1 //===- SubtargetEmitter.cpp - Generate subtarget enumerations -------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This tablegen backend emits subtarget enumerations.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "CodeGenTarget.h"
15 #include "CodeGenSchedule.h"
16 #include "PredicateExpander.h"
17 #include "llvm/ADT/SmallPtrSet.h"
18 #include "llvm/ADT/STLExtras.h"
19 #include "llvm/ADT/StringExtras.h"
20 #include "llvm/ADT/StringRef.h"
21 #include "llvm/MC/MCInstrItineraries.h"
22 #include "llvm/MC/MCSchedule.h"
23 #include "llvm/MC/SubtargetFeature.h"
24 #include "llvm/Support/Debug.h"
25 #include "llvm/Support/Format.h"
26 #include "llvm/Support/raw_ostream.h"
27 #include "llvm/TableGen/Error.h"
28 #include "llvm/TableGen/Record.h"
29 #include "llvm/TableGen/TableGenBackend.h"
30 #include <algorithm>
31 #include <cassert>
32 #include <cstdint>
33 #include <iterator>
34 #include <map>
35 #include <string>
36 #include <vector>
37 
38 using namespace llvm;
39 
40 #define DEBUG_TYPE "subtarget-emitter"
41 
42 namespace {
43 
44 class SubtargetEmitter {
45   // Each processor has a SchedClassDesc table with an entry for each SchedClass.
46   // The SchedClassDesc table indexes into a global write resource table, write
47   // latency table, and read advance table.
48   struct SchedClassTables {
49     std::vector<std::vector<MCSchedClassDesc>> ProcSchedClasses;
50     std::vector<MCWriteProcResEntry> WriteProcResources;
51     std::vector<MCWriteLatencyEntry> WriteLatencies;
52     std::vector<std::string> WriterNames;
53     std::vector<MCReadAdvanceEntry> ReadAdvanceEntries;
54 
55     // Reserve an invalid entry at index 0
SchedClassTables__anon21f9a14b0111::SubtargetEmitter::SchedClassTables56     SchedClassTables() {
57       ProcSchedClasses.resize(1);
58       WriteProcResources.resize(1);
59       WriteLatencies.resize(1);
60       WriterNames.push_back("InvalidWrite");
61       ReadAdvanceEntries.resize(1);
62     }
63   };
64 
65   struct LessWriteProcResources {
operator ()__anon21f9a14b0111::SubtargetEmitter::LessWriteProcResources66     bool operator()(const MCWriteProcResEntry &LHS,
67                     const MCWriteProcResEntry &RHS) {
68       return LHS.ProcResourceIdx < RHS.ProcResourceIdx;
69     }
70   };
71 
72   const CodeGenTarget &TGT;
73   RecordKeeper &Records;
74   CodeGenSchedModels &SchedModels;
75   std::string Target;
76 
77   void Enumeration(raw_ostream &OS);
78   unsigned FeatureKeyValues(raw_ostream &OS);
79   unsigned CPUKeyValues(raw_ostream &OS);
80   void FormItineraryStageString(const std::string &Names,
81                                 Record *ItinData, std::string &ItinString,
82                                 unsigned &NStages);
83   void FormItineraryOperandCycleString(Record *ItinData, std::string &ItinString,
84                                        unsigned &NOperandCycles);
85   void FormItineraryBypassString(const std::string &Names,
86                                  Record *ItinData,
87                                  std::string &ItinString, unsigned NOperandCycles);
88   void EmitStageAndOperandCycleData(raw_ostream &OS,
89                                     std::vector<std::vector<InstrItinerary>>
90                                       &ProcItinLists);
91   void EmitItineraries(raw_ostream &OS,
92                        std::vector<std::vector<InstrItinerary>>
93                          &ProcItinLists);
94   unsigned EmitRegisterFileTables(const CodeGenProcModel &ProcModel,
95                                   raw_ostream &OS);
96   void EmitLoadStoreQueueInfo(const CodeGenProcModel &ProcModel,
97                               raw_ostream &OS);
98   void EmitExtraProcessorInfo(const CodeGenProcModel &ProcModel,
99                               raw_ostream &OS);
100   void EmitProcessorProp(raw_ostream &OS, const Record *R, StringRef Name,
101                          char Separator);
102   void EmitProcessorResourceSubUnits(const CodeGenProcModel &ProcModel,
103                                      raw_ostream &OS);
104   void EmitProcessorResources(const CodeGenProcModel &ProcModel,
105                               raw_ostream &OS);
106   Record *FindWriteResources(const CodeGenSchedRW &SchedWrite,
107                              const CodeGenProcModel &ProcModel);
108   Record *FindReadAdvance(const CodeGenSchedRW &SchedRead,
109                           const CodeGenProcModel &ProcModel);
110   void ExpandProcResources(RecVec &PRVec, std::vector<int64_t> &Cycles,
111                            const CodeGenProcModel &ProcModel);
112   void GenSchedClassTables(const CodeGenProcModel &ProcModel,
113                            SchedClassTables &SchedTables);
114   void EmitSchedClassTables(SchedClassTables &SchedTables, raw_ostream &OS);
115   void EmitProcessorModels(raw_ostream &OS);
116   void EmitProcessorLookup(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:
SubtargetEmitter(RecordKeeper & R,CodeGenTarget & TGT)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 //
Enumeration(raw_ostream & OS)141 void SubtargetEmitter::Enumeration(raw_ostream &OS) {
142   // Get all records of class and sort
143   std::vector<Record*> DefList =
144     Records.getAllDerivedDefinitions("SubtargetFeature");
145   llvm::sort(DefList, LessRecord());
146 
147   unsigned N = DefList.size();
148   if (N == 0)
149     return;
150   if (N > MAX_SUBTARGET_FEATURES)
151     PrintFatalError("Too many subtarget features! Bump MAX_SUBTARGET_FEATURES.");
152 
153   OS << "namespace " << Target << " {\n";
154 
155   // Open enumeration.
156   OS << "enum {\n";
157 
158   // For each record
159   for (unsigned i = 0; i < N; ++i) {
160     // Next record
161     Record *Def = DefList[i];
162 
163     // Get and emit name
164     OS << "  " << Def->getName() << " = " << i << ",\n";
165   }
166 
167   // Close enumeration and namespace
168   OS << "};\n";
169   OS << "} // end namespace " << Target << "\n";
170 }
171 
172 //
173 // FeatureKeyValues - Emit data of all the subtarget features.  Used by the
174 // command line.
175 //
FeatureKeyValues(raw_ostream & OS)176 unsigned SubtargetEmitter::FeatureKeyValues(raw_ostream &OS) {
177   // Gather and sort all the features
178   std::vector<Record*> FeatureList =
179                            Records.getAllDerivedDefinitions("SubtargetFeature");
180 
181   if (FeatureList.empty())
182     return 0;
183 
184   llvm::sort(FeatureList, LessRecordFieldName());
185 
186   // Begin feature table
187   OS << "// Sorted (by key) array of values for CPU features.\n"
188      << "extern const llvm::SubtargetFeatureKV " << Target
189      << "FeatureKV[] = {\n";
190 
191   // For each feature
192   unsigned NumFeatures = 0;
193   for (unsigned i = 0, N = FeatureList.size(); i < N; ++i) {
194     // Next feature
195     Record *Feature = FeatureList[i];
196 
197     StringRef Name = Feature->getName();
198     StringRef CommandLineName = Feature->getValueAsString("Name");
199     StringRef Desc = Feature->getValueAsString("Desc");
200 
201     if (CommandLineName.empty()) continue;
202 
203     // Emit as { "feature", "description", { featureEnum }, { i1 , i2 , ... , in } }
204     OS << "  { "
205        << "\"" << CommandLineName << "\", "
206        << "\"" << Desc << "\", "
207        << "{ " << Target << "::" << Name << " }, ";
208 
209     RecVec ImpliesList = Feature->getValueAsListOfDefs("Implies");
210 
211     OS << "{";
212     for (unsigned j = 0, M = ImpliesList.size(); j < M;) {
213       OS << " " << Target << "::" << ImpliesList[j]->getName();
214       if (++j < M) OS << ",";
215     }
216     OS << " } },\n";
217     ++NumFeatures;
218   }
219 
220   // End feature table
221   OS << "};\n";
222 
223   return NumFeatures;
224 }
225 
226 //
227 // CPUKeyValues - Emit data of all the subtarget processors.  Used by command
228 // line.
229 //
CPUKeyValues(raw_ostream & OS)230 unsigned SubtargetEmitter::CPUKeyValues(raw_ostream &OS) {
231   // Gather and sort processor information
232   std::vector<Record*> ProcessorList =
233                           Records.getAllDerivedDefinitions("Processor");
234   llvm::sort(ProcessorList, LessRecordFieldName());
235 
236   // Begin processor table
237   OS << "// Sorted (by key) array of values for CPU subtype.\n"
238      << "extern const llvm::SubtargetFeatureKV " << Target
239      << "SubTypeKV[] = {\n";
240 
241   // For each processor
242   for (Record *Processor : ProcessorList) {
243     StringRef Name = Processor->getValueAsString("Name");
244     RecVec FeatureList = Processor->getValueAsListOfDefs("Features");
245 
246     // Emit as { "cpu", "description", { f1 , f2 , ... fn } },
247     OS << "  { "
248        << "\"" << Name << "\", "
249        << "\"Select the " << Name << " processor\", ";
250 
251     OS << "{";
252     for (unsigned j = 0, M = FeatureList.size(); j < M;) {
253       OS << " " << Target << "::" << FeatureList[j]->getName();
254       if (++j < M) OS << ",";
255     }
256     // The { } is for the "implies" section of this data structure.
257     OS << " }, { } },\n";
258   }
259 
260   // End processor table
261   OS << "};\n";
262 
263   return ProcessorList.size();
264 }
265 
266 //
267 // FormItineraryStageString - Compose a string containing the stage
268 // data initialization for the specified itinerary.  N is the number
269 // of stages.
270 //
FormItineraryStageString(const std::string & Name,Record * ItinData,std::string & ItinString,unsigned & NStages)271 void SubtargetEmitter::FormItineraryStageString(const std::string &Name,
272                                                 Record *ItinData,
273                                                 std::string &ItinString,
274                                                 unsigned &NStages) {
275   // Get states list
276   RecVec StageList = ItinData->getValueAsListOfDefs("Stages");
277 
278   // For each stage
279   unsigned N = NStages = StageList.size();
280   for (unsigned i = 0; i < N;) {
281     // Next stage
282     const Record *Stage = StageList[i];
283 
284     // Form string as ,{ cycles, u1 | u2 | ... | un, timeinc, kind }
285     int Cycles = Stage->getValueAsInt("Cycles");
286     ItinString += "  { " + itostr(Cycles) + ", ";
287 
288     // Get unit list
289     RecVec UnitList = Stage->getValueAsListOfDefs("Units");
290 
291     // For each unit
292     for (unsigned j = 0, M = UnitList.size(); j < M;) {
293       // Add name and bitwise or
294       ItinString += Name + "FU::" + UnitList[j]->getName().str();
295       if (++j < M) ItinString += " | ";
296     }
297 
298     int TimeInc = Stage->getValueAsInt("TimeInc");
299     ItinString += ", " + itostr(TimeInc);
300 
301     int Kind = Stage->getValueAsInt("Kind");
302     ItinString += ", (llvm::InstrStage::ReservationKinds)" + itostr(Kind);
303 
304     // Close off stage
305     ItinString += " }";
306     if (++i < N) ItinString += ", ";
307   }
308 }
309 
310 //
311 // FormItineraryOperandCycleString - Compose a string containing the
312 // operand cycle initialization for the specified itinerary.  N is the
313 // number of operands that has cycles specified.
