1 //===-- llvm/CodeGen/MachineModuleInfo.h ------------------------*- 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 // Collect meta information for a module. This information should be in a 11 // neutral form that can be used by different debugging and exception handling 12 // schemes. 13 // 14 // The organization of information is primarily clustered around the source 15 // compile units. The main exception is source line correspondence where 16 // inlining may interleave code from various compile units. 17 // 18 // The following information can be retrieved from the MachineModuleInfo. 19 // 20 // -- Source directories - Directories are uniqued based on their canonical 21 // string and assigned a sequential numeric ID (base 1.) 22 // -- Source files - Files are also uniqued based on their name and directory 23 // ID. A file ID is sequential number (base 1.) 24 // -- Source line correspondence - A vector of file ID, line#, column# triples. 25 // A DEBUG_LOCATION instruction is generated by the DAG Legalizer 26 // corresponding to each entry in the source line list. This allows a debug 27 // emitter to generate labels referenced by debug information tables. 28 // 29 //===----------------------------------------------------------------------===// 30 31 #ifndef LLVM_CODEGEN_MACHINEMODULEINFO_H 32 #define LLVM_CODEGEN_MACHINEMODULEINFO_H 33 34 #include "llvm/ADT/DenseMap.h" 35 #include "llvm/ADT/PointerIntPair.h" 36 #include "llvm/ADT/SmallPtrSet.h" 37 #include "llvm/ADT/SmallVector.h" 38 #include "llvm/Analysis/EHPersonalities.h" 39 #include "llvm/IR/DebugLoc.h" 40 #include "llvm/IR/Metadata.h" 41 #include "llvm/IR/ValueHandle.h" 42 #include "llvm/MC/MCContext.h" 43 #include "llvm/MC/MachineLocation.h" 44 #include "llvm/Pass.h" 45 #include "llvm/Support/DataTypes.h" 46 #include "llvm/Support/Dwarf.h" 47 48 namespace llvm { 49 50 //===----------------------------------------------------------------------===// 51 // Forward declarations. 52 class Constant; 53 class GlobalVariable; 54 class BlockAddress; 55 class MDNode; 56 class MMIAddrLabelMap; 57 class MachineBasicBlock; 58 class MachineFunction; 59 class Module; 60 class PointerType; 61 class StructType; 62 63 struct SEHHandler { 64 // Filter or finally function. Null indicates a catch-all. 65 const Function *FilterOrFinally; 66 67 // Address of block to recover at. Null for a finally handler. 68 const BlockAddress *RecoverBA; 69 }; 70 71 //===----------------------------------------------------------------------===// 72 /// LandingPadInfo - This structure is used to retain landing pad info for 73 /// the current function. 74 /// 75 struct LandingPadInfo { 76 MachineBasicBlock *LandingPadBlock; // Landing pad block. 77 SmallVector<MCSymbol *, 1> BeginLabels; // Labels prior to invoke. 78 SmallVector<MCSymbol *, 1> EndLabels; // Labels after invoke. 79 SmallVector<SEHHandler, 1> SEHHandlers; // SEH handlers active at this lpad. 80 MCSymbol *LandingPadLabel; // Label at beginning of landing pad. 81 std::vector<int> TypeIds; // List of type ids (filters negative). 82 83 explicit LandingPadInfo(MachineBasicBlock *MBB) 84 : LandingPadBlock(MBB), LandingPadLabel(nullptr) {} 85 }; 86 87 //===----------------------------------------------------------------------===// 88 /// MachineModuleInfoImpl - This class can be derived from and used by targets 89 /// to hold private target-specific information for each Module. Objects of 90 /// type are accessed/created with MMI::getInfo and destroyed when the 91 /// MachineModuleInfo is destroyed. 92 /// 93 class MachineModuleInfoImpl { 94 public: 95 typedef PointerIntPair<MCSymbol*, 1, bool> StubValueTy; 96 virtual ~MachineModuleInfoImpl(); 97 typedef std::vector<std::pair<MCSymbol*, StubValueTy> > SymbolListTy; 98 protected: 99 100 /// Return the entries from a DenseMap in a deterministic sorted orer. 101 /// Clears the map. 102 static SymbolListTy getSortedStubs(DenseMap<MCSymbol*, StubValueTy>&); 103 }; 104 105 //===----------------------------------------------------------------------===// 106 /// MachineModuleInfo - This class contains meta information specific to a 107 /// module. Queries can be made by different debugging and exception handling 108 /// schemes and reformated for specific use. 109 /// 110 class MachineModuleInfo : public ImmutablePass { 111 /// Context - This is the MCContext used for the entire code generator. 