MachineModuleInfo.cpp revision 49eb628c21b358380b76df82aa3dfe0baab4c6ec 
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#include "llvm/ADT/PointerUnion.h"
12#include "llvm/Analysis/ValueTracking.h"
13#include "llvm/CodeGen/MachineFunction.h"
14#include "llvm/CodeGen/MachineFunctionPass.h"
15#include "llvm/CodeGen/Passes.h"
16#include "llvm/Constants.h"
17#include "llvm/DerivedTypes.h"
18#include "llvm/GlobalVariable.h"
19#include "llvm/MC/MCObjectFileInfo.h"
20#include "llvm/MC/MCSymbol.h"
21#include "llvm/Module.h"
22#include "llvm/Support/Dwarf.h"
23#include "llvm/Support/ErrorHandling.h"
24using namespace llvm;
25using namespace llvm::dwarf;
26
27// Handle the Pass registration stuff necessary to use DataLayout's.
28INITIALIZE_PASS(MachineModuleInfo, "machinemoduleinfo",
29                "Machine Module Information", false, false)
30char MachineModuleInfo::ID = 0;
31
32// Out of line virtual method.
33MachineModuleInfoImpl::~MachineModuleInfoImpl() {}
34
35namespace llvm {
36class MMIAddrLabelMapCallbackPtr : CallbackVH {
37  MMIAddrLabelMap *Map;
38public:
39  MMIAddrLabelMapCallbackPtr() : Map(0) {}
40  MMIAddrLabelMapCallbackPtr(Value *V) : CallbackVH(V), Map(0) {}
41
42  void setPtr(BasicBlock *BB) {
43    ValueHandleBase::operator=(BB);
44  }
45
46  void setMap(MMIAddrLabelMap *map) { Map = map; }
47
48  virtual void deleted();
49  virtual void allUsesReplacedWith(Value *V2);
50};
51
52class MMIAddrLabelMap {
53  MCContext &Context;
54  struct AddrLabelSymEntry {
55    /// Symbols - The symbols for the label.  This is a pointer union that is
56    /// either one symbol (the common case) or a list of symbols.
57    PointerUnion<MCSymbol *, std::vector<MCSymbol*>*> Symbols;
58
59    Function *Fn;   // The containing function of the BasicBlock.
60    unsigned Index; // The index in BBCallbacks for the BasicBlock.
61  };
62
63  DenseMap<AssertingVH<BasicBlock>, AddrLabelSymEntry> AddrLabelSymbols;
64
65  /// BBCallbacks - Callbacks for the BasicBlock's that we have entries for.  We
66  /// use this so we get notified if a block is deleted or RAUWd.
67  std::vector<MMIAddrLabelMapCallbackPtr> BBCallbacks;
68
69  /// DeletedAddrLabelsNeedingEmission - This is a per-function list of symbols
70  /// whose corresponding BasicBlock got deleted.  These symbols need to be
71  /// emitted at some point in the file, so AsmPrinter emits them after the
72  /// function body.
73  DenseMap<AssertingVH<Function>, std::vector<MCSymbol*> >
74    DeletedAddrLabelsNeedingEmission;
75public:
76
77  MMIAddrLabelMap(MCContext &context) : Context(context) {}
78  ~MMIAddrLabelMap() {
79    assert(DeletedAddrLabelsNeedingEmission.empty() &&
80           "Some labels for deleted blocks never got emitted");
81
82    // Deallocate any of the 'list of symbols' case.
83    for (DenseMap<AssertingVH<BasicBlock>, AddrLabelSymEntry>::iterator
84         I = AddrLabelSymbols.begin(), E = AddrLabelSymbols.end(); I != E; ++I)
85      if (I->second.Symbols.is<std::vector<MCSymbol*>*>())
86        delete I->second.Symbols.get<std::vector<MCSymbol*>*>();
87  }
88
89  MCSymbol *getAddrLabelSymbol(BasicBlock *BB);
90  std::vector<MCSymbol*> getAddrLabelSymbolToEmit(BasicBlock *BB);
91
92  void takeDeletedSymbolsForFunction(Function *F,
93                                     std::vector<MCSymbol*> &Result);
94
95  void UpdateForDeletedBlock(BasicBlock *BB);
96  void UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New);
97};
98}
99
100MCSymbol *MMIAddrLabelMap::getAddrLabelSymbol(BasicBlock *BB) {
101  assert(BB->hasAddressTaken() &&
102         "Shouldn't get label for block without address taken");
103  AddrLabelSymEntry &Entry = AddrLabelSymbols[BB];
104
105  // If we already had an entry for this block, just return it.
