler ? "true" : "false")  << ", // "
   1360        << "PostRAScheduler\n";
   1361 
   1362     bool CompleteModel =
   1363       (PM.ModelDef ? PM.ModelDef->getValueAsBit("CompleteModel") : false);
   1364 
   1365     OS << "  " << (CompleteModel ? "true" : "false") << ", // "
   1366        << "CompleteModel\n";
   1367 
   1368     OS << "  " << PM.Index << ", // Processor ID\n";
   1369     if (PM.hasInstrSchedModel())
   1370       OS << "  " << PM.ModelName << "ProcResources" << ",\n"
   1371          << "  " << PM.ModelName << "SchedClasses" << ",\n"
   1372          << "  " << PM.ProcResourceDefs.size()+1 << ",\n"
   1373          << "  " << (SchedModels.schedClassEnd()
   1374                      - SchedModels.schedClassBegin()) << ",\n";
   1375     else
   1376       OS << "  nullptr, nullptr, 0, 0,"
   1377          << " // No instruction-level machine model.\n";
   1378     if (PM.hasItineraries())
   1379       OS << "  " << PM.ItinsDef->getName() << ",\n";
   1380     else
   1381       OS << "  nullptr, // No Itinerary\n";
   1382     if (PM.hasExtraProcessorInfo())
   1383       OS << "  &" << PM.ModelName << "ExtraInfo,\n";
   1384     else
   1385       OS << "  nullptr // No extra processor descriptor\n";
   1386     OS << "};\n";
   1387   }
   1388 }
   1389 
   1390 //
   1391 // EmitSchedModel - Emits all scheduling model tables, folding common patterns.
   1392 //
   1393 void SubtargetEmitter::EmitSchedModel(raw_ostream &OS) {
   1394   OS << "#ifdef DBGFIELD\n"
   1395      << "#error \"<target>GenSubtargetInfo.inc requires a DBGFIELD macro\"\n"
   1396      << "#endif\n"
   1397      << "#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)\n"
   1398      << "#define DBGFIELD(x) x,\n"
   1399      << "#else\n"
   1400      << "#define DBGFIELD(x)\n"
   1401      << "#endif\n";
   1402 
   1403   if (SchedModels.hasItineraries()) {
   1404     std::vector<std::vector<InstrItinerary>> ProcItinLists;
   1405     // Emit the stage data
   1406     EmitStageAndOperandCycleData(OS, ProcItinLists);
   1407     EmitItineraries(OS, ProcItinLists);
   1408   }
   1409   OS << "\n// ===============================================================\n"
   1410      << "// Data tables for the new per-operand machine model.\n";
   1411 
   1412   SchedClassTables SchedTables;
   1413   for (const CodeGenProcModel &ProcModel : SchedModels.procModels()) {
   1414     GenSchedClassTables(ProcModel, SchedTables);
   1415   }
   1416   EmitSchedClassTables(SchedTables, OS);
   1417 
   1418   OS << "\n#undef DBGFIELD\n";
   1419 
   1420   // Emit the processor machine model
   1421   EmitProcessorModels(OS);
   1422 }
   1423 
   1424 static void emitPredicateProlog(const RecordKeeper &Records, raw_ostream &OS) {
   1425   std::string Buffer;
   1426   raw_string_ostream Stream(Buffer);
   1427 
   1428   // Collect all the PredicateProlog records and print them to the output
   1429   // stream.
