lib/CodeGen/MachineModuleInfo.cpp

   1 //===-- llvm/CodeGen/MachineModuleInfo.cpp ----------------------*- C++ -*-===//
   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 #include "llvm/CodeGen/MachineModuleInfo.h"
  11
  12 #include "llvm/Constants.h"
  13 #include "llvm/DerivedTypes.h"
  14 #include "llvm/GlobalVariable.h"
  15 #include "llvm/Module.h"
  16 #include "llvm/Analysis/ValueTracking.h"
  17 #include "llvm/CodeGen/MachineFunctionPass.h"
  18 #include "llvm/CodeGen/MachineFunction.h"
  19 #include "llvm/CodeGen/Passes.h"
  20 #include "llvm/Target/TargetInstrInfo.h"
  21 #include "llvm/Target/TargetMachine.h"
  22 #include "llvm/Target/TargetOptions.h"
  23 #include "llvm/MC/MCSymbol.h"
  24 #include "llvm/ADT/PointerUnion.h"
  25 #include "llvm/Support/Dwarf.h"
  26 #include "llvm/Support/ErrorHandling.h"
  27 using namespace llvm;
  28 using namespace llvm::dwarf;
  29
  30 // Handle the Pass registration stuff necessary to use TargetData's.
  31 INITIALIZE_PASS(MachineModuleInfo, "machinemoduleinfo",
  32                 "Machine Module Information", false, false)
  33 char MachineModuleInfo::ID = 0;
  34
  35 // Out of line virtual method.
  36 MachineModuleInfoImpl::~MachineModuleInfoImpl() {}
  37
  38 namespace llvm {
  39 class MMIAddrLabelMapCallbackPtr : CallbackVH {
  40   MMIAddrLabelMap *Map;
  41 public:
  42   MMIAddrLabelMapCallbackPtr() : Map(0) {}
  43   MMIAddrLabelMapCallbackPtr(Value *V) : CallbackVH(V), Map(0) {}
  44
  45   void setPtr(BasicBlock *BB) {
  46     ValueHandleBase::operator=(BB);
  47   }
  48
  49   void setMap(MMIAddrLabelMap *map) { Map = map; }
  50
  51   virtual void deleted();
  52   virtual void allUsesReplacedWith(Value *V2);
  53 };
  54
  55 class MMIAddrLabelMap {
  56   MCContext &Context;
  57   struct AddrLabelSymEntry {
  58     /// Symbols - The symbols for the label.  This is a pointer union that is
  59     /// either one symbol (the common case) or a list of symbols.
  60     PointerUnion<MCSymbol *, std::vector<MCSymbol*>*> Symbols;
  61
  62     Function *Fn;   // The containing function of the BasicBlock.
  63     unsigned Index; // The index in BBCallbacks for the BasicBlock.
  64   };
  65
  66   DenseMap<AssertingVH<BasicBlock>, AddrLabelSymEntry> AddrLabelSymbols;
  67
  68   /// BBCallbacks - Callbacks for the BasicBlock's that we have entries for.  We
  69   /// use this so we get notified if a block is deleted or RAUWd.
  70   std::vector<MMIAddrLabelMapCallbackPtr> BBCallbacks;
  71
  72   /// DeletedAddrLabelsNeedingEmission - This is a per-function list of symbols
  73   /// whose corresponding BasicBlock got deleted.  These symbols need to be
  74   /// emitted at some point in the file, so AsmPrinter emits them after the
  75   /// function body.
  76   DenseMap<AssertingVH<Function>, std::vector<MCSymbol*> >
  77     DeletedAddrLabelsNeedingEmission;
  78 public:
  79
  80   MMIAddrLabelMap(MCContext &context) : Context(context) {}
  81   ~MMIAddrLabelMap() {
  82     assert(DeletedAddrLabelsNeedingEmission.empty() &&
  83            "Some labels for deleted blocks never got emitted");
  84
  85     // Deallocate any of the 'list of symbols' case.
