lib/IR/LegacyPassManager.cpp

   1 //===- LegacyPassManager.cpp - LLVM Pass Infrastructure Implementation ----===//
   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 file implements the legacy LLVM Pass Manager infrastructure.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/IR/LegacyPassManager.h"
  15 #include "llvm/ADT/MapVector.h"
  16 #include "llvm/ADT/Statistic.h"
  17 #include "llvm/IR/DiagnosticInfo.h"
  18 #include "llvm/IR/IRPrintingPasses.h"
  19 #include "llvm/IR/LLVMContext.h"
  20 #include "llvm/IR/LegacyPassManagers.h"
  21 #include "llvm/IR/LegacyPassNameParser.h"
  22 #include "llvm/IR/Module.h"
  23 #include "llvm/IR/PassTimingInfo.h"
  24 #include "llvm/Support/Chrono.h"
  25 #include "llvm/Support/CommandLine.h"
  26 #include "llvm/Support/Debug.h"
  27 #include "llvm/Support/Error.h"
  28 #include "llvm/Support/ErrorHandling.h"
  29 #include "llvm/Support/ManagedStatic.h"
  30 #include "llvm/Support/Mutex.h"
  31 #include "llvm/Support/Timer.h"
  32 #include "llvm/Support/raw_ostream.h"
  33 #include <algorithm>
  34 #include <unordered_set>
  35 using namespace llvm;
  36 using namespace llvm::legacy;
  37
  38 // See PassManagers.h for Pass Manager infrastructure overview.
  39
  40 //===----------------------------------------------------------------------===//
  41 // Pass debugging information.  Often it is useful to find out what pass is
  42 // running when a crash occurs in a utility.  When this library is compiled with
  43 // debugging on, a command line option (--debug-pass) is enabled that causes the
  44 // pass name to be printed before it executes.
  45 //
  46
  47 namespace {
  48 // Different debug levels that can be enabled...
  49 enum PassDebugLevel {
  50   Disabled, Arguments, Structure, Executions, Details
  51 };
  52 }
  53
  54 static cl::opt<enum PassDebugLevel>
  55 PassDebugging("debug-pass", cl::Hidden,
  56                   cl::desc("Print PassManager debugging information"),
  57                   cl::values(
  58   clEnumVal(Disabled  , "disable debug output"),
  59   clEnumVal(Arguments , "print pass arguments to pass to 'opt'"),
  60   clEnumVal(Structure , "print pass structure before run()"),
  61   clEnumVal(Executions, "print pass name before it is executed"),
  62   clEnumVal(Details   , "print pass details when it is executed")));
  63
  64 namespace {
  65 typedef llvm::cl::list<const llvm::PassInfo *, bool, PassNameParser>
  66 PassOptionList;
  67 }
  68
  69 // Print IR out before/after specified passes.
  70 static PassOptionList
  71 PrintBefore("print-before",
  72             llvm::cl::desc("Print IR before specified passes"),
  73             cl::Hidden);
  74
  75 static PassOptionList
  76 PrintAfter("print-after",
  77            llvm::cl::desc("Print IR after specified passes"),
  78            cl::Hidden);
  79
  80 static cl::opt<bool> PrintBeforeAll("print-before-all",
  81                                     llvm::cl::desc("Print IR before each pass"),
  82                                     cl::init(false), cl::Hidden);
  83 static cl::opt<bool> PrintAfterAll("print-after-all",
  84                                    llvm::cl::desc("Print IR after each pass"),
  85                                    cl::init(false), cl::Hidden);
  86
  87 static cl::opt<bool>
  88     PrintModuleScope("print-module-scope",
  89                      cl::desc("When printing IR for print-[before|after]{-all} "
  90                               "always print a module IR"),
  91                      cl::init(false), cl::Hidden);
  92
  93 static cl::list<std::string>
  94     PrintFuncsList("filter-print-funcs", cl::value_desc("function names"),
  95                    cl::desc("Only print IR for functions whose name "
  96                             "match this for all print-[before|after][-all] "
  97                             "options"),
  98                    cl::CommaSeparated, cl::Hidden);
  99
 100 /// This is a helper to determine whether to print IR before or
 101 /// after a pass.
 102
 103 static bool ShouldPrintBeforeOrAfterPass(const PassInfo *PI,
 104                                          PassOptionList &PassesToPrint) {
 105   for (auto *PassInf : PassesToPrint) {
 106     if (PassInf)
 107       if (PassInf->getPassArgument() == PI->getPassArgument()) {
 108         return true;
 109       }
 110   }
 111   return false;
 112 }
 113
 114 /// This is a utility to check whether a pass should have IR dumped
 115 /// before it.
 116 static bool ShouldPrintBeforePass(const PassInfo *PI) {
 117   return PrintBeforeAll || ShouldPrintBeforeOrAfterPass(PI, PrintBefore);
 118 }
 119
 120 /// This is a utility to check whether a pass should have IR dumped
 121 /// after it.
 122 static bool ShouldPrintAfterPass(const PassInfo *PI) {
 123   return PrintAfterAll || ShouldPrintBeforeOrAfterPass(PI, PrintAfter);
 124 }
 125
 126 bool llvm::forcePrintModuleIR() { return PrintModuleScope; }
 127
 128 bool llvm::isFunctionInPrintList(StringRef FunctionName) {
 129   static std::unordered_set<std::string> PrintFuncNames(PrintFuncsList.begin(),
 130                                                         PrintFuncsList.end());
 131   return PrintFuncNames.empty() || PrintFuncNames.count(FunctionName);
 132 }
 133 /// isPassDebuggingExecutionsOrMore - Return true if -debug-pass=Executions
 134 /// or higher is specified.
 135 bool PMDataManager::isPassDebuggingExecutionsOrMore() const {
 136   return PassDebugging >= Executions;
 137 }
 138
 139 unsigned PMDataManager::initSizeRemarkInfo(
 140     Module &M, StringMap<std::pair<unsigned, unsigned>> &FunctionToInstrCount) {
 141   // Only calculate getInstructionCount if the size-info remark is requested.
 142   unsigned InstrCount = 0;
 143
 144   // Collect instruction counts for every function. We'll use this to emit
 145   // per-function size remarks later.
 146   for (Function &F : M) {
 147     unsigned FCount = F.getInstructionCount();
 148
 149     // Insert a record into FunctionToInstrCount keeping track of the current
 150     // size of the function as the first member of a pair. Set the second
 151     // member to 0; if the function is deleted by the pass, then when we get
 152     // here, we'll be able to let the user know that F no longer contributes to
 153     // the module.
 154     FunctionToInstrCount[F.getName().str()] =
 155         std::pair<unsigned, unsigned>(FCount, 0);
 156     InstrCount += FCount;
 157   }
 158   return InstrCount;
 159 }
 160
 161 void PMDataManager::emitInstrCountChangedRemark(
 162     Pass *P, Module &M, int64_t Delta, unsigned CountBefore,
 163     StringMap<std::pair<unsigned, unsigned>> &FunctionToInstrCount,
 164     Function *F) {
 165   // If it's a pass manager, don't emit a remark. (This hinges on the assumption
 166   // that the only passes that return non-null with getAsPMDataManager are pass
 167   // managers.) The reason we have to do this is to avoid emitting remarks for
 168   // CGSCC passes.
 169   if (P->getAsPMDataManager())
 170     return;
 171
 172   // Set to true if this isn't a module pass or CGSCC pass.
 173   bool CouldOnlyImpactOneFunction = (F != nullptr);
 174
 175   // Helper lambda that updates the changes to the size of some function.
 176   auto UpdateFunctionChanges =
 177       [&FunctionToInstrCount](Function &MaybeChangedFn) {
 178         // Update the total module count.
 179         unsigned FnSize = MaybeChangedFn.getInstructionCount();
 180         auto It = FunctionToInstrCount.find(MaybeChangedFn.getName());
 181
 182         // If we created a new function, then we need to add it to the map and
 183         // say that it changed from 0 instructions to FnSize.
 184         if (It == FunctionToInstrCount.end()) {
 185           FunctionToInstrCount[MaybeChangedFn.getName()] =
 186               std::pair<unsigned, unsigned>(0, FnSize);
 187           return;
 188         }
 189         // Insert the new function size into the second member of the pair. This
 190         // tells us whether or not this function changed in size.
 191         It->second.second = FnSize;
 192       };
 193
 194   // We need to initially update all of the function sizes.
 195   // If no function was passed in, then we're either a module pass or an
 196   // CGSCC pass.
 197   if (!CouldOnlyImpactOneFunction)
 198     std::for_each(M.begin(), M.end(), UpdateFunctionChanges);
 199   else
 200     UpdateFunctionChanges(*F);
 201
 202   // Do we have a function we can use to emit a remark?
 203   if (!CouldOnlyImpactOneFunction) {
 204     // We need a function containing at least one basic block in order to output
 205     // remarks. Since it's possible that the first function in the module
 206     // doesn't actually contain a basic block, we have to go and find one that's
 207     // suitable for emitting remarks.
 208     auto It = std::find_if(M.begin(), M.end(),
 209                           [](const Function &Fn) { return !Fn.empty(); });
 210
 211     // Didn't find a function. Quit.
 212     if (It == M.end())
 213       return;
 214
 215     // We found a function containing at least one basic block.
 216     F = &*It;
 217   }
 218   int64_t CountAfter = static_cast<int64_t>(CountBefore) + Delta;
 219   BasicBlock &BB = *F->begin();
 220   OptimizationRemarkAnalysis R("size-info", "IRSizeChange",
 221                                DiagnosticLocation(), &BB);
 222   // FIXME: Move ore namespace to DiagnosticInfo so that we can use it. This
 223   // would let us use NV instead of DiagnosticInfoOptimizationBase::Argument.
 224   R << DiagnosticInfoOptimizationBase::Argument("Pass", P->getPassName())
 225     << ": IR instruction count changed from "
 226     << DiagnosticInfoOptimizationBase::Argument("IRInstrsBefore", CountBefore)
 227     << " to "
 228     << DiagnosticInfoOptimizationBase::Argument("IRInstrsAfter", CountAfter)
 229     << "; Delta: "
 230     << DiagnosticInfoOptimizationBase::Argument("DeltaInstrCount", Delta);
 231   F->getContext().diagnose(R); // Not using ORE for layering reasons.
 232
 233   // Emit per-function size change remarks separately.