   1430   std::vector<Record *> Prologs =
   1431       Records.getAllDerivedDefinitions("PredicateProlog");
   1432   llvm::sort(Prologs, LessRecord());
   1433   for (Record *P : Prologs)
   1434     Stream << P->getValueAsString("Code") << '\n';
   1435 
   1436   Stream.flush();
   1437   OS << Buffer;
   1438 }
   1439 
   1440 static bool isTruePredicate(const Record *Rec) {
   1441   return Rec->isSubClassOf("MCSchedPredicate") &&
   1442          Rec->getValueAsDef("Pred")->isSubClassOf("MCTrue");
   1443 }
   1444 
   1445 static void emitPredicates(const CodeGenSchedTransition &T,
   1446                            const CodeGenSchedClass &SC, PredicateExpander &PE,
   1447                            raw_ostream &OS) {
   1448   std::string Buffer;
   1449   raw_string_ostream SS(Buffer);
   1450 
   1451   // If not all predicates are MCTrue, then we need an if-stmt.
   1452   unsigned NumNonTruePreds =
   1453       T.PredTerm.size() - count_if(T.PredTerm, isTruePredicate);
   1454 
   1455   SS.indent(PE.getIndentLevel() * 2);
   1456 
   1457   if (NumNonTruePreds) {
   1458     bool FirstNonTruePredicate = true;
   1459     SS << "if (";
   1460 
   1461     PE.setIndentLevel(PE.getIndentLevel() + 2);
   1462 
   1463     for (const Record *Rec : T.PredTerm) {
   1464       // Skip predicates that evaluate to "true".
   1465       if (isTruePredicate(Rec))
   1466         continue;
   1467 
   1468       if (FirstNonTruePredicate) {
   1469         FirstNonTruePredicate = false;
   1470       } else {
   1471         SS << "\n";
   1472         SS.indent(PE.getIndentLevel() * 2);
   1473         SS << "&& ";
   1474       }
   1475 
   1476       if (Rec->isSubClassOf("MCSchedPredicate")) {
   1477         PE.expandPredicate(SS, Rec->getValueAsDef("Pred"));
   1478         continue;
   1479       }
   1480 
   1481       // Expand this legacy predicate and wrap it around braces if there is more
   1482       // than one predicate to expand.
   1483       SS << ((NumNonTruePreds > 1) ? "(" : "")
   1484          << Rec->getValueAsString("Predicate")
   1485          << ((NumNonTruePreds > 1) ? ")" : "");
   1486     }
   1487 
   1488     SS << ")\n"; // end of if-stmt
   1489     PE.decreaseIndentLevel();
   1490     SS.indent(PE.getIndentLevel() * 2);
   1491     PE.decreaseIndentLevel();
   1492   }
   1493 
   1494   SS << "return " << T.ToClassIdx << "; // " << SC.Name << '\n';
   1495   SS.flush();
   1496   OS << Buffer;
   1497 }
   1498 
   1499 // Used by method `SubtargetEmitter::emitSchedModelHelpersImpl()` to generate
   1500 // epilogue code for the auto-generated helper.
   1501 static void emitSchedModelHelperEpilogue(raw_ostream &OS,
   1502                                          bool ShouldReturnZero) {
   1503   if (ShouldReturnZero) {
   1504     OS << "  // Don't know how to resolve this scheduling class.\n"
   1505        << "  return 0;\n";
   1506     return;
   1507   }
   1508 
   1509   OS << "  report_fatal_error(\"Expected a variant SchedClass\");\n";
   1510 }
   1511 
   1512 static bool hasMCSchedPredicates(const CodeGenSchedTransition &T) {
   1513   return all_of(T.PredTerm, [](const Record *Rec) {
   1514     return Rec->isSubClassOf("MCSchedPredicate");
   1515   });
   1516 }
   1517 
   1518 static void collectVariantClasses(const CodeGenSchedModels &SchedModels,
   1519                                   IdxVec &VariantClasses,
   1520                                   bool OnlyExpandMCInstPredicates) {
   1521   for (const CodeGenSchedClass &SC : SchedModels.schedClasses()) {
   1522     // Ignore non-variant scheduling classes.
   1523     if (SC.Transitions.empty())
   1524       continue;
   1525 
   1526     if (OnlyExpandMCInstPredicates) {
   1527       // Ignore this variant scheduling class no transitions use any meaningful
   1528       // MCSchedPredicate definitions.