  86     for (DenseMap<AssertingVH<BasicBlock>, AddrLabelSymEntry>::iterator
  87          I = AddrLabelSymbols.begin(), E = AddrLabelSymbols.end(); I != E; ++I)
  88       if (I->second.Symbols.is<std::vector<MCSymbol*>*>())
  89         delete I->second.Symbols.get<std::vector<MCSymbol*>*>();
  90   }
  91
  92   MCSymbol *getAddrLabelSymbol(BasicBlock *BB);
  93   std::vector<MCSymbol*> getAddrLabelSymbolToEmit(BasicBlock *BB);
  94
  95   void takeDeletedSymbolsForFunction(Function *F,
  96                                      std::vector<MCSymbol*> &Result);
  97
  98   void UpdateForDeletedBlock(BasicBlock *BB);
  99   void UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New);
 100 };
 101 }
 102
 103 MCSymbol *MMIAddrLabelMap::getAddrLabelSymbol(BasicBlock *BB) {
 104   assert(BB->hasAddressTaken() &&
 105          "Shouldn't get label for block without address taken");
 106   AddrLabelSymEntry &Entry = AddrLabelSymbols[BB];
 107
 108   // If we already had an entry for this block, just return it.
 109   if (!Entry.Symbols.isNull()) {
 110     assert(BB->getParent() == Entry.Fn && "Parent changed");
 111     if (Entry.Symbols.is<MCSymbol*>())
 112       return Entry.Symbols.get<MCSymbol*>();
 113     return (*Entry.Symbols.get<std::vector<MCSymbol*>*>())[0];
 114   }
 115
 116   // Otherwise, this is a new entry, create a new symbol for it and add an
 117   // entry to BBCallbacks so we can be notified if the BB is deleted or RAUWd.
 118   BBCallbacks.push_back(BB);
 119   BBCallbacks.back().setMap(this);
 120   Entry.Index = BBCallbacks.size()-1;
 121   Entry.Fn = BB->getParent();
 122   MCSymbol *Result = Context.CreateTempSymbol();
 123   Entry.Symbols = Result;
 124   return Result;
 125 }
 126
 127 std::vector<MCSymbol*>
 128 MMIAddrLabelMap::getAddrLabelSymbolToEmit(BasicBlock *BB) {
 129   assert(BB->hasAddressTaken() &&
 130          "Shouldn't get label for block without address taken");
 131   AddrLabelSymEntry &Entry = AddrLabelSymbols[BB];
 132
 133   std::vector<MCSymbol*> Result;
 134
 135   // If we already had an entry for this block, just return it.
 136   if (Entry.Symbols.isNull())
 137     Result.push_back(getAddrLabelSymbol(BB));
 138   else if (MCSymbol *Sym = Entry.Symbols.dyn_cast<MCSymbol*>())
 139     Result.push_back(Sym);
 140   else
 141     Result = *Entry.Symbols.get<std::vector<MCSymbol*>*>();
 142   return Result;
 143 }
 144
 145
 146 /// takeDeletedSymbolsForFunction - If we have any deleted symbols for F, return
 147 /// them.
 148 void MMIAddrLabelMap::
 149 takeDeletedSymbolsForFunction(Function *F, std::vector<MCSymbol*> &Result) {
 150   DenseMap<AssertingVH<Function>, std::vector<MCSymbol*> >::iterator I =
 151     DeletedAddrLabelsNeedingEmission.find(F);
 152
 153   // If there are no entries for the function, just return.
 154   if (I == DeletedAddrLabelsNeedingEmission.end()) return;
 155
 156   // Otherwise, take the list.
 157   std::swap(Result, I->second);
 158   DeletedAddrLabelsNeedingEmission.erase(I);
 159 }
 160
 161
 162 void MMIAddrLabelMap::UpdateForDeletedBlock(BasicBlock *BB) {
 163   // If the block got deleted, there is no need for the symbol.  If the symbol
 164   // was already emitted, we can just forget about it, otherwise we need to
 165   // queue it up for later emission when the function is output.
 166   AddrLabelSymEntry Entry = AddrLabelSymbols[BB];
 167   AddrLabelSymbols.erase(BB);
 168   assert(!Entry.Symbols.isNull() && "Didn't have a symbol, why a callback?");
 169   BBCallbacks[Entry.Index] = 0;  // Clear the callback.
 170
 171   assert((BB->getParent() == 0 || BB->getParent() == Entry.Fn) &&
 172          "Block/parent mismatch");
 173
 174   // Handle both the single and the multiple symbols cases.
 175   if (MCSymbol *Sym = Entry.Symbols.dyn_cast<MCSymbol*>()) {
 176     if (Sym->isDefined())
 177       return;
 178
 179     // If the block is not yet defined, we need to emit it at the end of the
 180     // function.  Add the symbol to the DeletedAddrLabelsNeedingEmission list
 181     // for the containing Function.  Since the block is being deleted, its
 182     // parent may already be removed, we have to get the function from 'Entry'.
