1 //==- RegisterUsageInfo.h - Register Usage Informartion Storage --*- C++ -*-==// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 /// \file 9 /// This pass is required to take advantage of the interprocedural register 10 /// allocation infrastructure. 11 /// 12 /// This pass is simple immutable pass which keeps RegMasks (calculated based on 13 /// actual register allocation) for functions in a module and provides simple 14 /// API to query this information. 15 /// 16 //===----------------------------------------------------------------------===// 17 18 #ifndef LLVM_CODEGEN_PHYSICALREGISTERUSAGEINFO_H 19 #define LLVM_CODEGEN_PHYSICALREGISTERUSAGEINFO_H 20 21 #include "llvm/ADT/ArrayRef.h" 22 #include "llvm/ADT/DenseMap.h" 23 #include "llvm/IR/Instructions.h" 24 #include "llvm/InitializePasses.h" 25 #include "llvm/Pass.h" 26 #include <cstdint> 27 #include <vector> 28 29 namespace llvm { 30 31 class Function; 32 class LLVMTargetMachine; 33 34 class PhysicalRegisterUsageInfo : public ImmutablePass { 35 public: 36 static char ID; 37 38 PhysicalRegisterUsageInfo() : ImmutablePass(ID) { 39 PassRegistry &Registry = *PassRegistry::getPassRegistry(); 40 initializePhysicalRegisterUsageInfoPass(Registry); 41 } 42 43 /// Set TargetMachine which is used to print analysis. 44 void setTargetMachine(const LLVMTargetMachine &TM); 45 46 bool doInitialization(Module &M) override; 47 48 bool doFinalization(Module &M) override; 49 50 /// To store RegMask for given Function *. 51 void storeUpdateRegUsageInfo(const Function &FP, 52 ArrayRef<uint32_t> RegMask); 53 54 /// To query stored RegMask for given Function *, it will returns ane empty 55 /// array if function is not known. 56 ArrayRef<uint32_t> getRegUsageInfo(const Function &FP); 57 58 void print(raw_ostream &OS, const Module *M = nullptr) const override; 59 60 private: 61 /// A Dense map from Function * to RegMask. 62 /// In RegMask 0 means register used (clobbered) by function. 63 /// and 1 means content of register will be preserved around function call. 64 DenseMap<const Function *, std::vector<uint32_t>> RegMasks; 65 66 const LLVMTargetMachine *TM; 67 }; 68 69 } // end namespace llvm 70 71 #endif // LLVM_CODEGEN_PHYSICALREGISTERUSAGEINFO_H 72