 234   std::string PassName = P->getPassName().str();
 235
 236   // Helper lambda that emits a remark when the size of a function has changed.
 237   auto EmitFunctionSizeChangedRemark = [&FunctionToInstrCount, &F, &BB,
 238                                         &PassName](const std::string &Fname) {
 239     unsigned FnCountBefore, FnCountAfter;
 240     std::pair<unsigned, unsigned> &Change = FunctionToInstrCount[Fname];
 241     std::tie(FnCountBefore, FnCountAfter) = Change;
 242     int64_t FnDelta = static_cast<int64_t>(FnCountAfter) -
 243                       static_cast<int64_t>(FnCountBefore);
 244
 245     if (FnDelta == 0)
 246       return;
 247
 248     // FIXME: We shouldn't use BB for the location here. Unfortunately, because
 249     // the function that we're looking at could have been deleted, we can't use
 250     // it for the source location. We *want* remarks when a function is deleted
 251     // though, so we're kind of stuck here as is. (This remark, along with the
 252     // whole-module size change remarks really ought not to have source
 253     // locations at all.)
 254     OptimizationRemarkAnalysis FR("size-info", "FunctionIRSizeChange",
 255                                   DiagnosticLocation(), &BB);
 256     FR << DiagnosticInfoOptimizationBase::Argument("Pass", PassName)
 257        << ": Function: "
 258        << DiagnosticInfoOptimizationBase::Argument("Function", Fname)
 259        << ": IR instruction count changed from "
 260        << DiagnosticInfoOptimizationBase::Argument("IRInstrsBefore",
 261                                                    FnCountBefore)
 262        << " to "
 263        << DiagnosticInfoOptimizationBase::Argument("IRInstrsAfter",
 264                                                    FnCountAfter)
 265        << "; Delta: "
 266        << DiagnosticInfoOptimizationBase::Argument("DeltaInstrCount", FnDelta);
 267     F->getContext().diagnose(FR);
 268
 269     // Update the function size.
 270     Change.first = FnCountAfter;
 271   };
 272
 273   // Are we looking at more than one function? If so, emit remarks for all of
 274   // the functions in the module. Otherwise, only emit one remark.
 275   if (!CouldOnlyImpactOneFunction)
 276     std::for_each(FunctionToInstrCount.keys().begin(),
 277                   FunctionToInstrCount.keys().end(),
 278                   EmitFunctionSizeChangedRemark);
 279   else
 280     EmitFunctionSizeChangedRemark(F->getName().str());
 281 }
 282
 283 void PassManagerPrettyStackEntry::print(raw_ostream &OS) const {
 284   if (!V && !M)
 285     OS << "Releasing pass '";
 286   else
 287     OS << "Running pass '";
 288
 289   OS << P->getPassName() << "'";
 290
 291   if (M) {
 292     OS << " on module '" << M->getModuleIdentifier() << "'.\n";
 293     return;
 294   }
 295   if (!V) {
 296     OS << '\n';
 297     return;
 298   }
 299
 300   OS << " on ";
 301   if (isa<Function>(V))
 302     OS << "function";
 303   else if (isa<BasicBlock>(V))
 304     OS << "basic block";
 305   else
 306     OS << "value";
 307
 308   OS << " '";
 309   V->printAsOperand(OS, /*PrintTy=*/false, M);
 310   OS << "'\n";
 311 }
 312
 313
 314 namespace {
 315 //===----------------------------------------------------------------------===//
 316 // BBPassManager
 317 //
 318 /// BBPassManager manages BasicBlockPass. It batches all the
 319 /// pass together and sequence them to process one basic block before
 320 /// processing next basic block.
 321 class BBPassManager : public PMDataManager, public FunctionPass {
 322
 323 public:
 324   static char ID;
 325   explicit BBPassManager()
 326     : PMDataManager(), FunctionPass(ID) {}
 327
 328   /// Execute all of the passes scheduled for execution.  Keep track of
 329   /// whether any of the passes modifies the function, and if so, return true.
 330   bool runOnFunction(Function &F) override;
 331
 332   /// Pass Manager itself does not invalidate any analysis info.
 333   void getAnalysisUsage(AnalysisUsage &Info) const override {
 334     Info.setPreservesAll();
 335   }
 336
 337   bool doInitialization(Module &M) override;
 338   bool doInitialization(Function &F);
 339   bool doFinalization(Module &M) override;
 340   bool doFinalization(Function &F);
 341
 342   PMDataManager *getAsPMDataManager() override { return this; }
 343   Pass *getAsPass() override { return this; }
 344
 345   StringRef getPassName() const override { return "BasicBlock Pass Manager"; }
 346
 347   // Print passes managed by this manager
 348   void dumpPassStructure(unsigned Offset) override {
 349     dbgs().indent(Offset*2) << "BasicBlockPass Manager\n";
 350     for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
 351       BasicBlockPass *BP = getContainedPass(Index);
 352       BP->dumpPassStructure(Offset + 1);
 353       dumpLastUses(BP, Offset+1);
 354     }
 355   }
 356
 357   BasicBlockPass *getContainedPass(unsigned N) {
 358     assert(N < PassVector.size() && "Pass number out of range!");
 359     BasicBlockPass *BP = static_cast<BasicBlockPass *>(PassVector[N]);
 360     return BP;
 361   }
 362
 363   PassManagerType getPassManagerType() const override {
 364     return PMT_BasicBlockPassManager;
 365   }
 366 };
 367
 368 char BBPassManager::ID = 0;
 369 } // End anonymous namespace
 370
 371 namespace llvm {
 372 namespace legacy {
 373 //===----------------------------------------------------------------------===//
 374 // FunctionPassManagerImpl
 375 //
 376 /// FunctionPassManagerImpl manages FPPassManagers
 377 class FunctionPassManagerImpl : public Pass,
 378                                 public PMDataManager,
 379                                 public PMTopLevelManager {
 380   virtual void anchor();
 381 private:
 382   bool wasRun;
 383 public:
 384   static char ID;
 385   explicit FunctionPassManagerImpl() :
 386     Pass(PT_PassManager, ID), PMDataManager(),
 387     PMTopLevelManager(new FPPassManager()), wasRun(false) {}
 388
 389   /// \copydoc FunctionPassManager::add()
 390   void add(Pass *P) {
 391     schedulePass(P);
 392   }
 393
 394   /// createPrinterPass - Get a function printer pass.
 395   Pass *createPrinterPass(raw_ostream &O,
 396                           const std::string &Banner) const override {
 397     return createPrintFunctionPass(O, Banner);
 398   }
 399
 400   // Prepare for running an on the fly pass, freeing memory if needed
 401   // from a previous run.
 402   void releaseMemoryOnTheFly();
 403
 404   /// run - Execute all of the passes scheduled for execution.  Keep track of
 405   /// whether any of the passes modifies the module, and if so, return true.
 406   bool run(Function &F);
 407
 408   /// doInitialization - Run all of the initializers for the function passes.
 409   ///
 410   bool doInitialization(Module &M) override;
 411
 412   /// doFinalization - Run all of the finalizers for the function passes.
 413   ///
 414   bool doFinalization(Module &M) override;
 415
 416
 417   PMDataManager *getAsPMDataManager() override { return this; }
 418   Pass *getAsPass() override { return this; }
 419   PassManagerType getTopLevelPassManagerType() override {
 420     return PMT_FunctionPassManager;
 421   }
 422
 423   /// Pass Manager itself does not invalidate any analysis info.
 424   void getAnalysisUsage(AnalysisUsage &Info) const override {
 425     Info.setPreservesAll();
 426   }
 427
 428   FPPassManager *getContainedManager(unsigned N) {
 429     assert(N < PassManagers.size() && "Pass number out of range!");
 430     FPPassManager *FP = static_cast<FPPassManager *>(PassManagers[N]);
 431     return FP;
 432   }
 433 };
 434
 435 void FunctionPassManagerImpl::anchor() {}
 436
 437 char FunctionPassManagerImpl::ID = 0;
 438 } // End of legacy namespace
 439 } // End of llvm namespace
 440
 441 namespace {
 442 //===----------------------------------------------------------------------===//
 443 // MPPassManager
 444 //
 445 /// MPPassManager manages ModulePasses and function pass managers.
 446 /// It batches all Module passes and function pass managers together and
 447 /// sequences them to process one module.
 448 class MPPassManager : public Pass, public PMDataManager {
 449 public:
 450   static char ID;
 451   explicit MPPassManager() :
 452     Pass(PT_PassManager, ID), PMDataManager() { }
 453
 454   // Delete on the fly managers.
 455   ~MPPassManager() override {
 456     for (auto &OnTheFlyManager : OnTheFlyManagers) {
 457       FunctionPassManagerImpl *FPP = OnTheFlyManager.second;
 458       delete FPP;
 459     }
 460   }
 461
 462   /// createPrinterPass - Get a module printer pass.
 463   Pass *createPrinterPass(raw_ostream &O,
 464                           const std::string &Banner) const override {
 465     return createPrintModulePass(O, Banner);
 466   }
 467
 468   /// run - Execute all of the passes scheduled for execution.  Keep track of
 469   /// whether any of the passes modifies the module, and if so, return true.
 470   bool runOnModule(Module &M);
 471
 472   using llvm::Pass::doInitialization;
 473   using llvm::Pass::doFinalization;
 474
 475   /// Pass Manager itself does not invalidate any analysis info.
 476   void getAnalysisUsage(AnalysisUsage &Info) const override {
 477     Info.setPreservesAll();
 478   }
 479
 480   /// Add RequiredPass into list of lower level passes required by pass P.
 481   /// RequiredPass is run on the fly by Pass Manager when P requests it
 482   /// through getAnalysis interface.
 483   void addLowerLevelRequiredPass(Pass *P, Pass *RequiredPass) override;
 484
 485   /// Return function pass corresponding to PassInfo PI, that is
 486   /// required by module pass MP. Instantiate analysis pass, by using
 487   /// its runOnFunction() for function F.