 183     DeletedAddrLabelsNeedingEmission[Entry.Fn].push_back(Sym);
 184   } else {
 185     std::vector<MCSymbol*> *Syms = Entry.Symbols.get<std::vector<MCSymbol*>*>();
 186
 187     for (unsigned i = 0, e = Syms->size(); i != e; ++i) {
 188       MCSymbol *Sym = (*Syms)[i];
 189       if (Sym->isDefined()) continue;  // Ignore already emitted labels.
 190
 191       // If the block is not yet defined, we need to emit it at the end of the
 192       // function.  Add the symbol to the DeletedAddrLabelsNeedingEmission list
 193       // for the containing Function.  Since the block is being deleted, its
 194       // parent may already be removed, we have to get the function from
 195       // 'Entry'.
 196       DeletedAddrLabelsNeedingEmission[Entry.Fn].push_back(Sym);
 197     }
 198
 199     // The entry is deleted, free the memory associated with the symbol list.
 200     delete Syms;
 201   }
 202 }
 203
 204 void MMIAddrLabelMap::UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New) {
 205   // Get the entry for the RAUW'd block and remove it from our map.
 206   AddrLabelSymEntry OldEntry = AddrLabelSymbols[Old];
 207   AddrLabelSymbols.erase(Old);
 208   assert(!OldEntry.Symbols.isNull() && "Didn't have a symbol, why a callback?");
 209
 210   AddrLabelSymEntry &NewEntry = AddrLabelSymbols[New];
 211
 212   // If New is not address taken, just move our symbol over to it.
 213   if (NewEntry.Symbols.isNull()) {
 214     BBCallbacks[OldEntry.Index].setPtr(New);    // Update the callback.
 215     NewEntry = OldEntry;     // Set New's entry.
 216     return;
 217   }
 218
 219   BBCallbacks[OldEntry.Index] = 0;    // Update the callback.
 220
 221   // Otherwise, we need to add the old symbol to the new block's set.  If it is
 222   // just a single entry, upgrade it to a symbol list.
 223   if (MCSymbol *PrevSym = NewEntry.Symbols.dyn_cast<MCSymbol*>()) {
 224     std::vector<MCSymbol*> *SymList = new std::vector<MCSymbol*>();
 225     SymList->push_back(PrevSym);
 226     NewEntry.Symbols = SymList;
 227   }
 228
 229   std::vector<MCSymbol*> *SymList =
 230     NewEntry.Symbols.get<std::vector<MCSymbol*>*>();
 231
 232   // If the old entry was a single symbol, add it.
 233   if (MCSymbol *Sym = OldEntry.Symbols.dyn_cast<MCSymbol*>()) {
 234     SymList->push_back(Sym);
 235     return;
 236   }
 237
 238   // Otherwise, concatenate the list.
 239   std::vector<MCSymbol*> *Syms =OldEntry.Symbols.get<std::vector<MCSymbol*>*>();
 240   SymList->insert(SymList->end(), Syms->begin(), Syms->end());
 241   delete Syms;
 242 }
 243
 244
 245 void MMIAddrLabelMapCallbackPtr::deleted() {
 246   Map->UpdateForDeletedBlock(cast<BasicBlock>(getValPtr()));
 247 }
 248
 249 void MMIAddrLabelMapCallbackPtr::allUsesReplacedWith(Value *V2) {
 250   Map->UpdateForRAUWBlock(cast<BasicBlock>(getValPtr()), cast<BasicBlock>(V2));
 251 }
 252
 253
 254 //===----------------------------------------------------------------------===//
 255
 256 MachineModuleInfo::MachineModuleInfo(const MCAsmInfo &MAI)
 257 : ImmutablePass(ID), Context(MAI),
 258   ObjFileMMI(0),
 259   CurCallSite(0), CallsEHReturn(0), CallsUnwindInit(0), DbgInfoAvailable(false),
 260   CallsExternalVAFunctionWithFloatingPointArguments(false) {
 261   initializeMachineModuleInfoPass(*PassRegistry::getPassRegistry());
 262   // Always emit some info, by default "no personality" info.
 263   Personalities.push_back(NULL);
 264   AddrLabelSymbols = 0;
 265   TheModule = 0;
 266 }
 267
 268 MachineModuleInfo::MachineModuleInfo()
 269 : ImmutablePass(ID), Context(*(MCAsmInfo*)0) {
 270   assert(0 && "This MachineModuleInfo constructor should never be called, MMI "
 271          "should always be explicitly constructed by LLVMTargetMachine");
 272   abort();
 273 }
 274
 275 MachineModuleInfo::~MachineModuleInfo() {
 276   delete ObjFileMMI;
 277
 278   // FIXME: Why isn't doFinalization being called??
