| //===- llvm/Pass.h - Base class for Passes ----------------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines a base class that indicates that a specified class is a |
| // transformation pass implementation. |
| // |
| // Passes are designed this way so that it is possible to run passes in a cache |
| // and organizationally optimal order without having to specify it at the front |
| // end. This allows arbitrary passes to be strung together and have them |
| // executed as efficiently as possible. |
| // |
| // Passes should extend one of the classes below, depending on the guarantees |
| // that it can make about what will be modified as it is run. For example, most |
| // global optimizations should derive from FunctionPass, because they do not add |
| // or delete functions, they operate on the internals of the function. |
| // |
| // Note that this file #includes PassSupport.h and PassAnalysisSupport.h (at the |
| // bottom), so the APIs exposed by these files are also automatically available |
| // to all users of this file. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_PASS_H |
| #define LLVM_PASS_H |
| |
| #include "llvm/ADT/StringRef.h" |
| #include <string> |
| |
| namespace llvm { |
| |
| class AnalysisResolver; |
| class AnalysisUsage; |
| class BasicBlock; |
| class Function; |
| class ImmutablePass; |
| class Module; |
| class PassInfo; |
| class PMDataManager; |
| class PMStack; |
| class raw_ostream; |
| |
| // AnalysisID - Use the PassInfo to identify a pass... |
| using AnalysisID = const void *; |
| |
| /// Different types of internal pass managers. External pass managers |
| /// (PassManager and FunctionPassManager) are not represented here. |
| /// Ordering of pass manager types is important here. |
| enum PassManagerType { |
| PMT_Unknown = 0, |
| PMT_ModulePassManager = 1, ///< MPPassManager |
| PMT_CallGraphPassManager, ///< CGPassManager |
| PMT_FunctionPassManager, ///< FPPassManager |
| PMT_LoopPassManager, ///< LPPassManager |
| PMT_RegionPassManager, ///< RGPassManager |
| PMT_BasicBlockPassManager, ///< BBPassManager |
| PMT_Last |
| }; |
| |
| // Different types of passes. |
| enum PassKind { |
| PT_BasicBlock, |
| PT_Region, |
| PT_Loop, |
| PT_Function, |
| PT_CallGraphSCC, |
| PT_Module, |
| PT_PassManager |
| }; |
| |
| //===----------------------------------------------------------------------===// |
| /// Pass interface - Implemented by all 'passes'. Subclass this if you are an |
| /// interprocedural optimization or you do not fit into any of the more |
| /// constrained passes described below. |
| /// |
| class Pass { |
| AnalysisResolver *Resolver = nullptr; // Used to resolve analysis |
| const void *PassID; |
| PassKind Kind; |
| |
| public: |
| explicit Pass(PassKind K, char &pid) : PassID(&pid), Kind(K) {} |
| Pass(const Pass &) = delete; |
| Pass &operator=(const Pass &) = delete; |
| virtual ~Pass(); |
| |
| PassKind getPassKind() const { return Kind; } |
| |
| /// getPassName - Return a nice clean name for a pass. This usually |
| /// implemented in terms of the name that is registered by one of the |
| /// Registration templates, but can be overloaded directly. |
| virtual StringRef getPassName() const; |
| |
| /// getPassID - Return the PassID number that corresponds to this pass. |
| AnalysisID getPassID() const { |
| return PassID; |
| } |
| |
| /// doInitialization - Virtual method overridden by subclasses to do |
| /// any necessary initialization before any pass is run. |
| virtual bool doInitialization(Module &) { return false; } |
| |
| /// doFinalization - Virtual method overriden by subclasses to do any |
| /// necessary clean up after all passes have run. |
| virtual bool doFinalization(Module &) { return false; } |
| |
| /// print - Print out the internal state of the pass. This is called by |
| /// Analyze to print out the contents of an analysis. Otherwise it is not |
| /// necessary to implement this method. Beware that the module pointer MAY be |
