1 //===-- MachineFunctionPass.h - Pass for MachineFunctions --------*-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 // 10 // This file defines the MachineFunctionPass class. MachineFunctionPass's are 11 // just FunctionPass's, except they operate on machine code as part of a code 12 // generator. Because they operate on machine code, not the LLVM 13 // representation, MachineFunctionPass's are not allowed to modify the LLVM 14 // representation. Due to this limitation, the MachineFunctionPass class takes 15 // care of declaring that no LLVM passes are invalidated. 16 // 17 //===----------------------------------------------------------------------===// 18 19 #ifndef LLVM_CODEGEN_MACHINEFUNCTIONPASS_H 20 #define LLVM_CODEGEN_MACHINEFUNCTIONPASS_H 21 22 #include "llvm/CodeGen/MachineFunction.h" 23 #include "llvm/Pass.h" 24 25 namespace llvm { 26 27 /// MachineFunctionPass - This class adapts the FunctionPass interface to 28 /// allow convenient creation of passes that operate on the MachineFunction 29 /// representation. Instead of overriding runOnFunction, subclasses 30 /// override runOnMachineFunction. 31 class MachineFunctionPass : public FunctionPass { 32 public: 33 bool doInitialization(Module&) override { 34 // Cache the properties info at module-init time so we don't have to 35 // construct them for every function. 36 RequiredProperties = getRequiredProperties(); 37 SetProperties = getSetProperties(); 38 ClearedProperties = getClearedProperties(); 39 return false; 40 } 41 protected: 42 explicit MachineFunctionPass(char &ID) : FunctionPass(ID) {} 43 44 /// runOnMachineFunction - This method must be overloaded to perform the 45 /// desired machine code transformation or analysis. 46 /// 47 virtual bool runOnMachineFunction(MachineFunction &MF) = 0; 48 49 /// getAnalysisUsage - Subclasses that override getAnalysisUsage 50 /// must call this. 51 /// 52 /// For MachineFunctionPasses, calling AU.preservesCFG() indicates that 53 /// the pass does not modify the MachineBasicBlock CFG. 54 /// 55 void getAnalysisUsage(AnalysisUsage &AU) const override; 56 57 virtual MachineFunctionProperties getRequiredProperties() const { 58 return MachineFunctionProperties(); 59 } 60 virtual MachineFunctionProperties getSetProperties() const { 61 return MachineFunctionProperties(); 62 } 63 virtual MachineFunctionProperties getClearedProperties() const { 64 return MachineFunctionProperties(); 65 } 66 67 private: 68 MachineFunctionProperties RequiredProperties; 69 MachineFunctionProperties SetProperties; 70 MachineFunctionProperties ClearedProperties; 71 72 /// createPrinterPass - Get a machine function printer pass. 73 Pass *createPrinterPass(raw_ostream &O, 74 const std::string &Banner) const override; 75 76 bool runOnFunction(Function &F) override; 77 }; 78 79 } // End llvm namespace 80 81 #endif 82