 279   //assert(AddrLabelSymbols == 0 && "doFinalization not called");
 280   delete AddrLabelSymbols;
 281   AddrLabelSymbols = 0;
 282 }
 283
 284 /// doInitialization - Initialize the state for a new module.
 285 ///
 286 bool MachineModuleInfo::doInitialization() {
 287   assert(AddrLabelSymbols == 0 && "Improperly initialized");
 288   return false;
 289 }
 290
 291 /// doFinalization - Tear down the state after completion of a module.
 292 ///
 293 bool MachineModuleInfo::doFinalization() {
 294   delete AddrLabelSymbols;
 295   AddrLabelSymbols = 0;
 296   return false;
 297 }
 298
 299 /// EndFunction - Discard function meta information.
 300 ///
 301 void MachineModuleInfo::EndFunction() {
 302   // Clean up frame info.
 303   FrameMoves.clear();
 304
 305   // Clean up exception info.
 306   LandingPads.clear();
 307   CallSiteMap.clear();
 308   TypeInfos.clear();
 309   FilterIds.clear();
 310   FilterEnds.clear();
 311   CallsEHReturn = 0;
 312   CallsUnwindInit = 0;
 313   VariableDbgInfo.clear();
 314 }
 315
 316 /// AnalyzeModule - Scan the module for global debug information.
 317 ///
 318 void MachineModuleInfo::AnalyzeModule(const Module &M) {
 319   // Insert functions in the llvm.used array (but not llvm.compiler.used) into
 320   // UsedFunctions.
 321   const GlobalVariable *GV = M.getGlobalVariable("llvm.used");
 322   if (!GV || !GV->hasInitializer()) return;
 323
 324   // Should be an array of 'i8*'.
 325   const ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer());
 326   if (InitList == 0) return;
 327
 328   for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
 329     if (const Function *F =
 330           dyn_cast<Function>(InitList->getOperand(i)->stripPointerCasts()))
 331       UsedFunctions.insert(F);
 332 }
 333
 334 //===- Address of Block Management ----------------------------------------===//
 335
 336
 337 /// getAddrLabelSymbol - Return the symbol to be used for the specified basic
 338 /// block when its address is taken.  This cannot be its normal LBB label
 339 /// because the block may be accessed outside its containing function.
 340 MCSymbol *MachineModuleInfo::getAddrLabelSymbol(const BasicBlock *BB) {
 341   // Lazily create AddrLabelSymbols.
 342   if (AddrLabelSymbols == 0)
 343     AddrLabelSymbols = new MMIAddrLabelMap(Context);
 344   return AddrLabelSymbols->getAddrLabelSymbol(const_cast<BasicBlock*>(BB));
 345 }
 346
 347 /// getAddrLabelSymbolToEmit - Return the symbol to be used for the specified
 348 /// basic block when its address is taken.  If other blocks were RAUW'd to
 349 /// this one, we may have to emit them as well, return the whole set.
 350 std::vector<MCSymbol*> MachineModuleInfo::
 351 getAddrLabelSymbolToEmit(const BasicBlock *BB) {
 352   // Lazily create AddrLabelSymbols.
 353   if (AddrLabelSymbols == 0)
 354     AddrLabelSymbols = new MMIAddrLabelMap(Context);
 355  return AddrLabelSymbols->getAddrLabelSymbolToEmit(const_cast<BasicBlock*>(BB));
 356 }
 357
 358
 359 /// takeDeletedSymbolsForFunction - If the specified function has had any
 360 /// references to address-taken blocks generated, but the block got deleted,
 361 /// return the symbol now so we can emit it.  This prevents emitting a
 362 /// reference to a symbol that has no definition.
 363 void MachineModuleInfo::
 364 takeDeletedSymbolsForFunction(const Function *F,
 365                               std::vector<MCSymbol*> &Result) {
 366   // If no blocks have had their addresses taken, we're done.
 367   if (AddrLabelSymbols == 0) return;
 368   return AddrLabelSymbols->
 369      takeDeletedSymbolsForFunction(const_cast<Function*>(F), Result);
 370 }
 371
 372 //===- EH -----------------------------------------------------------------===//
 373
 374 /// getOrCreateLandingPadInfo - Find or create an LandingPadInfo for the
 375 /// specified MachineBasicBlock.