314 //
FormItineraryOperandCycleString(Record * ItinData,std::string & ItinString,unsigned & NOperandCycles)315 void SubtargetEmitter::FormItineraryOperandCycleString(Record *ItinData,
316                          std::string &ItinString, unsigned &NOperandCycles) {
317   // Get operand cycle list
318   std::vector<int64_t> OperandCycleList =
319     ItinData->getValueAsListOfInts("OperandCycles");
320 
321   // For each operand cycle
322   unsigned N = NOperandCycles = OperandCycleList.size();
323   for (unsigned i = 0; i < N;) {
324     // Next operand cycle
325     const int OCycle = OperandCycleList[i];
326 
327     ItinString += "  " + itostr(OCycle);
328     if (++i < N) ItinString += ", ";
329   }
330 }
331 
FormItineraryBypassString(const std::string & Name,Record * ItinData,std::string & ItinString,unsigned NOperandCycles)332 void SubtargetEmitter::FormItineraryBypassString(const std::string &Name,
333                                                  Record *ItinData,
334                                                  std::string &ItinString,
335                                                  unsigned NOperandCycles) {
336   RecVec BypassList = ItinData->getValueAsListOfDefs("Bypasses");
337   unsigned N = BypassList.size();
338   unsigned i = 0;
339   for (; i < N;) {
340     ItinString += Name + "Bypass::" + BypassList[i]->getName().str();
341     if (++i < NOperandCycles) ItinString += ", ";
342   }
343   for (; i < NOperandCycles;) {
344     ItinString += " 0";
345     if (++i < NOperandCycles) ItinString += ", ";
346   }
347 }
348 
349 //
350 // EmitStageAndOperandCycleData - Generate unique itinerary stages and operand
351 // cycle tables. Create a list of InstrItinerary objects (ProcItinLists) indexed
352 // by CodeGenSchedClass::Index.
353 //
354 void SubtargetEmitter::
EmitStageAndOperandCycleData(raw_ostream & OS,std::vector<std::vector<InstrItinerary>> & ProcItinLists)355 EmitStageAndOperandCycleData(raw_ostream &OS,
356                              std::vector<std::vector<InstrItinerary>>
357                                &ProcItinLists) {
358   // Multiple processor models may share an itinerary record. Emit it once.
359   SmallPtrSet<Record*, 8> ItinsDefSet;
360 
361   // Emit functional units for all the itineraries.
362   for (const CodeGenProcModel &ProcModel : SchedModels.procModels()) {
363 
364     if (!ItinsDefSet.insert(ProcModel.ItinsDef).second)
365       continue;
366 
367     RecVec FUs = ProcModel.ItinsDef->getValueAsListOfDefs("FU");
368     if (FUs.empty())
369       continue;
370 
371     StringRef Name = ProcModel.ItinsDef->getName();
372     OS << "\n// Functional units for \"" << Name << "\"\n"
373        << "namespace " << Name << "FU {\n";
374 
375     for (unsigned j = 0, FUN = FUs.size(); j < FUN; ++j)
376       OS << "  const unsigned " << FUs[j]->getName()
377          << " = 1 << " << j << ";\n";
378 
379     OS << "} // end namespace " << Name << "FU\n";
380 
381     RecVec BPs = ProcModel.ItinsDef->getValueAsListOfDefs("BP");
382     if (!BPs.empty()) {
383       OS << "\n// Pipeline forwarding paths for itineraries \"" << Name
384          << "\"\n" << "namespace " << Name << "Bypass {\n";
385 
386       OS << "  const unsigned NoBypass = 0;\n";
387       for (unsigned j = 0, BPN = BPs.size(); j < BPN; ++j)
388         OS << "  const unsigned " << BPs[j]->getName()
389            << " = 1 << " << j << ";\n";
390 
391       OS << "} // end namespace " << Name << "Bypass\n";
392     }
393   }
394 
395   // Begin stages table
396   std::string StageTable = "\nextern const llvm::InstrStage " + Target +
397                            "Stages[] = {\n";
398   StageTable += "  { 0, 0, 0, llvm::InstrStage::Required }, // No itinerary\n";
399 
400   // Begin operand cycle table
401   std::string OperandCycleTable = "extern const unsigned " + Target +
402     "OperandCycles[] = {\n";
403   OperandCycleTable += "  0, // No itinerary\n";
404 
405   // Begin pipeline bypass table
406   std::string BypassTable = "extern const unsigned " + Target +
407     "ForwardingPaths[] = {\n";
408   BypassTable += " 0, // No itinerary\n";
409 
410   // For each Itinerary across all processors, add a unique entry to the stages,
411   // operand cycles, and pipeline bypass tables. Then add the new Itinerary
412   // object with computed offsets to the ProcItinLists result.
413   unsigned StageCount = 1, OperandCycleCount = 1;
414   std::map<std::string, unsigned> ItinStageMap, ItinOperandMap;
415   for (const CodeGenProcModel &ProcModel : SchedModels.procModels()) {
416     // Add process itinerary to the list.
417     ProcItinLists.resize(ProcItinLists.size()+1);
418 
419     // If this processor defines no itineraries, then leave the itinerary list
420     // empty.
421     std::vector<InstrItinerary> &ItinList = ProcItinLists.back();
422     if (!ProcModel.hasItineraries())
423       continue;
424 
425     StringRef Name = ProcModel.ItinsDef->getName();
426 
427     ItinList.resize(SchedModels.numInstrSchedClasses());
428     assert(ProcModel.ItinDefList.size() == ItinList.size() && "bad Itins");
429 
430     for (unsigned SchedClassIdx = 0, SchedClassEnd = ItinList.size();
431          SchedClassIdx < SchedClassEnd; ++SchedClassIdx) {
432 
433       // Next itinerary data
434       Record *ItinData = ProcModel.ItinDefList[SchedClassIdx];
435 
436       // Get string and stage count
437       std::string ItinStageString;
438       unsigned NStages = 0;
439       if (ItinData)
440         FormItineraryStageString(Name, ItinData, ItinStageString, NStages);
441 
442       // Get string and operand cycle count
443       std::string ItinOperandCycleString;
444       unsigned NOperandCycles = 0;
445       std::string ItinBypassString;
446       if (ItinData) {
447         FormItineraryOperandCycleString(ItinData, ItinOperandCycleString,
448                                         NOperandCycles);
449 
450         FormItineraryBypassString(Name, ItinData, ItinBypassString,
451                                   NOperandCycles);
452       }
453 
454       // Check to see if stage already exists and create if it doesn't
455       uint16_t FindStage = 0;
456       if (NStages > 0) {
457         FindStage = ItinStageMap[ItinStageString];
458         if (FindStage == 0) {
459           // Emit as { cycles, u1 | u2 | ... | un, timeinc }, // indices
460           StageTable += ItinStageString + ", // " + itostr(StageCount);
461           if (NStages > 1)
462             StageTable += "-" + itostr(StageCount + NStages - 1);
463           StageTable += "\n";
464           // Record Itin class number.
465           ItinStageMap[ItinStageString] = FindStage = StageCount;
466           StageCount += NStages;
467         }
468       }
469 
470       // Check to see if operand cycle already exists and create if it doesn't
471       uint16_t FindOperandCycle = 0;
472       if (NOperandCycles > 0) {
473         std::string ItinOperandString = ItinOperandCycleString+ItinBypassString;
474         FindOperandCycle = ItinOperandMap[ItinOperandString];
475         if (FindOperandCycle == 0) {
476           // Emit as  cycle, // index
477           OperandCycleTable += ItinOperandCycleString + ", // ";
478           std::string OperandIdxComment = itostr(OperandCycleCount);
479           if (NOperandCycles > 1)
480             OperandIdxComment += "-"
481               + itostr(OperandCycleCount + NOperandCycles - 1);
482           OperandCycleTable += OperandIdxComment + "\n";
483           // Record Itin class number.
484           ItinOperandMap[ItinOperandCycleString] =
485             FindOperandCycle = OperandCycleCount;
486           // Emit as bypass, // index
487           BypassTable += ItinBypassString + ", // " + OperandIdxComment + "\n";
488           OperandCycleCount += NOperandCycles;
489         }
490       }
491 
492       // Set up itinerary as location and location + stage count
493       int16_t NumUOps = ItinData ? ItinData->getValueAsInt("NumMicroOps") : 0;
494       InstrItinerary Intinerary = {
495           NumUOps,
496           FindStage,
497           uint16_t(FindStage + NStages),
498           FindOperandCycle,
499           uint16_t(FindOperandCycle + NOperandCycles),
500       };
501 
502       // Inject - empty slots will be 0, 0
503       ItinList[SchedClassIdx] = Intinerary;
504     }
505   }
506 
507   // Closing stage
508   StageTable += "  { 0, 0, 0, llvm::InstrStage::Required } // End stages\n";
509   StageTable += "};\n";
510 
511   // Closing operand cycles
512   OperandCycleTable += "  0 // End operand cycles\n";
513   OperandCycleTable += "};\n";
514 
515   BypassTable += " 0 // End bypass tables\n";
516   BypassTable += "};\n";
517 
518   // Emit tables.
519   OS << StageTable;
520   OS << OperandCycleTable;
521   OS << BypassTable;
522 }
523 
524 //
525 // EmitProcessorData - Generate data for processor itineraries that were
526 // computed during EmitStageAndOperandCycleData(). ProcItinLists lists all
527 // Itineraries for each processor. The Itinerary lists are indexed on
528 // CodeGenSchedClass::Index.
529 //
530 void SubtargetEmitter::
EmitItineraries(raw_ostream & OS,std::vector<std::vector<InstrItinerary>> & ProcItinLists)531 EmitItineraries(raw_ostream &OS,
532                 std::vector<std::vector<InstrItinerary>> &ProcItinLists) {
533   // Multiple processor models may share an itinerary record. Emit it once.
534   SmallPtrSet<Record*, 8> ItinsDefSet;
535 
536   // For each processor's machine model
537   std::vector<std::vector<InstrItinerary>>::iterator
538       ProcItinListsIter = ProcItinLists.begin();
539   for (CodeGenSchedModels::ProcIter PI = SchedModels.procModelBegin(),
540          PE = SchedModels.procModelEnd(); PI != PE; ++PI, ++ProcItinListsIter) {
541 
542     Record *ItinsDef = PI->ItinsDef;
543     if (!ItinsDefSet.insert(ItinsDef).second)
544       continue;
545 
546     // Get the itinerary list for the processor.
547     assert(ProcItinListsIter != ProcItinLists.end() && "bad iterator");
548     std::vector<InstrItinerary> &ItinList = *ProcItinListsIter;
549 
550     // Empty itineraries aren't referenced anywhere in the tablegen output
551     // so don't emit them.
552     if (ItinList.empty())
553       continue;
554 
555     OS << "\n";
556     OS << "static const llvm::InstrItinerary ";
557 
558     // Begin processor itinerary table
559     OS << ItinsDef->getName() << "[] = {\n";
560 
561     // For each itinerary class in CodeGenSchedClass::Index order.
562     for (unsigned j = 0, M = ItinList.size(); j < M; ++j) {
563       InstrItinerary &Intinerary = ItinList[j];
564 
565       // Emit Itinerary in the form of
566       // { firstStage, lastStage, firstCycle, lastCycle } // index
567       OS << "  { " <<
568         Intinerary.NumMicroOps << ", " <<
569         Intinerary.FirstStage << ", " <<
570         Intinerary.LastStage << ", " <<
571         Intinerary.FirstOperandCycle << ", " <<
572         Intinerary.LastOperandCycle << " }" <<
573         ", // " << j << " " << SchedModels.getSchedClass(j).Name << "\n";
574     }
575     // End processor itinerary table
576     OS << "  { 0, uint16_t(~0U), uint16_t(~0U), uint16_t(~0U), uint16_t(~0U) }"
577           "// end marker\n";
578     OS << "};\n";
579   }
580 }
581 
582 // Emit either the value defined in the TableGen Record, or the default
583 // value defined in the C++ header. The Record is null if the processor does not
584 // define a model.