| /// null. This automatically forwards to a virtual function that does not |
| /// provide the Module* in case the analysis doesn't need it it can just be |
| /// ignored. |
| virtual void print(raw_ostream &OS, const Module *M) const; |
| |
| void dump() const; // dump - Print to stderr. |
| |
| /// createPrinterPass - Get a Pass appropriate to print the IR this |
| /// pass operates on (Module, Function or MachineFunction). |
| virtual Pass *createPrinterPass(raw_ostream &OS, |
| const std::string &Banner) const = 0; |
| |
| /// Each pass is responsible for assigning a pass manager to itself. |
| /// PMS is the stack of available pass manager. |
| virtual void assignPassManager(PMStack &, |
| PassManagerType) {} |
| |
| /// Check if available pass managers are suitable for this pass or not. |
| virtual void preparePassManager(PMStack &); |
| |
| /// Return what kind of Pass Manager can manage this pass. |
| virtual PassManagerType getPotentialPassManagerType() const; |
| |
| // Access AnalysisResolver |
| void setResolver(AnalysisResolver *AR); |
| AnalysisResolver *getResolver() const { return Resolver; } |
| |
| /// getAnalysisUsage - This function should be overriden by passes that need |
| /// analysis information to do their job. If a pass specifies that it uses a |
| /// particular analysis result to this function, it can then use the |
| /// getAnalysis<AnalysisType>() function, below. |
| virtual void getAnalysisUsage(AnalysisUsage &) const; |
| |
| /// releaseMemory() - This member can be implemented by a pass if it wants to |
| /// be able to release its memory when it is no longer needed. The default |
| /// behavior of passes is to hold onto memory for the entire duration of their |
| /// lifetime (which is the entire compile time). For pipelined passes, this |
| /// is not a big deal because that memory gets recycled every time the pass is |
| /// invoked on another program unit. For IP passes, it is more important to |
| /// free memory when it is unused. |
| /// |
| /// Optionally implement this function to release pass memory when it is no |
| /// longer used. |
| virtual void releaseMemory(); |
| |
| /// getAdjustedAnalysisPointer - This method is used when a pass implements |
| /// an analysis interface through multiple inheritance. If needed, it should |
| /// override this to adjust the this pointer as needed for the specified pass |
| /// info. |
| virtual void *getAdjustedAnalysisPointer(AnalysisID ID); |
| virtual ImmutablePass *getAsImmutablePass(); |
| virtual PMDataManager *getAsPMDataManager(); |
| |
| /// verifyAnalysis() - This member can be implemented by a analysis pass to |
| /// check state of analysis information. |
| virtual void verifyAnalysis() const; |
| |
| // dumpPassStructure - Implement the -debug-passes=PassStructure option |
| virtual void dumpPassStructure(unsigned Offset = 0); |
| |
| // lookupPassInfo - Return the pass info object for the specified pass class, |
| // or null if it is not known. |
| static const PassInfo *lookupPassInfo(const void *TI); |
| |
| // lookupPassInfo - Return the pass info object for the pass with the given |
| // argument string, or null if it is not known. |
| static const PassInfo *lookupPassInfo(StringRef Arg); |
| |
| // createPass - Create a object for the specified pass class, |
| // or null if it is not known. |
| static Pass *createPass(AnalysisID ID); |
| |
| /// getAnalysisIfAvailable<AnalysisType>() - Subclasses use this function to |
| /// get analysis information that might be around, for example to update it. |
| /// This is different than getAnalysis in that it can fail (if the analysis |
| /// results haven't been computed), so should only be used if you can handle |
| /// the case when the analysis is not available. This method is often used by |
| /// transformation APIs to update analysis results for a pass automatically as |
| /// the transform is performed. |
| template<typename AnalysisType> AnalysisType * |