 488   Pass* getOnTheFlyPass(Pass *MP, AnalysisID PI, Function &F) override;
 489
 490   StringRef getPassName() const override { return "Module Pass Manager"; }
 491
 492   PMDataManager *getAsPMDataManager() override { return this; }
 493   Pass *getAsPass() override { return this; }
 494
 495   // Print passes managed by this manager
 496   void dumpPassStructure(unsigned Offset) override {
 497     dbgs().indent(Offset*2) << "ModulePass Manager\n";
 498     for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
 499       ModulePass *MP = getContainedPass(Index);
 500       MP->dumpPassStructure(Offset + 1);
 501       MapVector<Pass *, FunctionPassManagerImpl *>::const_iterator I =
 502           OnTheFlyManagers.find(MP);
 503       if (I != OnTheFlyManagers.end())
 504         I->second->dumpPassStructure(Offset + 2);
 505       dumpLastUses(MP, Offset+1);
 506     }
 507   }
 508
 509   ModulePass *getContainedPass(unsigned N) {
 510     assert(N < PassVector.size() && "Pass number out of range!");
 511     return static_cast<ModulePass *>(PassVector[N]);
 512   }
 513
 514   PassManagerType getPassManagerType() const override {
 515     return PMT_ModulePassManager;
 516   }
 517
 518  private:
 519   /// Collection of on the fly FPPassManagers. These managers manage
 520   /// function passes that are required by module passes.
 521    MapVector<Pass *, FunctionPassManagerImpl *> OnTheFlyManagers;
 522 };
 523
 524 char MPPassManager::ID = 0;
 525 } // End anonymous namespace
 526
 527 namespace llvm {
 528 namespace legacy {
 529 //===----------------------------------------------------------------------===//
 530 // PassManagerImpl
 531 //
 532
 533 /// PassManagerImpl manages MPPassManagers
 534 class PassManagerImpl : public Pass,
 535                         public PMDataManager,
 536                         public PMTopLevelManager {
 537   virtual void anchor();
 538
 539 public:
 540   static char ID;
 541   explicit PassManagerImpl() :
 542     Pass(PT_PassManager, ID), PMDataManager(),
 543                               PMTopLevelManager(new MPPassManager()) {}
 544
 545   /// \copydoc PassManager::add()
 546   void add(Pass *P) {
 547     schedulePass(P);
 548   }
 549
 550   /// createPrinterPass - Get a module printer pass.
 551   Pass *createPrinterPass(raw_ostream &O,
 552                           const std::string &Banner) const override {
 553     return createPrintModulePass(O, Banner);
 554   }
 555
 556   /// run - Execute all of the passes scheduled for execution.  Keep track of
 557   /// whether any of the passes modifies the module, and if so, return true.
 558   bool run(Module &M);
 559
 560   using llvm::Pass::doInitialization;
 561   using llvm::Pass::doFinalization;
 562
 563   /// Pass Manager itself does not invalidate any analysis info.
 564   void getAnalysisUsage(AnalysisUsage &Info) const override {
 565     Info.setPreservesAll();
 566   }
 567
 568   PMDataManager *getAsPMDataManager() override { return this; }
 569   Pass *getAsPass() override { return this; }
 570   PassManagerType getTopLevelPassManagerType() override {
 571     return PMT_ModulePassManager;
 572   }
 573
 574   MPPassManager *getContainedManager(unsigned N) {
 575     assert(N < PassManagers.size() && "Pass number out of range!");
 576     MPPassManager *MP = static_cast<MPPassManager *>(PassManagers[N]);
 577     return MP;
 578   }
 579 };
 580
 581 void PassManagerImpl::anchor() {}
 582
 583 char PassManagerImpl::ID = 0;
 584 } // End of legacy namespace
 585 } // End of llvm namespace
 586
 587 //===----------------------------------------------------------------------===//
 588 // PMTopLevelManager implementation
 589
 590 /// Initialize top level manager. Create first pass manager.
 591 PMTopLevelManager::PMTopLevelManager(PMDataManager *PMDM) {
 592   PMDM->setTopLevelManager(this);
 593   addPassManager(PMDM);
 594   activeStack.push(PMDM);
 595 }
 596
 597 /// Set pass P as the last user of the given analysis passes.
 598 void
 599 PMTopLevelManager::setLastUser(ArrayRef<Pass*> AnalysisPasses, Pass *P) {
 600   unsigned PDepth = 0;
 601   if (P->getResolver())
 602     PDepth = P->getResolver()->getPMDataManager().getDepth();
 603
 604   for (Pass *AP : AnalysisPasses) {
 605     LastUser[AP] = P;
 606
 607     if (P == AP)
 608       continue;
 609
 610     // Update the last users of passes that are required transitive by AP.
 611     AnalysisUsage *AnUsage = findAnalysisUsage(AP);
 612     const AnalysisUsage::VectorType &IDs = AnUsage->getRequiredTransitiveSet();
 613     SmallVector<Pass *, 12> LastUses;
 614     SmallVector<Pass *, 12> LastPMUses;
 615     for (AnalysisID ID : IDs) {
 616       Pass *AnalysisPass = findAnalysisPass(ID);
 617       assert(AnalysisPass && "Expected analysis pass to exist.");
 618       AnalysisResolver *AR = AnalysisPass->getResolver();
 619       assert(AR && "Expected analysis resolver to exist.");
 620       unsigned APDepth = AR->getPMDataManager().getDepth();
 621
 622       if (PDepth == APDepth)
 623         LastUses.push_back(AnalysisPass);
 624       else if (PDepth > APDepth)
 625         LastPMUses.push_back(AnalysisPass);
 626     }
 627
 628     setLastUser(LastUses, P);
 629
 630     // If this pass has a corresponding pass manager, push higher level
 631     // analysis to this pass manager.
 632     if (P->getResolver())
 633       setLastUser(LastPMUses, P->getResolver()->getPMDataManager().getAsPass());
 634
 635
 636     // If AP is the last user of other passes then make P last user of
 637     // such passes.
 638     for (auto LU : LastUser) {
 639       if (LU.second == AP)
 640         // DenseMap iterator is not invalidated here because
 641         // this is just updating existing entries.
 642         LastUser[LU.first] = P;
 643     }
 644   }
 645 }
 646
 647 /// Collect passes whose last user is P
 648 void PMTopLevelManager::collectLastUses(SmallVectorImpl<Pass *> &LastUses,
 649                                         Pass *P) {
 650   DenseMap<Pass *, SmallPtrSet<Pass *, 8> >::iterator DMI =
 651     InversedLastUser.find(P);
 652   if (DMI == InversedLastUser.end())
 653     return;
 654
 655   SmallPtrSet<Pass *, 8> &LU = DMI->second;
 656   for (Pass *LUP : LU) {
 657     LastUses.push_back(LUP);
 658   }
 659
 660 }
 661
 662 AnalysisUsage *PMTopLevelManager::findAnalysisUsage(Pass *P) {
 663   AnalysisUsage *AnUsage = nullptr;
 664   auto DMI = AnUsageMap.find(P);
 665   if (DMI != AnUsageMap.end())
 666     AnUsage = DMI->second;
 667   else {
 668     // Look up the analysis usage from the pass instance (different instances
 669     // of the same pass can produce different results), but unique the
 670     // resulting object to reduce memory usage.  This helps to greatly reduce
 671     // memory usage when we have many instances of only a few pass types
 672     // (e.g. instcombine, simplifycfg, etc...) which tend to share a fixed set
 673     // of dependencies.
 674     AnalysisUsage AU;
 675     P->getAnalysisUsage(AU);
 676
 677     AUFoldingSetNode* Node = nullptr;
 678     FoldingSetNodeID ID;
 679     AUFoldingSetNode::Profile(ID, AU);
 680     void *IP = nullptr;
 681     if (auto *N = UniqueAnalysisUsages.FindNodeOrInsertPos(ID, IP))
 682       Node = N;
 683     else {
 684       Node = new (AUFoldingSetNodeAllocator.Allocate()) AUFoldingSetNode(AU);
 685       UniqueAnalysisUsages.InsertNode(Node, IP);
 686     }
 687     assert(Node && "cached analysis usage must be non null");
 688
 689     AnUsageMap[P] = &Node->AU;
 690     AnUsage = &Node->AU;
 691   }
 692   return AnUsage;
 693 }
 694
 695 /// Schedule pass P for execution. Make sure that passes required by
 696 /// P are run before P is run. Update analysis info maintained by
 697 /// the manager. Remove dead passes. This is a recursive function.
 698 void PMTopLevelManager::schedulePass(Pass *P) {
 699
 700   // TODO : Allocate function manager for this pass, other wise required set
 701   // may be inserted into previous function manager
 702
 703   // Give pass a chance to prepare the stage.
 704   P->preparePassManager(activeStack);
 705
 706   // If P is an analysis pass and it is available then do not
 707   // generate the analysis again. Stale analysis info should not be
 708   // available at this point.
 709   const PassInfo *PI = findAnalysisPassInfo(P->getPassID());
 710   if (PI && PI->isAnalysis() && findAnalysisPass(P->getPassID())) {
 711     // Remove any cached AnalysisUsage information.
 712     AnUsageMap.erase(P);
 713     delete P;
 714     return;
 715   }
 716
 717   AnalysisUsage *AnUsage = findAnalysisUsage(P);
 718
 719   bool checkAnalysis = true;
 720   while (checkAnalysis) {
 721     checkAnalysis = false;
 722
 723     const AnalysisUsage::VectorType &RequiredSet = AnUsage->getRequiredSet();
 724     for (const AnalysisID ID : RequiredSet) {
 725
 726       Pass *AnalysisPass = findAnalysisPass(ID);
 727       if (!AnalysisPass) {
 728         const PassInfo *PI = findAnalysisPassInfo(ID);
 729
 730         if (!PI) {
 731           // Pass P is not in the global PassRegistry
 732           dbgs() << "Pass '"  << P->getPassName() << "' is not initialized." << "\n";
 733           dbgs() << "Verify if there is a pass dependency cycle." << "\n";
 734           dbgs() << "Required Passes:" << "\n";
 735           for (const AnalysisID ID2 : RequiredSet) {
 736             if (ID == ID2)
 737               break;
 738             Pass *AnalysisPass2 = findAnalysisPass(ID2);
 739             if (AnalysisPass2) {
 740               dbgs() << "\t" << AnalysisPass2->getPassName() << "\n";
 741             } else {
 742               dbgs() << "\t"   << "Error: Required pass not found! Possible causes:"  << "\n";
 743               dbgs() << "\t\t" << "- Pass misconfiguration (e.g.: missing macros)"    << "\n";
 744               dbgs() << "\t\t" << "- Corruption of the global PassRegistry"           << "\n";
 745             }
 746           }
 747         }
 748
 749         assert(PI && "Expected required passes to be initialized");
 750         AnalysisPass = PI->createPass();
 751         if (P->getPotentialPassManagerType () ==
 752             AnalysisPass->getPotentialPassManagerType())
 753           // Schedule analysis pass that is managed by the same pass manager.