EmitProcessorProp(raw_ostream & OS,const Record * R,StringRef Name,char Separator)585 void SubtargetEmitter::EmitProcessorProp(raw_ostream &OS, const Record *R,
586                                          StringRef Name, char Separator) {
587   OS << "  ";
588   int V = R ? R->getValueAsInt(Name) : -1;
589   if (V >= 0)
590     OS << V << Separator << " // " << Name;
591   else
592     OS << "MCSchedModel::Default" << Name << Separator;
593   OS << '\n';
594 }
595 
EmitProcessorResourceSubUnits(const CodeGenProcModel & ProcModel,raw_ostream & OS)596 void SubtargetEmitter::EmitProcessorResourceSubUnits(
597     const CodeGenProcModel &ProcModel, raw_ostream &OS) {
598   OS << "\nstatic const unsigned " << ProcModel.ModelName
599      << "ProcResourceSubUnits[] = {\n"
600      << "  0,  // Invalid\n";
601 
602   for (unsigned i = 0, e = ProcModel.ProcResourceDefs.size(); i < e; ++i) {
603     Record *PRDef = ProcModel.ProcResourceDefs[i];
604     if (!PRDef->isSubClassOf("ProcResGroup"))
605       continue;
606     RecVec ResUnits = PRDef->getValueAsListOfDefs("Resources");
607     for (Record *RUDef : ResUnits) {
608       Record *const RU =
609           SchedModels.findProcResUnits(RUDef, ProcModel, PRDef->getLoc());
610       for (unsigned J = 0; J < RU->getValueAsInt("NumUnits"); ++J) {
611         OS << "  " << ProcModel.getProcResourceIdx(RU) << ", ";
612       }
613     }
614     OS << "  // " << PRDef->getName() << "\n";
615   }
616   OS << "};\n";
617 }
618 
EmitRetireControlUnitInfo(const CodeGenProcModel & ProcModel,raw_ostream & OS)619 static void EmitRetireControlUnitInfo(const CodeGenProcModel &ProcModel,
620                                       raw_ostream &OS) {
621   int64_t ReorderBufferSize = 0, MaxRetirePerCycle = 0;
622   if (Record *RCU = ProcModel.RetireControlUnit) {
623     ReorderBufferSize =
624         std::max(ReorderBufferSize, RCU->getValueAsInt("ReorderBufferSize"));
625     MaxRetirePerCycle =
626         std::max(MaxRetirePerCycle, RCU->getValueAsInt("MaxRetirePerCycle"));
627   }
628 
629   OS << ReorderBufferSize << ", // ReorderBufferSize\n  ";
630   OS << MaxRetirePerCycle << ", // MaxRetirePerCycle\n  ";
631 }
632 
EmitRegisterFileInfo(const CodeGenProcModel & ProcModel,unsigned NumRegisterFiles,unsigned NumCostEntries,raw_ostream & OS)633 static void EmitRegisterFileInfo(const CodeGenProcModel &ProcModel,
634                                  unsigned NumRegisterFiles,
635                                  unsigned NumCostEntries, raw_ostream &OS) {
636   if (NumRegisterFiles)
637     OS << ProcModel.ModelName << "RegisterFiles,\n  " << (1 + NumRegisterFiles);
638   else
639     OS << "nullptr,\n  0";
640 
641   OS << ", // Number of register files.\n  ";
642   if (NumCostEntries)
643     OS << ProcModel.ModelName << "RegisterCosts,\n  ";
644   else
645     OS << "nullptr,\n  ";
646   OS << NumCostEntries << ", // Number of register cost entries.\n";
647 }
648 
649 unsigned
EmitRegisterFileTables(const CodeGenProcModel & ProcModel,raw_ostream & OS)650 SubtargetEmitter::EmitRegisterFileTables(const CodeGenProcModel &ProcModel,
651                                          raw_ostream &OS) {
652   if (llvm::all_of(ProcModel.RegisterFiles, [](const CodeGenRegisterFile &RF) {
653         return RF.hasDefaultCosts();
654       }))
655     return 0;
656 
657   // Print the RegisterCost table first.
658   OS << "\n// {RegisterClassID, Register Cost, AllowMoveElimination }\n";
659   OS << "static const llvm::MCRegisterCostEntry " << ProcModel.ModelName
660      << "RegisterCosts"
661      << "[] = {\n";
662 
663   for (const CodeGenRegisterFile &RF : ProcModel.RegisterFiles) {
664     // Skip register files with a default cost table.
665     if (RF.hasDefaultCosts())
666       continue;
667     // Add entries to the cost table.
668     for (const CodeGenRegisterCost &RC : RF.Costs) {
669       OS << "  { ";
670       Record *Rec = RC.RCDef;
671       if (Rec->getValue("Namespace"))
672         OS << Rec->getValueAsString("Namespace") << "::";
673       OS << Rec->getName() << "RegClassID, " << RC.Cost << ", "
674          << RC.AllowMoveElimination << "},\n";
675     }
676   }
677   OS << "};\n";
678 
679   // Now generate a table with register file info.
680   OS << "\n // {Name, #PhysRegs, #CostEntries, IndexToCostTbl, "
681      << "MaxMovesEliminatedPerCycle, AllowZeroMoveEliminationOnly }\n";
682   OS << "static const llvm::MCRegisterFileDesc " << ProcModel.ModelName
683      << "RegisterFiles"
684      << "[] = {\n"
685      << "  { \"InvalidRegisterFile\", 0, 0, 0, 0, 0 },\n";
686   unsigned CostTblIndex = 0;
687 
688   for (const CodeGenRegisterFile &RD : ProcModel.RegisterFiles) {
689     OS << "  { ";
690     OS << '"' << RD.Name << '"' << ", " << RD.NumPhysRegs << ", ";
691     unsigned NumCostEntries = RD.Costs.size();
692     OS << NumCostEntries << ", " << CostTblIndex << ", "
693        << RD.MaxMovesEliminatedPerCycle << ", "
694        << RD.AllowZeroMoveEliminationOnly << "},\n";
695     CostTblIndex += NumCostEntries;
696   }
697   OS << "};\n";
698 
699   return CostTblIndex;
700 }
701 
EmitLoadStoreQueueInfo(const CodeGenProcModel & ProcModel,raw_ostream & OS)702 void SubtargetEmitter::EmitLoadStoreQueueInfo(const CodeGenProcModel &ProcModel,
703                                               raw_ostream &OS) {
704   unsigned QueueID = 0;
705   if (ProcModel.LoadQueue) {
706     const Record *Queue = ProcModel.LoadQueue->getValueAsDef("QueueDescriptor");
707     QueueID =
708         1 + std::distance(ProcModel.ProcResourceDefs.begin(),
709                           std::find(ProcModel.ProcResourceDefs.begin(),
710                                     ProcModel.ProcResourceDefs.end(), Queue));
711   }
712   OS << "  " << QueueID << ", // Resource Descriptor for the Load Queue\n";
713 
714   QueueID = 0;
715   if (ProcModel.StoreQueue) {
716     const Record *Queue =
717         ProcModel.StoreQueue->getValueAsDef("QueueDescriptor");
718     QueueID =
719         1 + std::distance(ProcModel.ProcResourceDefs.begin(),
720                           std::find(ProcModel.ProcResourceDefs.begin(),
721                                     ProcModel.ProcResourceDefs.end(), Queue));
722   }
723   OS << "  " << QueueID << ", // Resource Descriptor for the Store Queue\n";
724 }
725 
EmitExtraProcessorInfo(const CodeGenProcModel & ProcModel,raw_ostream & OS)726 void SubtargetEmitter::EmitExtraProcessorInfo(const CodeGenProcModel &ProcModel,
727                                               raw_ostream &OS) {
728   // Generate a table of register file descriptors (one entry per each user
729   // defined register file), and a table of register costs.
730   unsigned NumCostEntries = EmitRegisterFileTables(ProcModel, OS);
731 
732   // Now generate a table for the extra processor info.
733   OS << "\nstatic const llvm::MCExtraProcessorInfo " << ProcModel.ModelName
734      << "ExtraInfo = {\n  ";
735 
736   // Add information related to the retire control unit.
737   EmitRetireControlUnitInfo(ProcModel, OS);
738 
739   // Add information related to the register files (i.e. where to find register
740   // file descriptors and register costs).
741   EmitRegisterFileInfo(ProcModel, ProcModel.RegisterFiles.size(),
742                        NumCostEntries, OS);
743 
744   // Add information about load/store queues.
745   EmitLoadStoreQueueInfo(ProcModel, OS);
746 
747   OS << "};\n";
748 }
749 
EmitProcessorResources(const CodeGenProcModel & ProcModel,raw_ostream & OS)750 void SubtargetEmitter::EmitProcessorResources(const CodeGenProcModel &ProcModel,
751                                               raw_ostream &OS) {
752   EmitProcessorResourceSubUnits(ProcModel, OS);
753 
754   OS << "\n// {Name, NumUnits, SuperIdx, BufferSize, SubUnitsIdxBegin}\n";
755   OS << "static const llvm::MCProcResourceDesc " << ProcModel.ModelName
756      << "ProcResources"
757      << "[] = {\n"
758      << "  {\"InvalidUnit\", 0, 0, 0, 0},\n";
759 
760   unsigned SubUnitsOffset = 1;
761   for (unsigned i = 0, e = ProcModel.ProcResourceDefs.size(); i < e; ++i) {
762     Record *PRDef = ProcModel.ProcResourceDefs[i];
763 
764     Record *SuperDef = nullptr;
765     unsigned SuperIdx = 0;
766     unsigned NumUnits = 0;
767     const unsigned SubUnitsBeginOffset = SubUnitsOffset;
768     int BufferSize = PRDef->getValueAsInt("BufferSize");
769     if (PRDef->isSubClassOf("ProcResGroup")) {
770       RecVec ResUnits = PRDef->getValueAsListOfDefs("Resources");
771       for (Record *RU : ResUnits) {
772         NumUnits += RU->getValueAsInt("NumUnits");
773         SubUnitsOffset += RU->getValueAsInt("NumUnits");
774       }
775     }
776     else {
777       // Find the SuperIdx
778       if (PRDef->getValueInit("Super")->isComplete()) {
779         SuperDef =
780             SchedModels.findProcResUnits(PRDef->getValueAsDef("Super"),
781                                          ProcModel, PRDef->getLoc());
782         SuperIdx = ProcModel.getProcResourceIdx(SuperDef);
783       }
784       NumUnits = PRDef->getValueAsInt("NumUnits");
785     }
786     // Emit the ProcResourceDesc
787     OS << "  {\"" << PRDef->getName() << "\", ";
788     if (PRDef->getName().size() < 15)
789       OS.indent(15 - PRDef->getName().size());
790     OS << NumUnits << ", " << SuperIdx << ", " << BufferSize << ", ";
791     if (SubUnitsBeginOffset != SubUnitsOffset) {
792       OS << ProcModel.ModelName << "ProcResourceSubUnits + "
793          << SubUnitsBeginOffset;
794     } else {
795       OS << "nullptr";
796     }
797     OS << "}, // #" << i+1;
798     if (SuperDef)
799       OS << ", Super=" << SuperDef->getName();
800     OS << "\n";
801   }
802   OS << "};\n";
803 }
804 
805 // Find the WriteRes Record that defines processor resources for this
806 // SchedWrite.