 376 LandingPadInfo &MachineModuleInfo::getOrCreateLandingPadInfo
 377     (MachineBasicBlock *LandingPad) {
 378   unsigned N = LandingPads.size();
 379   for (unsigned i = 0; i < N; ++i) {
 380     LandingPadInfo &LP = LandingPads[i];
 381     if (LP.LandingPadBlock == LandingPad)
 382       return LP;
 383   }
 384
 385   LandingPads.push_back(LandingPadInfo(LandingPad));
 386   return LandingPads[N];
 387 }
 388
 389 /// addInvoke - Provide the begin and end labels of an invoke style call and
 390 /// associate it with a try landing pad block.
 391 void MachineModuleInfo::addInvoke(MachineBasicBlock *LandingPad,
 392                                   MCSymbol *BeginLabel, MCSymbol *EndLabel) {
 393   LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
 394   LP.BeginLabels.push_back(BeginLabel);
 395   LP.EndLabels.push_back(EndLabel);
 396 }
 397
 398 /// addLandingPad - Provide the label of a try LandingPad block.
 399 ///
 400 MCSymbol *MachineModuleInfo::addLandingPad(MachineBasicBlock *LandingPad) {
 401   MCSymbol *LandingPadLabel = Context.CreateTempSymbol();
 402   LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
 403   LP.LandingPadLabel = LandingPadLabel;
 404   return LandingPadLabel;
 405 }
 406
 407 /// addPersonality - Provide the personality function for the exception
 408 /// information.
 409 void MachineModuleInfo::addPersonality(MachineBasicBlock *LandingPad,
 410                                        const Function *Personality) {
 411   LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
 412   LP.Personality = Personality;
 413
 414   for (unsigned i = 0; i < Personalities.size(); ++i)
 415     if (Personalities[i] == Personality)
 416       return;
 417
 418   // If this is the first personality we're adding go
 419   // ahead and add it at the beginning.
 420   if (Personalities[0] == NULL)
 421     Personalities[0] = Personality;
 422   else
 423     Personalities.push_back(Personality);
 424 }
 425
 426 /// addCatchTypeInfo - Provide the catch typeinfo for a landing pad.
 427 ///
 428 void MachineModuleInfo::addCatchTypeInfo(MachineBasicBlock *LandingPad,
 429                                   std::vector<const GlobalVariable *> &TyInfo) {
 430   LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
 431   for (unsigned N = TyInfo.size(); N; --N)
 432     LP.TypeIds.push_back(getTypeIDFor(TyInfo[N - 1]));
 433 }
 434
 435 /// addFilterTypeInfo - Provide the filter typeinfo for a landing pad.
 436 ///
 437 void MachineModuleInfo::addFilterTypeInfo(MachineBasicBlock *LandingPad,
 438                                   std::vector<const GlobalVariable *> &TyInfo) {
 439   LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
 440   std::vector<unsigned> IdsInFilter(TyInfo.size());
 441   for (unsigned I = 0, E = TyInfo.size(); I != E; ++I)
 442     IdsInFilter[I] = getTypeIDFor(TyInfo[I]);
 443   LP.TypeIds.push_back(getFilterIDFor(IdsInFilter));
 444 }
 445
 446 /// addCleanup - Add a cleanup action for a landing pad.
 447 ///
 448 void MachineModuleInfo::addCleanup(MachineBasicBlock *LandingPad) {
 449   LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
 450   LP.TypeIds.push_back(0);
 451 }
 452
 453 /// TidyLandingPads - Remap landing pad labels and remove any deleted landing
 454 /// pads.
 455 void MachineModuleInfo::TidyLandingPads(DenseMap<MCSymbol*, uintptr_t> *LPMap) {
 456   for (unsigned i = 0; i != LandingPads.size(); ) {
 457     LandingPadInfo &LandingPad = LandingPads[i];
 458     if (LandingPad.LandingPadLabel &&
 459         !LandingPad.LandingPadLabel->isDefined() &&
 460         (!LPMap || (*LPMap)[LandingPad.LandingPadLabel] == 0))
 461       LandingPad.LandingPadLabel = 0;
 462
 463     // Special case: we *should* emit LPs with null LP MBB. This indicates
 464     // "nounwind" case.
