MachineModuleInfo.cpp revision 7569322765651f19eea0609fb082e6b267d5d2b5
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" 27using namespace llvm; 28using namespace llvm::dwarf; 29 30// Handle the Pass registration stuff necessary to use TargetData's. 31INITIALIZE_PASS(MachineModuleInfo, "machinemoduleinfo", 32 "Machine Module Information", false, false); 33char MachineModuleInfo::ID = 0; 34 35// Out of line virtual method. 36MachineModuleInfoImpl::~MachineModuleInfoImpl() {} 37 38namespace llvm { 39class MMIAddrLabelMapCallbackPtr : CallbackVH { 40 MMIAddrLabelMap *Map; 41public: 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 55class 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; 78public: 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 103MCSymbol *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 127std::vector<MCSymbol*> 128MMIAddrLabelMap::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. 148void MMIAddrLabelMap:: 149takeDeletedSymbolsForFunction(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 162void 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 204void 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 245void MMIAddrLabelMapCallbackPtr::deleted() { 246 Map->UpdateForDeletedBlock(cast<BasicBlock>(getValPtr())); 247} 248 249void MMIAddrLabelMapCallbackPtr::allUsesReplacedWith(Value *V2) { 250 Map->UpdateForRAUWBlock(cast<BasicBlock>(getValPtr()), cast<BasicBlock>(V2)); 251} 252 253 254//===----------------------------------------------------------------------===// 255 256MachineModuleInfo::MachineModuleInfo(const MCAsmInfo &MAI) 257: ImmutablePass(ID), Context(MAI), 258 ObjFileMMI(0), 259 CurCallSite(0), CallsEHReturn(0), CallsUnwindInit(0), DbgInfoAvailable(false){ 260 // Always emit some info, by default "no personality" info. 261 Personalities.push_back(NULL); 262 AddrLabelSymbols = 0; 263 TheModule = 0; 264} 265 266MachineModuleInfo::MachineModuleInfo() 267: ImmutablePass(ID), Context(*(MCAsmInfo*)0) { 268 assert(0 && "This MachineModuleInfo constructor should never be called, MMI " 269 "should always be explicitly constructed by LLVMTargetMachine"); 270 abort(); 271} 272 273MachineModuleInfo::~MachineModuleInfo() { 274 delete ObjFileMMI; 275 276 // FIXME: Why isn't doFinalization being called?? 277 //assert(AddrLabelSymbols == 0 && "doFinalization not called"); 278 delete AddrLabelSymbols; 279 AddrLabelSymbols = 0; 280} 281 282/// doInitialization - Initialize the state for a new module. 283/// 284bool MachineModuleInfo::doInitialization() { 285 assert(AddrLabelSymbols == 0 && "Improperly initialized"); 286 return false; 287} 288 289/// doFinalization - Tear down the state after completion of a module. 290/// 291bool MachineModuleInfo::doFinalization() { 292 delete AddrLabelSymbols; 293 AddrLabelSymbols = 0; 294 return false; 295} 296 297/// EndFunction - Discard function meta information. 298/// 299void MachineModuleInfo::EndFunction() { 300 // Clean up frame info. 301 FrameMoves.clear(); 302 303 // Clean up exception info. 304 LandingPads.clear(); 305 CallSiteMap.clear(); 306 TypeInfos.clear(); 307 FilterIds.clear(); 308 FilterEnds.clear(); 309 CallsEHReturn = 0; 310 CallsUnwindInit = 0; 311 VariableDbgInfo.clear(); 312} 313 314/// AnalyzeModule - Scan the module for global debug information. 315/// 316void MachineModuleInfo::AnalyzeModule(const Module &M) { 317 // Insert functions in the llvm.used array (but not llvm.compiler.used) into 318 // UsedFunctions. 319 const GlobalVariable *GV = M.getGlobalVariable("llvm.used"); 320 if (!GV || !GV->hasInitializer()) return; 321 322 // Should be an array of 'i8*'. 323 const ConstantArray *InitList = dyn_cast<ConstantArray>(GV->getInitializer()); 324 if (InitList == 0) return; 325 326 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) 327 if (const Function *F = 328 dyn_cast<Function>(InitList->getOperand(i)->stripPointerCasts())) 329 UsedFunctions.insert(F); 330} 331 332//===- Address of Block Management ----------------------------------------===// 333 334 335/// getAddrLabelSymbol - Return the symbol to be used for the specified basic 336/// block when its address is taken. This cannot be its normal LBB label 337/// because the block may be accessed outside its containing function. 338MCSymbol *MachineModuleInfo::getAddrLabelSymbol(const BasicBlock *BB) { 339 // Lazily create AddrLabelSymbols. 