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Diffstat (limited to 'include/llvm/CodeGen/TargetPassConfig.h')
| -rw-r--r-- | include/llvm/CodeGen/TargetPassConfig.h | 376 |
1 files changed, 376 insertions, 0 deletions
diff --git a/include/llvm/CodeGen/TargetPassConfig.h b/include/llvm/CodeGen/TargetPassConfig.h new file mode 100644 index 0000000000000..9309655a972ed --- /dev/null +++ b/include/llvm/CodeGen/TargetPassConfig.h @@ -0,0 +1,376 @@ +//===-- TargetPassConfig.h - Code Generation pass options -------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +/// Target-Independent Code Generator Pass Configuration Options pass. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_CODEGEN_TARGETPASSCONFIG_H +#define LLVM_CODEGEN_TARGETPASSCONFIG_H + +#include "llvm/Pass.h" +#include "llvm/Support/CodeGen.h" +#include <string> + +namespace llvm { + +class PassConfigImpl; +class ScheduleDAGInstrs; +class TargetMachine; +struct MachineSchedContext; + +// The old pass manager infrastructure is hidden in a legacy namespace now. +namespace legacy { +class PassManagerBase; +} +using legacy::PassManagerBase; + +/// Discriminated union of Pass ID types. +/// +/// The PassConfig API prefers dealing with IDs because they are safer and more +/// efficient. IDs decouple configuration from instantiation. This way, when a +/// pass is overriden, it isn't unnecessarily instantiated. It is also unsafe to +/// refer to a Pass pointer after adding it to a pass manager, which deletes +/// redundant pass instances. +/// +/// However, it is convient to directly instantiate target passes with +/// non-default ctors. These often don't have a registered PassInfo. Rather than +/// force all target passes to implement the pass registry boilerplate, allow +/// the PassConfig API to handle either type. +/// +/// AnalysisID is sadly char*, so PointerIntPair won't work. +class IdentifyingPassPtr { + union { + AnalysisID ID; + Pass *P; + }; + bool IsInstance; +public: + IdentifyingPassPtr() : P(nullptr), IsInstance(false) {} + IdentifyingPassPtr(AnalysisID IDPtr) : ID(IDPtr), IsInstance(false) {} + IdentifyingPassPtr(Pass *InstancePtr) : P(InstancePtr), IsInstance(true) {} + + bool isValid() const { return P; } + bool isInstance() const { return IsInstance; } + + AnalysisID getID() const { + assert(!IsInstance && "Not a Pass ID"); + return ID; + } + Pass *getInstance() const { + assert(IsInstance && "Not a Pass Instance"); + return P; + } +}; + +template <> struct isPodLike<IdentifyingPassPtr> { + static const bool value = true; +}; + +/// Target-Independent Code Generator Pass Configuration Options. +/// +/// This is an ImmutablePass solely for the purpose of exposing CodeGen options +/// to the internals of other CodeGen passes. +class TargetPassConfig : public ImmutablePass { +public: + /// Pseudo Pass IDs. These are defined within TargetPassConfig because they + /// are unregistered pass IDs. They are only useful for use with + /// TargetPassConfig APIs to identify multiple occurrences of the same pass. + /// + + /// EarlyTailDuplicate - A clone of the TailDuplicate pass that runs early + /// during codegen, on SSA form. + static char EarlyTailDuplicateID; + + /// PostRAMachineLICM - A clone of the LICM pass that runs during late machine + /// optimization after regalloc. + static char PostRAMachineLICMID; + +private: + PassManagerBase *PM; + AnalysisID StartBefore, StartAfter; + AnalysisID StopAfter; + bool Started; + bool Stopped; + bool AddingMachinePasses; + +protected: + TargetMachine *TM; + PassConfigImpl *Impl; // Internal data structures + bool Initialized; // Flagged after all passes are configured. + + // Target Pass Options + // Targets provide a default setting, user flags override. + // + bool DisableVerify; + + /// Default setting for -enable-tail-merge on this target. + bool EnableTailMerge; + +public: + TargetPassConfig(TargetMachine *tm, PassManagerBase &pm); + // Dummy constructor. + TargetPassConfig(); + + ~TargetPassConfig() override; + + static char ID; + + /// Get the right type of TargetMachine for this target. + template<typename TMC> TMC &getTM() const { + return *static_cast<TMC*>(TM); + } + + // + void setInitialized() { Initialized = true; } + + CodeGenOpt::Level getOptLevel() const; + + /// Set the StartAfter, StartBefore and StopAfter passes to allow running only + /// a portion of the normal code-gen pass sequence. + /// + /// If the StartAfter and StartBefore pass ID is zero, then compilation will + /// begin at the normal point; otherwise, clear the Started flag to indicate + /// that passes should not be added until the starting pass is seen. If the + /// Stop pass ID is zero, then compilation will continue to the end. + /// + /// This function expects that at least one of the StartAfter or the + /// StartBefore