 465     if (!LandingPad.LandingPadLabel && LandingPad.LandingPadBlock) {
 466       LandingPads.erase(LandingPads.begin() + i);
 467       continue;
 468     }
 469
 470     for (unsigned j = 0, e = LandingPads[i].BeginLabels.size(); j != e; ++j) {
 471       MCSymbol *BeginLabel = LandingPad.BeginLabels[j];
 472       MCSymbol *EndLabel = LandingPad.EndLabels[j];
 473       if ((BeginLabel->isDefined() ||
 474            (LPMap && (*LPMap)[BeginLabel] != 0)) &&
 475           (EndLabel->isDefined() ||
 476            (LPMap && (*LPMap)[EndLabel] != 0))) continue;
 477
 478       LandingPad.BeginLabels.erase(LandingPad.BeginLabels.begin() + j);
 479       LandingPad.EndLabels.erase(LandingPad.EndLabels.begin() + j);
 480       --j, --e;
 481     }
 482
 483     // Remove landing pads with no try-ranges.
 484     if (LandingPads[i].BeginLabels.empty()) {
 485       LandingPads.erase(LandingPads.begin() + i);
 486       continue;
 487     }
 488
 489     // If there is no landing pad, ensure that the list of typeids is empty.
 490     // If the only typeid is a cleanup, this is the same as having no typeids.
 491     if (!LandingPad.LandingPadBlock ||
 492         (LandingPad.TypeIds.size() == 1 && !LandingPad.TypeIds[0]))
 493       LandingPad.TypeIds.clear();
 494     ++i;
 495   }
 496 }
 497
 498 /// getTypeIDFor - Return the type id for the specified typeinfo.  This is
 499 /// function wide.
 500 unsigned MachineModuleInfo::getTypeIDFor(const GlobalVariable *TI) {
 501   for (unsigned i = 0, N = TypeInfos.size(); i != N; ++i)
 502     if (TypeInfos[i] == TI) return i + 1;
 503
 504   TypeInfos.push_back(TI);
 505   return TypeInfos.size();
 506 }
 507
 508 /// getFilterIDFor - Return the filter id for the specified typeinfos.  This is
 509 /// function wide.
 510 int MachineModuleInfo::getFilterIDFor(std::vector<unsigned> &TyIds) {
 511   // If the new filter coincides with the tail of an existing filter, then
 512   // re-use the existing filter.  Folding filters more than this requires
 513   // re-ordering filters and/or their elements - probably not worth it.
 514   for (std::vector<unsigned>::iterator I = FilterEnds.begin(),
 515        E = FilterEnds.end(); I != E; ++I) {
 516     unsigned i = *I, j = TyIds.size();
 517
 518     while (i && j)
 519       if (FilterIds[--i] != TyIds[--j])
 520         goto try_next;
 521
 522     if (!j)
 523       // The new filter coincides with range [i, end) of the existing filter.
 524       return -(1 + i);
 525
 526 try_next:;
 527   }
 528
 529   // Add the new filter.
 530   int FilterID = -(1 + FilterIds.size());
 531   FilterIds.reserve(FilterIds.size() + TyIds.size() + 1);
 532   for (unsigned I = 0, N = TyIds.size(); I != N; ++I)
 533     FilterIds.push_back(TyIds[I]);
 534   FilterEnds.push_back(FilterIds.size());
 535   FilterIds.push_back(0); // terminator
 536   return FilterID;
 537 }
 538
 539 /// getPersonality - Return the personality function for the current function.
 540 const Function *MachineModuleInfo::getPersonality() const {
 541   // FIXME: Until PR1414 will be fixed, we're using 1 personality function per
 542   // function
 543   return !LandingPads.empty() ? LandingPads[0].Personality : NULL;
 544 }
 545
 546 /// getPersonalityIndex - Return unique index for current personality
 547 /// function. NULL/first personality function should always get zero index.
 548 unsigned MachineModuleInfo::getPersonalityIndex() const {
 549   const Function* Personality = NULL;
 550
 551   // Scan landing pads. If there is at least one non-NULL personality - use it.
 552   for (unsigned i = 0; i != LandingPads.size(); ++i)
 553     if (LandingPads[i].Personality) {
 554       Personality = LandingPads[i].Personality;
 555       break;
 556     }
 557
 558   for (unsigned i = 0; i < Personalities.size(); ++i) {
 559     if (Personalities[i] == Personality)
 560       return i;
 561   }
 562
 563   // This will happen if the current personality function is
 564   // in the zero index.
 565   return 0;
 566 }