1 //===- PassManager.h - Pass management infrastructure -----------*- 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 /// \file 10 /// 11 /// This header defines various interfaces for pass management in LLVM. There 12 /// is no "pass" interface in LLVM per se. Instead, an instance of any class 13 /// which supports a method to 'run' it over a unit of IR can be used as 14 /// a pass. A pass manager is generally a tool to collect a sequence of passes 15 /// which run over a particular IR construct, and run each of them in sequence 16 /// over each such construct in the containing IR construct. As there is no 17 /// containing IR construct for a Module, a manager for passes over modules 18 /// forms the base case which runs its managed passes in sequence over the 19 /// single module provided. 20 /// 21 /// The core IR library provides managers for running passes over 22 /// modules and functions. 23 /// 24 /// * FunctionPassManager can run over a Module, runs each pass over 25 /// a Function. 26 /// * ModulePassManager must be directly run, runs each pass over the Module. 27 /// 28 /// Note that the implementations of the pass managers use concept-based 29 /// polymorphism as outlined in the "Value Semantics and Concept-based 30 /// Polymorphism" talk (or its abbreviated sibling "Inheritance Is The Base 31 /// Class of Evil") by Sean Parent: 32 /// * http://github.com/sean-parent/sean-parent.github.com/wiki/Papers-and-Presentations 33 /// * http://www.youtube.com/watch?v=_BpMYeUFXv8 34 /// * http://channel9.msdn.com/Events/GoingNative/2013/Inheritance-Is-The-Base-Class-of-Evil 35 /// 36 //===----------------------------------------------------------------------===// 37 38 #include "llvm/ADT/DenseMap.h" 39 #include "llvm/ADT/polymorphic_ptr.h" 40 #include "llvm/Support/type_traits.h" 41 #include "llvm/IR/Function.h" 42 #include "llvm/IR/Module.h" 43 #include <list> 44 #include <vector> 45 46 namespace llvm { 47 48 class Module; 49 class Function; 50 51 /// \brief Implementation details of the pass manager interfaces. 52 namespace detail { 53 54 /// \brief Template for the abstract base class used to dispatch 55 /// polymorphically over pass objects. 56 template <typename T> struct PassConcept { 57 // Boiler plate necessary for the container of derived classes. 58 virtual ~PassConcept() {} 59 virtual PassConcept *clone() = 0; 60 61 /// \brief The polymorphic API which runs the pass over a given IR entity. 62 virtual bool run(T Arg) = 0; 63 }; 64 65 /// \brief A template wrapper used to implement the polymorphic API. 66 /// 67 /// Can be instantiated for any object which provides a \c run method 68 /// accepting a \c T. It requires the pass to be a copyable 69 /// object. 70 template <typename T, typename PassT> struct PassModel : PassConcept<T> { 71 PassModel(PassT Pass) : Pass(llvm_move(Pass)) {} 72 virtual PassModel *clone() { return new PassModel(Pass); } 73 virtual bool run(T Arg) { return Pass.run(Arg); } 74 PassT Pass; 75 }; 76 77 } 78 79 class AnalysisManager; 80 81 class ModulePassManager { 82 public: 83 ModulePassManager(Module *M, AnalysisManager *AM = 0) : M(M), AM(AM) {} 84 85 template <typename ModulePassT> void addPass(ModulePassT Pass) { 86 Passes.push_back(new ModulePassModel<ModulePassT>(llvm_move(Pass))); 87 } 88 89 void run(); 90 91 private: 92 // Pull in the concept type and model template specialized for modules. 93 typedef detail::PassConcept<Module *> ModulePassConcept; 94 template <typename PassT> 95 struct ModulePassModel : detail::PassModel<Module *, PassT> { 96 ModulePassModel(PassT Pass) : detail::PassModel<Module *, PassT>(Pass) {} 97 }; 98 99 Module *M; 100 AnalysisManager *AM; 101 std::vector<polymorphic_ptr<ModulePassConcept> > Passes; 102 }; 103 104 class FunctionPassManager { 105 public: 106 FunctionPassManager(AnalysisManager *AM = 0) : AM(AM) {} 107 108 template <typename FunctionPassT> void addPass(FunctionPassT Pass) { 109 Passes.push_back(new FunctionPassModel<FunctionPassT>(llvm_move(Pass))); 110 } 111 112 bool run(Module *M); 113 114 private: 115 // Pull in the concept type and model template specialized for functions. 