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Diffstat (limited to 'include/llvm/Pass.h')
| -rw-r--r-- | include/llvm/Pass.h | 380 |
1 files changed, 380 insertions, 0 deletions
diff --git a/include/llvm/Pass.h b/include/llvm/Pass.h new file mode 100644 index 0000000..923de65 --- /dev/null +++ b/include/llvm/Pass.h @@ -0,0 +1,380 @@ +//===- 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 effeciently 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/Support/DataTypes.h" +#include "llvm/Support/Streams.h" +#include <cassert> +#include <iosfwd> +#include <utility> +#include <vector> + +namespace llvm { + +class BasicBlock; +class Function; +class Module; +class AnalysisUsage; +class PassInfo; +class ImmutablePass; +class PMStack; +class AnalysisResolver; +class PMDataManager; + +// AnalysisID - Use the PassInfo to identify a pass... +typedef const PassInfo* AnalysisID; + +/// 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_BasicBlockPassManager, /// BBPassManager + PMT_Last +}; + +//===----------------------------------------------------------------------===// +/// 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; // Used to resolve analysis + intptr_t PassID; + + void operator=(const Pass&); // DO NOT IMPLEMENT + Pass(const Pass &); // DO NOT IMPLEMENT +public: + explicit Pass(intptr_t pid) : Resolver(0), PassID(pid) { + assert(pid && "pid cannot be 0"); + } + explicit Pass(const void *pid) : Resolver(0), PassID((intptr_t)pid) { + assert(pid && "pid cannot be 0"); + } + virtual ~Pass(); + + /// 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 const char *getPassName() const; + + /// getPassInfo - Return the PassInfo data structure that corresponds to this + /// pass... If the pass has not been registered, this will return null. + /// + const PassInfo *getPassInfo() const; + + /// 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(std::ostream &O, const Module *M) const; + void print(std::ostream *O, const Module *M) const { if (O) print(*O, M); } + void dump() const; // dump - call print(std::cerr, 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 = PMT_Unknown) {} + /// 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 { + return PMT_Unknown; + } + + // Access AnalysisResolver + inline void setResolver(AnalysisResolver *AR) { + assert (!Resolver && "Resolver is already set"); + Resolver = AR; + } + inline AnalysisResolver *getResolver() { + 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 { + // By default, no analysis results are used, all are invalidated. + } + + /// 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() {} + + /// 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); + + template<typename AnalysisClass> + static const PassInfo *getClassPassInfo() { + return lookupPassInfo(intptr_t(&AnalysisClass::ID)); + } + + // lookupPassInfo - Return the pass info object for the specified pass class, + // or null if it is not known. + static const PassInfo *lookupPassInfo(intptr_t TI); + + /// 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(const PassInfo *AnalysisID) 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(const PassInfo *PI) const; + + template<typename AnalysisType> + AnalysisType &getAnalysisID(const PassInfo *PI, Function &F); +}; + +inline std::ostream &operator<<(std::ostream &OS, const Pass &P) { + P.print(OS, 0); return OS; +} + +//===----------------------------------------------------------------------===// +/// 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: + /// runOnModule - Virtual method overriden by subclasses to process the module + /// being operated on. + virtual bool runOnModule(Module &M) = 0; + + virtual void assignPassManager(PMStack &PMS, + PassManagerType T = PMT_ModulePassManager); + + /// Return what kind of Pass Manager can manage this pass. + virtual PassManagerType getPotentialPassManagerType() const { + return PMT_ModulePassManager; + } + + explicit ModulePass(intptr_t pid) : Pass(pid) {} + explicit ModulePass(const void *pid) : Pass(pid) {} + // Force out-of-line virtual method. + virtual ~ModulePass(); +}; + + +//===----------------------------------------------------------------------===// +/// 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: + /// 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() {} + + /// ImmutablePasses are never run. + /// + bool runOnModule(Module &) { return false; } + + explicit ImmutablePass(intptr_t pid) : ModulePass(pid) {} + explicit ImmutablePass(const void *pid) + : ModulePass(pid) {} + + // Force out-of-line virtual method. + virtual ~ImmutablePass(); +}; + +//===----------------------------------------------------------------------===// +/// 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(intptr_t pid) : Pass(pid) {} + explicit FunctionPass(const void *pid) : Pass(pid) {} + + /// doInitialization - Virtual method overridden by subclasses to do + /// any necessary per-module initialization. + /// + virtual bool doInitialization(Module &) { return false; } + + /// runOnFunction - Virtual method overriden by subclasses to do the + /// per-function processing of the pass. + /// + virtual bool runOnFunction(Function &F) = 0; + + /// doFinalization - Virtual method overriden by subclasses to do any post + /// processing needed after all passes have run. + /// + virtual bool doFinalization(Module &) { return false; } + + /// runOnModule - On a module, we run this pass by initializing, + /// ronOnFunction'ing once for every function in the module, then by + /// finalizing. + /// + virtual bool runOnModule(Module &M); + + /// run - On a function, we simply initialize, run the function, then + /// finalize. + /// + bool run(Function &F); + + virtual void assignPassManager(PMStack &PMS, + PassManagerType T = PMT_FunctionPassManager); + + /// Return what kind of Pass Manager can manage this pass. + virtual PassManagerType getPotentialPassManagerType() const { + return PMT_FunctionPassManager; + } +}; + + + +//===----------------------------------------------------------------------===// +/// 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(intptr_t pid) : Pass(pid) {} + explicit BasicBlockPass(const void *pid) : Pass(pid) {} + + /// doInitialization - Virtual method overridden by subclasses to do + /// any necessary per-module initialization. + /// + virtual bool doInitialization(Module &) { return false; } + + /// doInitialization - Virtual method overridden by BasicBlockPass subclasses + /// to do any necessary per-function initialization. + /// + virtual bool doInitialization(Function &) { return false; } + + /// 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 &) { return false; } + + /// doFinalization - Virtual method overriden by subclasses to do any post + /// processing needed after all passes have run. + /// + virtual bool doFinalization(Module &) { return false; } + + + // To run this pass on a function, we simply call runOnBasicBlock once for + // each function. + // + bool runOnFunction(Function &F); + + virtual void assignPassManager(PMStack &PMS, + PassManagerType T = PMT_BasicBlockPassManager); + + /// Return what kind of Pass Manager can manage this pass. + virtual PassManagerType getPotentialPassManagerType() const { + return PMT_BasicBlockPassManager; + } +}; + +/// 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. +/// @brief This is the storage for the -time-passes option. +extern bool TimePassesIsEnabled; + +} // End llvm namespace + +// 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/PassSupport.h" +#include "llvm/PassAnalysisSupport.h" + +#endif |