| getAnalysisIfAvailable() const; // Defined in PassAnalysisSupport.h |
| |
| /// mustPreserveAnalysisID - This method serves the same function as |
| /// getAnalysisIfAvailable, but works if you just have an AnalysisID. This |
| /// obviously cannot give you a properly typed instance of the class if you |
| /// don't have the class name available (use getAnalysisIfAvailable if you |
| /// do), but it can tell you if you need to preserve the pass at least. |
| bool mustPreserveAnalysisID(char &AID) const; |
| |
| /// getAnalysis<AnalysisType>() - This function is used by subclasses to get |
| /// to the analysis information that they claim to use by overriding the |
| /// getAnalysisUsage function. |
| template<typename AnalysisType> |
| AnalysisType &getAnalysis() const; // Defined in PassAnalysisSupport.h |
| |
| template<typename AnalysisType> |
| AnalysisType &getAnalysis(Function &F); // Defined in PassAnalysisSupport.h |
| |
| template<typename AnalysisType> |
| AnalysisType &getAnalysisID(AnalysisID PI) const; |
| |
| template<typename AnalysisType> |
| AnalysisType &getAnalysisID(AnalysisID PI, Function &F); |
| }; |
| |
| //===----------------------------------------------------------------------===// |
| /// ModulePass class - This class is used to implement unstructured |
| /// interprocedural optimizations and analyses. ModulePasses may do anything |
| /// they want to the program. |
| /// |
| class ModulePass : public Pass { |
| public: |
| explicit ModulePass(char &pid) : Pass(PT_Module, pid) {} |
| |
| // Force out-of-line virtual method. |
| ~ModulePass() override; |
| |
| /// createPrinterPass - Get a module printer pass. |
| Pass *createPrinterPass(raw_ostream &OS, |
| const std::string &Banner) const override; |
| |
| /// runOnModule - Virtual method overriden by subclasses to process the module |
| /// being operated on. |
| virtual bool runOnModule(Module &M) = 0; |
| |
| void assignPassManager(PMStack &PMS, PassManagerType T) override; |
| |
| /// Return what kind of Pass Manager can manage this pass. |
| PassManagerType getPotentialPassManagerType() const override; |
| |
| protected: |
| /// Optional passes call this function to check whether the pass should be |
| /// skipped. This is the case when optimization bisect is over the limit. |
| bool skipModule(Module &M) const; |
| }; |
| |
| //===----------------------------------------------------------------------===// |
| /// ImmutablePass class - This class is used to provide information that does |
| /// not need to be run. This is useful for things like target information and |
| /// "basic" versions of AnalysisGroups. |
| /// |
| class ImmutablePass : public ModulePass { |
| public: |
| explicit ImmutablePass(char &pid) : ModulePass(pid) {} |
| |
| // Force out-of-line virtual method. |
| ~ImmutablePass() override; |
| |
| /// initializePass - This method may be overriden by immutable passes to allow |
| /// them to perform various initialization actions they require. This is |
| /// primarily because an ImmutablePass can "require" another ImmutablePass, |
| /// and if it does, the overloaded version of initializePass may get access to |
| /// these passes with getAnalysis<>. |
| virtual void initializePass(); |
| |
| ImmutablePass *getAsImmutablePass() override { return this; } |
| |
| /// ImmutablePasses are never run. |
| bool runOnModule(Module &) override { return false; } |
| }; |
| |
| //===----------------------------------------------------------------------===// |
| /// FunctionPass class - This class is used to implement most global |
| /// optimizations. Optimizations should subclass this class if they meet the |
| /// following constraints: |
| /// |
| /// 1. Optimizations are organized globally, i.e., a function at a time |
| /// 2. Optimizing a function does not cause the addition or removal of any |
| /// functions in the module |
| /// |
| class FunctionPass : public Pass { |
| public: |
| explicit FunctionPass(char &pid) : Pass(PT_Function, pid) {} |
| |