112 MCContext Context; 113 114 /// TheModule - This is the LLVM Module being worked on. 115 const Module *TheModule; 116 117 /// ObjFileMMI - This is the object-file-format-specific implementation of 118 /// MachineModuleInfoImpl, which lets targets accumulate whatever info they 119 /// want. 120 MachineModuleInfoImpl *ObjFileMMI; 121 122 /// List of moves done by a function's prolog. Used to construct frame maps 123 /// by debug and exception handling consumers. 124 std::vector<MCCFIInstruction> FrameInstructions; 125 126 /// LandingPads - List of LandingPadInfo describing the landing pad 127 /// information in the current function. 128 std::vector<LandingPadInfo> LandingPads; 129 130 /// LPadToCallSiteMap - Map a landing pad's EH symbol to the call site 131 /// indexes. 132 DenseMap<MCSymbol*, SmallVector<unsigned, 4> > LPadToCallSiteMap; 133 134 /// CallSiteMap - Map of invoke call site index values to associated begin 135 /// EH_LABEL for the current function. 136 DenseMap<MCSymbol*, unsigned> CallSiteMap; 137 138 /// CurCallSite - The current call site index being processed, if any. 0 if 139 /// none. 140 unsigned CurCallSite; 141 142 /// TypeInfos - List of C++ TypeInfo used in the current function. 143 std::vector<const GlobalValue *> TypeInfos; 144 145 /// FilterIds - List of typeids encoding filters used in the current function. 146 std::vector<unsigned> FilterIds; 147 148 /// FilterEnds - List of the indices in FilterIds corresponding to filter 149 /// terminators. 150 std::vector<unsigned> FilterEnds; 151 152 /// Personalities - Vector of all personality functions ever seen. Used to 153 /// emit common EH frames. 154 std::vector<const Function *> Personalities; 155 156 /// AddrLabelSymbols - This map keeps track of which symbol is being used for 157 /// the specified basic block's address of label. 158 MMIAddrLabelMap *AddrLabelSymbols; 159 160 bool CallsEHReturn; 161 bool CallsUnwindInit; 162 bool HasEHFunclets; 163 164 // TODO: Ideally, what we'd like is to have a switch that allows emitting 165 // synchronous (precise at call-sites only) CFA into .eh_frame. However, 166 // even under this switch, we'd like .debug_frame to be precise when using. 167 // -g. At this moment, there's no way to specify that some CFI directives 168 // go into .eh_frame only, while others go into .debug_frame only. 169 170 /// DbgInfoAvailable - True if debugging information is available 171 /// in this module. 172 bool DbgInfoAvailable; 173 174 /// UsesVAFloatArgument - True if this module calls VarArg function with 175 /// floating-point arguments. This is used to emit an undefined reference 176 /// to _fltused on Windows targets. 177 bool UsesVAFloatArgument; 178 179 /// UsesMorestackAddr - True if the module calls the __morestack function 180 /// indirectly, as is required under the large code model on x86. This is used 181 /// to emit a definition of a symbol, __morestack_addr, containing the 182 /// address. See comments in lib/Target/X86/X86FrameLowering.cpp for more 183 /// details. 184 bool UsesMorestackAddr; 185 186 EHPersonality PersonalityTypeCache; 187 188 public: 189 static char ID; // Pass identification, replacement for typeid 190 191 struct VariableDbgInfo { 192 const DILocalVariable *Var; 193 const DIExpression *Expr; 194 unsigned Slot; 195 const DILocation *Loc; 196 197 VariableDbgInfo(const DILocalVariable *Var, const DIExpression *Expr, 198 unsigned Slot, const DILocation *Loc) 199 : Var(Var), Expr(Expr), Slot(Slot), Loc(Loc) {} 200 }; 201 typedef SmallVector<VariableDbgInfo, 4> VariableDbgInfoMapTy; 202 VariableDbgInfoMapTy VariableDbgInfos; 203 204 MachineModuleInfo(); // DUMMY CONSTRUCTOR, DO NOT CALL. 205 // Real constructor. 206 MachineModuleInfo(const MCAsmInfo &MAI, const MCRegisterInfo &MRI, 207 const MCObjectFileInfo *MOFI); 208 ~MachineModuleInfo() override; 209 210 // Initialization and Finalization 211 bool doInitialization(Module &) override; 212 bool doFinalization(Module &) override; 213 214 /// EndFunction - Discard function meta information. 