 754           schedulePass(AnalysisPass);
 755         else if (P->getPotentialPassManagerType () >
 756                  AnalysisPass->getPotentialPassManagerType()) {
 757           // Schedule analysis pass that is managed by a new manager.
 758           schedulePass(AnalysisPass);
 759           // Recheck analysis passes to ensure that required analyses that
 760           // are already checked are still available.
 761           checkAnalysis = true;
 762         } else
 763           // Do not schedule this analysis. Lower level analysis
 764           // passes are run on the fly.
 765           delete AnalysisPass;
 766       }
 767     }
 768   }
 769
 770   // Now all required passes are available.
 771   if (ImmutablePass *IP = P->getAsImmutablePass()) {
 772     // P is a immutable pass and it will be managed by this
 773     // top level manager. Set up analysis resolver to connect them.
 774     PMDataManager *DM = getAsPMDataManager();
 775     AnalysisResolver *AR = new AnalysisResolver(*DM);
 776     P->setResolver(AR);
 777     DM->initializeAnalysisImpl(P);
 778     addImmutablePass(IP);
 779     DM->recordAvailableAnalysis(IP);
 780     return;
 781   }
 782
 783   if (PI && !PI->isAnalysis() && ShouldPrintBeforePass(PI)) {
 784     Pass *PP = P->createPrinterPass(
 785         dbgs(), ("*** IR Dump Before " + P->getPassName() + " ***").str());
 786     PP->assignPassManager(activeStack, getTopLevelPassManagerType());
 787   }
 788
 789   // Add the requested pass to the best available pass manager.
 790   P->assignPassManager(activeStack, getTopLevelPassManagerType());
 791
 792   if (PI && !PI->isAnalysis() && ShouldPrintAfterPass(PI)) {
 793     Pass *PP = P->createPrinterPass(
 794         dbgs(), ("*** IR Dump After " + P->getPassName() + " ***").str());
 795     PP->assignPassManager(activeStack, getTopLevelPassManagerType());
 796   }
 797 }
 798
 799 /// Find the pass that implements Analysis AID. Search immutable
 800 /// passes and all pass managers. If desired pass is not found
 801 /// then return NULL.
 802 Pass *PMTopLevelManager::findAnalysisPass(AnalysisID AID) {
 803   // For immutable passes we have a direct mapping from ID to pass, so check
 804   // that first.
 805   if (Pass *P = ImmutablePassMap.lookup(AID))
 806     return P;
 807
 808   // Check pass managers
 809   for (PMDataManager *PassManager : PassManagers)
 810     if (Pass *P = PassManager->findAnalysisPass(AID, false))
 811       return P;
 812
 813   // Check other pass managers
 814   for (PMDataManager *IndirectPassManager : IndirectPassManagers)
 815     if (Pass *P = IndirectPassManager->findAnalysisPass(AID, false))
 816       return P;
 817
 818   return nullptr;
 819 }
 820
 821 const PassInfo *PMTopLevelManager::findAnalysisPassInfo(AnalysisID AID) const {
 822   const PassInfo *&PI = AnalysisPassInfos[AID];
 823   if (!PI)
 824     PI = PassRegistry::getPassRegistry()->getPassInfo(AID);
 825   else
 826     assert(PI == PassRegistry::getPassRegistry()->getPassInfo(AID) &&
 827            "The pass info pointer changed for an analysis ID!");
 828
 829   return PI;
 830 }
 831
 832 void PMTopLevelManager::addImmutablePass(ImmutablePass *P) {
 833   P->initializePass();
 834   ImmutablePasses.push_back(P);
 835
 836   // Add this pass to the map from its analysis ID. We clobber any prior runs
 837   // of the pass in the map so that the last one added is the one found when
 838   // doing lookups.
 839   AnalysisID AID = P->getPassID();
 840   ImmutablePassMap[AID] = P;
 841
 842   // Also add any interfaces implemented by the immutable pass to the map for
 843   // fast lookup.
 844   const PassInfo *PassInf = findAnalysisPassInfo(AID);
 845   assert(PassInf && "Expected all immutable passes to be initialized");
 846   for (const PassInfo *ImmPI : PassInf->getInterfacesImplemented())
 847     ImmutablePassMap[ImmPI->getTypeInfo()] = P;
 848 }
 849
 850 // Print passes managed by this top level manager.
 851 void PMTopLevelManager::dumpPasses() const {
 852
 853   if (PassDebugging < Structure)
 854     return;
 855
 856   // Print out the immutable passes
 857   for (unsigned i = 0, e = ImmutablePasses.size(); i != e; ++i) {
 858     ImmutablePasses[i]->dumpPassStructure(0);
 859   }
 860
 861   // Every class that derives from PMDataManager also derives from Pass
 862   // (sometimes indirectly), but there's no inheritance relationship
 863   // between PMDataManager and Pass, so we have to getAsPass to get
 864   // from a PMDataManager* to a Pass*.
 865   for (PMDataManager *Manager : PassManagers)
 866     Manager->getAsPass()->dumpPassStructure(1);
 867 }
 868
 869 void PMTopLevelManager::dumpArguments() const {
 870
 871   if (PassDebugging < Arguments)
 872     return;
 873
 874   dbgs() << "Pass Arguments: ";
 875   for (ImmutablePass *P : ImmutablePasses)
 876     if (const PassInfo *PI = findAnalysisPassInfo(P->getPassID())) {
 877       assert(PI && "Expected all immutable passes to be initialized");
 878       if (!PI->isAnalysisGroup())
 879         dbgs() << " -" << PI->getPassArgument();
 880     }
 881   for (PMDataManager *PM : PassManagers)
 882     PM->dumpPassArguments();
 883   dbgs() << "\n";
 884 }
 885
 886 void PMTopLevelManager::initializeAllAnalysisInfo() {
 887   for (PMDataManager *PM : PassManagers)
 888     PM->initializeAnalysisInfo();
 889
 890   // Initailize other pass managers
 891   for (PMDataManager *IPM : IndirectPassManagers)
 892     IPM->initializeAnalysisInfo();
 893
 894   for (auto LU : LastUser) {
 895     SmallPtrSet<Pass *, 8> &L = InversedLastUser[LU.second];
 896     L.insert(LU.first);
 897   }
 898 }
 899
 900 /// Destructor
 901 PMTopLevelManager::~PMTopLevelManager() {
 902   for (PMDataManager *PM : PassManagers)
 903     delete PM;
 904
 905   for (ImmutablePass *P : ImmutablePasses)
 906     delete P;
 907 }
 908
 909 //===----------------------------------------------------------------------===//
 910 // PMDataManager implementation
 911
 912 /// Augement AvailableAnalysis by adding analysis made available by pass P.
 913 void PMDataManager::recordAvailableAnalysis(Pass *P) {
 914   AnalysisID PI = P->getPassID();
 915
 916   AvailableAnalysis[PI] = P;
 917
 918   assert(!AvailableAnalysis.empty());
 919
 920   // This pass is the current implementation of all of the interfaces it
 921   // implements as well.
 922   const PassInfo *PInf = TPM->findAnalysisPassInfo(PI);
 923   if (!PInf) return;
 924   const std::vector<const PassInfo*> &II = PInf->getInterfacesImplemented();
 925   for (unsigned i = 0, e = II.size(); i != e; ++i)
 926     AvailableAnalysis[II[i]->getTypeInfo()] = P;
 927 }
 928
 929 // Return true if P preserves high level analysis used by other
 930 // passes managed by this manager
 931 bool PMDataManager::preserveHigherLevelAnalysis(Pass *P) {
 932   AnalysisUsage *AnUsage = TPM->findAnalysisUsage(P);
 933   if (AnUsage->getPreservesAll())
 934     return true;
 935
 936   const AnalysisUsage::VectorType &PreservedSet = AnUsage->getPreservedSet();
 937   for (Pass *P1 : HigherLevelAnalysis) {
 938     if (P1->getAsImmutablePass() == nullptr &&
 939         !is_contained(PreservedSet, P1->getPassID()))
 940       return false;
 941   }
 942
 943   return true;
 944 }
 945
 946 /// verifyPreservedAnalysis -- Verify analysis preserved by pass P.
 947 void PMDataManager::verifyPreservedAnalysis(Pass *P) {
 948   // Don't do this unless assertions are enabled.
 949 #ifdef NDEBUG
 950   return;
 951 #endif
 952   AnalysisUsage *AnUsage = TPM->findAnalysisUsage(P);
 953   const AnalysisUsage::VectorType &PreservedSet = AnUsage->getPreservedSet();
 954
 955   // Verify preserved analysis
 956   for (AnalysisID AID : PreservedSet) {
 957     if (Pass *AP = findAnalysisPass(AID, true)) {
 958       TimeRegion PassTimer(getPassTimer(AP));
 959       AP->verifyAnalysis();
 960     }
 961   }
 962 }
 963
 964 /// Remove Analysis not preserved by Pass P
 965 void PMDataManager::removeNotPreservedAnalysis(Pass *P) {
 966   AnalysisUsage *AnUsage = TPM->findAnalysisUsage(P);
 967   if (AnUsage->getPreservesAll())
 968     return;
 969
 970   const AnalysisUsage::VectorType &PreservedSet = AnUsage->getPreservedSet();
 971   for (DenseMap<AnalysisID, Pass*>::iterator I = AvailableAnalysis.begin(),
 972          E = AvailableAnalysis.end(); I != E; ) {
 973     DenseMap<AnalysisID, Pass*>::iterator Info = I++;
 974     if (Info->second->getAsImmutablePass() == nullptr &&
 975         !is_contained(PreservedSet, Info->first)) {
 976       // Remove this analysis
 977       if (PassDebugging >= Details) {
 978         Pass *S = Info->second;
 979         dbgs() << " -- '" <<  P->getPassName() << "' is not preserving '";
 980         dbgs() << S->getPassName() << "'\n";
 981       }
 982       AvailableAnalysis.erase(Info);
 983     }
 984   }
 985
 986   // Check inherited analysis also. If P is not preserving analysis
 987   // provided by parent manager then remove it here.