116 typedef detail::PassConcept<Function *> FunctionPassConcept; 117 template <typename PassT> 118 struct FunctionPassModel : detail::PassModel<Function *, PassT> { 119 FunctionPassModel(PassT Pass) 120 : detail::PassModel<Function *, PassT>(Pass) {} 121 }; 122 123 AnalysisManager *AM; 124 std::vector<polymorphic_ptr<FunctionPassConcept> > Passes; 125 }; 126 127 128 /// \brief An analysis manager to coordinate and cache analyses run over 129 /// a module. 130 /// 131 /// The analysis manager is typically used by passes in a pass pipeline 132 /// (consisting potentially of several individual pass managers) over a module 133 /// of IR. It provides registration of available analyses, declaring 134 /// requirements on support for specific analyses, running of an specific 135 /// analysis over a specific unit of IR to compute an analysis result, and 136 /// caching of the analysis results to reuse them across multiple passes. 137 /// 138 /// It is the responsibility of callers to use the invalidation API to 139 /// invalidate analysis results when the IR they correspond to changes. The 140 /// \c ModulePassManager and \c FunctionPassManager do this automatically. 141 class AnalysisManager { 142 public: 143 AnalysisManager(Module *M) : M(M) {} 144 145 /// \brief Get the result of an analysis pass for this module. 146 /// 147 /// If there is not a valid cached result in the manager already, this will 148 /// re-run the analysis to produce a valid result. 149 /// 150 /// The module passed in must be the same module as the analysis manager was 151 /// constructed around. 152 template <typename PassT> 153 const typename PassT::Result &getResult(Module *M) { 154 assert(ModuleAnalysisPasses.count(PassT::ID()) && 155 "This analysis pass was not registered prior to being queried"); 156 157 const AnalysisResultConcept<Module> &ResultConcept = 158 getResultImpl(PassT::ID(), M); 159 typedef AnalysisResultModel<Module, typename PassT::Result> ResultModelT; 160 return static_cast<const ResultModelT &>(ResultConcept).Result; 161 } 162 163 /// \brief Get the result of an analysis pass for a function. 164 /// 165 /// If there is not a valid cached result in the manager already, this will 166 /// re-run the analysis to produce a valid result. 167 template <typename PassT> 168 const typename PassT::Result &getResult(Function *F) { 169 assert(FunctionAnalysisPasses.count(PassT::ID()) && 170 "This analysis pass was not registered prior to being queried"); 171 172 const AnalysisResultConcept<Function> &ResultConcept = 173 getResultImpl(PassT::ID(), F); 174 typedef AnalysisResultModel<Function, typename PassT::Result> ResultModelT; 175 return static_cast<const ResultModelT &>(ResultConcept).Result; 176 } 177 178 /// \brief Register an analysis pass with the manager. 179 /// 180 /// This provides an initialized and set-up analysis pass to the 181 /// analysis 182 /// manager. Whomever is setting up analysis passes must use this to 183 /// populate 184 /// the manager with all of the analysis passes available. 185 template <typename PassT> void registerAnalysisPass(PassT Pass) { 186 registerAnalysisPassImpl<PassT>(llvm_move(Pass)); 187 } 188 189 /// \brief Invalidate a specific analysis pass for an IR module. 190 /// 191 /// Note that the analysis result can disregard invalidation. 192 template <typename PassT> void invalidate(Module *M) { 193 invalidateImpl(PassT::ID(), M); 194 } 195 196 /// \brief Invalidate a specific analysis pass for an IR function. 