FindWriteResources(const CodeGenSchedRW & SchedWrite,const CodeGenProcModel & ProcModel)807 Record *SubtargetEmitter::FindWriteResources(
808   const CodeGenSchedRW &SchedWrite, const CodeGenProcModel &ProcModel) {
809 
810   // Check if the SchedWrite is already subtarget-specific and directly
811   // specifies a set of processor resources.
812   if (SchedWrite.TheDef->isSubClassOf("SchedWriteRes"))
813     return SchedWrite.TheDef;
814 
815   Record *AliasDef = nullptr;
816   for (Record *A : SchedWrite.Aliases) {
817     const CodeGenSchedRW &AliasRW =
818       SchedModels.getSchedRW(A->getValueAsDef("AliasRW"));
819     if (AliasRW.TheDef->getValueInit("SchedModel")->isComplete()) {
820       Record *ModelDef = AliasRW.TheDef->getValueAsDef("SchedModel");
821       if (&SchedModels.getProcModel(ModelDef) != &ProcModel)
822         continue;
823     }
824     if (AliasDef)
825       PrintFatalError(AliasRW.TheDef->getLoc(), "Multiple aliases "
826                     "defined for processor " + ProcModel.ModelName +
827                     " Ensure only one SchedAlias exists per RW.");
828     AliasDef = AliasRW.TheDef;
829   }
830   if (AliasDef && AliasDef->isSubClassOf("SchedWriteRes"))
831     return AliasDef;
832 
833   // Check this processor's list of write resources.
834   Record *ResDef = nullptr;
835   for (Record *WR : ProcModel.WriteResDefs) {
836     if (!WR->isSubClassOf("WriteRes"))
837       continue;
838     if (AliasDef == WR->getValueAsDef("WriteType")
839         || SchedWrite.TheDef == WR->getValueAsDef("WriteType")) {
840       if (ResDef) {
841         PrintFatalError(WR->getLoc(), "Resources are defined for both "
842                       "SchedWrite and its alias on processor " +
843                       ProcModel.ModelName);
844       }
845       ResDef = WR;
846     }
847   }
848   // TODO: If ProcModel has a base model (previous generation processor),
849   // then call FindWriteResources recursively with that model here.
850   if (!ResDef) {
851     PrintFatalError(ProcModel.ModelDef->getLoc(),
852                     Twine("Processor does not define resources for ") +
853                     SchedWrite.TheDef->getName());
854   }
855   return ResDef;
856 }
857 
858 /// Find the ReadAdvance record for the given SchedRead on this processor or
859 /// return NULL.
FindReadAdvance(const CodeGenSchedRW & SchedRead,const CodeGenProcModel & ProcModel)860 Record *SubtargetEmitter::FindReadAdvance(const CodeGenSchedRW &SchedRead,
861                                           const CodeGenProcModel &ProcModel) {
862   // Check for SchedReads that directly specify a ReadAdvance.
863   if (SchedRead.TheDef->isSubClassOf("SchedReadAdvance"))
864     return SchedRead.TheDef;
865 
866   // Check this processor's list of aliases for SchedRead.
867   Record *AliasDef = nullptr;
868   for (Record *A : SchedRead.Aliases) {
869     const CodeGenSchedRW &AliasRW =
870       SchedModels.getSchedRW(A->getValueAsDef("AliasRW"));
871     if (AliasRW.TheDef->getValueInit("SchedModel")->isComplete()) {
872       Record *ModelDef = AliasRW.TheDef->getValueAsDef("SchedModel");
873       if (&SchedModels.getProcModel(ModelDef) != &ProcModel)
874         continue;
875     }
876     if (AliasDef)
877       PrintFatalError(AliasRW.TheDef->getLoc(), "Multiple aliases "
878                     "defined for processor " + ProcModel.ModelName +
879                     " Ensure only one SchedAlias exists per RW.");
880     AliasDef = AliasRW.TheDef;
881   }
882   if (AliasDef && AliasDef->isSubClassOf("SchedReadAdvance"))
883     return AliasDef;
884 
885   // Check this processor's ReadAdvanceList.
886   Record *ResDef = nullptr;
887   for (Record *RA : ProcModel.ReadAdvanceDefs) {
888     if (!RA->isSubClassOf("ReadAdvance"))
889       continue;
890     if (AliasDef == RA->getValueAsDef("ReadType")
891         || SchedRead.TheDef == RA->getValueAsDef("ReadType")) {
892       if (ResDef) {
893         PrintFatalError(RA->getLoc(), "Resources are defined for both "
894                       "SchedRead and its alias on processor " +
895                       ProcModel.ModelName);
896       }
897       ResDef = RA;
898     }
899   }
900   // TODO: If ProcModel has a base model (previous generation processor),
901   // then call FindReadAdvance recursively with that model here.
902   if (!ResDef && SchedRead.TheDef->getName() != "ReadDefault") {
903     PrintFatalError(ProcModel.ModelDef->getLoc(),
904                     Twine("Processor does not define resources for ") +
905                     SchedRead.TheDef->getName());
906   }
907   return ResDef;
908 }
909 
910 // Expand an explicit list of processor resources into a full list of implied
911 // resource groups and super resources that cover them.
ExpandProcResources(RecVec & PRVec,std::vector<int64_t> & Cycles,const CodeGenProcModel & PM)912 void SubtargetEmitter::ExpandProcResources(RecVec &PRVec,
913                                            std::vector<int64_t> &Cycles,
914                                            const CodeGenProcModel &PM) {
915   assert(PRVec.size() == Cycles.size() && "failed precondition");
916   for (unsigned i = 0, e = PRVec.size(); i != e; ++i) {
917     Record *PRDef = PRVec[i];
918     RecVec SubResources;
919     if (PRDef->isSubClassOf("ProcResGroup"))
920       SubResources = PRDef->getValueAsListOfDefs("Resources");
921     else {
922       SubResources.push_back(PRDef);
923       PRDef = SchedModels.findProcResUnits(PRDef, PM, PRDef->getLoc());
924       for (Record *SubDef = PRDef;
925            SubDef->getValueInit("Super")->isComplete();) {
926         if (SubDef->isSubClassOf("ProcResGroup")) {
927           // Disallow this for simplicitly.
928           PrintFatalError(SubDef->getLoc(), "Processor resource group "
929                           " cannot be a super resources.");
930         }
931         Record *SuperDef =
932             SchedModels.findProcResUnits(SubDef->getValueAsDef("Super"), PM,
933                                          SubDef->getLoc());
934         PRVec.push_back(SuperDef);
935         Cycles.push_back(Cycles[i]);
936         SubDef = SuperDef;
937       }
938     }
939     for (Record *PR : PM.ProcResourceDefs) {
940       if (PR == PRDef || !PR->isSubClassOf("ProcResGroup"))
941         continue;
942       RecVec SuperResources = PR->getValueAsListOfDefs("Resources");
943       RecIter SubI = SubResources.begin(), SubE = SubResources.end();
944       for( ; SubI != SubE; ++SubI) {
945         if (!is_contained(SuperResources, *SubI)) {
946           break;
947         }
948       }
949       if (SubI == SubE) {
950         PRVec.push_back(PR);
951         Cycles.push_back(Cycles[i]);
952       }
953     }
954   }
955 }
956 
957 // Generate the SchedClass table for this processor and update global
958 // tables. Must be called for each processor in order.
GenSchedClassTables(const CodeGenProcModel & ProcModel,SchedClassTables & SchedTables)959 void SubtargetEmitter::GenSchedClassTables(const CodeGenProcModel &ProcModel,
960                                            SchedClassTables &SchedTables) {
961   SchedTables.ProcSchedClasses.resize(SchedTables.ProcSchedClasses.size() + 1);
962   if (!ProcModel.hasInstrSchedModel())
963     return;
964 
965   std::vector<MCSchedClassDesc> &SCTab = SchedTables.ProcSchedClasses.back();
966   LLVM_DEBUG(dbgs() << "\n+++ SCHED CLASSES (GenSchedClassTables) +++\n");
967   for (const CodeGenSchedClass &SC : SchedModels.schedClasses()) {
968     LLVM_DEBUG(SC.dump(&SchedModels));
969 
970     SCTab.resize(SCTab.size() + 1);
971     MCSchedClassDesc &SCDesc = SCTab.back();
972     // SCDesc.Name is guarded by NDEBUG
973     SCDesc.NumMicroOps = 0;
974     SCDesc.BeginGroup = false;
975     SCDesc.EndGroup = false;
976     SCDesc.WriteProcResIdx = 0;
977     SCDesc.WriteLatencyIdx = 0;
978     SCDesc.ReadAdvanceIdx = 0;
979 
980     // A Variant SchedClass has no resources of its own.
981     bool HasVariants = false;
982     for (const CodeGenSchedTransition &CGT :
983            make_range(SC.Transitions.begin(), SC.Transitions.end())) {
984       if (CGT.ProcIndices[0] == 0 ||
985           is_contained(CGT.ProcIndices, ProcModel.Index)) {
986         HasVariants = true;
987         break;
988       }
989     }
990     if (HasVariants) {
991       SCDesc.NumMicroOps = MCSchedClassDesc::VariantNumMicroOps;
992       continue;
993     }
994 
995     // Determine if the SchedClass is actually reachable on this processor. If
996     // not don't try to locate the processor resources, it will fail.
997     // If ProcIndices contains 0, this class applies to all processors.
998     assert(!SC.ProcIndices.empty() && "expect at least one procidx");
999     if (SC.ProcIndices[0] != 0) {
1000       if (!is_contained(SC.ProcIndices, ProcModel.Index))
1001         continue;
1002     }
1003     IdxVec Writes = SC.Writes;
1004     IdxVec Reads = SC.Reads;
1005     if (!SC.InstRWs.empty()) {
1006       // This class has a default ReadWrite list which can be overridden by
1007       // InstRW definitions.
1008       Record *RWDef = nullptr;
1009       for (Record *RW : SC.InstRWs) {
1010         Record *RWModelDef = RW->getValueAsDef("SchedModel");
1011         if (&ProcModel == &SchedModels.getProcModel(RWModelDef)) {
1012           RWDef = RW;
1013           break;
1014         }
1015       }
1016       if (RWDef) {
1017         Writes.clear();
1018         Reads.clear();
1019         SchedModels.findRWs(RWDef->getValueAsListOfDefs("OperandReadWrites"),
1020                             Writes, Reads);
1021       }
1022     }
1023     if (Writes.empty()) {
1024       // Check this processor's itinerary class resources.
1025       for (Record *I : ProcModel.ItinRWDefs) {
1026         RecVec Matched = I->getValueAsListOfDefs("MatchedItinClasses");
1027         if (is_contained(Matched, SC.ItinClassDef)) {
1028           SchedModels.findRWs(I->getValueAsListOfDefs("OperandReadWrites"),
1029                               Writes, Reads);
1030           break;
1031         }
1032       }
1033       if (Writes.empty()) {
1034         LLVM_DEBUG(dbgs() << ProcModel.ModelName
1035                           << " does not have resources for class " << SC.Name
1036                           << '\n');
1037       }
1038     }
1039     // Sum resources across all operand writes.
1040     std::vector<MCWriteProcResEntry> WriteProcResources;
1041     std::vector<MCWriteLatencyEntry> WriteLatencies;
1042     std::vector<std::string> WriterNames;
1043     std::vector<MCReadAdvanceEntry> ReadAdvanceEntries;
1044     for (unsigned W : Writes) {
1045       IdxVec WriteSeq;
1046       SchedModels.expandRWSeqForProc(W, WriteSeq, /*IsRead=*/false,
1047                                      ProcModel);
1048 
1049       // For each operand, create a latency entry.