 988   for (unsigned Index = 0; Index < PMT_Last; ++Index) {
 989
 990     if (!InheritedAnalysis[Index])
 991       continue;
 992
 993     for (DenseMap<AnalysisID, Pass*>::iterator
 994            I = InheritedAnalysis[Index]->begin(),
 995            E = InheritedAnalysis[Index]->end(); I != E; ) {
 996       DenseMap<AnalysisID, Pass *>::iterator Info = I++;
 997       if (Info->second->getAsImmutablePass() == nullptr &&
 998           !is_contained(PreservedSet, Info->first)) {
 999         // Remove this analysis
1000         if (PassDebugging >= Details) {
1001           Pass *S = Info->second;
1002           dbgs() << " -- '" <<  P->getPassName() << "' is not preserving '";
1003           dbgs() << S->getPassName() << "'\n";
1004         }
1005         InheritedAnalysis[Index]->erase(Info);
1006       }
1007     }
1008   }
1009 }
1010
1011 /// Remove analysis passes that are not used any longer
1012 void PMDataManager::removeDeadPasses(Pass *P, StringRef Msg,
1013                                      enum PassDebuggingString DBG_STR) {
1014
1015   SmallVector<Pass *, 12> DeadPasses;
1016
1017   // If this is a on the fly manager then it does not have TPM.
1018   if (!TPM)
1019     return;
1020
1021   TPM->collectLastUses(DeadPasses, P);
1022
1023   if (PassDebugging >= Details && !DeadPasses.empty()) {
1024     dbgs() << " -*- '" <<  P->getPassName();
1025     dbgs() << "' is the last user of following pass instances.";
1026     dbgs() << " Free these instances\n";
1027   }
1028
1029   for (Pass *P : DeadPasses)
1030     freePass(P, Msg, DBG_STR);
1031 }
1032
1033 void PMDataManager::freePass(Pass *P, StringRef Msg,
1034                              enum PassDebuggingString DBG_STR) {
1035   dumpPassInfo(P, FREEING_MSG, DBG_STR, Msg);
1036
1037   {
1038     // If the pass crashes releasing memory, remember this.
1039     PassManagerPrettyStackEntry X(P);
1040     TimeRegion PassTimer(getPassTimer(P));
1041
1042     P->releaseMemory();
1043   }
1044
1045   AnalysisID PI = P->getPassID();
1046   if (const PassInfo *PInf = TPM->findAnalysisPassInfo(PI)) {
1047     // Remove the pass itself (if it is not already removed).
1048     AvailableAnalysis.erase(PI);
1049
1050     // Remove all interfaces this pass implements, for which it is also
1051     // listed as the available implementation.
1052     const std::vector<const PassInfo*> &II = PInf->getInterfacesImplemented();
1053     for (unsigned i = 0, e = II.size(); i != e; ++i) {
1054       DenseMap<AnalysisID, Pass*>::iterator Pos =
1055         AvailableAnalysis.find(II[i]->getTypeInfo());
1056       if (Pos != AvailableAnalysis.end() && Pos->second == P)
1057         AvailableAnalysis.erase(Pos);
1058     }
1059   }
1060 }
1061
1062 /// Add pass P into the PassVector. Update
1063 /// AvailableAnalysis appropriately if ProcessAnalysis is true.
1064 void PMDataManager::add(Pass *P, bool ProcessAnalysis) {
1065   // This manager is going to manage pass P. Set up analysis resolver
1066   // to connect them.
1067   AnalysisResolver *AR = new AnalysisResolver(*this);
1068   P->setResolver(AR);
1069
1070   // If a FunctionPass F is the last user of ModulePass info M
1071   // then the F's manager, not F, records itself as a last user of M.
1072   SmallVector<Pass *, 12> TransferLastUses;
1073
1074   if (!ProcessAnalysis) {
1075     // Add pass
1076     PassVector.push_back(P);
1077     return;
1078   }
1079
1080   // At the moment, this pass is the last user of all required passes.
1081   SmallVector<Pass *, 12> LastUses;
1082   SmallVector<Pass *, 8> UsedPasses;
1083   SmallVector<AnalysisID, 8> ReqAnalysisNotAvailable;
1084
1085   unsigned PDepth = this->getDepth();
1086
1087   collectRequiredAndUsedAnalyses(UsedPasses, ReqAnalysisNotAvailable, P);
1088   for (Pass *PUsed : UsedPasses) {
1089     unsigned RDepth = 0;
1090
1091     assert(PUsed->getResolver() && "Analysis Resolver is not set");
1092     PMDataManager &DM = PUsed->getResolver()->getPMDataManager();
1093     RDepth = DM.getDepth();
1094
1095     if (PDepth == RDepth)
1096       LastUses.push_back(PUsed);
1097     else if (PDepth > RDepth) {
1098       // Let the parent claim responsibility of last use
1099       TransferLastUses.push_back(PUsed);
1100       // Keep track of higher level analysis used by this manager.
1101       HigherLevelAnalysis.push_back(PUsed);
1102     } else
1103       llvm_unreachable("Unable to accommodate Used Pass");
1104   }
1105
1106   // Set P as P's last user until someone starts using P.
1107   // However, if P is a Pass Manager then it does not need
1108   // to record its last user.
1109   if (!P->getAsPMDataManager())
1110     LastUses.push_back(P);
1111   TPM->setLastUser(LastUses, P);
1112
1113   if (!TransferLastUses.empty()) {
1114     Pass *My_PM = getAsPass();
1115     TPM->setLastUser(TransferLastUses, My_PM);
1116     TransferLastUses.clear();
1117   }
1118
1119   // Now, take care of required analyses that are not available.
1120   for (AnalysisID ID : ReqAnalysisNotAvailable) {
1121     const PassInfo *PI = TPM->findAnalysisPassInfo(ID);
1122     Pass *AnalysisPass = PI->createPass();
1123     this->addLowerLevelRequiredPass(P, AnalysisPass);
1124   }
1125
1126   // Take a note of analysis required and made available by this pass.
1127   // Remove the analysis not preserved by this pass
1128   removeNotPreservedAnalysis(P);
1129   recordAvailableAnalysis(P);
1130
1131   // Add pass
1132   PassVector.push_back(P);
1133 }
1134
1135
1136 /// Populate UP with analysis pass that are used or required by
1137 /// pass P and are available. Populate RP_NotAvail with analysis
1138 /// pass that are required by pass P but are not available.
1139 void PMDataManager::collectRequiredAndUsedAnalyses(
1140     SmallVectorImpl<Pass *> &UP, SmallVectorImpl<AnalysisID> &RP_NotAvail,
1141     Pass *P) {
1142   AnalysisUsage *AnUsage = TPM->findAnalysisUsage(P);
1143
1144   for (const auto &UsedID : AnUsage->getUsedSet())
1145     if (Pass *AnalysisPass = findAnalysisPass(UsedID, true))
1146       UP.push_back(AnalysisPass);
1147
1148   for (const auto &RequiredID : AnUsage->getRequiredSet())
1149     if (Pass *AnalysisPass = findAnalysisPass(RequiredID, true))
1150       UP.push_back(AnalysisPass);
1151     else
1152       RP_NotAvail.push_back(RequiredID);
1153
1154   for (const auto &RequiredID : AnUsage->getRequiredTransitiveSet())
1155     if (Pass *AnalysisPass = findAnalysisPass(RequiredID, true))
1156       UP.push_back(AnalysisPass);
1157     else
1158       RP_NotAvail.push_back(RequiredID);
1159 }
1160
1161 // All Required analyses should be available to the pass as it runs!  Here
1162 // we fill in the AnalysisImpls member of the pass so that it can
1163 // successfully use the getAnalysis() method to retrieve the
1164 // implementations it needs.
1165 //
1166 void PMDataManager::initializeAnalysisImpl(Pass *P) {
1167   AnalysisUsage *AnUsage = TPM->findAnalysisUsage(P);
1168
1169   for (const AnalysisID ID : AnUsage->getRequiredSet()) {
1170     Pass *Impl = findAnalysisPass(ID, true);
1171     if (!Impl)
1172       // This may be analysis pass that is initialized on the fly.
1173       // If that is not the case then it will raise an assert when it is used.
1174       continue;
1175     AnalysisResolver *AR = P->getResolver();
1176     assert(AR && "Analysis Resolver is not set");
1177     AR->addAnalysisImplsPair(ID, Impl);
1178   }
1179 }
1180
1181 /// Find the pass that implements Analysis AID. If desired pass is not found
1182 /// then return NULL.
1183 Pass *PMDataManager::findAnalysisPass(AnalysisID AID, bool SearchParent) {
1184
1185   // Check if AvailableAnalysis map has one entry.
1186   DenseMap<AnalysisID, Pass*>::const_iterator I =  AvailableAnalysis.find(AID);
1187
1188   if (I != AvailableAnalysis.end())
1189     return I->second;
1190
1191   // Search Parents through TopLevelManager
1192   if (SearchParent)
1193     return TPM->findAnalysisPass(AID);
1194
1195   return nullptr;
1196 }
1197
1198 // Print list of passes that are last used by P.
1199 void PMDataManager::dumpLastUses(Pass *P, unsigned Offset) const{
1200
1201   SmallVector<Pass *, 12> LUses;
1202
1203   // If this is a on the fly manager then it does not have TPM.