pass IDs is null. + void setStartStopPasses(AnalysisID StartBefore, AnalysisID StartAfter, + AnalysisID StopAfter) { + if (StartAfter) + assert(!StartBefore && "Start after and start before passes are given"); + this->StartBefore = StartBefore; + this->StartAfter = StartAfter; + this->StopAfter = StopAfter; + Started = (StartAfter == nullptr) && (StartBefore == nullptr); + } + + void setDisableVerify(bool Disable) { setOpt(DisableVerify, Disable); } + + bool getEnableTailMerge() const { return EnableTailMerge; } + void setEnableTailMerge(bool Enable) { setOpt(EnableTailMerge, Enable); } + + /// Allow the target to override a specific pass without overriding the pass + /// pipeline. When passes are added to the standard pipeline at the + /// point where StandardID is expected, add TargetID in its place. + void substitutePass(AnalysisID StandardID, IdentifyingPassPtr TargetID); + + /// Insert InsertedPassID pass after TargetPassID pass. + void insertPass(AnalysisID TargetPassID, IdentifyingPassPtr InsertedPassID, + bool VerifyAfter = true, bool PrintAfter = true); + + /// Allow the target to enable a specific standard pass by default. + void enablePass(AnalysisID PassID) { substitutePass(PassID, PassID); } + + /// Allow the target to disable a specific standard pass by default. + void disablePass(AnalysisID PassID) { + substitutePass(PassID, IdentifyingPassPtr()); + } + + /// Return the pass substituted for StandardID by the target. + /// If no substitution exists, return StandardID. + IdentifyingPassPtr getPassSubstitution(AnalysisID StandardID) const; + + /// Return true if the pass has been substituted by the target or + /// overridden on the command line. + bool isPassSubstitutedOrOverridden(AnalysisID ID) const; + + /// Return true if the optimized regalloc pipeline is enabled. + bool getOptimizeRegAlloc() const; + + /// Return true if shrink wrapping is enabled. + bool getEnableShrinkWrap() const; + + /// Return true if the default global register allocator is in use and + /// has not be overriden on the command line with '-regalloc=...' + bool usingDefaultRegAlloc() const; + + /// Add common target configurable passes that perform LLVM IR to IR + /// transforms following machine independent optimization. + virtual void addIRPasses(); + + /// Add passes to lower exception handling for the code generator. + void addPassesToHandleExceptions(); + + /// Add pass to prepare the LLVM IR for code generation. This should be done + /// before exception handling preparation passes. + virtual void addCodeGenPrepare(); + + /// Add common passes that perform LLVM IR to IR transforms in preparation for + /// instruction selection. + virtual void addISelPrepare(); + + /// addInstSelector - This method should install an instruction selector pass, + /// which converts from LLVM code to machine instructions. + virtual bool addInstSelector() { + return true; + } + + /// This method should install an IR translator pass, which converts from + /// LLVM code to machine instructions with possibly generic opcodes. + virtual bool addIRTranslator() { return true; } + + /// This method may be implemented by targets that want to run passes + /// immediately before the register bank selection. + virtual void addPreRegBankSelect() {} + + /// This method should install a register bank selector pass, which + /// assigns register banks to virtual registers without a register + /// class or register banks. + virtual bool addRegBankSelect() { return true; } + + /// Add the complete, standard set of LLVM CodeGen passes. + /// Fully developed targets will not generally override this. + virtual void addMachinePasses(); + + /// Create an instance of ScheduleDAGInstrs to be run within the standard + /// MachineScheduler pass for this function and target at the current + /// optimization level. + /// + /// This can also be used to plug a new MachineSchedStrategy into an instance + /// of the standard ScheduleDAGMI: + /// return new ScheduleDAGMI(C, make_unique<MyStrategy>(C), /*RemoveKillFlags=*/false) + /// + /// Return NULL to select the default (generic) machine scheduler. + virtual ScheduleDAGInstrs * + createMachineScheduler(MachineSchedContext *C) const { + return nullptr; + } + + /// Similar to createMachineScheduler but used when postRA machine scheduling + /// is enabled. + virtual ScheduleDAGInstrs * + createPostMachineScheduler(MachineSchedContext *C) const { + return nullptr; + } + + /// printAndVerify - Add a pass to dump then verify the machine function, if + /// those steps are enabled. + /// + void printAndVerify(const std::string &Banner); + + /// Add a pass to print the machine function if printing is enabled. + void addPrintPass(const std::string &Banner); + + /// Add a pass to perform basic verification of the machine function