340 if (AddrLabelSymbols == 0) 341 AddrLabelSymbols = new MMIAddrLabelMap(Context); 342 return AddrLabelSymbols->getAddrLabelSymbol(const_cast<BasicBlock*>(BB)); 343} 344 345/// getAddrLabelSymbolToEmit - Return the symbol to be used for the specified 346/// basic block when its address is taken. If other blocks were RAUW'd to 347/// this one, we may have to emit them as well, return the whole set. 348std::vector<MCSymbol*> MachineModuleInfo:: 349getAddrLabelSymbolToEmit(const BasicBlock *BB) { 350 // Lazily create AddrLabelSymbols. 351 if (AddrLabelSymbols == 0) 352 AddrLabelSymbols = new MMIAddrLabelMap(Context); 353 return AddrLabelSymbols->getAddrLabelSymbolToEmit(const_cast<BasicBlock*>(BB)); 354} 355 356 357/// takeDeletedSymbolsForFunction - If the specified function has had any 358/// references to address-taken blocks generated, but the block got deleted, 359/// return the symbol now so we can emit it. This prevents emitting a 360/// reference to a symbol that has no definition. 361void MachineModuleInfo:: 362takeDeletedSymbolsForFunction(const Function *F, 363 std::vector<MCSymbol*> &Result) { 364 // If no blocks have had their addresses taken, we're done. 365 if (AddrLabelSymbols == 0) return; 366 return AddrLabelSymbols-> 367 takeDeletedSymbolsForFunction(const_cast<Function*>(F), Result); 368} 369 370//===- EH -----------------------------------------------------------------===// 371 372/// getOrCreateLandingPadInfo - Find or create an LandingPadInfo for the 373/// specified MachineBasicBlock. 374LandingPadInfo &MachineModuleInfo::getOrCreateLandingPadInfo 375 (MachineBasicBlock *LandingPad) { 376 unsigned N = LandingPads.size(); 377 for (unsigned i = 0; i < N; ++i) { 378 LandingPadInfo &LP = LandingPads[i]; 379 if (LP.LandingPadBlock == LandingPad) 380 return LP; 381 } 382 383 LandingPads.push_back(LandingPadInfo(LandingPad)); 384 return LandingPads[N]; 385} 386 387/// addInvoke - Provide the begin and end labels of an invoke style call and 388/// associate it with a try landing pad block. 389void MachineModuleInfo::addInvoke(MachineBasicBlock *LandingPad, 390 MCSymbol *BeginLabel, MCSymbol *EndLabel) { 391 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); 392 LP.BeginLabels.push_back(BeginLabel); 393 LP.EndLabels.push_back(EndLabel); 394} 395 396/// addLandingPad - Provide the label of a try LandingPad block. 397/// 398MCSymbol *MachineModuleInfo::addLandingPad(MachineBasicBlock *LandingPad) { 399 MCSymbol *LandingPadLabel = Context.CreateTempSymbol(); 400 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); 401 LP.LandingPadLabel = LandingPadLabel; 402 return LandingPadLabel; 403} 404 405/// addPersonality - Provide the personality function for the exception 406/// information. 407void MachineModuleInfo::addPersonality(MachineBasicBlock *LandingPad, 408 const Function *Personality) { 409 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); 410 LP.Personality = Personality; 411 412 for (unsigned i = 0; i < Personalities.size(); ++i) 413 if (Personalities[i] == Personality) 414 return; 415 416 // If this is the first personality we're adding go 417 // ahead and add it at the beginning. 418 if (Personalities[0] == NULL) 419 Personalities[0] = Personality; 420 else 421 Personalities.push_back(Personality); 422} 423 424/// addCatchTypeInfo - Provide the catch typeinfo for a landing pad. 425/// 426void MachineModuleInfo::addCatchTypeInfo(MachineBasicBlock *LandingPad, 427 std::vector<const GlobalVariable *> &TyInfo) { 428 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); 429 for (unsigned N = TyInfo.size(); N; --N) 430 LP.TypeIds.push_back(getTypeIDFor(TyInfo[N - 1])); 431} 432 433/// addFilterTypeInfo - Provide the filter typeinfo for a landing pad. 434/// 435void MachineModuleInfo::addFilterTypeInfo(MachineBasicBlock *LandingPad, 436 std::vector<const GlobalVariable *> &TyInfo) { 437 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); 438 std::vector<unsigned> IdsInFilter(TyInfo.size()); 439 for (unsigned I = 0, E = TyInfo.size(); I != E; ++I) 440 IdsInFilter[I] = getTypeIDFor(TyInfo[I]); 441 LP.TypeIds.push_back(getFilterIDFor(IdsInFilter)); 442} 443 444/// addCleanup - Add a cleanup action for a landing pad. 445/// 446void MachineModuleInfo::addCleanup(MachineBasicBlock *LandingPad) { 447 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad); 448 LP.TypeIds.push_back(0); 449} 450 451/// TidyLandingPads - Remap landing pad labels and remove any deleted landing 452/// pads. 453void MachineModuleInfo::TidyLandingPads(DenseMap<MCSymbol*, uintptr_t> *LPMap) { 454 for (unsigned i = 0; i != LandingPads.size(); ) { 455 LandingPadInfo &LandingPad = LandingPads[i]; 456 if (LandingPad.LandingPadLabel && 457 !LandingPad.LandingPadLabel->isDefined() && 458 (!LPMap || (*LPMap)[LandingPad.LandingPadLabel] == 0)) 459 LandingPad.LandingPadLabel = 0; 460 461 // Special case: we *should* emit LPs with null LP MBB. This indicates 462 // "nounwind" case. 463 if (!LandingPad.LandingPadLabel && LandingPad.LandingPadBlock) { 464 LandingPads.erase(LandingPads.begin() + i); 465 continue; 466 } 467 468 for (unsigned j = 0, e = LandingPads[i].BeginLabels.size(); j != e; ++j) { 469 MCSymbol *BeginLabel = LandingPad.BeginLabels[j]; 470 MCSymbol *EndLabel = LandingPad.EndLabels[j]; 471 if ((BeginLabel->isDefined() || 472 (LPMap && (*LPMap)[BeginLabel] != 0)) && 473 (EndLabel->isDefined() || 474 (LPMap && (*LPMap)[EndLabel] != 0))) continue; 475 476 LandingPad.BeginLabels.erase(LandingPad.BeginLabels.begin() + j); 477 LandingPad.EndLabels.erase(LandingPad.EndLabels.begin() + j); 478 --j, --e; 479 } 480 481 // Remove landing pads with no try-ranges. 482 if (LandingPads[i].BeginLabels.empty()) { 483 LandingPads.erase(LandingPads.begin() + i); 484 continue; 485 } 486 487 // If there is no landing pad, ensure that the list of typeids is empty. 488 // If the only typeid is a cleanup, this is the same as having no typeids. 489 if (!LandingPad.LandingPadBlock || 490 (LandingPad.TypeIds.size() == 1 && !LandingPad.TypeIds[0])) 491 LandingPad.TypeIds.clear(); 492 ++i; 493 } 494} 495 496/// getTypeIDFor - Return the type id for the specified typeinfo. This is 497/// function wide. 498unsigned MachineModuleInfo::getTypeIDFor(const GlobalVariable *TI) { 499 for (unsigned i = 0, N = TypeInfos.size(); i != N; ++i) 500 if (TypeInfos[i] == TI) return i + 1; 501 502 TypeInfos.push_back(TI); 503 return TypeInfos.size(); 504} 505 506/// getFilterIDFor - Return the filter id for the specified typeinfos. This is 507/// function wide. 508int MachineModuleInfo::getFilterIDFor(std::vector<unsigned> &TyIds) { 509 // If the new filter coincides with the tail of an existing filter, then 510 // re-use the existing filter. Folding filters more than this requires 511 // re-ordering filters and/or their elements - probably not worth it. 512 for (std::vector<unsigned>::iterator I = FilterEnds.begin(), 513 E = FilterEnds.end(); I != E; ++I) { 514 unsigned i = *I, j = TyIds.size(); 515 516 while (i && j) 517 if (FilterIds[--i] != TyIds[--j]) 518 goto try_next; 519 520 if (!j) 521 // The new filter coincides with range [i, end) of the existing filter. 522 return -(1 + i); 523 524try_next:; 525 } 526 527 // Add the new filter. 528 int FilterID = -(1 + FilterIds.size()); 529 FilterIds.reserve(FilterIds.size() + TyIds.size() + 1); 530 for (unsigned I = 0, N = TyIds.size(); I != N; ++I) 531 FilterIds.push_back(TyIds[I]); 532 FilterEnds.push_back(FilterIds.size()); 533 FilterIds.push_back(0); // terminator 534 return FilterID; 535} 536 537/// getPersonality - Return the personality function for the current function. 538const Function *MachineModuleInfo::getPersonality() const { 539 // FIXME: Until PR1414 will be fixed, we're using 1 personality function per 540 // function 541 return !LandingPads.empty() ? LandingPads[0].Personality : NULL; 542} 543 544/// getPersonalityIndex - Return unique index for current personality 545/// function. NULL/first personality function should always get zero index. 546unsigned MachineModuleInfo::getPersonalityIndex() const { 547 const Function* Personality = NULL; 548 549 // Scan landing pads. If there is at least one non-NULL personality - use it. 550 for (unsigned i = 0; i != LandingPads.size(); ++i) 551 if (LandingPads[i].Personality) { 552 Personality = LandingPads[i].Personality; 553 break; 554 } 555 556 for (unsigned i = 0; i < Personalities.size(); ++i) { 557 if (Personalities[i] == Personality) 558 return i; 559 } 560 561 // This will happen if the current personality function is 562 // in the zero index. 563 return 0; 564} 565 566namespace { 567 /// VariableDebugSorter - Comparison to sort the VariableDbgInfo map 568 /// by source location, to avoid depending on the arbitrary order that 569 /// instruction selection visits variables in. 570 struct VariableDebugSorter { 571 bool operator()(const MachineModuleInfo::VariableDbgInfoMapTy::value_type &A, 572 const MachineModuleInfo::VariableDbgInfoMapTy::value_type &B) 573 const { 574 if (A.second.second.getLine() != B.second.second.getLine()) 575 return A.second.second.getLine() < B.second.second.getLine(); 576 if (A.second.second.getCol() != B.second.second.getCol()) 577 return A.second.second.getCol() < B.second.second.getCol(); 578 return false; 579 } 580 }; 581} 582