1204   if (!TPM)
1205     return;
1206
1207   TPM->collectLastUses(LUses, P);
1208
1209   for (Pass *P : LUses) {
1210     dbgs() << "--" << std::string(Offset*2, ' ');
1211     P->dumpPassStructure(0);
1212   }
1213 }
1214
1215 void PMDataManager::dumpPassArguments() const {
1216   for (Pass *P : PassVector) {
1217     if (PMDataManager *PMD = P->getAsPMDataManager())
1218       PMD->dumpPassArguments();
1219     else
1220       if (const PassInfo *PI =
1221             TPM->findAnalysisPassInfo(P->getPassID()))
1222         if (!PI->isAnalysisGroup())
1223           dbgs() << " -" << PI->getPassArgument();
1224   }
1225 }
1226
1227 void PMDataManager::dumpPassInfo(Pass *P, enum PassDebuggingString S1,
1228                                  enum PassDebuggingString S2,
1229                                  StringRef Msg) {
1230   if (PassDebugging < Executions)
1231     return;
1232   dbgs() << "[" << std::chrono::system_clock::now() << "] " << (void *)this
1233          << std::string(getDepth() * 2 + 1, ' ');
1234   switch (S1) {
1235   case EXECUTION_MSG:
1236     dbgs() << "Executing Pass '" << P->getPassName();
1237     break;
1238   case MODIFICATION_MSG:
1239     dbgs() << "Made Modification '" << P->getPassName();
1240     break;
1241   case FREEING_MSG:
1242     dbgs() << " Freeing Pass '" << P->getPassName();
1243     break;
1244   default:
1245     break;
1246   }
1247   switch (S2) {
1248   case ON_BASICBLOCK_MSG:
1249     dbgs() << "' on BasicBlock '" << Msg << "'...\n";
1250     break;
1251   case ON_FUNCTION_MSG:
1252     dbgs() << "' on Function '" << Msg << "'...\n";
1253     break;
1254   case ON_MODULE_MSG:
1255     dbgs() << "' on Module '"  << Msg << "'...\n";
1256     break;
1257   case ON_REGION_MSG:
1258     dbgs() << "' on Region '"  << Msg << "'...\n";
1259     break;
1260   case ON_LOOP_MSG:
1261     dbgs() << "' on Loop '" << Msg << "'...\n";
1262     break;
1263   case ON_CG_MSG:
1264     dbgs() << "' on Call Graph Nodes '" << Msg << "'...\n";
1265     break;
1266   default:
1267     break;
1268   }
1269 }
1270
1271 void PMDataManager::dumpRequiredSet(const Pass *P) const {
1272   if (PassDebugging < Details)
1273     return;
1274
1275   AnalysisUsage analysisUsage;
1276   P->getAnalysisUsage(analysisUsage);
1277   dumpAnalysisUsage("Required", P, analysisUsage.getRequiredSet());
1278 }
1279
1280 void PMDataManager::dumpPreservedSet(const Pass *P) const {
1281   if (PassDebugging < Details)
1282     return;
1283
1284   AnalysisUsage analysisUsage;
1285   P->getAnalysisUsage(analysisUsage);
1286   dumpAnalysisUsage("Preserved", P, analysisUsage.getPreservedSet());
1287 }
1288
1289 void PMDataManager::dumpUsedSet(const Pass *P) const {
1290   if (PassDebugging < Details)
1291     return;
1292
1293   AnalysisUsage analysisUsage;
1294   P->getAnalysisUsage(analysisUsage);
1295   dumpAnalysisUsage("Used", P, analysisUsage.getUsedSet());
1296 }
1297
1298 void PMDataManager::dumpAnalysisUsage(StringRef Msg, const Pass *P,
1299                                    const AnalysisUsage::VectorType &Set) const {
1300   assert(PassDebugging >= Details);
1301   if (Set.empty())
1302     return;
1303   dbgs() << (const void*)P << std::string(getDepth()*2+3, ' ') << Msg << " Analyses:";
1304   for (unsigned i = 0; i != Set.size(); ++i) {
1305     if (i) dbgs() << ',';
1306     const PassInfo *PInf = TPM->findAnalysisPassInfo(Set[i]);
1307     if (!PInf) {
1308       // Some preserved passes, such as AliasAnalysis, may not be initialized by
1309       // all drivers.
1310       dbgs() << " Uninitialized Pass";
1311       continue;
1312     }
1313     dbgs() << ' ' << PInf->getPassName();
1314   }
1315   dbgs() << '\n';
1316 }
1317
1318 /// Add RequiredPass into list of lower level passes required by pass P.
1319 /// RequiredPass is run on the fly by Pass Manager when P requests it
1320 /// through getAnalysis interface.
1321 /// This should be handled by specific pass manager.
1322 void PMDataManager::addLowerLevelRequiredPass(Pass *P, Pass *RequiredPass) {
1323   if (TPM) {
1324     TPM->dumpArguments();
1325     TPM->dumpPasses();
1326   }
1327
1328   // Module Level pass may required Function Level analysis info
1329   // (e.g. dominator info). Pass manager uses on the fly function pass manager
1330   // to provide this on demand. In that case, in Pass manager terminology,
1331   // module level pass is requiring lower level analysis info managed by
1332   // lower level pass manager.
1333
1334   // When Pass manager is not able to order required analysis info, Pass manager
1335   // checks whether any lower level manager will be able to provide this
1336   // analysis info on demand or not.
1337 #ifndef NDEBUG
1338   dbgs() << "Unable to schedule '" << RequiredPass->getPassName();
1339   dbgs() << "' required by '" << P->getPassName() << "'\n";
1340 #endif
1341   llvm_unreachable("Unable to schedule pass");
1342 }
1343
1344 Pass *PMDataManager::getOnTheFlyPass(Pass *P, AnalysisID PI, Function &F) {
1345   llvm_unreachable("Unable to find on the fly pass");
1346 }
1347
1348 // Destructor
1349 PMDataManager::~PMDataManager() {
1350   for (Pass *P : PassVector)
1351     delete P;
1352 }
1353
1354 //===----------------------------------------------------------------------===//
1355 // NOTE: Is this the right place to define this method ?
1356 // getAnalysisIfAvailable - Return analysis result or null if it doesn't exist.
1357 Pass *AnalysisResolver::getAnalysisIfAvailable(AnalysisID ID, bool dir) const {
1358   return PM.findAnalysisPass(ID, dir);
1359 }
1360
1361 Pass *AnalysisResolver::findImplPass(Pass *P, AnalysisID AnalysisPI,
1362                                      Function &F) {
1363   return PM.getOnTheFlyPass(P, AnalysisPI, F);
1364 }
1365
1366 //===----------------------------------------------------------------------===//
1367 // BBPassManager implementation
1368
1369 /// Execute all of the passes scheduled for execution by invoking
1370 /// runOnBasicBlock method.  Keep track of whether any of the passes modifies
1371 /// the function, and if so, return true.
1372 bool BBPassManager::runOnFunction(Function &F) {
1373   if (F.isDeclaration())
1374     return false;
1375
1376   bool Changed = doInitialization(F);
1377   Module &M = *F.getParent();
1378
1379   unsigned InstrCount, BBSize = 0;
1380   StringMap<std::pair<unsigned, unsigned>> FunctionToInstrCount;
1381   bool EmitICRemark = M.shouldEmitInstrCountChangedRemark();
1382   if (EmitICRemark)
1383     InstrCount = initSizeRemarkInfo(M, FunctionToInstrCount);
1384
1385   for (BasicBlock &BB : F) {
1386     // Collect the initial size of the basic block.
1387     if (EmitICRemark)
1388       BBSize = BB.size();
1389     for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
1390       BasicBlockPass *BP = getContainedPass(Index);
1391       bool LocalChanged = false;
1392
1393       dumpPassInfo(BP, EXECUTION_MSG, ON_BASICBLOCK_MSG, BB.getName());
1394       dumpRequiredSet(BP);
1395
1396       initializeAnalysisImpl(BP);
1397
1398       {
1399         // If the pass crashes, remember this.
1400         PassManagerPrettyStackEntry X(BP, BB);
1401         TimeRegion PassTimer(getPassTimer(BP));
1402         LocalChanged |= BP->runOnBasicBlock(BB);
1403         if (EmitICRemark) {
1404           unsigned NewSize = BB.size();
1405           // Update the size of the basic block, emit a remark, and update the
1406           // size of the module.
1407           if (NewSize != BBSize) {
1408             int64_t Delta =
1409                 static_cast<int64_t>(NewSize) - static_cast<int64_t>(BBSize);
1410             emitInstrCountChangedRemark(BP, M, Delta, InstrCount,
1411                                         FunctionToInstrCount, &F);
1412             InstrCount = static_cast<int64_t>(InstrCount) + Delta;
1413             BBSize = NewSize;
1414           }
1415         }
1416       }
1417
1418       Changed |= LocalChanged;
1419       if (LocalChanged)
1420         dumpPassInfo(BP, MODIFICATION_MSG, ON_BASICBLOCK_MSG,
1421                      BB.getName());
1422       dumpPreservedSet(BP);
1423       dumpUsedSet(BP);
1424
1425       verifyPreservedAnalysis(BP);
1426       removeNotPreservedAnalysis(BP);
1427       recordAvailableAnalysis(BP);
1428       removeDeadPasses(BP, BB.getName(), ON_BASICBLOCK_MSG);
1429     }
1430   }
1431
1432   return doFinalization(F) || Changed;
1433 }
1434
1435 // Implement doInitialization and doFinalization
1436 bool BBPassManager::doInitialization(Module &M) {
1437   bool Changed = false;
1438
1439   for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index)
1440     Changed |= getContainedPass(Index)->doInitialization(M);
1441
1442   return Changed;
1443 }
1444
1445 bool BBPassManager::doFinalization(Module &M) {
1446   bool Changed = false;
1447
1448   for (int Index = getNumContainedPasses() - 1; Index >= 0; --Index)
1449     Changed |= getContainedPass(Index)->doFinalization(M);
1450
1451   return Changed;
1452 }
1453
1454 bool BBPassManager::doInitialization(Function &F) {
1455   bool Changed = false;
1456
1457   for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
1458     BasicBlockPass *BP = getContainedPass(Index);
1459     Changed |= BP->doInitialization(F);
1460   }
1461
1462   return Changed;
1463 }
1464
1465 bool BBPassManager::doFinalization(Function &F) {
1466   bool Changed = false;
1467
1468   for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
1469     BasicBlockPass *BP = getContainedPass(Index);
1470     Changed |= BP->doFinalization(F);
1471   }
1472
1473   return Changed;
1474 }
1475
1476
1477 //===----------------------------------------------------------------------===//
1478 // FunctionPassManager implementation
1479
1480 /// Create new Function pass manager
1481 FunctionPassManager::FunctionPassManager(Module *m) : M(m) {
1482   FPM = new FunctionPassManagerImpl();
1483   // FPM is the top level manager.
1484   FPM->setTopLevelManager(FPM);
1485
1486   AnalysisResolver *AR = new AnalysisResolver(*FPM);
1487   FPM->setResolver(AR);
1488 }
1489
1490 FunctionPassManager::~FunctionPassManager() {
1491   delete FPM;
1492 }
1493
1494 void FunctionPassManager::add(Pass *P) {
1495   FPM->add(P);
1496 }
1497
1498 /// run - Execute all of the passes scheduled for execution.  Keep
1499 /// track of whether any of the passes modifies the function, and if
1500 /// so, return true.