215 /// 216 void EndFunction(); 217 218 const MCContext &getContext() const { return Context; } 219 MCContext &getContext() { return Context; } 220 221 void setModule(const Module *M) { TheModule = M; } 222 const Module *getModule() const { return TheModule; } 223 224 /// getInfo - Keep track of various per-function pieces of information for 225 /// backends that would like to do so. 226 /// 227 template<typename Ty> 228 Ty &getObjFileInfo() { 229 if (ObjFileMMI == nullptr) 230 ObjFileMMI = new Ty(*this); 231 return *static_cast<Ty*>(ObjFileMMI); 232 } 233 234 template<typename Ty> 235 const Ty &getObjFileInfo() const { 236 return const_cast<MachineModuleInfo*>(this)->getObjFileInfo<Ty>(); 237 } 238 239 /// hasDebugInfo - Returns true if valid debug info is present. 240 /// 241 bool hasDebugInfo() const { return DbgInfoAvailable; } 242 void setDebugInfoAvailability(bool avail) { DbgInfoAvailable = avail; } 243 244 bool callsEHReturn() const { return CallsEHReturn; } 245 void setCallsEHReturn(bool b) { CallsEHReturn = b; } 246 247 bool callsUnwindInit() const { return CallsUnwindInit; } 248 void setCallsUnwindInit(bool b) { CallsUnwindInit = b; } 249 250 bool hasEHFunclets() const { return HasEHFunclets; } 251 void setHasEHFunclets(bool V) { HasEHFunclets = V; } 252 253 bool usesVAFloatArgument() const { 254 return UsesVAFloatArgument; 255 } 256 257 void setUsesVAFloatArgument(bool b) { 258 UsesVAFloatArgument = b; 259 } 260 261 bool usesMorestackAddr() const { 262 return UsesMorestackAddr; 263 } 264 265 void setUsesMorestackAddr(bool b) { 266 UsesMorestackAddr = b; 267 } 268 269 /// \brief Returns a reference to a list of cfi instructions in the current 270 /// function's prologue. Used to construct frame maps for debug and exception 271 /// handling comsumers. 272 const std::vector<MCCFIInstruction> &getFrameInstructions() const { 273 return FrameInstructions; 274 } 275 276 unsigned LLVM_ATTRIBUTE_UNUSED_RESULT 277 addFrameInst(const MCCFIInstruction &Inst) { 278 FrameInstructions.push_back(Inst); 279 return FrameInstructions.size() - 1; 280 } 281 282 /// getAddrLabelSymbol - Return the symbol to be used for the specified basic 283 /// block when its address is taken. This cannot be its normal LBB label 284 /// because the block may be accessed outside its containing function. 285 MCSymbol *getAddrLabelSymbol(const BasicBlock *BB) { 286 return getAddrLabelSymbolToEmit(BB).front(); 287 } 288 289 /// getAddrLabelSymbolToEmit - Return the symbol to be used for the specified 290 /// basic block when its address is taken. If other blocks were RAUW'd to 291 /// this one, we may have to emit them as well, return the whole set. 292 ArrayRef<MCSymbol *> getAddrLabelSymbolToEmit(const BasicBlock *BB); 293 294 /// takeDeletedSymbolsForFunction - If the specified function has had any 295 /// references to address-taken blocks generated, but the block got deleted, 296 /// return the symbol now so we can emit it. This prevents emitting a 297 /// reference to a symbol that has no definition. 298 void takeDeletedSymbolsForFunction(const Function *F, 299 std::vector<MCSymbol*> &Result); 300 301 302 //===- EH ---------------------------------------------------------------===// 303 304 /// getOrCreateLandingPadInfo - Find or create an LandingPadInfo for the 305 /// specified MachineBasicBlock. 306 LandingPadInfo &getOrCreateLandingPadInfo(MachineBasicBlock *LandingPad); 307 308 /// addInvoke - Provide the begin and end labels of an invoke style call and 309 /// associate it with a try landing pad block. 310 void addInvoke(MachineBasicBlock *LandingPad, 311 MCSymbol *BeginLabel, MCSymbol *EndLabel); 312 313 /// addLandingPad - Add a new panding pad. Returns the label ID for the 314 /// landing pad entry. 315 MCSymbol *addLandingPad(MachineBasicBlock *LandingPad); 316 317 /// addPersonality - Provide the personality function for the exception 318 /// information. 