1050       MCWriteLatencyEntry WLEntry;
1051       WLEntry.Cycles = 0;
1052       unsigned WriteID = WriteSeq.back();
1053       WriterNames.push_back(SchedModels.getSchedWrite(WriteID).Name);
1054       // If this Write is not referenced by a ReadAdvance, don't distinguish it
1055       // from other WriteLatency entries.
1056       if (!SchedModels.hasReadOfWrite(
1057             SchedModels.getSchedWrite(WriteID).TheDef)) {
1058         WriteID = 0;
1059       }
1060       WLEntry.WriteResourceID = WriteID;
1061 
1062       for (unsigned WS : WriteSeq) {
1063 
1064         Record *WriteRes =
1065           FindWriteResources(SchedModels.getSchedWrite(WS), ProcModel);
1066 
1067         // Mark the parent class as invalid for unsupported write types.
1068         if (WriteRes->getValueAsBit("Unsupported")) {
1069           SCDesc.NumMicroOps = MCSchedClassDesc::InvalidNumMicroOps;
1070           break;
1071         }
1072         WLEntry.Cycles += WriteRes->getValueAsInt("Latency");
1073         SCDesc.NumMicroOps += WriteRes->getValueAsInt("NumMicroOps");
1074         SCDesc.BeginGroup |= WriteRes->getValueAsBit("BeginGroup");
1075         SCDesc.EndGroup |= WriteRes->getValueAsBit("EndGroup");
1076         SCDesc.BeginGroup |= WriteRes->getValueAsBit("SingleIssue");
1077         SCDesc.EndGroup |= WriteRes->getValueAsBit("SingleIssue");
1078 
1079         // Create an entry for each ProcResource listed in WriteRes.
1080         RecVec PRVec = WriteRes->getValueAsListOfDefs("ProcResources");
1081         std::vector<int64_t> Cycles =
1082           WriteRes->getValueAsListOfInts("ResourceCycles");
1083 
1084         if (Cycles.empty()) {
1085           // If ResourceCycles is not provided, default to one cycle per
1086           // resource.
1087           Cycles.resize(PRVec.size(), 1);
1088         } else if (Cycles.size() != PRVec.size()) {
1089           // If ResourceCycles is provided, check consistency.
1090           PrintFatalError(
1091               WriteRes->getLoc(),
1092               Twine("Inconsistent resource cycles: !size(ResourceCycles) != "
1093                     "!size(ProcResources): ")
1094                   .concat(Twine(PRVec.size()))
1095                   .concat(" vs ")
1096                   .concat(Twine(Cycles.size())));
1097         }
1098 
1099         ExpandProcResources(PRVec, Cycles, ProcModel);
1100 
1101         for (unsigned PRIdx = 0, PREnd = PRVec.size();
1102              PRIdx != PREnd; ++PRIdx) {
1103           MCWriteProcResEntry WPREntry;
1104           WPREntry.ProcResourceIdx = ProcModel.getProcResourceIdx(PRVec[PRIdx]);
1105           assert(WPREntry.ProcResourceIdx && "Bad ProcResourceIdx");
1106           WPREntry.Cycles = Cycles[PRIdx];
1107           // If this resource is already used in this sequence, add the current
1108           // entry's cycles so that the same resource appears to be used
1109           // serially, rather than multiple parallel uses. This is important for
1110           // in-order machine where the resource consumption is a hazard.
1111           unsigned WPRIdx = 0, WPREnd = WriteProcResources.size();
1112           for( ; WPRIdx != WPREnd; ++WPRIdx) {
1113             if (WriteProcResources[WPRIdx].ProcResourceIdx
1114                 == WPREntry.ProcResourceIdx) {
1115               WriteProcResources[WPRIdx].Cycles += WPREntry.Cycles;
1116               break;
1117             }
1118           }
1119           if (WPRIdx == WPREnd)
1120             WriteProcResources.push_back(WPREntry);
1121         }
1122       }
1123       WriteLatencies.push_back(WLEntry);
1124     }
1125     // Create an entry for each operand Read in this SchedClass.
1126     // Entries must be sorted first by UseIdx then by WriteResourceID.
1127     for (unsigned UseIdx = 0, EndIdx = Reads.size();
1128          UseIdx != EndIdx; ++UseIdx) {
1129       Record *ReadAdvance =
1130         FindReadAdvance(SchedModels.getSchedRead(Reads[UseIdx]), ProcModel);
1131       if (!ReadAdvance)
1132         continue;
1133 
1134       // Mark the parent class as invalid for unsupported write types.
1135       if (ReadAdvance->getValueAsBit("Unsupported")) {
1136         SCDesc.NumMicroOps = MCSchedClassDesc::InvalidNumMicroOps;
1137         break;
1138       }
1139       RecVec ValidWrites = ReadAdvance->getValueAsListOfDefs("ValidWrites");
1140       IdxVec WriteIDs;
1141       if (ValidWrites.empty())
1142         WriteIDs.push_back(0);
1143       else {
1144         for (Record *VW : ValidWrites) {
1145           WriteIDs.push_back(SchedModels.getSchedRWIdx(VW, /*IsRead=*/false));
1146         }
1147       }
1148       llvm::sort(WriteIDs);
1149       for(unsigned W : WriteIDs) {
1150         MCReadAdvanceEntry RAEntry;
1151         RAEntry.UseIdx = UseIdx;
1152         RAEntry.WriteResourceID = W;
1153         RAEntry.Cycles = ReadAdvance->getValueAsInt("Cycles");
1154         ReadAdvanceEntries.push_back(RAEntry);
1155       }
1156     }
1157     if (SCDesc.NumMicroOps == MCSchedClassDesc::InvalidNumMicroOps) {
1158       WriteProcResources.clear();
1159       WriteLatencies.clear();
1160       ReadAdvanceEntries.clear();
1161     }
1162     // Add the information for this SchedClass to the global tables using basic
1163     // compression.
1164     //
1165     // WritePrecRes entries are sorted by ProcResIdx.
1166     llvm::sort(WriteProcResources, LessWriteProcResources());
1167 
1168     SCDesc.NumWriteProcResEntries = WriteProcResources.size();
1169     std::vector<MCWriteProcResEntry>::iterator WPRPos =
1170       std::search(SchedTables.WriteProcResources.begin(),
1171                   SchedTables.WriteProcResources.end(),
1172                   WriteProcResources.begin(), WriteProcResources.end());
1173     if (WPRPos != SchedTables.WriteProcResources.end())
1174       SCDesc.WriteProcResIdx = WPRPos - SchedTables.WriteProcResources.begin();
1175     else {
1176       SCDesc.WriteProcResIdx = SchedTables.WriteProcResources.size();
1177       SchedTables.WriteProcResources.insert(WPRPos, WriteProcResources.begin(),
1178                                             WriteProcResources.end());
1179     }
1180     // Latency entries must remain in operand order.
1181     SCDesc.NumWriteLatencyEntries = WriteLatencies.size();
1182     std::vector<MCWriteLatencyEntry>::iterator WLPos =
1183       std::search(SchedTables.WriteLatencies.begin(),
1184                   SchedTables.WriteLatencies.end(),
1185                   WriteLatencies.begin(), WriteLatencies.end());
1186     if (WLPos != SchedTables.WriteLatencies.end()) {
1187       unsigned idx = WLPos - SchedTables.WriteLatencies.begin();
1188       SCDesc.WriteLatencyIdx = idx;
1189       for (unsigned i = 0, e = WriteLatencies.size(); i < e; ++i)
1190         if (SchedTables.WriterNames[idx + i].find(WriterNames[i]) ==
1191             std::string::npos) {
1192           SchedTables.WriterNames[idx + i] += std::string("_") + WriterNames[i];
1193         }
1194     }
1195     else {
1196       SCDesc.WriteLatencyIdx = SchedTables.WriteLatencies.size();
1197       SchedTables.WriteLatencies.insert(SchedTables.WriteLatencies.end(),
1198                                         WriteLatencies.begin(),
1199                                         WriteLatencies.end());
1200       SchedTables.WriterNames.insert(SchedTables.WriterNames.end(),
1201                                      WriterNames.begin(), WriterNames.end());
1202     }
1203     // ReadAdvanceEntries must remain in operand order.
1204     SCDesc.NumReadAdvanceEntries = ReadAdvanceEntries.size();
1205     std::vector<MCReadAdvanceEntry>::iterator RAPos =
1206       std::search(SchedTables.ReadAdvanceEntries.begin(),
1207                   SchedTables.ReadAdvanceEntries.end(),
1208                   ReadAdvanceEntries.begin(), ReadAdvanceEntries.end());
1209     if (RAPos != SchedTables.ReadAdvanceEntries.end())
1210       SCDesc.ReadAdvanceIdx = RAPos - SchedTables.ReadAdvanceEntries.begin();
1211     else {
1212       SCDesc.ReadAdvanceIdx = SchedTables.ReadAdvanceEntries.size();
1213       SchedTables.ReadAdvanceEntries.insert(RAPos, ReadAdvanceEntries.begin(),
1214                                             ReadAdvanceEntries.end());
1215     }
1216   }
1217 }
1218 
1219 // Emit SchedClass tables for all processors and associated global tables.
EmitSchedClassTables(SchedClassTables & SchedTables,raw_ostream & OS)1220 void SubtargetEmitter::EmitSchedClassTables(SchedClassTables &SchedTables,
1221                                             raw_ostream &OS) {
1222   // Emit global WriteProcResTable.
1223   OS << "\n// {ProcResourceIdx, Cycles}\n"
1224      << "extern const llvm::MCWriteProcResEntry "
1225      << Target << "WriteProcResTable[] = {\n"
1226      << "  { 0,  0}, // Invalid\n";
1227   for (unsigned WPRIdx = 1, WPREnd = SchedTables.WriteProcResources.size();
1228        WPRIdx != WPREnd; ++WPRIdx) {
1229     MCWriteProcResEntry &WPREntry = SchedTables.WriteProcResources[WPRIdx];
1230     OS << "  {" << format("%2d", WPREntry.ProcResourceIdx) << ", "
1231        << format("%2d", WPREntry.Cycles) << "}";
1232     if (WPRIdx + 1 < WPREnd)
1233       OS << ',';
1234     OS << " // #" << WPRIdx << '\n';
1235   }
1236   OS << "}; // " << Target << "WriteProcResTable\n";
1237 
1238   // Emit global WriteLatencyTable.
1239   OS << "\n// {Cycles, WriteResourceID}\n"
1240      << "extern const llvm::MCWriteLatencyEntry "
1241      << Target << "WriteLatencyTable[] = {\n"
1242      << "  { 0,  0}, // Invalid\n";
1243   for (unsigned WLIdx = 1, WLEnd = SchedTables.WriteLatencies.size();
1244        WLIdx != WLEnd; ++WLIdx) {
1245     MCWriteLatencyEntry &WLEntry = SchedTables.WriteLatencies[WLIdx];
1246     OS << "  {" << format("%2d", WLEntry.Cycles) << ", "
1247        << format("%2d", WLEntry.WriteResourceID) << "}";
1248     if (WLIdx + 1 < WLEnd)
1249       OS << ',';
1250     OS << " // #" << WLIdx << " " << SchedTables.WriterNames[WLIdx] << '\n';
1251   }
1252   OS << "}; // " << Target << "WriteLatencyTable\n";
1253 
1254   // Emit global ReadAdvanceTable.