1501 ///
1502 bool FunctionPassManager::run(Function &F) {
1503   handleAllErrors(F.materialize(), [&](ErrorInfoBase &EIB) {
1504     report_fatal_error("Error reading bitcode file: " + EIB.message());
1505   });
1506   return FPM->run(F);
1507 }
1508
1509
1510 /// doInitialization - Run all of the initializers for the function passes.
1511 ///
1512 bool FunctionPassManager::doInitialization() {
1513   return FPM->doInitialization(*M);
1514 }
1515
1516 /// doFinalization - Run all of the finalizers for the function passes.
1517 ///
1518 bool FunctionPassManager::doFinalization() {
1519   return FPM->doFinalization(*M);
1520 }
1521
1522 //===----------------------------------------------------------------------===//
1523 // FunctionPassManagerImpl implementation
1524 //
1525 bool FunctionPassManagerImpl::doInitialization(Module &M) {
1526   bool Changed = false;
1527
1528   dumpArguments();
1529   dumpPasses();
1530
1531   for (ImmutablePass *ImPass : getImmutablePasses())
1532     Changed |= ImPass->doInitialization(M);
1533
1534   for (unsigned Index = 0; Index < getNumContainedManagers(); ++Index)
1535     Changed |= getContainedManager(Index)->doInitialization(M);
1536
1537   return Changed;
1538 }
1539
1540 bool FunctionPassManagerImpl::doFinalization(Module &M) {
1541   bool Changed = false;
1542
1543   for (int Index = getNumContainedManagers() - 1; Index >= 0; --Index)
1544     Changed |= getContainedManager(Index)->doFinalization(M);
1545
1546   for (ImmutablePass *ImPass : getImmutablePasses())
1547     Changed |= ImPass->doFinalization(M);
1548
1549   return Changed;
1550 }
1551
1552 /// cleanup - After running all passes, clean up pass manager cache.
1553 void FPPassManager::cleanup() {
1554  for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
1555     FunctionPass *FP = getContainedPass(Index);
1556     AnalysisResolver *AR = FP->getResolver();
1557     assert(AR && "Analysis Resolver is not set");
1558     AR->clearAnalysisImpls();
1559  }
1560 }
1561
1562 void FunctionPassManagerImpl::releaseMemoryOnTheFly() {
1563   if (!wasRun)
1564     return;
1565   for (unsigned Index = 0; Index < getNumContainedManagers(); ++Index) {
1566     FPPassManager *FPPM = getContainedManager(Index);
1567     for (unsigned Index = 0; Index < FPPM->getNumContainedPasses(); ++Index) {
1568       FPPM->getContainedPass(Index)->releaseMemory();
1569     }
1570   }
1571   wasRun = false;
1572 }
1573
1574 // Execute all the passes managed by this top level manager.
1575 // Return true if any function is modified by a pass.
1576 bool FunctionPassManagerImpl::run(Function &F) {
1577   bool Changed = false;
1578
1579   initializeAllAnalysisInfo();
1580   for (unsigned Index = 0; Index < getNumContainedManagers(); ++Index) {
1581     Changed |= getContainedManager(Index)->runOnFunction(F);
1582     F.getContext().yield();
1583   }
1584
1585   for (unsigned Index = 0; Index < getNumContainedManagers(); ++Index)
1586     getContainedManager(Index)->cleanup();
1587
1588   wasRun = true;
1589   return Changed;
1590 }
1591
1592 //===----------------------------------------------------------------------===//
1593 // FPPassManager implementation
1594
1595 char FPPassManager::ID = 0;
1596 /// Print passes managed by this manager
1597 void FPPassManager::dumpPassStructure(unsigned Offset) {
1598   dbgs().indent(Offset*2) << "FunctionPass Manager\n";
1599   for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
1600     FunctionPass *FP = getContainedPass(Index);
1601     FP->dumpPassStructure(Offset + 1);
1602     dumpLastUses(FP, Offset+1);
1603   }
1604 }
1605
1606
1607 /// Execute all of the passes scheduled for execution by invoking
1608 /// runOnFunction method.  Keep track of whether any of the passes modifies
1609 /// the function, and if so, return true.
1610 bool FPPassManager::runOnFunction(Function &F) {
1611   if (F.isDeclaration())
1612     return false;
1613
1614   bool Changed = false;
1615   Module &M = *F.getParent();
1616   // Collect inherited analysis from Module level pass manager.
1617   populateInheritedAnalysis(TPM->activeStack);
1618
1619   unsigned InstrCount, FunctionSize = 0;
1620   StringMap<std::pair<unsigned, unsigned>> FunctionToInstrCount;
1621   bool EmitICRemark = M.shouldEmitInstrCountChangedRemark();
1622   // Collect the initial size of the module.
1623   if (EmitICRemark) {
1624     InstrCount = initSizeRemarkInfo(M, FunctionToInstrCount);
1625     FunctionSize = F.getInstructionCount();
1626   }
1627
1628   for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
1629     FunctionPass *FP = getContainedPass(Index);
1630     bool LocalChanged = false;
1631
1632     dumpPassInfo(FP, EXECUTION_MSG, ON_FUNCTION_MSG, F.getName());
1633     dumpRequiredSet(FP);
1634
1635     initializeAnalysisImpl(FP);
1636
1637     {
1638       PassManagerPrettyStackEntry X(FP, F);
1639       TimeRegion PassTimer(getPassTimer(FP));
1640       LocalChanged |= FP->runOnFunction(F);
1641       if (EmitICRemark) {
1642         unsigned NewSize = F.getInstructionCount();
1643
1644         // Update the size of the function, emit a remark, and update the size
1645         // of the module.
1646         if (NewSize != FunctionSize) {
1647           int64_t Delta = static_cast<int64_t>(NewSize) -
1648                           static_cast<int64_t>(FunctionSize);
1649           emitInstrCountChangedRemark(FP, M, Delta, InstrCount,
1650                                       FunctionToInstrCount, &F);
1651           InstrCount = static_cast<int64_t>(InstrCount) + Delta;
1652           FunctionSize = NewSize;
1653         }
1654       }
1655     }
1656
1657     Changed |= LocalChanged;
1658     if (LocalChanged)
1659       dumpPassInfo(FP, MODIFICATION_MSG, ON_FUNCTION_MSG, F.getName());
1660     dumpPreservedSet(FP);
1661     dumpUsedSet(FP);
1662
1663     verifyPreservedAnalysis(FP);
1664     removeNotPreservedAnalysis(FP);
1665     recordAvailableAnalysis(FP);
1666     removeDeadPasses(FP, F.getName(), ON_FUNCTION_MSG);
1667   }
1668   return Changed;
1669 }
1670
1671 bool FPPassManager::runOnModule(Module &M) {
1672   bool Changed = false;
1673
1674   for (Function &F : M)
1675     Changed |= runOnFunction(F);
1676
1677   return Changed;
1678 }
1679
1680 bool FPPassManager::doInitialization(Module &M) {
1681   bool Changed = false;
1682
1683   for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index)
1684     Changed |= getContainedPass(Index)->doInitialization(M);
1685
1686   return Changed;
1687 }
1688
1689 bool FPPassManager::doFinalization(Module &M) {
1690   bool Changed = false;
1691
1692   for (int Index = getNumContainedPasses() - 1; Index >= 0; --Index)
1693     Changed |= getContainedPass(Index)->doFinalization(M);
1694
1695   return Changed;
1696 }
1697
1698 //===----------------------------------------------------------------------===//
1699 // MPPassManager implementation
1700
1701 /// Execute all of the passes scheduled for execution by invoking
1702 /// runOnModule method.  Keep track of whether any of the passes modifies
1703 /// the module, and if so, return true.
1704 bool
1705 MPPassManager::runOnModule(Module &M) {
1706   bool Changed = false;
1707
1708   // Initialize on-the-fly passes
1709   for (auto &OnTheFlyManager : OnTheFlyManagers) {
1710     FunctionPassManagerImpl *FPP = OnTheFlyManager.second;
1711     Changed |= FPP->doInitialization(M);
1712   }
1713
1714   // Initialize module passes
1715   for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index)
1716     Changed |= getContainedPass(Index)->doInitialization(M);
1717
1718   unsigned InstrCount, ModuleCount = 0;
1719   StringMap<std::pair<unsigned, unsigned>> FunctionToInstrCount;
1720   bool EmitICRemark = M.shouldEmitInstrCountChangedRemark();
1721   // Collect the initial size of the module.
1722   if (EmitICRemark) {
1723     InstrCount = initSizeRemarkInfo(M, FunctionToInstrCount);
1724     ModuleCount = InstrCount;
1725   }
1726
1727   for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
1728     ModulePass *MP = getContainedPass(Index);
1729     bool LocalChanged = false;
1730
1731     dumpPassInfo(MP, EXECUTION_MSG, ON_MODULE_MSG, M.getModuleIdentifier());
1732     dumpRequiredSet(MP);
1733
1734     initializeAnalysisImpl(MP);
1735
1736     {
1737       PassManagerPrettyStackEntry X(MP, M);
1738       TimeRegion PassTimer(getPassTimer(MP));
1739
1740       LocalChanged |= MP->runOnModule(M);
1741       if (EmitICRemark) {
1742         // Update the size of the module.
1743         ModuleCount = M.getInstructionCount();
1744         if (ModuleCount != InstrCount) {
1745           int64_t Delta = static_cast<int64_t>(ModuleCount) -
1746                           static_cast<int64_t>(InstrCount);
1747           emitInstrCountChangedRemark(MP, M, Delta, InstrCount,
1748                                       FunctionToInstrCount);
1749           InstrCount = ModuleCount;
1750         }
1751       }
1752     }
1753
1754     Changed |= LocalChanged;
1755     if (LocalChanged)
1756       dumpPassInfo(MP, MODIFICATION_MSG, ON_MODULE_MSG,
1757                    M.getModuleIdentifier());
1758     dumpPreservedSet(MP);
1759     dumpUsedSet(MP);
1760
1761     verifyPreservedAnalysis(MP);
1762     removeNotPreservedAnalysis(MP);
1763     recordAvailableAnalysis(MP);
1764     removeDeadPasses(MP, M.getModuleIdentifier(), ON_MODULE_MSG);
1765   }
1766
1767   // Finalize module passes
1768   for (int Index = getNumContainedPasses() - 1; Index >= 0; --Index)
1769     Changed |= getContainedPass(Index)->doFinalization(M);
1770
1771   // Finalize on-the-fly passes
1772   for (auto &OnTheFlyManager : OnTheFlyManagers) {
1773     FunctionPassManagerImpl *FPP = OnTheFlyManager.second;
1774     // We don't know when is the last time an on-the-fly pass is run,
1775     // so we need to releaseMemory / finalize here
1776     FPP->releaseMemoryOnTheFly();
1777     Changed |= FPP->doFinalization(M);
1778   }
1779
1780   return Changed;
1781 }
1782
1783 /// Add RequiredPass into list of lower level passes required by pass P.