   1529       if (!any_of(SC.Transitions, [](const CodeGenSchedTransition &T) {
   1530             return hasMCSchedPredicates(T);
   1531           }))
   1532         continue;
   1533     }
   1534 
   1535     VariantClasses.push_back(SC.Index);
   1536   }
   1537 }
   1538 
   1539 static void collectProcessorIndices(const CodeGenSchedClass &SC,
   1540                                     IdxVec &ProcIndices) {
   1541   // A variant scheduling class may define transitions for multiple
   1542   // processors.  This function identifies wich processors are associated with
   1543   // transition rules specified by variant class `SC`.
   1544   for (const CodeGenSchedTransition &T : SC.Transitions) {
   1545     IdxVec PI;
   1546     std::set_union(&T.ProcIndex, &T.ProcIndex + 1, ProcIndices.begin(),
   1547                    ProcIndices.end(), std::back_inserter(PI));
   1548     ProcIndices.swap(PI);
   1549   }
   1550 }
   1551 
   1552 static bool isAlwaysTrue(const CodeGenSchedTransition &T) {
   1553   return llvm::all_of(T.PredTerm,
   1554                       [](const Record *R) { return isTruePredicate(R); });
   1555 }
   1556 
   1557 void SubtargetEmitter::emitSchedModelHelpersImpl(
   1558     raw_ostream &OS, bool OnlyExpandMCInstPredicates) {
   1559   IdxVec VariantClasses;
   1560   collectVariantClasses(SchedModels, VariantClasses,
   1561                         OnlyExpandMCInstPredicates);
   1562 
   1563   if (VariantClasses.empty()) {
   1564     emitSchedModelHelperEpilogue(OS, OnlyExpandMCInstPredicates);
   1565     return;
   1566   }
   1567 
   1568   // Construct a switch statement where the condition is a check on the
   1569   // scheduling class identifier. There is a `case` for every variant class
   1570   // defined by the processor models of this target.
   1571   // Each `case` implements a number of rules to resolve (i.e. to transition from)
   1572   // a variant scheduling class to another scheduling class.  Rules are
   1573   // described by instances of CodeGenSchedTransition. Note that transitions may
   1574   // not be valid for all processors.
   1575   OS << "  switch (SchedClass) {\n";
   1576   for (unsigned VC : VariantClasses) {
   1577     IdxVec ProcIndices;
   1578     const CodeGenSchedClass &SC = SchedModels.getSchedClass(VC);
   1579     collectProcessorIndices(SC, ProcIndices);
   1580 
   1581     OS << "  case " << VC << ": // " << SC.Name << '\n';
   1582 
   1583     PredicateExpander PE(Target);
   1584     PE.setByRef(false);
   1585     PE.setExpandForMC(OnlyExpandMCInstPredicates);
   1586     for (unsigned PI : ProcIndices) {
   1587       OS << "    ";
   1588 
   1589       // Emit a guard on the processor ID.
   1590       if (PI != 0) {
   1591         OS << (OnlyExpandMCInstPredicates
   1592                    ? "if (CPUID == "
   1593                    : "if (SchedModel->getProcessorID() == ");
   1594         OS << PI << ") ";
   1595         OS << "{ // " << (SchedModels.procModelBegin() + PI)->ModelName << '\n';
   1596       }
   1597 
   1598       // Now emit transitions associated with processor PI.
   1599       const CodeGenSchedTransition *FinalT = nullptr;
   1600       for (const CodeGenSchedTransition &T : SC.Transitions) {
   1601         if (PI != 0 && T.ProcIndex != PI)
   1602           continue;
   1603 
   1604         // Emit only transitions based on MCSchedPredicate, if it's the case.
   1605         // At least the transition specified by NoSchedPred is emitted,
   1606         // which becomes the default transition for those variants otherwise
   1607         // not based on MCSchedPredicate.