197 /// 198 /// Note that the analysis result can disregard invalidation. 199 template <typename PassT> void invalidate(Function *F) { 200 invalidateImpl(PassT::ID(), F); 201 } 202 203 /// \brief Invalidate analyses cached for an IR Module. 204 /// 205 /// Note that specific analysis results can disregard invalidation by 206 /// overriding their invalidate method. 207 /// 208 /// The module must be the module this analysis manager was constructed 209 /// around. 210 void invalidateAll(Module *M); 211 212 /// \brief Invalidate analyses cached for an IR Function. 213 /// 214 /// Note that specific analysis results can disregard invalidation by 215 /// overriding the invalidate method. 216 void invalidateAll(Function *F); 217 218 private: 219 /// \brief Abstract concept of an analysis result. 220 /// 221 /// This concept is parameterized over the IR unit that this result pertains 222 /// to. 223 template <typename IRUnitT> struct AnalysisResultConcept { 224 virtual ~AnalysisResultConcept() {} 225 virtual AnalysisResultConcept *clone() = 0; 226 227 /// \brief Method to try and mark a result as invalid. 228 /// 229 /// When the outer \c AnalysisManager detects a change in some underlying 230 /// unit of the IR, it will call this method on all of the results cached. 231 /// 232 /// \returns true if the result should indeed be invalidated (the default). 233 virtual bool invalidate(IRUnitT *IR) = 0; 234 }; 235 236 /// \brief Wrapper to model the analysis result concept. 237 /// 238 /// Can wrap any type which implements a suitable invalidate member and model 239 /// the AnalysisResultConcept for the AnalysisManager. 240 template <typename IRUnitT, typename ResultT> 241 struct AnalysisResultModel : AnalysisResultConcept<IRUnitT> { 242 AnalysisResultModel(ResultT Result) : Result(llvm_move(Result)) {} 243 virtual AnalysisResultModel *clone() { 244 return new AnalysisResultModel(Result); 245 } 246 247 /// \brief The model delegates to the \c ResultT method. 248 virtual bool invalidate(IRUnitT *IR) { return Result.invalidate(IR); } 249 250 ResultT Result; 251 }; 252 253 /// \brief Abstract concept of an analysis pass. 254 /// 255 /// This concept is parameterized over the IR unit that it can run over and 256 /// produce an analysis result. 257 template <typename IRUnitT> struct AnalysisPassConcept { 258 virtual ~AnalysisPassConcept() {} 259 virtual AnalysisPassConcept *clone() = 0; 260 261 /// \brief Method to run this analysis over a unit of IR. 262 /// \returns The analysis result object to be queried by users, the caller 263 /// takes ownership. 264 virtual AnalysisResultConcept<IRUnitT> *run(IRUnitT *IR) = 0; 265 }; 266 267 /// \brief Wrapper to model the analysis pass concept. 268 /// 269 /// Can wrap any type which implements a suitable \c run method. The method 270 /// must accept the IRUnitT as an argument and produce an object which can be 271 /// wrapped in a \c AnalysisResultModel. 272 template <typename PassT> 273 struct AnalysisPassModel : AnalysisPassConcept<typename PassT::IRUnitT> { 274 AnalysisPassModel(PassT Pass) : Pass(llvm_move(Pass)) {} 275 virtual AnalysisPassModel *clone() { return new AnalysisPassModel(Pass); } 276 277 // FIXME: Replace PassT::IRUnitT with type traits when we use C++11. 278 typedef typename PassT::IRUnitT IRUnitT; 279 280 // FIXME: Replace PassT::Result with type traits when we use C++11. 281 typedef AnalysisResultModel<IRUnitT, typename PassT::Result> ResultModelT; 282 283 /// \brief The model delegates to the \c PassT::run method. 284 /// 285 /// The return is wrapped in an \c AnalysisResultModel. 286 virtual ResultModelT *run(IRUnitT *IR) { 287 return new ResultModelT(Pass.run(IR)); 288 } 289 290 PassT Pass; 291 }; 292 293 294 /// \brief Get a module pass result, running the pass if necessary. 