1255   OS << "\n// {UseIdx, WriteResourceID, Cycles}\n"
1256      << "extern const llvm::MCReadAdvanceEntry "
1257      << Target << "ReadAdvanceTable[] = {\n"
1258      << "  {0,  0,  0}, // Invalid\n";
1259   for (unsigned RAIdx = 1, RAEnd = SchedTables.ReadAdvanceEntries.size();
1260        RAIdx != RAEnd; ++RAIdx) {
1261     MCReadAdvanceEntry &RAEntry = SchedTables.ReadAdvanceEntries[RAIdx];
1262     OS << "  {" << RAEntry.UseIdx << ", "
1263        << format("%2d", RAEntry.WriteResourceID) << ", "
1264        << format("%2d", RAEntry.Cycles) << "}";
1265     if (RAIdx + 1 < RAEnd)
1266       OS << ',';
1267     OS << " // #" << RAIdx << '\n';
1268   }
1269   OS << "}; // " << Target << "ReadAdvanceTable\n";
1270 
1271   // Emit a SchedClass table for each processor.
1272   for (CodeGenSchedModels::ProcIter PI = SchedModels.procModelBegin(),
1273          PE = SchedModels.procModelEnd(); PI != PE; ++PI) {
1274     if (!PI->hasInstrSchedModel())
1275       continue;
1276 
1277     std::vector<MCSchedClassDesc> &SCTab =
1278       SchedTables.ProcSchedClasses[1 + (PI - SchedModels.procModelBegin())];
1279 
1280     OS << "\n// {Name, NumMicroOps, BeginGroup, EndGroup,"
1281        << " WriteProcResIdx,#, WriteLatencyIdx,#, ReadAdvanceIdx,#}\n";
1282     OS << "static const llvm::MCSchedClassDesc "
1283        << PI->ModelName << "SchedClasses[] = {\n";
1284 
1285     // The first class is always invalid. We no way to distinguish it except by
1286     // name and position.
1287     assert(SchedModels.getSchedClass(0).Name == "NoInstrModel"
1288            && "invalid class not first");
1289     OS << "  {DBGFIELD(\"InvalidSchedClass\")  "
1290        << MCSchedClassDesc::InvalidNumMicroOps
1291        << ", false, false,  0, 0,  0, 0,  0, 0},\n";
1292 
1293     for (unsigned SCIdx = 1, SCEnd = SCTab.size(); SCIdx != SCEnd; ++SCIdx) {
1294       MCSchedClassDesc &MCDesc = SCTab[SCIdx];
1295       const CodeGenSchedClass &SchedClass = SchedModels.getSchedClass(SCIdx);
1296       OS << "  {DBGFIELD(\"" << SchedClass.Name << "\") ";
1297       if (SchedClass.Name.size() < 18)
1298         OS.indent(18 - SchedClass.Name.size());
1299       OS << MCDesc.NumMicroOps
1300          << ", " << ( MCDesc.BeginGroup ? "true" : "false" )
1301          << ", " << ( MCDesc.EndGroup ? "true" : "false" )
1302          << ", " << format("%2d", MCDesc.WriteProcResIdx)
1303          << ", " << MCDesc.NumWriteProcResEntries
1304          << ", " << format("%2d", MCDesc.WriteLatencyIdx)
1305          << ", " << MCDesc.NumWriteLatencyEntries
1306          << ", " << format("%2d", MCDesc.ReadAdvanceIdx)
1307          << ", " << MCDesc.NumReadAdvanceEntries
1308          << "}, // #" << SCIdx << '\n';
1309     }
1310     OS << "}; // " << PI->ModelName << "SchedClasses\n";
1311   }
1312 }
1313 
EmitProcessorModels(raw_ostream & OS)1314 void SubtargetEmitter::EmitProcessorModels(raw_ostream &OS) {
1315   // For each processor model.
1316   for (const CodeGenProcModel &PM : SchedModels.procModels()) {
1317     // Emit extra processor info if available.
1318     if (PM.hasExtraProcessorInfo())
1319       EmitExtraProcessorInfo(PM, OS);
1320     // Emit processor resource table.
1321     if (PM.hasInstrSchedModel())
1322       EmitProcessorResources(PM, OS);
1323     else if(!PM.ProcResourceDefs.empty())
1324       PrintFatalError(PM.ModelDef->getLoc(), "SchedMachineModel defines "
1325                     "ProcResources without defining WriteRes SchedWriteRes");
1326 
1327     // Begin processor itinerary properties
1328     OS << "\n";
1329     OS << "static const llvm::MCSchedModel " << PM.ModelName << " = {\n";
1330     EmitProcessorProp(OS, PM.ModelDef, "IssueWidth", ',');
1331     EmitProcessorProp(OS, PM.ModelDef, "MicroOpBufferSize", ',');
1332     EmitProcessorProp(OS, PM.ModelDef, "LoopMicroOpBufferSize", ',');
1333     EmitProcessorProp(OS, PM.ModelDef, "LoadLatency", ',');
1334     EmitProcessorProp(OS, PM.ModelDef, "HighLatency", ',');
1335     EmitProcessorProp(OS, PM.ModelDef, "MispredictPenalty", ',');
1336 
1337     bool PostRAScheduler =
1338       (PM.ModelDef ? PM.ModelDef->getValueAsBit("PostRAScheduler") : false);
1339 
1340     OS << "  " << (PostRAScheduler ? "true" : "false")  << ", // "
1341        << "PostRAScheduler\n";
1342 
1343     bool CompleteModel =
1344       (PM.ModelDef ? PM.ModelDef->getValueAsBit("CompleteModel") : false);
1345 
1346     OS << "  " << (CompleteModel ? "true" : "false") << ", // "
1347        << "CompleteModel\n";
1348 
1349     OS << "  " << PM.Index << ", // Processor ID\n";
1350     if (PM.hasInstrSchedModel())
1351       OS << "  " << PM.ModelName << "ProcResources" << ",\n"
1352          << "  " << PM.ModelName << "SchedClasses" << ",\n"
1353          << "  " << PM.ProcResourceDefs.size()+1 << ",\n"
1354          << "  " << (SchedModels.schedClassEnd()
1355                      - SchedModels.schedClassBegin()) << ",\n";
1356     else
1357       OS << "  nullptr, nullptr, 0, 0,"
1358          << " // No instruction-level machine model.\n";
1359     if (PM.hasItineraries())
1360       OS << "  " << PM.ItinsDef->getName() << ",\n";
1361     else
1362       OS << "  nullptr, // No Itinerary\n";
1363     if (PM.hasExtraProcessorInfo())
1364       OS << "  &" << PM.ModelName << "ExtraInfo,\n";
1365     else
1366       OS << "  nullptr // No extra processor descriptor\n";
1367     OS << "};\n";
1368   }
1369 }
1370 
1371 //
1372 // EmitProcessorLookup - generate cpu name to sched model lookup tables.
1373 //
EmitProcessorLookup(raw_ostream & OS)1374 void SubtargetEmitter::EmitProcessorLookup(raw_ostream &OS) {
1375   // Gather and sort processor information
1376   std::vector<Record*> ProcessorList =
1377                           Records.getAllDerivedDefinitions("Processor");
1378   llvm::sort(ProcessorList, LessRecordFieldName());
1379 
1380   // Begin processor->sched model table
1381   OS << "\n";
1382   OS << "// Sorted (by key) array of sched model for CPU subtype.\n"
1383      << "extern const llvm::SubtargetInfoKV " << Target
1384      << "ProcSchedKV[] = {\n";
1385   // For each processor
1386   for (Record *Processor : ProcessorList) {
1387     StringRef Name = Processor->getValueAsString("Name");
1388     const std::string &ProcModelName =
1389       SchedModels.getModelForProc(Processor).ModelName;
1390 
1391     // Emit as { "cpu", procinit },
1392     OS << "  { \"" << Name << "\", (const void *)&" << ProcModelName << " },\n";
1393   }
1394   // End processor->sched model table
1395   OS << "};\n";
1396 }
1397 
1398 //
1399 // EmitSchedModel - Emits all scheduling model tables, folding common patterns.
1400 //
EmitSchedModel(raw_ostream & OS)1401 void SubtargetEmitter::EmitSchedModel(raw_ostream &OS) {
1402   OS << "#ifdef DBGFIELD\n"
1403      << "#error \"<target>GenSubtargetInfo.inc requires a DBGFIELD macro\"\n"
1404      << "#endif\n"
1405      << "#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)\n"
1406      << "#define DBGFIELD(x) x,\n"
1407      << "#else\n"
1408      << "#define DBGFIELD(x)\n"
1409      << "#endif\n";
1410 
1411   if (SchedModels.hasItineraries()) {
1412     std::vector<std::vector<InstrItinerary>> ProcItinLists;
1413     // Emit the stage data
1414     EmitStageAndOperandCycleData(OS, ProcItinLists);
1415     EmitItineraries(OS, ProcItinLists);
1416   }
1417   OS << "\n// ===============================================================\n"
1418      << "// Data tables for the new per-operand machine model.\n";
1419 
1420   SchedClassTables SchedTables;
1421   for (const CodeGenProcModel &ProcModel : SchedModels.procModels()) {
1422     GenSchedClassTables(ProcModel, SchedTables);
1423   }
1424   EmitSchedClassTables(SchedTables, OS);
1425 
1426   // Emit the processor machine model
1427   EmitProcessorModels(OS);
1428   // Emit the processor lookup data
1429   EmitProcessorLookup(OS);
1430 
1431   OS << "\n#undef DBGFIELD";
1432 }
1433 
emitPredicateProlog(const RecordKeeper & Records,raw_ostream & OS)1434 static void emitPredicateProlog(const RecordKeeper &Records, raw_ostream &OS) {
1435   std::string Buffer;
1436   raw_string_ostream Stream(Buffer);
1437 
1438   // Collect all the PredicateProlog records and print them to the output
1439   // stream.
1440   std::vector<Record *> Prologs =
1441       Records.getAllDerivedDefinitions("PredicateProlog");
1442   llvm::sort(Prologs, LessRecord());
1443   for (Record *P : Prologs)
1444     Stream << P->getValueAsString("Code") << '\n';
1445 
1446   Stream.flush();
1447   OS << Buffer;
1448 }
1449 
emitPredicates(const CodeGenSchedTransition & T,const CodeGenSchedClass & SC,PredicateExpander & PE,raw_ostream & OS)1450 static void emitPredicates(const CodeGenSchedTransition &T,
1451                            const CodeGenSchedClass &SC, PredicateExpander &PE,
1452                            raw_ostream &OS) {
1453   std::string Buffer;
1454   raw_string_ostream SS(Buffer);
1455 
1456   auto IsTruePredicate = [](const Record *Rec) {
1457     return Rec->isSubClassOf("MCSchedPredicate") &&
1458            Rec->getValueAsDef("Pred")->isSubClassOf("MCTrue");
1459   };
1460 
1461   // If not all predicates are MCTrue, then we need an if-stmt.
1462   unsigned NumNonTruePreds =
1463       T.PredTerm.size() - count_if(T.PredTerm, IsTruePredicate);
1464 
1465   SS.indent(PE.getIndentLevel() * 2);
1466 
1467   if (NumNonTruePreds) {
1468     bool FirstNonTruePredicate = true;
1469     SS << "if (";
1470 
1471     PE.setIndentLevel(PE.getIndentLevel() + 2);
1472 
1473     for (const Record *Rec : T.PredTerm) {
1474       // Skip predicates that evaluate to "true".
1475       if (IsTruePredicate(Rec))
1476         continue;
1477 
1478       if (FirstNonTruePredicate) {
1479         FirstNonTruePredicate = false;
1480       } else {
1481         SS << "\n";
1482         SS.indent(PE.getIndentLevel() * 2);
1483         SS << "&& ";
1484       }
1485 
1486       if (Rec->isSubClassOf("MCSchedPredicate")) {
1487         PE.expandPredicate(SS, Rec->getValueAsDef("Pred"));
1488         continue;
1489       }
1490 
1491       // Expand this legacy predicate and wrap it around braces if there is more
1492       // than one predicate to expand.