106  if (!Entry.Symbols.isNull()) {
107    assert(BB->getParent() == Entry.Fn && "Parent changed");
108    if (Entry.Symbols.is<MCSymbol*>())
109      return Entry.Symbols.get<MCSymbol*>();
110    return (*Entry.Symbols.get<std::vector<MCSymbol*>*>())[0];
111  }
112
113  // Otherwise, this is a new entry, create a new symbol for it and add an
114  // entry to BBCallbacks so we can be notified if the BB is deleted or RAUWd.
115  BBCallbacks.push_back(BB);
116  BBCallbacks.back().setMap(this);
117  Entry.Index = BBCallbacks.size()-1;
118  Entry.Fn = BB->getParent();
119  MCSymbol *Result = Context.CreateTempSymbol();
120  Entry.Symbols = Result;
121  return Result;
122}
123
124std::vector<MCSymbol*>
125MMIAddrLabelMap::getAddrLabelSymbolToEmit(BasicBlock *BB) {
126  assert(BB->hasAddressTaken() &&
127         "Shouldn't get label for block without address taken");
128  AddrLabelSymEntry &Entry = AddrLabelSymbols[BB];
129
130  std::vector<MCSymbol*> Result;
131
132  // If we already had an entry for this block, just return it.
133  if (Entry.Symbols.isNull())
134    Result.push_back(getAddrLabelSymbol(BB));
135  else if (MCSymbol *Sym = Entry.Symbols.dyn_cast<MCSymbol*>())
136    Result.push_back(Sym);
137  else
138    Result = *Entry.Symbols.get<std::vector<MCSymbol*>*>();
139  return Result;
140}
141
142
143/// takeDeletedSymbolsForFunction - If we have any deleted symbols for F, return
144/// them.
145void MMIAddrLabelMap::
146takeDeletedSymbolsForFunction(Function *F, std::vector<MCSymbol*> &Result) {
147  DenseMap<AssertingVH<Function>, std::vector<MCSymbol*> >::iterator I =
148    DeletedAddrLabelsNeedingEmission.find(F);
149
150  // If there are no entries for the function, just return.
151  if (I == DeletedAddrLabelsNeedingEmission.end()) return;
152
153  // Otherwise, take the list.
154  std::swap(Result, I->second);
155  DeletedAddrLabelsNeedingEmission.erase(I);
156}
157
158
159void MMIAddrLabelMap::UpdateForDeletedBlock(BasicBlock *BB) {
160  // If the block got deleted, there is no need for the symbol.  If the symbol
161  // was already emitted, we can just forget about it, otherwise we need to
162  // queue it up for later emission when the function is output.
163  AddrLabelSymEntry Entry = AddrLabelSymbols[BB];
164  AddrLabelSymbols.erase(BB);
165  assert(!Entry.Symbols.isNull() && "Didn't have a symbol, why a callback?");
166  BBCallbacks[Entry.Index] = 0;  // Clear the callback.
167
168  assert((BB->getParent() == 0 || BB->getParent() == Entry.Fn) &&
169         "Block/parent mismatch");
170
171  // Handle both the single and the multiple symbols cases.
172  if (MCSymbol *Sym = Entry.Symbols.dyn_cast<MCSymbol*>()) {
173    if (Sym->isDefined())
174      return;
175
176    // If the block is not yet defined, we need to emit it at the end of the
177    // function.  Add the symbol to the DeletedAddrLabelsNeedingEmission list
178    // for the containing Function.  Since the block is being deleted, its
179    // parent may already be removed, we have to get the function from 'Entry'.