1784 /// RequiredPass is run on the fly by Pass Manager when P requests it
1785 /// through getAnalysis interface.
1786 void MPPassManager::addLowerLevelRequiredPass(Pass *P, Pass *RequiredPass) {
1787   assert(P->getPotentialPassManagerType() == PMT_ModulePassManager &&
1788          "Unable to handle Pass that requires lower level Analysis pass");
1789   assert((P->getPotentialPassManagerType() <
1790           RequiredPass->getPotentialPassManagerType()) &&
1791          "Unable to handle Pass that requires lower level Analysis pass");
1792   if (!RequiredPass)
1793     return;
1794
1795   FunctionPassManagerImpl *FPP = OnTheFlyManagers[P];
1796   if (!FPP) {
1797     FPP = new FunctionPassManagerImpl();
1798     // FPP is the top level manager.
1799     FPP->setTopLevelManager(FPP);
1800
1801     OnTheFlyManagers[P] = FPP;
1802   }
1803   const PassInfo *RequiredPassPI =
1804       TPM->findAnalysisPassInfo(RequiredPass->getPassID());
1805
1806   Pass *FoundPass = nullptr;
1807   if (RequiredPassPI && RequiredPassPI->isAnalysis()) {
1808     FoundPass =
1809       ((PMTopLevelManager*)FPP)->findAnalysisPass(RequiredPass->getPassID());
1810   }
1811   if (!FoundPass) {
1812     FoundPass = RequiredPass;
1813     // This should be guaranteed to add RequiredPass to the passmanager given
1814     // that we checked for an available analysis above.
1815     FPP->add(RequiredPass);
1816   }
1817   // Register P as the last user of FoundPass or RequiredPass.
1818   SmallVector<Pass *, 1> LU;
1819   LU.push_back(FoundPass);
1820   FPP->setLastUser(LU,  P);
1821 }
1822
1823 /// Return function pass corresponding to PassInfo PI, that is
1824 /// required by module pass MP. Instantiate analysis pass, by using
1825 /// its runOnFunction() for function F.
1826 Pass* MPPassManager::getOnTheFlyPass(Pass *MP, AnalysisID PI, Function &F){
1827   FunctionPassManagerImpl *FPP = OnTheFlyManagers[MP];
1828   assert(FPP && "Unable to find on the fly pass");
1829
1830   FPP->releaseMemoryOnTheFly();
1831   FPP->run(F);
1832   return ((PMTopLevelManager*)FPP)->findAnalysisPass(PI);
1833 }
1834
1835
1836 //===----------------------------------------------------------------------===//
1837 // PassManagerImpl implementation
1838
1839 //
1840 /// run - Execute all of the passes scheduled for execution.  Keep track of
1841 /// whether any of the passes modifies the module, and if so, return true.
1842 bool PassManagerImpl::run(Module &M) {
1843   bool Changed = false;
1844
1845   dumpArguments();
1846   dumpPasses();
1847
1848   for (ImmutablePass *ImPass : getImmutablePasses())
1849     Changed |= ImPass->doInitialization(M);
1850
1851   initializeAllAnalysisInfo();
1852   for (unsigned Index = 0; Index < getNumContainedManagers(); ++Index) {
1853     Changed |= getContainedManager(Index)->runOnModule(M);
1854     M.getContext().yield();
1855   }
1856
1857   for (ImmutablePass *ImPass : getImmutablePasses())
1858     Changed |= ImPass->doFinalization(M);
1859
1860   return Changed;
1861 }
1862
1863 //===----------------------------------------------------------------------===//
1864 // PassManager implementation
1865
1866 /// Create new pass manager
1867 PassManager::PassManager() {
1868   PM = new PassManagerImpl();
1869   // PM is the top level manager
1870   PM->setTopLevelManager(PM);
1871 }
1872
1873 PassManager::~PassManager() {
1874   delete PM;
1875 }
1876
1877 void PassManager::add(Pass *P) {
1878   PM->add(P);
1879 }
1880
1881 /// run - Execute all of the passes scheduled for execution.  Keep track of
1882 /// whether any of the passes modifies the module, and if so, return true.
1883 bool PassManager::run(Module &M) {
1884   return PM->run(M);
1885 }
1886
1887 //===----------------------------------------------------------------------===//
1888 // PMStack implementation
1889 //
1890
1891 // Pop Pass Manager from the stack and clear its analysis info.
1892 void PMStack::pop() {
1893
1894   PMDataManager *Top = this->top();
1895   Top->initializeAnalysisInfo();
1896
1897   S.pop_back();
1898 }
1899
1900 // Push PM on the stack and set its top level manager.
1901 void PMStack::push(PMDataManager *PM) {
1902   assert(PM && "Unable to push. Pass Manager expected");
1903   assert(PM->getDepth()==0 && "Pass Manager depth set too early");
1904
1905   if (!this->empty()) {
1906     assert(PM->getPassManagerType() > this->top()->getPassManagerType()
1907            && "pushing bad pass manager to PMStack");
1908     PMTopLevelManager *TPM = this->top()->getTopLevelManager();
1909
1910     assert(TPM && "Unable to find top level manager");
1911     TPM->addIndirectPassManager(PM);
1912     PM->setTopLevelManager(TPM);
1913     PM->setDepth(this->top()->getDepth()+1);
1914   } else {
1915     assert((PM->getPassManagerType() == PMT_ModulePassManager
1916            || PM->getPassManagerType() == PMT_FunctionPassManager)
1917            && "pushing bad pass manager to PMStack");
1918     PM->setDepth(1);
1919   }
1920
1921   S.push_back(PM);
1922 }
1923
1924 // Dump content of the pass manager stack.
1925 LLVM_DUMP_METHOD void PMStack::dump() const {
1926   for (PMDataManager *Manager : S)
1927     dbgs() << Manager->getAsPass()->getPassName() << ' ';
1928
1929   if (!S.empty())
1930     dbgs() << '\n';
1931 }
1932
1933 /// Find appropriate Module Pass Manager in the PM Stack and
1934 /// add self into that manager.
1935 void ModulePass::assignPassManager(PMStack &PMS,
1936                                    PassManagerType PreferredType) {
1937   // Find Module Pass Manager
1938   while (!PMS.empty()) {
1939     PassManagerType TopPMType = PMS.top()->getPassManagerType();
1940     if (TopPMType == PreferredType)
1941       break; // We found desired pass manager
1942     else if (TopPMType > PMT_ModulePassManager)
1943       PMS.pop();    // Pop children pass managers
1944     else
1945       break;
1946   }
1947   assert(!PMS.empty() && "Unable to find appropriate Pass Manager");
1948   PMS.top()->add(this);
1949 }
1950
1951 /// Find appropriate Function Pass Manager or Call Graph Pass Manager
1952 /// in the PM Stack and add self into that manager.
1953 void FunctionPass::assignPassManager(PMStack &PMS,
1954                                      PassManagerType PreferredType) {
1955
1956   // Find Function Pass Manager
1957   while (!PMS.empty()) {
1958     if (PMS.top()->getPassManagerType() > PMT_FunctionPassManager)
1959       PMS.pop();
1960     else
1961       break;
1962   }
1963
1964   // Create new Function Pass Manager if needed.
1965   FPPassManager *FPP;
1966   if (PMS.top()->getPassManagerType() == PMT_FunctionPassManager) {
1967     FPP = (FPPassManager *)PMS.top();
1968   } else {
1969     assert(!PMS.empty() && "Unable to create Function Pass Manager");
1970     PMDataManager *PMD = PMS.top();
1971
1972     // [1] Create new Function Pass Manager
1973     FPP = new FPPassManager();
1974     FPP->populateInheritedAnalysis(PMS);
1975
1976     // [2] Set up new manager's top level manager
1977     PMTopLevelManager *TPM = PMD->getTopLevelManager();
1978     TPM->addIndirectPassManager(FPP);
1979
1980     // [3] Assign manager to manage this new manager. This may create
1981     // and push new managers into PMS
1982     FPP->assignPassManager(PMS, PMD->getPassManagerType());
1983
1984     // [4] Push new manager into PMS
1985     PMS.push(FPP);
1986   }
1987
1988   // Assign FPP as the manager of this pass.
1989   FPP->add(this);
1990 }
1991
1992 /// Find appropriate Basic Pass Manager or Call Graph Pass Manager
1993 /// in the PM Stack and add self into that manager.
1994 void BasicBlockPass::assignPassManager(PMStack &PMS,
1995                                        PassManagerType PreferredType) {
1996   BBPassManager *BBP;
1997
1998   // Basic Pass Manager is a leaf pass manager. It does not handle
1999   // any other pass manager.
2000   if (!PMS.empty() &&
2001       PMS.top()->getPassManagerType() == PMT_BasicBlockPassManager) {
2002     BBP = (BBPassManager *)PMS.top();
2003   } else {
2004     // If leaf manager is not Basic Block Pass manager then create new
2005     // basic Block Pass manager.
2006     assert(!PMS.empty() && "Unable to create BasicBlock Pass Manager");
2007     PMDataManager *PMD = PMS.top();
2008
2009     // [1] Create new Basic Block Manager
2010     BBP = new BBPassManager();
2011
2012     // [2] Set up new manager's top level manager
2013     // Basic Block Pass Manager does not live by itself
2014     PMTopLevelManager *TPM = PMD->getTopLevelManager();
2015     TPM->addIndirectPassManager(BBP);
2016
2017     // [3] Assign manager to manage this new manager. This may create
2018     // and push new managers into PMS
2019     BBP->assignPassManager(PMS, PreferredType);
2020
2021     // [4] Push new manager into PMS
2022     PMS.push(BBP);
2023   }
2024
2025   // Assign BBP as the manager of this pass.
2026   BBP->add(this);
2027 }
2028
2029 PassManagerBase::~PassManagerBase() {}