319 void addPersonality(const Function *Personality); 320 321 /// getPersonalities - Return array of personality functions ever seen. 322 const std::vector<const Function *>& getPersonalities() const { 323 return Personalities; 324 } 325 326 /// addCatchTypeInfo - Provide the catch typeinfo for a landing pad. 327 /// 328 void addCatchTypeInfo(MachineBasicBlock *LandingPad, 329 ArrayRef<const GlobalValue *> TyInfo); 330 331 /// addFilterTypeInfo - Provide the filter typeinfo for a landing pad. 332 /// 333 void addFilterTypeInfo(MachineBasicBlock *LandingPad, 334 ArrayRef<const GlobalValue *> TyInfo); 335 336 /// addCleanup - Add a cleanup action for a landing pad. 337 /// 338 void addCleanup(MachineBasicBlock *LandingPad); 339 340 void addSEHCatchHandler(MachineBasicBlock *LandingPad, const Function *Filter, 341 const BlockAddress *RecoverLabel); 342 343 void addSEHCleanupHandler(MachineBasicBlock *LandingPad, 344 const Function *Cleanup); 345 346 /// getTypeIDFor - Return the type id for the specified typeinfo. This is 347 /// function wide. 348 unsigned getTypeIDFor(const GlobalValue *TI); 349 350 /// getFilterIDFor - Return the id of the filter encoded by TyIds. This is 351 /// function wide. 352 int getFilterIDFor(std::vector<unsigned> &TyIds); 353 354 /// TidyLandingPads - Remap landing pad labels and remove any deleted landing 355 /// pads. 356 void TidyLandingPads(DenseMap<MCSymbol*, uintptr_t> *LPMap = nullptr); 357 358 /// getLandingPads - Return a reference to the landing pad info for the 359 /// current function. 360 const std::vector<LandingPadInfo> &getLandingPads() const { 361 return LandingPads; 362 } 363 364 /// setCallSiteLandingPad - Map the landing pad's EH symbol to the call 365 /// site indexes. 366 void setCallSiteLandingPad(MCSymbol *Sym, ArrayRef<unsigned> Sites); 367 368 /// getCallSiteLandingPad - Get the call site indexes for a landing pad EH 369 /// symbol. 370 SmallVectorImpl<unsigned> &getCallSiteLandingPad(MCSymbol *Sym) { 371 assert(hasCallSiteLandingPad(Sym) && 372 "missing call site number for landing pad!"); 373 return LPadToCallSiteMap[Sym]; 374 } 375 376 /// hasCallSiteLandingPad - Return true if the landing pad Eh symbol has an 377 /// associated call site. 378 bool hasCallSiteLandingPad(MCSymbol *Sym) { 379 return !LPadToCallSiteMap[Sym].empty(); 380 } 381 382 /// setCallSiteBeginLabel - Map the begin label for a call site. 383 void setCallSiteBeginLabel(MCSymbol *BeginLabel, unsigned Site) { 384 CallSiteMap[BeginLabel] = Site; 385 } 386 387 /// getCallSiteBeginLabel - Get the call site number for a begin label. 388 unsigned getCallSiteBeginLabel(MCSymbol *BeginLabel) { 389 assert(hasCallSiteBeginLabel(BeginLabel) && 390 "Missing call site number for EH_LABEL!"); 391 return CallSiteMap[BeginLabel]; 392 } 393 394 /// hasCallSiteBeginLabel - Return true if the begin label has a call site 395 /// number associated with it. 396 bool hasCallSiteBeginLabel(MCSymbol *BeginLabel) { 397 return CallSiteMap[BeginLabel] != 0; 398 } 399 400 /// setCurrentCallSite - Set the call site currently being processed. 401 void setCurrentCallSite(unsigned Site) { CurCallSite = Site; } 402 403 /// getCurrentCallSite - Get the call site currently being processed, if any. 404 /// return zero if none. 405 unsigned getCurrentCallSite() { return CurCallSite; } 406 407 /// getTypeInfos - Return a reference to the C++ typeinfo for the current 408 /// function. 409 const std::vector<const GlobalValue *> &getTypeInfos() const { 410 return TypeInfos; 411 } 412 413 /// getFilterIds - Return a reference to the typeids encoding filters used in 414 /// the current function. 415 const std::vector<unsigned> &getFilterIds() const { 416 return FilterIds; 417 } 418 419 /// setVariableDbgInfo - Collect information used to emit debugging 420 /// information of a variable. 421 void setVariableDbgInfo(const DILocalVariable *Var, const DIExpression *Expr, 422 unsigned Slot, const DILocation *Loc) { 423 VariableDbgInfos.emplace_back(Var, Expr, Slot, Loc); 424 } 425 426 VariableDbgInfoMapTy &getVariableDbgInfo() { return VariableDbgInfos; } 427 428 }; // End class MachineModuleInfo 429 430 } // End llvm namespace 431 432 #endif 433