1493       SS << ((NumNonTruePreds > 1) ? "(" : "")
1494          << Rec->getValueAsString("Predicate")
1495          << ((NumNonTruePreds > 1) ? ")" : "");
1496     }
1497 
1498     SS << ")\n"; // end of if-stmt
1499     PE.decreaseIndentLevel();
1500     SS.indent(PE.getIndentLevel() * 2);
1501     PE.decreaseIndentLevel();
1502   }
1503 
1504   SS << "return " << T.ToClassIdx << "; // " << SC.Name << '\n';
1505   SS.flush();
1506   OS << Buffer;
1507 }
1508 
1509 // Used by method `SubtargetEmitter::emitSchedModelHelpersImpl()` to generate
1510 // epilogue code for the auto-generated helper.
emitSchedModelHelperEpilogue(raw_ostream & OS,bool ShouldReturnZero)1511 void emitSchedModelHelperEpilogue(raw_ostream &OS, bool ShouldReturnZero) {
1512   if (ShouldReturnZero) {
1513     OS << "  // Don't know how to resolve this scheduling class.\n"
1514        << "  return 0;\n";
1515     return;
1516   }
1517 
1518   OS << "  report_fatal_error(\"Expected a variant SchedClass\");\n";
1519 }
1520 
hasMCSchedPredicates(const CodeGenSchedTransition & T)1521 bool hasMCSchedPredicates(const CodeGenSchedTransition &T) {
1522   return all_of(T.PredTerm, [](const Record *Rec) {
1523     return Rec->isSubClassOf("MCSchedPredicate");
1524   });
1525 }
1526 
collectVariantClasses(const CodeGenSchedModels & SchedModels,IdxVec & VariantClasses,bool OnlyExpandMCInstPredicates)1527 void collectVariantClasses(const CodeGenSchedModels &SchedModels,
1528                            IdxVec &VariantClasses,
1529                            bool OnlyExpandMCInstPredicates) {
1530   for (const CodeGenSchedClass &SC : SchedModels.schedClasses()) {
1531     // Ignore non-variant scheduling classes.
1532     if (SC.Transitions.empty())
1533       continue;
1534 
1535     if (OnlyExpandMCInstPredicates) {
1536       // Ignore this variant scheduling class no transitions use any meaningful
1537       // MCSchedPredicate definitions.
1538       if (!any_of(SC.Transitions, [](const CodeGenSchedTransition &T) {
1539             return hasMCSchedPredicates(T);
1540           }))
1541         continue;
1542     }
1543 
1544     VariantClasses.push_back(SC.Index);
1545   }
1546 }
1547 
collectProcessorIndices(const CodeGenSchedClass & SC,IdxVec & ProcIndices)1548 void collectProcessorIndices(const CodeGenSchedClass &SC, IdxVec &ProcIndices) {
1549   // A variant scheduling class may define transitions for multiple
1550   // processors.  This function identifies wich processors are associated with
1551   // transition rules specified by variant class `SC`.
1552   for (const CodeGenSchedTransition &T : SC.Transitions) {
1553     IdxVec PI;
1554     std::set_union(T.ProcIndices.begin(), T.ProcIndices.end(),
1555                    ProcIndices.begin(), ProcIndices.end(),
1556                    std::back_inserter(PI));
1557     ProcIndices.swap(PI);
1558   }
1559 }
1560 
emitSchedModelHelpersImpl(raw_ostream & OS,bool OnlyExpandMCInstPredicates)1561 void SubtargetEmitter::emitSchedModelHelpersImpl(
1562     raw_ostream &OS, bool OnlyExpandMCInstPredicates) {
1563   IdxVec VariantClasses;
1564   collectVariantClasses(SchedModels, VariantClasses,
1565                         OnlyExpandMCInstPredicates);
1566 
1567   if (VariantClasses.empty()) {
1568     emitSchedModelHelperEpilogue(OS, OnlyExpandMCInstPredicates);
1569     return;
1570   }
1571 
1572   // Construct a switch statement where the condition is a check on the
1573   // scheduling class identifier. There is a `case` for every variant class
1574   // defined by the processor models of this target.
1575   // Each `case` implements a number of rules to resolve (i.e. to transition from)
1576   // a variant scheduling class to another scheduling class.  Rules are
1577   // described by instances of CodeGenSchedTransition. Note that transitions may
1578   // not be valid for all processors.
1579   OS << "  switch (SchedClass) {\n";
1580   for (unsigned VC : VariantClasses) {
1581     IdxVec ProcIndices;
1582     const CodeGenSchedClass &SC = SchedModels.getSchedClass(VC);
1583     collectProcessorIndices(SC, ProcIndices);
1584 
1585     OS << "  case " << VC << ": // " << SC.Name << '\n';
1586 
1587     PredicateExpander PE(Target);
1588     PE.setByRef(false);
1589     PE.setExpandForMC(OnlyExpandMCInstPredicates);
1590     for (unsigned PI : ProcIndices) {
1591       OS << "    ";
1592 
1593       // Emit a guard on the processor ID.
1594       if (PI != 0) {
1595         OS << (OnlyExpandMCInstPredicates
1596                    ? "if (CPUID == "
1597                    : "if (SchedModel->getProcessorID() == ");
1598         OS << PI << ") ";
1599         OS << "{ // " << (SchedModels.procModelBegin() + PI)->ModelName << '\n';
1600       }
1601 
1602       // Now emit transitions associated with processor PI.
1603       for (const CodeGenSchedTransition &T : SC.Transitions) {
1604         if (PI != 0 && !count(T.ProcIndices, PI))
1605           continue;
1606 
1607         // Emit only transitions based on MCSchedPredicate, if it's the case.
1608         // At least the transition specified by NoSchedPred is emitted,
1609         // which becomes the default transition for those variants otherwise
1610         // not based on MCSchedPredicate.
1611         // FIXME: preferably, llvm-mca should instead assume a reasonable
1612         // default when a variant transition is not based on MCSchedPredicate
1613         // for a given processor.
1614         if (OnlyExpandMCInstPredicates && !hasMCSchedPredicates(T))
1615           continue;
1616 
1617         PE.setIndentLevel(3);
1618         emitPredicates(T, SchedModels.getSchedClass(T.ToClassIdx), PE, OS);
1619       }
1620 
1621       OS << "    }\n";
1622 
1623       if (PI == 0)
1624         break;
1625     }
1626 
1627     if (SC.isInferred())
1628       OS << "    return " << SC.Index << ";\n";
1629     OS << "    break;\n";
1630   }
1631 
1632   OS << "  };\n";
1633 
1634   emitSchedModelHelperEpilogue(OS, OnlyExpandMCInstPredicates);
1635 }
1636 
EmitSchedModelHelpers(const std::string & ClassName,raw_ostream & OS)1637 void SubtargetEmitter::EmitSchedModelHelpers(const std::string &ClassName,
1638                                              raw_ostream &OS) {
1639   OS << "unsigned " << ClassName
1640      << "\n::resolveSchedClass(unsigned SchedClass, const MachineInstr *MI,"
1641      << " const TargetSchedModel *SchedModel) const {\n";
1642 
1643   // Emit the predicate prolog code.
1644   emitPredicateProlog(Records, OS);
1645 
1646   // Emit target predicates.
1647   emitSchedModelHelpersImpl(OS);
1648 
1649   OS << "} // " << ClassName << "::resolveSchedClass\n\n";
1650 
1651   OS << "unsigned " << ClassName
1652      << "\n::resolveVariantSchedClass(unsigned SchedClass, const MCInst *MI,"
1653      << " unsigned CPUID) const {\n"
1654      << "  return " << Target << "_MC"
1655      << "::resolveVariantSchedClassImpl(SchedClass, MI, CPUID);\n"
1656      << "} // " << ClassName << "::resolveVariantSchedClass\n\n";
1657 
1658   STIPredicateExpander PE(Target);
1659   PE.setClassPrefix(ClassName);
1660   PE.setExpandDefinition(true);
1661   PE.setByRef(false);
1662   PE.setIndentLevel(0);
1663 
1664   for (const STIPredicateFunction &Fn : SchedModels.getSTIPredicates())
1665     PE.expandSTIPredicate(OS, Fn);
1666 }
1667 
EmitHwModeCheck(const std::string & ClassName,raw_ostream & OS)1668 void SubtargetEmitter::EmitHwModeCheck(const std::string &ClassName,
1669                                        raw_ostream &OS) {
1670   const CodeGenHwModes &CGH = TGT.getHwModes();
1671   assert(CGH.getNumModeIds() > 0);
1672   if (CGH.getNumModeIds() == 1)
1673     return;
1674 
1675   OS << "unsigned " << ClassName << "::getHwMode() const {\n";
1676   for (unsigned M = 1, NumModes = CGH.getNumModeIds(); M != NumModes; ++M) {
1677     const HwMode &HM = CGH.getMode(M);
1678     OS << "  if (checkFeatures(\"" << HM.Features
1679        << "\")) return " << M << ";\n";
1680   }
1681   OS << "  return 0;\n}\n";
1682 }
1683 
1684 //
1685 // ParseFeaturesFunction - Produces a subtarget specific function for parsing
1686 // the subtarget features string.