180    DeletedAddrLabelsNeedingEmission[Entry.Fn].push_back(Sym);
181  } else {
182    std::vector<MCSymbol*> *Syms = Entry.Symbols.get<std::vector<MCSymbol*>*>();
183
184    for (unsigned i = 0, e = Syms->size(); i != e; ++i) {
185      MCSymbol *Sym = (*Syms)[i];
186      if (Sym->isDefined()) continue;  // Ignore already emitted labels.
187
188      // If the block is not yet defined, we need to emit it at the end of the
189      // function.  Add the symbol to the DeletedAddrLabelsNeedingEmission list
190      // for the containing Function.  Since the block is being deleted, its
191      // parent may already be removed, we have to get the function from
192      // 'Entry'.
193      DeletedAddrLabelsNeedingEmission[Entry.Fn].push_back(Sym);
194    }
195
196    // The entry is deleted, free the memory associated with the symbol list.
197    delete Syms;
198  }
199}
200
201void MMIAddrLabelMap::UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New) {
202  // Get the entry for the RAUW'd block and remove it from our map.
203  AddrLabelSymEntry OldEntry = AddrLabelSymbols[Old];
204  AddrLabelSymbols.erase(Old);
205  assert(!OldEntry.Symbols.isNull() && "Didn't have a symbol, why a callback?");
206
207  AddrLabelSymEntry &NewEntry = AddrLabelSymbols[New];
208
209  // If New is not address taken, just move our symbol over to it.
210  if (NewEntry.Symbols.isNull()) {
211    BBCallbacks[OldEntry.Index].setPtr(New);    // Update the callback.
212    NewEntry = OldEntry;     // Set New's entry.
213    return;
214  }
215
216  BBCallbacks[OldEntry.Index] = 0;    // Update the callback.
217
218  // Otherwise, we need to add the old symbol to the new block's set.  If it is
219  // just a single entry, upgrade it to a symbol list.
220  if (MCSymbol *PrevSym = NewEntry.Symbols.dyn_cast<MCSymbol*>()) {
221    std::vector<MCSymbol*> *SymList = new std::vector<MCSymbol*>();
222    SymList->push_back(PrevSym);
223    NewEntry.Symbols = SymList;
224  }
225
226  std::vector<MCSymbol*> *SymList =
227    NewEntry.Symbols.get<std::vector<MCSymbol*>*>();
228
229  // If the old entry was a single symbol, add it.
230  if (MCSymbol *Sym = OldEntry.Symbols.dyn_cast<MCSymbol*>()) {
231    SymList->push_back(Sym);
232    return;
233  }
234
235  // Otherwise, concatenate the list.
236  std::vector<MCSymbol*> *Syms =OldEntry.Symbols.get<std::vector<MCSymbol*>*>();
237  SymList->insert(SymList->end(), Syms->begin(), Syms->end());
238  delete Syms;
239}
240
241
242void MMIAddrLabelMapCallbackPtr::deleted() {
243  Map->UpdateForDeletedBlock(cast<BasicBlock>(getValPtr()));
244}
245
246void MMIAddrLabelMapCallbackPtr::allUsesReplacedWith(Value *V2) {
247  Map->UpdateForRAUWBlock(cast<BasicBlock>(getValPtr()), cast<BasicBlock>(V2));
248}
249
250
251//===----------------------------------------------------------------------===//
252
253MachineModuleInfo::MachineModuleInfo(const MCAsmInfo &MAI,
254                                     const MCRegisterInfo &MRI,
255                                     const MCObjectFileInfo *MOFI)
256  : ImmutablePass(ID), Context(MAI, MRI, MOFI),
257    ObjFileMMI(0), CompactUnwindEncoding(0), CurCallSite(0), CallsEHReturn(0),
258    CallsUnwindInit(0), DbgInfoAvailable(false),
259    UsesVAFloatArgument(false) {
260  initializeMachineModuleInfoPass(*PassRegistry::getPassRegistry());
261  // Always emit some info, by default "no personality" info.
