diff options
Diffstat (limited to 'clang-r353983e/include/llvm/Pass.h')
| -rw-r--r-- | clang-r353983e/include/llvm/Pass.h | 366 |
1 files changed, 366 insertions, 0 deletions
diff --git a/clang-r353983e/include/llvm/Pass.h b/clang-r353983e/include/llvm/Pass.h new file mode 100644 index 00000000..329f7eab --- /dev/null +++ b/clang-r353983e/include/llvm/Pass.h @@ -0,0 +1,366 @@ +//===- llvm/Pass.h - Base class for Passes ----------------------*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// 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; + +} // 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 |