   1608         // FIXME: preferably, llvm-mca should instead assume a reasonable
   1609         // default when a variant transition is not based on MCSchedPredicate
   1610         // for a given processor.
   1611         if (OnlyExpandMCInstPredicates && !hasMCSchedPredicates(T))
   1612           continue;
   1613 
   1614         // If transition is folded to 'return X' it should be the last one.
   1615         if (isAlwaysTrue(T)) {
   1616           FinalT = &T;
   1617           continue;
   1618         }
   1619         PE.setIndentLevel(3);
   1620         emitPredicates(T, SchedModels.getSchedClass(T.ToClassIdx), PE, OS);
   1621       }
   1622       if (FinalT)
   1623         emitPredicates(*FinalT, SchedModels.getSchedClass(FinalT->ToClassIdx),
   1624                        PE, OS);
   1625 
   1626       OS << "    }\n";
   1627 
   1628       if (PI == 0)
   1629         break;
   1630     }
   1631 
   1632     if (SC.isInferred())
   1633       OS << "    return " << SC.Index << ";\n";
   1634     OS << "    break;\n";
   1635   }
   1636 
   1637   OS << "  };\n";
   1638 
   1639   emitSchedModelHelperEpilogue(OS, OnlyExpandMCInstPredicates);
   1640 }
   1641 
   1642 void SubtargetEmitter::EmitSchedModelHelpers(const std::string &ClassName,
   1643                                              raw_ostream &OS) {
   1644   OS << "unsigned " << ClassName
   1645      << "\n::resolveSchedClass(unsigned SchedClass, const MachineInstr *MI,"
   1646      << " const TargetSchedModel *SchedModel) const {\n";
   1647 
   1648   // Emit the predicate prolog code.
   1649   emitPredicateProlog(Records, OS);
   1650 
   1651   // Emit target predicates.
   1652   emitSchedModelHelpersImpl(OS);
   1653 
   1654   OS << "} // " << ClassName << "::resolveSchedClass\n\n";
   1655 
   1656   OS << "unsigned " << ClassName
   1657      << "\n::resolveVariantSchedClass(unsigned SchedClass, const MCInst *MI,"
   1658      << " const MCInstrInfo *MCII, unsigned CPUID) const {\n"
   1659      << "  return " << Target << "_MC"
   1660      << "::resolveVariantSchedClassImpl(SchedClass, MI, MCII, CPUID);\n"
   1661      << "} // " << ClassName << "::resolveVariantSchedClass\n\n";
   1662 
   1663   STIPredicateExpander PE(Target);
   1664   PE.setClassPrefix(ClassName);
   1665   PE.setExpandDefinition(true);
   1666   PE.setByRef(false);
   1667   PE.setIndentLevel(0);
   1668 
   1669   for (const STIPredicateFunction &Fn : SchedModels.getSTIPredicates())
   1670     PE.expandSTIPredicate(OS, Fn);
   1671 }
   1672 
   1673 void SubtargetEmitter::EmitHwModeCheck(const std::string &ClassName,
   1674                                        raw_ostream &OS) {
   1675   const CodeGenHwModes &CGH = TGT.getHwModes();
   1676   assert(CGH.getNumModeIds() > 0);
   1677   if (CGH.getNumModeIds() == 1)
   1678     return;
   1679 
   1680   OS << "unsigned " << ClassName << "::getHwMode() const {\n";
   1681   for (unsigned M = 1, NumModes = CGH.getNumModeIds(); M != NumModes; ++M) {
   1682     const HwMode &HM = CGH.getMode(M);
   1683     OS << "  if (checkFeatures(\"" << HM.Features
   1684        << "\")) return " << M << ";\n";
   1685   }
   1686   OS << "  return 0;\n}\n";
   1687 }
   1688 
   1689 //
   1690 // ParseFeaturesFunction - Produces a subtarget specific function for parsing
   1691 // the subtarget features string.