262  Personalities.push_back(NULL);
263  AddrLabelSymbols = 0;
264  TheModule = 0;
265}
266
267MachineModuleInfo::MachineModuleInfo()
268  : ImmutablePass(ID),
269    Context(*(MCAsmInfo*)0, *(MCRegisterInfo*)0, (MCObjectFileInfo*)0) {
270  llvm_unreachable("This MachineModuleInfo constructor should never be called, "
271                   "MMI should always be explicitly constructed by "
272                   "LLVMTargetMachine");
273}
274
275MachineModuleInfo::~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/// EndFunction - Discard function meta information.
285///
286void MachineModuleInfo::EndFunction() {
287  // Clean up frame info.
288  FrameMoves.clear();
289
290  // Clean up exception info.
291  LandingPads.clear();
292  CallSiteMap.clear();
293  TypeInfos.clear();
294  FilterIds.clear();
295  FilterEnds.clear();
296  CallsEHReturn = 0;
297  CallsUnwindInit = 0;
298  CompactUnwindEncoding = 0;
299  VariableDbgInfo.clear();
300}
301
302/// AnalyzeModule - Scan the module for global debug information.
303///
304void MachineModuleInfo::AnalyzeModule(const Module &M) {
305  // Insert functions in the llvm.used array (but not llvm.compiler.used) into
306  // UsedFunctions.
307  const GlobalVariable *GV = M.getGlobalVariable("llvm.used");
308  if (!GV || !GV->hasInitializer()) return;
309
310  // Should be an array of 'i8*'.
311  const ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer());
312  if (InitList == 0) return;
313
314  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
315    if (const Function *F =
316          dyn_cast<Function>(InitList->getOperand(i)->stripPointerCasts()))
317      UsedFunctions.insert(F);
318}
319
320//===- Address of Block Management ----------------------------------------===//
321
322
323/// getAddrLabelSymbol - Return the symbol to be used for the specified basic
324/// block when its address is taken.  This cannot be its normal LBB label
325/// because the block may be accessed outside its containing function.
326MCSymbol *MachineModuleInfo::getAddrLabelSymbol(const BasicBlock *BB) {
327  // Lazily create AddrLabelSymbols.
328  if (AddrLabelSymbols == 0)
329    AddrLabelSymbols = new MMIAddrLabelMap(Context);
330  return AddrLabelSymbols->getAddrLabelSymbol(const_cast<BasicBlock*>(BB));
331}
332
333/// getAddrLabelSymbolToEmit - Return the symbol to be used for the specified
334/// basic block when its address is taken.  If other blocks were RAUW'd to
335/// this one, we may have to emit them as well, return the whole set.
336std::vector<MCSymbol*> MachineModuleInfo::
337getAddrLabelSymbolToEmit(const BasicBlock *BB) {
338  // Lazily create AddrLabelSymbols.
339  if (AddrLabelSymbols == 0)
340    AddrLabelSymbols = new MMIAddrLabelMap(Context);
341 return AddrLabelSymbols->getAddrLabelSymbolToEmit(const_cast<BasicBlock*>(BB));
342}
343
344
345/// takeDeletedSymbolsForFunction - If the specified function has had any
346/// references to address-taken blocks generated, but the block got deleted,
347/// return the symbol now so we can emit it.  This prevents emitting a
348/// reference to a symbol that has no definition.
349void MachineModuleInfo::
350takeDeletedSymbolsForFunction(const Function *F,
351                              std::vector<MCSymbol*> &Result) {
352  // If no blocks have had their addresses taken, we're done.
353  if (AddrLabelSymbols == 0) return;
354  return AddrLabelSymbols->
355     takeDeletedSymbolsForFunction(const_cast<Function*>(F), Result);
356}
357
358//===- EH -----------------------------------------------------------------===//
359
360/// getOrCreateLandingPadInfo - Find or create an LandingPadInfo for the
361/// specified MachineBasicBlock.
362LandingPadInfo &MachineModuleInfo::getOrCreateLandingPadInfo
363    (MachineBasicBlock *LandingPad) {
364  unsigned N = LandingPads.size();
365  for (unsigned i = 0; i < N; ++i) {
366    LandingPadInfo &LP = LandingPads[i];
367    if (LP.LandingPadBlock == LandingPad)
368      return LP;
369  }
370
371  LandingPads.push_back(LandingPadInfo(LandingPad));
372  return LandingPads[N];
373}
374
375/// addInvoke - Provide the begin and end labels of an invoke style call and
376/// associate it with a try landing pad block.