1687 //
ParseFeaturesFunction(raw_ostream & OS,unsigned NumFeatures,unsigned NumProcs)1688 void SubtargetEmitter::ParseFeaturesFunction(raw_ostream &OS,
1689                                              unsigned NumFeatures,
1690                                              unsigned NumProcs) {
1691   std::vector<Record*> Features =
1692                        Records.getAllDerivedDefinitions("SubtargetFeature");
1693   llvm::sort(Features, LessRecord());
1694 
1695   OS << "// ParseSubtargetFeatures - Parses features string setting specified\n"
1696      << "// subtarget options.\n"
1697      << "void llvm::";
1698   OS << Target;
1699   OS << "Subtarget::ParseSubtargetFeatures(StringRef CPU, StringRef FS) {\n"
1700      << "  LLVM_DEBUG(dbgs() << \"\\nFeatures:\" << FS);\n"
1701      << "  LLVM_DEBUG(dbgs() << \"\\nCPU:\" << CPU << \"\\n\\n\");\n";
1702 
1703   if (Features.empty()) {
1704     OS << "}\n";
1705     return;
1706   }
1707 
1708   OS << "  InitMCProcessorInfo(CPU, FS);\n"
1709      << "  const FeatureBitset& Bits = getFeatureBits();\n";
1710 
1711   for (Record *R : Features) {
1712     // Next record
1713     StringRef Instance = R->getName();
1714     StringRef Value = R->getValueAsString("Value");
1715     StringRef Attribute = R->getValueAsString("Attribute");
1716 
1717     if (Value=="true" || Value=="false")
1718       OS << "  if (Bits[" << Target << "::"
1719          << Instance << "]) "
1720          << Attribute << " = " << Value << ";\n";
1721     else
1722       OS << "  if (Bits[" << Target << "::"
1723          << Instance << "] && "
1724          << Attribute << " < " << Value << ") "
1725          << Attribute << " = " << Value << ";\n";
1726   }
1727 
1728   OS << "}\n";
1729 }
1730 
emitGenMCSubtargetInfo(raw_ostream & OS)1731 void SubtargetEmitter::emitGenMCSubtargetInfo(raw_ostream &OS) {
1732   OS << "namespace " << Target << "_MC {\n"
1733      << "unsigned resolveVariantSchedClassImpl(unsigned SchedClass,\n"
1734      << "    const MCInst *MI, unsigned CPUID) {\n";
1735   emitSchedModelHelpersImpl(OS, /* OnlyExpandMCPredicates */ true);
1736   OS << "}\n";
1737   OS << "} // end of namespace " << Target << "_MC\n\n";
1738 
1739   OS << "struct " << Target
1740      << "GenMCSubtargetInfo : public MCSubtargetInfo {\n";
1741   OS << "  " << Target << "GenMCSubtargetInfo(const Triple &TT, \n"
1742      << "    StringRef CPU, StringRef FS, ArrayRef<SubtargetFeatureKV> PF,\n"
1743      << "    ArrayRef<SubtargetFeatureKV> PD,\n"
1744      << "    const SubtargetInfoKV *ProcSched,\n"
1745      << "    const MCWriteProcResEntry *WPR,\n"
1746      << "    const MCWriteLatencyEntry *WL,\n"
1747      << "    const MCReadAdvanceEntry *RA, const InstrStage *IS,\n"
1748      << "    const unsigned *OC, const unsigned *FP) :\n"
1749      << "      MCSubtargetInfo(TT, CPU, FS, PF, PD, ProcSched,\n"
1750      << "                      WPR, WL, RA, IS, OC, FP) { }\n\n"
1751      << "  unsigned resolveVariantSchedClass(unsigned SchedClass,\n"
1752      << "      const MCInst *MI, unsigned CPUID) const override {\n"
1753      << "    return " << Target << "_MC"
1754      << "::resolveVariantSchedClassImpl(SchedClass, MI, CPUID); \n";
1755   OS << "  }\n";
1756   OS << "};\n";
1757 }
1758 
EmitMCInstrAnalysisPredicateFunctions(raw_ostream & OS)1759 void SubtargetEmitter::EmitMCInstrAnalysisPredicateFunctions(raw_ostream &OS) {
1760   OS << "\n#ifdef GET_STIPREDICATE_DECLS_FOR_MC_ANALYSIS\n";
1761   OS << "#undef GET_STIPREDICATE_DECLS_FOR_MC_ANALYSIS\n\n";
1762 
1763   STIPredicateExpander PE(Target);
1764   PE.setExpandForMC(true);
1765   PE.setByRef(true);
1766   for (const STIPredicateFunction &Fn : SchedModels.getSTIPredicates())
1767     PE.expandSTIPredicate(OS, Fn);
1768 
1769   OS << "#endif // GET_STIPREDICATE_DECLS_FOR_MC_ANALYSIS\n\n";
1770 
1771   OS << "\n#ifdef GET_STIPREDICATE_DEFS_FOR_MC_ANALYSIS\n";
1772   OS << "#undef GET_STIPREDICATE_DEFS_FOR_MC_ANALYSIS\n\n";
1773 
1774   std::string ClassPrefix = Target + "MCInstrAnalysis";
1775   PE.setExpandDefinition(true);
1776   PE.setClassPrefix(ClassPrefix);
1777   PE.setIndentLevel(0);
1778   for (const STIPredicateFunction &Fn : SchedModels.getSTIPredicates())
1779     PE.expandSTIPredicate(OS, Fn);
1780 
1781   OS << "#endif // GET_STIPREDICATE_DEFS_FOR_MC_ANALYSIS\n\n";
1782 }
1783 
1784 //
1785 // SubtargetEmitter::run - Main subtarget enumeration emitter.
1786 //
run(raw_ostream & OS)1787 void SubtargetEmitter::run(raw_ostream &OS) {
1788   emitSourceFileHeader("Subtarget Enumeration Source Fragment", OS);
1789 
1790   OS << "\n#ifdef GET_SUBTARGETINFO_ENUM\n";
1791   OS << "#undef GET_SUBTARGETINFO_ENUM\n\n";
1792 
1793   OS << "namespace llvm {\n";
1794   Enumeration(OS);
1795   OS << "} // end namespace llvm\n\n";
1796   OS << "#endif // GET_SUBTARGETINFO_ENUM\n\n";
1797 
1798   OS << "\n#ifdef GET_SUBTARGETINFO_MC_DESC\n";
1799   OS << "#undef GET_SUBTARGETINFO_MC_DESC\n\n";
1800 
1801   OS << "namespace llvm {\n";
1802 #if 0
1803   OS << "namespace {\n";
1804 #endif
1805   unsigned NumFeatures = FeatureKeyValues(OS);
1806   OS << "\n";
1807   unsigned NumProcs = CPUKeyValues(OS);
1808   OS << "\n";
1809   EmitSchedModel(OS);
1810   OS << "\n";
1811 #if 0
1812   OS << "} // end anonymous namespace\n\n";
1813 #endif
1814 
1815   // MCInstrInfo initialization routine.
1816   emitGenMCSubtargetInfo(OS);
1817 
1818   OS << "\nstatic inline MCSubtargetInfo *create" << Target
1819      << "MCSubtargetInfoImpl("
1820      << "const Triple &TT, StringRef CPU, StringRef FS) {\n";
1821   OS << "  return new " << Target << "GenMCSubtargetInfo(TT, CPU, FS, ";
1822   if (NumFeatures)
1823     OS << Target << "FeatureKV, ";
1824   else
1825     OS << "None, ";
1826   if (NumProcs)
1827     OS << Target << "SubTypeKV, ";
1828   else
1829     OS << "None, ";
1830   OS << '\n'; OS.indent(22);
1831   OS << Target << "ProcSchedKV, "
1832      << Target << "WriteProcResTable, "
1833      << Target << "WriteLatencyTable, "
1834      << Target << "ReadAdvanceTable, ";
1835   OS << '\n'; OS.indent(22);
1836   if (SchedModels.hasItineraries()) {
1837     OS << Target << "Stages, "
1838        << Target << "OperandCycles, "
1839        << Target << "ForwardingPaths";
1840   } else
1841     OS << "nullptr, nullptr, nullptr";
1842   OS << ");\n}\n\n";
1843 
1844   OS << "} // end namespace llvm\n\n";
1845 
1846   OS << "#endif // GET_SUBTARGETINFO_MC_DESC\n\n";
1847 
1848   OS << "\n#ifdef GET_SUBTARGETINFO_TARGET_DESC\n";
1849   OS << "#undef GET_SUBTARGETINFO_TARGET_DESC\n\n";
1850 
1851   OS << "#include \"llvm/Support/Debug.h\"\n";
1852   OS << "#include \"llvm/Support/raw_ostream.h\"\n\n";
1853   ParseFeaturesFunction(OS, NumFeatures, NumProcs);
1854 
1855   OS << "#endif // GET_SUBTARGETINFO_TARGET_DESC\n\n";
1856 
1857   // Create a TargetSubtargetInfo subclass to hide the MC layer initialization.
1858   OS << "\n#ifdef GET_SUBTARGETINFO_HEADER\n";
1859   OS << "#undef GET_SUBTARGETINFO_HEADER\n\n";
1860 
1861   std::string ClassName = Target + "GenSubtargetInfo";
1862   OS << "namespace llvm {\n";
1863   OS << "class DFAPacketizer;\n";
1864   OS << "namespace " << Target << "_MC {\n"
1865      << "unsigned resolveVariantSchedClassImpl(unsigned SchedClass,"
1866      << " const MCInst *MI, unsigned CPUID);\n"
1867      << "}\n\n";
1868   OS << "struct " << ClassName << " : public TargetSubtargetInfo {\n"
1869      << "  explicit " << ClassName << "(const Triple &TT, StringRef CPU, "
1870      << "StringRef FS);\n"
1871      << "public:\n"
1872      << "  unsigned resolveSchedClass(unsigned SchedClass, "
1873      << " const MachineInstr *DefMI,"
1874      << " const TargetSchedModel *SchedModel) const override;\n"
1875      << "  unsigned resolveVariantSchedClass(unsigned SchedClass,"
1876      << " const MCInst *MI, unsigned CPUID) const override;\n"
1877      << "  DFAPacketizer *createDFAPacketizer(const InstrItineraryData *IID)"
1878      << " const;\n";
1879   if (TGT.getHwModes().getNumModeIds() > 1)
1880     OS << "  unsigned getHwMode() const override;\n";
1881 
1882   STIPredicateExpander PE(Target);
1883   PE.setByRef(false);
1884   for (const STIPredicateFunction &Fn : SchedModels.getSTIPredicates())
1885     PE.expandSTIPredicate(OS, Fn);
1886 
1887   OS << "};\n"
1888      << "} // end namespace llvm\n\n";
1889 
1890   OS << "#endif // GET_SUBTARGETINFO_HEADER\n\n";
1891 
1892   OS << "\n#ifdef GET_SUBTARGETINFO_CTOR\n";
1893   OS << "#undef GET_SUBTARGETINFO_CTOR\n\n";
1894 
1895   OS << "#include \"llvm/CodeGen/TargetSchedule.h\"\n\n";
1896   OS << "namespace llvm {\n";
1897   OS << "extern const llvm::SubtargetFeatureKV " << Target << "FeatureKV[];\n";
1898   OS << "extern const llvm::SubtargetFeatureKV " << Target << "SubTypeKV[];\n";
1899   OS << "extern const llvm::SubtargetInfoKV " << Target << "ProcSchedKV[];\n";
1900   OS << "extern const llvm::MCWriteProcResEntry "
1901      << Target << "WriteProcResTable[];\n";
1902   OS << "extern const llvm::MCWriteLatencyEntry "
1903      << Target << "WriteLatencyTable[];\n";
1904   OS << "extern const llvm::MCReadAdvanceEntry "
1905      << Target << "ReadAdvanceTable[];\n";
1906 
1907   if (SchedModels.hasItineraries()) {
1908     OS << "extern const llvm::InstrStage " << Target << "Stages[];\n";
1909     OS << "extern const unsigned " << Target << "OperandCycles[];\n";
1910     OS << "extern const unsigned " << Target << "ForwardingPaths[];\n";
1911   }
1912 
1913   OS << ClassName << "::" << ClassName << "(const Triple &TT, StringRef CPU, "
1914      << "StringRef FS)\n"
1915      << "  : TargetSubtargetInfo(TT, CPU, FS, ";
1916   if (NumFeatures)
1917     OS << "makeArrayRef(" << Target << "FeatureKV, " << NumFeatures << "), ";
1918   else
1919     OS << "None, ";
1920   if (NumProcs)
1921     OS << "makeArrayRef(" << Target << "SubTypeKV, " << NumProcs << "), ";
1922   else
1923     OS << "None, ";
1924   OS << '\n'; OS.indent(24);
1925   OS << Target << "ProcSchedKV, "
1926      << Target << "WriteProcResTable, "
1927      << Target << "WriteLatencyTable, "
1928      << Target << "ReadAdvanceTable, ";
1929   OS << '\n'; OS.indent(24);
1930   if (SchedModels.hasItineraries()) {
1931     OS << Target << "Stages, "
1932        << Target << "OperandCycles, "
1933        << Target << "ForwardingPaths";
1934   } else
1935     OS << "nullptr, nullptr, nullptr";
1936   OS << ") {}\n\n";
1937 
1938   EmitSchedModelHelpers(ClassName, OS);
1939   EmitHwModeCheck(ClassName, OS);
1940 
1941   OS << "} // end namespace llvm\n\n";
1942 
1943   OS << "#endif // GET_SUBTARGETINFO_CTOR\n\n";
1944 
1945   EmitMCInstrAnalysisPredicateFunctions(OS);
1946 }
1947 
1948 namespace llvm {
1949 
EmitSubtarget(RecordKeeper & RK,raw_ostream & OS)1950 void EmitSubtarget(RecordKeeper &RK, raw_ostream &OS) {
1951   CodeGenTarget CGTarget(RK);
1952   SubtargetEmitter(RK, CGTarget).run(OS);
1953 }
1954 
1955 } // end namespace llvm
1956