   1692 //
   1693 void SubtargetEmitter::ParseFeaturesFunction(raw_ostream &OS,
   1694                                              unsigned NumFeatures,
   1695                                              unsigned NumProcs) {
   1696   std::vector<Record*> Features =
   1697                        Records.getAllDerivedDefinitions("SubtargetFeature");
   1698   llvm::sort(Features, LessRecord());
   1699 
   1700   OS << "// ParseSubtargetFeatures - Parses features string setting specified\n"
   1701      << "// subtarget options.\n"
   1702      << "void llvm::";
   1703   OS << Target;
   1704   OS << "Subtarget::ParseSubtargetFeatures(StringRef CPU, StringRef TuneCPU, "
   1705      << "StringRef FS) {\n"
   1706      << "  LLVM_DEBUG(dbgs() << \"\\nFeatures:\" << FS);\n"
   1707      << "  LLVM_DEBUG(dbgs() << \"\\nCPU:\" << CPU);\n"
   1708      << "  LLVM_DEBUG(dbgs() << \"\\nTuneCPU:\" << TuneCPU << \"\\n\\n\");\n";
   1709 
   1710   if (Features.empty()) {
   1711     OS << "}\n";
   1712     return;
   1713   }
   1714 
   1715   OS << "  InitMCProcessorInfo(CPU, TuneCPU, FS);\n"
   1716      << "  const FeatureBitset &Bits = getFeatureBits();\n";
   1717 
   1718   for (Record *R : Features) {
   1719     // Next record
   1720     StringRef Instance = R->getName();
   1721     StringRef Value = R->getValueAsString("Value");
   1722     StringRef Attribute = R->getValueAsString("Attribute");
   1723 
   1724     if (Value=="true" || Value=="false")
   1725       OS << "  if (Bits[" << Target << "::"
   1726          << Instance << "]) "
   1727          << Attribute << " = " << Value << ";\n";
   1728     else
   1729       OS << "  if (Bits[" << Target << "::"
   1730          << Instance << "] && "
   1731          << Attribute << " < " << Value << ") "
   1732          << Attribute << " = " << Value << ";\n";
   1733   }
   1734 
   1735   OS << "}\n";
   1736 }
   1737 
   1738 void SubtargetEmitter::emitGenMCSubtargetInfo(raw_ostream &OS) {
   1739   OS << "namespace " << Target << "_MC {\n"
   1740      << "unsigned resolveVariantSchedClassImpl(unsigned SchedClass,\n"
   1741      << "    const MCInst *MI, const MCInstrInfo *MCII, unsigned CPUID) {\n";
   1742   emitSchedModelHelpersImpl(OS, /* OnlyExpandMCPredicates */ true);
   1743   OS << "}\n";
   1744   OS << "} // end namespace " << Target << "_MC\n\n";
   1745 
   1746   OS << "struct " << Target
   1747      << "GenMCSubtargetInfo : public MCSubtargetInfo {\n";
   1748   OS << "  " << Target << "GenMCSubtargetInfo(const Triple &TT,\n"
   1749      << "    StringRef CPU, StringRef TuneCPU, StringRef FS,\n"
   1750      << "    ArrayRef<SubtargetFeatureKV> PF,\n"
   1751      << "    ArrayRef<SubtargetSubTypeKV> PD,\n"
   1752      << "    const MCWriteProcResEntry *WPR,\n"
   1753      << "    const MCWriteLatencyEntry *WL,\n"
   1754      << "    const MCReadAdvanceEntry *RA, const InstrStage *IS,\n"
   1755      << "    const unsigned *OC, const unsigned *FP) :\n"