377void MachineModuleInfo::addInvoke(MachineBasicBlock *LandingPad,
378                                  MCSymbol *BeginLabel, MCSymbol *EndLabel) {
379  LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
380  LP.BeginLabels.push_back(BeginLabel);
381  LP.EndLabels.push_back(EndLabel);
382}
383
384/// addLandingPad - Provide the label of a try LandingPad block.
385///
386MCSymbol *MachineModuleInfo::addLandingPad(MachineBasicBlock *LandingPad) {
387  MCSymbol *LandingPadLabel = Context.CreateTempSymbol();
388  LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
389  LP.LandingPadLabel = LandingPadLabel;
390  return LandingPadLabel;
391}
392
393/// addPersonality - Provide the personality function for the exception
394/// information.
395void MachineModuleInfo::addPersonality(MachineBasicBlock *LandingPad,
396                                       const Function *Personality) {
397  LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
398  LP.Personality = Personality;
399
400  for (unsigned i = 0; i < Personalities.size(); ++i)
401    if (Personalities[i] == Personality)
402      return;
403
404  // If this is the first personality we're adding go
405  // ahead and add it at the beginning.
406  if (Personalities[0] == NULL)
407    Personalities[0] = Personality;
408  else
409    Personalities.push_back(Personality);
410}
411
412/// addCatchTypeInfo - Provide the catch typeinfo for a landing pad.
413///
414void MachineModuleInfo::
415addCatchTypeInfo(MachineBasicBlock *LandingPad,
416                 ArrayRef<const GlobalVariable *> TyInfo) {
417  LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
418  for (unsigned N = TyInfo.size(); N; --N)
419    LP.TypeIds.push_back(getTypeIDFor(TyInfo[N - 1]));
420}
421
422/// addFilterTypeInfo - Provide the filter typeinfo for a landing pad.
423///
424void MachineModuleInfo::
425addFilterTypeInfo(MachineBasicBlock *LandingPad,
426                  ArrayRef<const GlobalVariable *> TyInfo) {
427  LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
428  std::vector<unsigned> IdsInFilter(TyInfo.size());
429  for (unsigned I = 0, E = TyInfo.size(); I != E; ++I)
430    IdsInFilter[I] = getTypeIDFor(TyInfo[I]);
431  LP.TypeIds.push_back(getFilterIDFor(IdsInFilter));
432}
433
434/// addCleanup - Add a cleanup action for a landing pad.
435///
436void MachineModuleInfo::addCleanup(MachineBasicBlock *LandingPad) {
437  LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
438  LP.TypeIds.push_back(0);
439}
440
441/// TidyLandingPads - Remap landing pad labels and remove any deleted landing
442/// pads.
443void MachineModuleInfo::TidyLandingPads(DenseMap<MCSymbol*, uintptr_t> *LPMap) {
444  for (unsigned i = 0; i != LandingPads.size(); ) {
445    LandingPadInfo &LandingPad = LandingPads[i];
446    if (LandingPad.LandingPadLabel &&
447        !LandingPad.LandingPadLabel->isDefined() &&
448        (!LPMap || (*LPMap)[LandingPad.LandingPadLabel] == 0))
449      LandingPad.LandingPadLabel = 0;
450
451    // Special case: we *should* emit LPs with null LP MBB. This indicates
452    // "nounwind" case.
