1//===- StackSafetyAnalysis.h - Stack memory safety analysis -----*- 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// 9// Stack Safety Analysis detects allocas and arguments with safe access. 10// 11//===----------------------------------------------------------------------===// 12 13#ifndef LLVM_ANALYSIS_STACKSAFETYANALYSIS_H 14#define LLVM_ANALYSIS_STACKSAFETYANALYSIS_H 15 16#include "llvm/IR/ModuleSummaryIndex.h" 17#include "llvm/IR/PassManager.h" 18#include "llvm/Pass.h" 19 20namespace llvm { 21 22class AllocaInst; 23class ScalarEvolution; 24 25/// Interface to access stack safety analysis results for single function. 26class StackSafetyInfo { 27public: 28 struct InfoTy; 29 30private: 31 Function *F = nullptr; 32 std::function<ScalarEvolution &()> GetSE; 33 mutable std::unique_ptr<InfoTy> Info; 34 35public: 36 StackSafetyInfo(); 37 StackSafetyInfo(Function *F, std::function<ScalarEvolution &()> GetSE); 38 StackSafetyInfo(StackSafetyInfo &&); 39 StackSafetyInfo &operator=(StackSafetyInfo &&); 40 ~StackSafetyInfo(); 41 42 const InfoTy &getInfo() const; 43 44 // TODO: Add useful for client methods. 45 void print(raw_ostream &O) const; 46 47 /// Parameters use for a FunctionSummary. 48 /// Function collects access information of all pointer parameters. 49 /// Information includes a range of direct access of parameters by the 50 /// functions and all call sites accepting the parameter. 51 /// StackSafety assumes that missing parameter information means possibility 52 /// of access to the parameter with any offset, so we can correctly link 53 /// code without StackSafety information, e.g. non-ThinLTO. 54 std::vector<FunctionSummary::ParamAccess> getParamAccesses() const; 55}; 56 57class StackSafetyGlobalInfo { 58public: 59 struct InfoTy; 60 61private: 62 Module *M = nullptr; 63 std::function<const StackSafetyInfo &(Function &F)> GetSSI; 64 const ModuleSummaryIndex *Index = nullptr; 65 mutable std::unique_ptr<InfoTy> Info; 66 const InfoTy &getInfo() const; 67 68public: 69 StackSafetyGlobalInfo(); 70 StackSafetyGlobalInfo( 71 Module *M, std::function<const StackSafetyInfo &(Function &F)> GetSSI, 72 const ModuleSummaryIndex *Index); 73 StackSafetyGlobalInfo(StackSafetyGlobalInfo &&); 74 StackSafetyGlobalInfo &operator=(StackSafetyGlobalInfo &&); 75 ~StackSafetyGlobalInfo(); 76 77 bool isSafe(const AllocaInst &AI) const; 78 void print(raw_ostream &O) const; 79 void dump() const; 80}; 81 82/// StackSafetyInfo wrapper for the new pass manager. 83class StackSafetyAnalysis : public AnalysisInfoMixin<StackSafetyAnalysis> { 84 friend AnalysisInfoMixin<StackSafetyAnalysis>; 85 static AnalysisKey Key; 86 87public: 88 using Result = StackSafetyInfo; 89 StackSafetyInfo run(Function &F, FunctionAnalysisManager &AM); 90}; 91 92/// Printer pass for the \c StackSafetyAnalysis results. 93class StackSafetyPrinterPass : public PassInfoMixin<StackSafetyPrinterPass> { 94 raw_ostream &OS; 95 96public: 97 explicit StackSafetyPrinterPass(raw_ostream &OS) : OS(OS) {} 98 PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM); 99}; 100 101/// StackSafetyInfo wrapper for the legacy pass manager 102class StackSafetyInfoWrapperPass : public FunctionPass { 103 StackSafetyInfo SSI; 104 105public: 106 static char ID; 107 StackSafetyInfoWrapperPass(); 108 109 const StackSafetyInfo &getResult() const { return SSI; } 110 111 void print(raw_ostream &O, const Module *M) const override; 112 void getAnalysisUsage(AnalysisUsage &AU) const override; 113 114 bool runOnFunction(Function &F) override; 115}; 116 117/// This pass performs the global (interprocedural) stack safety analysis (new 118/// pass manager). 119class StackSafetyGlobalAnalysis 120 : public AnalysisInfoMixin<StackSafetyGlobalAnalysis> { 121 friend AnalysisInfoMixin<StackSafetyGlobalAnalysis>; 122 static AnalysisKey Key; 123 124public: 125 using Result = StackSafetyGlobalInfo; 126 Result run(Module &M, ModuleAnalysisManager &AM); 127}; 128 129/// Printer pass for the \c StackSafetyGlobalAnalysis results. 130class StackSafetyGlobalPrinterPass 131 : public PassInfoMixin<StackSafetyGlobalPrinterPass> { 132 raw_ostream &OS; 133 134public: 135 explicit StackSafetyGlobalPrinterPass(raw_ostream &OS) : OS(OS) {} 136 PreservedAnalyses run(Module &M, ModuleAnalysisManager &AM); 137}; 138 139/// This pass performs the global (interprocedural) stack safety analysis 140/// (legacy pass manager). 141class StackSafetyGlobalInfoWrapperPass : public ModulePass { 142 StackSafetyGlobalInfo SSGI; 143 144public: 145 static char ID; 146 147 StackSafetyGlobalInfoWrapperPass(); 148 ~StackSafetyGlobalInfoWrapperPass(); 149 150 const StackSafetyGlobalInfo &getResult() const { return SSGI; } 151 152 void print(raw_ostream &O, const Module *M) const override; 153 void getAnalysisUsage(AnalysisUsage &AU) const override; 154 155 bool runOnModule(Module &M) override; 156}; 157 158bool needsParamAccessSummary(const Module &M); 159 160void generateParamAccessSummary(ModuleSummaryIndex &Index); 161 162} // end namespace llvm 163 164#endif // LLVM_ANALYSIS_STACKSAFETYANALYSIS_H 165