| /// createPrinterPass - Get a function printer pass. |
| Pass *createPrinterPass(raw_ostream &OS, |
| const std::string &Banner) const override; |
| |
| /// runOnFunction - Virtual method overriden by subclasses to do the |
| /// per-function processing of the pass. |
| virtual bool runOnFunction(Function &F) = 0; |
| |
| void assignPassManager(PMStack &PMS, PassManagerType T) override; |
| |
| /// Return what kind of Pass Manager can manage this pass. |
| PassManagerType getPotentialPassManagerType() const override; |
| |
| protected: |
| /// Optional passes call this function to check whether the pass should be |
| /// skipped. This is the case when Attribute::OptimizeNone is set or when |
| /// optimization bisect is over the limit. |
| bool skipFunction(const Function &F) const; |
| }; |
| |
| //===----------------------------------------------------------------------===// |
| /// BasicBlockPass class - This class is used to implement most local |
| /// optimizations. Optimizations should subclass this class if they |
| /// meet the following constraints: |
| /// 1. Optimizations are local, operating on either a basic block or |
| /// instruction at a time. |
| /// 2. Optimizations do not modify the CFG of the contained function, or any |
| /// other basic block in the function. |
| /// 3. Optimizations conform to all of the constraints of FunctionPasses. |
| /// |
| class BasicBlockPass : public Pass { |
| public: |
| explicit BasicBlockPass(char &pid) : Pass(PT_BasicBlock, pid) {} |
| |
| /// createPrinterPass - Get a basic block printer pass. |
| Pass *createPrinterPass(raw_ostream &OS, |
| const std::string &Banner) const override; |
| |
| using llvm::Pass::doInitialization; |
| using llvm::Pass::doFinalization; |
| |
| /// doInitialization - Virtual method overridden by BasicBlockPass subclasses |
| /// to do any necessary per-function initialization. |
| virtual bool doInitialization(Function &); |
| |
| /// runOnBasicBlock - Virtual method overriden by subclasses to do the |
| /// per-basicblock processing of the pass. |
| virtual bool runOnBasicBlock(BasicBlock &BB) = 0; |
| |
| /// doFinalization - Virtual method overriden by BasicBlockPass subclasses to |
| /// do any post processing needed after all passes have run. |
| virtual bool doFinalization(Function &); |
| |
| void assignPassManager(PMStack &PMS, PassManagerType T) override; |
| |
| /// Return what kind of Pass Manager can manage this pass. |
| PassManagerType getPotentialPassManagerType() const override; |
| |
| protected: |
| /// Optional passes call this function to check whether the pass should be |
| /// skipped. This is the case when Attribute::OptimizeNone is set or when |
| /// optimization bisect is over the limit. |
| bool skipBasicBlock(const BasicBlock &BB) const; |
| }; |
| |
| /// If the user specifies the -time-passes argument on an LLVM tool command line |
| /// then the value of this boolean will be true, otherwise false. |
| /// This is the storage for the -time-passes option. |
| extern bool TimePassesIsEnabled; |
| |
| /// isFunctionInPrintList - returns true if a function should be printed via |
| // debugging options like -print-after-all/-print-before-all. |
| // Tells if the function IR should be printed by PrinterPass. |
| extern bool isFunctionInPrintList(StringRef FunctionName); |
| |
| /// forcePrintModuleIR - returns true if IR printing passes should |
| // be printing module IR (even for local-pass printers e.g. function-pass) |
| // to provide more context, as enabled by debugging option -print-module-scope |
| // Tells if IR printer should be printing module IR |
| extern bool forcePrintModuleIR(); |
| |
| } // end namespace llvm |
| |
| // Include support files that contain important APIs commonly used by Passes, |
| // but that we want to separate out to make it easier to read the header files. |
| #include "llvm/InitializePasses.h" |
| #include "llvm/PassAnalysisSupport.h" |
| #include "llvm/PassSupport.h" |
| |
| #endif // LLVM_PASS_H |