   1756      << "      MCSubtargetInfo(TT, CPU, TuneCPU, FS, PF, PD,\n"
   1757      << "                      WPR, WL, RA, IS, OC, FP) { }\n\n"
   1758      << "  unsigned resolveVariantSchedClass(unsigned SchedClass,\n"
   1759      << "      const MCInst *MI, const MCInstrInfo *MCII,\n"
   1760      << "      unsigned CPUID) const override {\n"
   1761      << "    return " << Target << "_MC"
   1762      << "::resolveVariantSchedClassImpl(SchedClass, MI, MCII, CPUID);\n";
   1763   OS << "  }\n";
   1764   if (TGT.getHwModes().getNumModeIds() > 1)
   1765     OS << "  unsigned getHwMode() const override;\n";
   1766   OS << "};\n";
   1767   EmitHwModeCheck(Target + "GenMCSubtargetInfo", OS);
   1768 }
   1769 
   1770 void SubtargetEmitter::EmitMCInstrAnalysisPredicateFunctions(raw_ostream &OS) {
   1771   OS << "\n#ifdef GET_STIPREDICATE_DECLS_FOR_MC_ANALYSIS\n";
   1772   OS << "#undef GET_STIPREDICATE_DECLS_FOR_MC_ANALYSIS\n\n";
   1773 
   1774   STIPredicateExpander PE(Target);
   1775   PE.setExpandForMC(true);
   1776   PE.setByRef(true);
   1777   for (const STIPredicateFunction &Fn : SchedModels.getSTIPredicates())
   1778     PE.expandSTIPredicate(OS, Fn);
   1779 
   1780   OS << "#endif // GET_STIPREDICATE_DECLS_FOR_MC_ANALYSIS\n\n";
   1781 
   1782   OS << "\n#ifdef GET_STIPREDICATE_DEFS_FOR_MC_ANALYSIS\n";
   1783   OS << "#undef GET_STIPREDICATE_DEFS_FOR_MC_ANALYSIS\n\n";
   1784 
   1785   std::string ClassPrefix = Target + "MCInstrAnalysis";
   1786   PE.setExpandDefinition(true);
   1787   PE.setClassPrefix(ClassPrefix);
   1788   PE.setIndentLevel(0);
   1789   for (const STIPredicateFunction &Fn : SchedModels.getSTIPredicates())
   1790     PE.expandSTIPredicate(OS, Fn);
   1791 
   1792   OS << "#endif // GET_STIPREDICATE_DEFS_FOR_MC_ANALYSIS\n\n";
   1793 }
   1794 
   1795 //
   1796 // SubtargetEmitter::run - Main subtarget enumeration emitter.
   1797 //
   1798 void SubtargetEmitter::run(raw_ostream &OS) {
   1799   emitSourceFileHeader("Subtarget Enumeration Source Fragment", OS);
   1800 
   1801   OS << "\n#ifdef GET_SUBTARGETINFO_ENUM\n";
   1802   OS << "#undef GET_SUBTARGETINFO_ENUM\n\n";
   1803 
   1804   DenseMap<Record *, unsigned> FeatureMap;
   1805 
   1806   OS << "namespace llvm {\n";
   1807   Enumeration(OS, FeatureMap);
   1808   OS << "} // end namespace llvm\n\n";
   1809   OS << "#endif // GET_SUBTARGETINFO_ENUM\n\n";
   1810 
   1811   OS << "\n#ifdef GET_SUBTARGETINFO_MC_DESC\n";
   1812   OS << "#undef GET_SUBTARGETINFO_MC_DESC\n\n";
   1813 
   1814   OS << "namespace llvm {\n";
   1815 #if 0
   1816   OS << "namespace {\n";
   1817 #endif
   1818   unsigned NumFeatures = FeatureKeyValues(OS, FeatureMap);
   1819   OS << "\n";
   1820   EmitSchedModel(OS);
   1821   OS << "\n";
   1822   unsigned NumProcs = CPUKeyValues(OS, FeatureMap);
   1823   OS << "\n";
   1824 #if 0
   1825   OS << "} // end anonymous namespace\n\n";
   1826 #endif
   1827 
   1828   // MCInstrInfo initialization routine.