295 const AnalysisResultConcept<Module> &getResultImpl(void *PassID, Module *M); 296 297 /// \brief Get a function pass result, running the pass if necessary. 298 const AnalysisResultConcept<Function> &getResultImpl(void *PassID, 299 Function *F); 300 301 /// \brief Invalidate a module pass result. 302 void invalidateImpl(void *PassID, Module *M); 303 304 /// \brief Invalidate a function pass result. 305 void invalidateImpl(void *PassID, Function *F); 306 307 308 /// \brief Module pass specific implementation of registration. 309 template <typename PassT> 310 typename enable_if<is_same<typename PassT::IRUnitT, Module> >::type 311 registerAnalysisPassImpl(PassT Pass) { 312 assert(!ModuleAnalysisPasses.count(PassT::ID()) && 313 "Registered the same analysis pass twice!"); 314 ModuleAnalysisPasses[PassT::ID()] = 315 new AnalysisPassModel<PassT>(llvm_move(Pass)); 316 } 317 318 /// \brief Function pass specific implementation of registration. 319 template <typename PassT> 320 typename enable_if<is_same<typename PassT::IRUnitT, Function> >::type 321 registerAnalysisPassImpl(PassT Pass) { 322 assert(!FunctionAnalysisPasses.count(PassT::ID()) && 323 "Registered the same analysis pass twice!"); 324 FunctionAnalysisPasses[PassT::ID()] = 325 new AnalysisPassModel<PassT>(llvm_move(Pass)); 326 } 327 328 329 /// \brief Map type from module analysis pass ID to pass concept pointer. 330 typedef DenseMap<void *, polymorphic_ptr<AnalysisPassConcept<Module> > > 331 ModuleAnalysisPassMapT; 332 333 /// \brief Collection of module analysis passes, indexed by ID. 334 ModuleAnalysisPassMapT ModuleAnalysisPasses; 335 336 /// \brief Map type from module analysis pass ID to pass result concept pointer. 337 typedef DenseMap<void *, polymorphic_ptr<AnalysisResultConcept<Module> > > 338 ModuleAnalysisResultMapT; 339 340 /// \brief Cache of computed module analysis results for this module. 341 ModuleAnalysisResultMapT ModuleAnalysisResults; 342 343 344 /// \brief Map type from function analysis pass ID to pass concept pointer. 345 typedef DenseMap<void *, polymorphic_ptr<AnalysisPassConcept<Function> > > 346 FunctionAnalysisPassMapT; 347 348 /// \brief Collection of function analysis passes, indexed by ID. 349 FunctionAnalysisPassMapT FunctionAnalysisPasses; 350 351 /// \brief List of function analysis pass IDs and associated concept pointers. 352 /// 353 /// Requires iterators to be valid across appending new entries and arbitrary 354 /// erases. Provides both the pass ID and concept pointer such that it is 355 /// half of a bijection and provides storage for the actual result concept. 356 typedef std::list< 357 std::pair<void *, polymorphic_ptr<AnalysisResultConcept<Function> > > > 358 FunctionAnalysisResultListT; 359 360 /// \brief Map type from function pointer to our custom list type. 361 typedef DenseMap<Function *, FunctionAnalysisResultListT> FunctionAnalysisResultListMapT; 362 363 /// \brief Map from function to a list of function analysis results. 364 /// 365 /// Provides linear time removal of all analysis results for a function and 366 /// the ultimate storage for a particular cached analysis result. 367 FunctionAnalysisResultListMapT FunctionAnalysisResultLists; 368 369 /// \brief Map type from a pair of analysis ID and function pointer to an 370 /// iterator into a particular result list. 371 typedef DenseMap<std::pair<void *, Function *>, 372 FunctionAnalysisResultListT::iterator> 373 FunctionAnalysisResultMapT; 374 375 /// \brief Map from an analysis ID and function to a particular cached 376 /// analysis result. 377 FunctionAnalysisResultMapT FunctionAnalysisResults; 378 379 /// \brief Module handle for the \c AnalysisManager. 380 Module *M; 381 }; 382 383 } 384