if + /// verification is enabled. + void addVerifyPass(const std::string &Banner); + +protected: + // Helper to verify the analysis is really immutable. + void setOpt(bool &Opt, bool Val); + + /// Methods with trivial inline returns are convenient points in the common + /// codegen pass pipeline where targets may insert passes. Methods with + /// out-of-line standard implementations are major CodeGen stages called by + /// addMachinePasses. Some targets may override major stages when inserting + /// passes is insufficient, but maintaining overriden stages is more work. + /// + + /// addPreISelPasses - This method should add any "last minute" LLVM->LLVM + /// passes (which are run just before instruction selector). + virtual bool addPreISel() { + return true; + } + + /// addMachineSSAOptimization - Add standard passes that optimize machine + /// instructions in SSA form. + virtual void addMachineSSAOptimization(); + + /// Add passes that optimize instruction level parallelism for out-of-order + /// targets. These passes are run while the machine code is still in SSA + /// form, so they can use MachineTraceMetrics to control their heuristics. + /// + /// All passes added here should preserve the MachineDominatorTree, + /// MachineLoopInfo, and MachineTraceMetrics analyses. + virtual bool addILPOpts() { + return false; + } + + /// This method may be implemented by targets that want to run passes + /// immediately before register allocation. + virtual void addPreRegAlloc() { } + + /// createTargetRegisterAllocator - Create the register allocator pass for + /// this target at the current optimization level. + virtual FunctionPass *createTargetRegisterAllocator(bool Optimized); + + /// addFastRegAlloc - Add the minimum set of target-independent passes that + /// are required for fast register allocation. + virtual void addFastRegAlloc(FunctionPass *RegAllocPass); + + /// addOptimizedRegAlloc - Add passes related to register allocation. + /// LLVMTargetMachine provides standard regalloc passes for most targets. + virtual void addOptimizedRegAlloc(FunctionPass *RegAllocPass); + + /// addPreRewrite - Add passes to the optimized register allocation pipeline + /// after register allocation is complete, but before virtual registers are + /// rewritten to physical registers. + /// + /// These passes must preserve VirtRegMap and LiveIntervals, and when running + /// after RABasic or RAGreedy, they should take advantage of LiveRegMatrix. + /// When these passes run, VirtRegMap contains legal physreg assignments for + /// all virtual registers. + virtual bool addPreRewrite() { + return false; + } + + /// This method may be implemented by targets that want to run passes after + /// register allocation pass pipeline but before prolog-epilog insertion. + virtual void addPostRegAlloc() { } + + /// Add passes that optimize machine instructions after register allocation. + virtual void addMachineLateOptimization(); + + /// This method may be implemented by targets that want to run passes after + /// prolog-epilog insertion and before the second instruction scheduling pass. + virtual void addPreSched2() { } + + /// addGCPasses - Add late codegen passes that analyze code for garbage + /// collection. This should return true if GC info should be printed after + /// these passes. + virtual bool addGCPasses(); + + /// Add standard basic block placement passes. + virtual void addBlockPlacement(); + + /// This pass may be implemented by targets that want to run passes + /// immediately before machine code is emitted. + virtual void addPreEmitPass() { } + + /// Utilities for targets to add passes to the pass manager. + /// + + /// Add a CodeGen pass at this point in the pipeline after checking overrides. + /// Return the pass that was added, or zero if no pass was added. + /// @p printAfter if true and adding a machine function pass add an extra + /// machine printer pass afterwards + /// @p verifyAfter if true and adding a machine function pass add an extra + /// machine verification pass afterwards. + AnalysisID addPass(AnalysisID PassID, bool verifyAfter = true, + bool printAfter = true); + + /// Add a pass to the PassManager if that pass is supposed to be run, as + /// determined by the StartAfter and StopAfter options. Takes ownership of the + /// pass. + /// @p printAfter if true and adding a machine function pass add an extra + /// machine printer pass afterwards + /// @p verifyAfter if true and adding a machine function pass add an extra + /// machine verification pass afterwards. + void addPass(Pass *P, bool verifyAfter = true, bool printAfter = true); + + /// addMachinePasses helper to create the target-selected or overriden + /// regalloc pass. + FunctionPass *createRegAllocPass(bool Optimized); +}; + +} // end namespace llvm + +#endif |