   1829   emitGenMCSubtargetInfo(OS);
   1830 
   1831   OS << "\nstatic inline MCSubtargetInfo *create" << Target
   1832      << "MCSubtargetInfoImpl("
   1833      << "const Triple &TT, StringRef CPU, StringRef TuneCPU, StringRef FS) {\n";
   1834   OS << "  return new " << Target
   1835      << "GenMCSubtargetInfo(TT, CPU, TuneCPU, FS, ";
   1836   if (NumFeatures)
   1837     OS << Target << "FeatureKV, ";
   1838   else
   1839     OS << "None, ";
   1840   if (NumProcs)
   1841     OS << Target << "SubTypeKV, ";
   1842   else
   1843     OS << "None, ";
   1844   OS << '\n'; OS.indent(22);
   1845   OS << Target << "WriteProcResTable, "
   1846      << Target << "WriteLatencyTable, "
   1847      << Target << "ReadAdvanceTable, ";
   1848   OS << '\n'; OS.indent(22);
   1849   if (SchedModels.hasItineraries()) {
   1850     OS << Target << "Stages, "
   1851        << Target << "OperandCycles, "
   1852        << Target << "ForwardingPaths";
   1853   } else
   1854     OS << "nullptr, nullptr, nullptr";
   1855   OS << ");\n}\n\n";
   1856 
   1857   OS << "} // end namespace llvm\n\n";
   1858 
   1859   OS << "#endif // GET_SUBTARGETINFO_MC_DESC\n\n";
   1860 
   1861   OS << "\n#ifdef GET_SUBTARGETINFO_TARGET_DESC\n";
   1862   OS << "#undef GET_SUBTARGETINFO_TARGET_DESC\n\n";
   1863 
   1864   OS << "#include \"llvm/Support/Debug.h\"\n";
   1865   OS << "#include \"llvm/Support/raw_ostream.h\"\n\n";
   1866   ParseFeaturesFunction(OS, NumFeatures, NumProcs);
   1867 
   1868   OS << "#endif // GET_SUBTARGETINFO_TARGET_DESC\n\n";
   1869 
   1870   // Create a TargetSubtargetInfo subclass to hide the MC layer initialization.
   1871   OS << "\n#ifdef GET_SUBTARGETINFO_HEADER\n";
   1872   OS << "#undef GET_SUBTARGETINFO_HEADER\n\n";
   1873 
   1874   std::string ClassName = Target + "GenSubtargetInfo";
   1875   OS << "namespace llvm {\n";
   1876   OS << "class DFAPacketizer;\n";
   1877   OS << "namespace " << Target << "_MC {\n"
   1878      << "unsigned resolveVariantSchedClassImpl(unsigned SchedClass,"
   1879      << " const MCInst *MI, const MCInstrInfo *MCII, unsigned CPUID);\n"
   1880      << "} // end namespace " << Target << "_MC\n\n";
   1881   OS << "struct " << ClassName << " : public TargetSubtargetInfo {\n"
   1882      << "  explicit " << ClassName << "(const Triple &TT, StringRef CPU, "
   1883      << "StringRef TuneCPU, StringRef FS);\n"
   1884      << "public:\n"
   1885      << "  unsigned resolveSchedClass(unsigned SchedClass, "
   1886      << " const MachineInstr *DefMI,"
   1887      << " const TargetSchedModel *SchedModel) const override;\n"
   1888      << "  unsigned resolveVariantSchedClass(unsigned SchedClass,"
   1889      << " const MCInst *MI, const MCInstrInfo *MCII,"
   1890      << " unsigned CPUID) const override;\n"
   1891      << "  DFAPacketizer *createDFAPacketizer(const InstrItineraryData *IID)"
   1892      << " const;\n";
   1893   if (TGT.getHwModes().getNumModeIds() > 1)