453    if (!LandingPad.LandingPadLabel && LandingPad.LandingPadBlock) {
454      LandingPads.erase(LandingPads.begin() + i);
455      continue;
456    }
457
458    for (unsigned j = 0, e = LandingPads[i].BeginLabels.size(); j != e; ++j) {
459      MCSymbol *BeginLabel = LandingPad.BeginLabels[j];
460      MCSymbol *EndLabel = LandingPad.EndLabels[j];
461      if ((BeginLabel->isDefined() ||
462           (LPMap && (*LPMap)[BeginLabel] != 0)) &&
463          (EndLabel->isDefined() ||
464           (LPMap && (*LPMap)[EndLabel] != 0))) continue;
465
466      LandingPad.BeginLabels.erase(LandingPad.BeginLabels.begin() + j);
467      LandingPad.EndLabels.erase(LandingPad.EndLabels.begin() + j);
468      --j, --e;
469    }
470
471    // Remove landing pads with no try-ranges.
472    if (LandingPads[i].BeginLabels.empty()) {
473      LandingPads.erase(LandingPads.begin() + i);
474      continue;
475    }
476
477    // If there is no landing pad, ensure that the list of typeids is empty.
478    // If the only typeid is a cleanup, this is the same as having no typeids.
479    if (!LandingPad.LandingPadBlock ||
480        (LandingPad.TypeIds.size() == 1 && !LandingPad.TypeIds[0]))
481      LandingPad.TypeIds.clear();
482    ++i;
483  }
484}
485
486/// setCallSiteLandingPad - Map the landing pad's EH symbol to the call site
487/// indexes.
488void MachineModuleInfo::setCallSiteLandingPad(MCSymbol *Sym,
489                                              ArrayRef<unsigned> Sites) {
490  LPadToCallSiteMap[Sym].append(Sites.begin(), Sites.end());
491}
492
493/// getTypeIDFor - Return the type id for the specified typeinfo.  This is
494/// function wide.
495unsigned MachineModuleInfo::getTypeIDFor(const GlobalVariable *TI) {
496  for (unsigned i = 0, N = TypeInfos.size(); i != N; ++i)
497    if (TypeInfos[i] == TI) return i + 1;
498
499  TypeInfos.push_back(TI);
500  return TypeInfos.size();
501}
502
503/// getFilterIDFor - Return the filter id for the specified typeinfos.  This is
504/// function wide.
505int MachineModuleInfo::getFilterIDFor(std::vector<unsigned> &TyIds) {
506  // If the new filter coincides with the tail of an existing filter, then
507  // re-use the existing filter.  Folding filters more than this requires
508  // re-ordering filters and/or their elements - probably not worth it.
509  for (std::vector<unsigned>::iterator I = FilterEnds.begin(),
510       E = FilterEnds.end(); I != E; ++I) {
511    unsigned i = *I, j = TyIds.size();
512
513    while (i && j)
514      if (FilterIds[--i] != TyIds[--j])
515        goto try_next;
516
517    if (!j)
518      // The new filter coincides with range [i, end) of the existing filter.
519      return -(1 + i);
520
521try_next:;
522  }
523
524  // Add the new filter.
525  int FilterID = -(1 + FilterIds.size());
526  FilterIds.reserve(FilterIds.size() + TyIds.size() + 1);
527  FilterIds.insert(FilterIds.end(), TyIds.begin(), TyIds.end());
528  FilterEnds.push_back(FilterIds.size());
529  FilterIds.push_back(0); // terminator
530  return FilterID;
531}
532
533/// getPersonality - Return the personality function for the current function.
534const Function *MachineModuleInfo::getPersonality() const {
535  // FIXME: Until PR1414 will be fixed, we're using 1 personality function per
536  // function
537  return !LandingPads.empty() ? LandingPads[0].Personality : NULL;
538}
539
540/// getPersonalityIndex - Return unique index for current personality
541/// function. NULL/first personality function should always get zero index.
542unsigned MachineModuleInfo::getPersonalityIndex() const {
543  const Function* Personality = NULL;
544
545  // Scan landing pads. If there is at least one non-NULL personality - use it.
546  for (unsigned i = 0, e = LandingPads.size(); i != e; ++i)
547    if (LandingPads[i].Personality) {
548      Personality = LandingPads[i].Personality;
549      break;
550    }
551
552  for (unsigned i = 0, e = Personalities.size(); i < e; ++i) {
553    if (Personalities[i] == Personality)
554      return i;
555  }
556
557  // This will happen if the current personality function is
558  // in the zero index.
559  return 0;
560}
561