   1894     OS << "  unsigned getHwMode() const override;\n";
   1895 
   1896   STIPredicateExpander PE(Target);
   1897   PE.setByRef(false);
   1898   for (const STIPredicateFunction &Fn : SchedModels.getSTIPredicates())
   1899     PE.expandSTIPredicate(OS, Fn);
   1900 
   1901   OS << "};\n"
   1902      << "} // end namespace llvm\n\n";
   1903 
   1904   OS << "#endif // GET_SUBTARGETINFO_HEADER\n\n";
   1905 
   1906   OS << "\n#ifdef GET_SUBTARGETINFO_CTOR\n";
   1907   OS << "#undef GET_SUBTARGETINFO_CTOR\n\n";
   1908 
   1909   OS << "#include \"llvm/CodeGen/TargetSchedule.h\"\n\n";
   1910   OS << "namespace llvm {\n";
   1911   OS << "extern const llvm::SubtargetFeatureKV " << Target << "FeatureKV[];\n";
   1912   OS << "extern const llvm::SubtargetSubTypeKV " << Target << "SubTypeKV[];\n";
   1913   OS << "extern const llvm::MCWriteProcResEntry "
   1914      << Target << "WriteProcResTable[];\n";
   1915   OS << "extern const llvm::MCWriteLatencyEntry "
   1916      << Target << "WriteLatencyTable[];\n";
   1917   OS << "extern const llvm::MCReadAdvanceEntry "
   1918      << Target << "ReadAdvanceTable[];\n";
   1919 
   1920   if (SchedModels.hasItineraries()) {
   1921     OS << "extern const llvm::InstrStage " << Target << "Stages[];\n";
   1922     OS << "extern const unsigned " << Target << "OperandCycles[];\n";
   1923     OS << "extern const unsigned " << Target << "ForwardingPaths[];\n";
   1924   }
   1925 
   1926   OS << ClassName << "::" << ClassName << "(const Triple &TT, StringRef CPU, "
   1927      << "StringRef TuneCPU, StringRef FS)\n"
   1928      << "  : TargetSubtargetInfo(TT, CPU, TuneCPU, FS, ";
   1929   if (NumFeatures)
   1930     OS << "makeArrayRef(" << Target << "FeatureKV, " << NumFeatures << "), ";
   1931   else
   1932     OS << "None, ";
   1933   if (NumProcs)
   1934     OS << "makeArrayRef(" << Target << "SubTypeKV, " << NumProcs << "), ";
   1935   else
   1936     OS << "None, ";
   1937   OS << '\n'; OS.indent(24);
   1938   OS << Target << "WriteProcResTable, "
   1939      << Target << "WriteLatencyTable, "
   1940      << Target << "ReadAdvanceTable, ";
   1941   OS << '\n'; OS.indent(24);
   1942   if (SchedModels.hasItineraries()) {
   1943     OS << Target << "Stages, "
   1944        << Target << "OperandCycles, "
   1945        << Target << "ForwardingPaths";
   1946   } else
   1947     OS << "nullptr, nullptr, nullptr";
   1948   OS << ") {}\n\n";
   1949 
   1950   EmitSchedModelHelpers(ClassName, OS);
   1951   EmitHwModeCheck(ClassName, OS);
   1952 
   1953   OS << "} // end namespace llvm\n\n";
   1954 
   1955   OS << "#endif // GET_SUBTARGETINFO_CTOR\n\n";
   1956 
   1957   EmitMCInstrAnalysisPredicateFunctions(OS);
   1958 }
   1959 
   1960 namespace llvm {
   1961 
   1962 void EmitSubtarget(RecordKeeper &RK, raw_ostream &OS) {
   1963   CodeGenTarget CGTarget(RK);
   1964   SubtargetEmitter(RK, CGTarget).run(OS);
   1965 }
   1966 
   1967 } // end namespace llvm
   1968