1 //===- MemDerefPrinter.cpp - Printer for isDereferenceablePointer ---------===// 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 #include "llvm/Analysis/Passes.h" 11 #include "llvm/ADT/SetVector.h" 12 #include "llvm/Analysis/MemoryDependenceAnalysis.h" 13 #include "llvm/Analysis/Loads.h" 14 #include "llvm/IR/CallSite.h" 15 #include "llvm/IR/DataLayout.h" 16 #include "llvm/IR/InstIterator.h" 17 #include "llvm/IR/LLVMContext.h" 18 #include "llvm/IR/Module.h" 19 #include "llvm/Support/ErrorHandling.h" 20 #include "llvm/Support/raw_ostream.h" 21 using namespace llvm; 22 23 namespace { 24 struct MemDerefPrinter : public FunctionPass { 25 SmallVector<Value *, 4> Deref; 26 SmallPtrSet<Value *, 4> DerefAndAligned; 27 28 static char ID; // Pass identification, replacement for typeid 29 MemDerefPrinter() : FunctionPass(ID) { 30 initializeMemDerefPrinterPass(*PassRegistry::getPassRegistry()); 31 } 32 void getAnalysisUsage(AnalysisUsage &AU) const override { 33 AU.setPreservesAll(); 34 } 35 bool runOnFunction(Function &F) override; 36 void print(raw_ostream &OS, const Module * = nullptr) const override; 37 void releaseMemory() override { 38 Deref.clear(); 39 DerefAndAligned.clear(); 40 } 41 }; 42 } 43 44 char MemDerefPrinter::ID = 0; 45 INITIALIZE_PASS_BEGIN(MemDerefPrinter, "print-memderefs", 46 "Memory Dereferenciblity of pointers in function", false, true) 47 INITIALIZE_PASS_END(MemDerefPrinter, "print-memderefs", 48 "Memory Dereferenciblity of pointers in function", false, true) 49 50 FunctionPass *llvm::createMemDerefPrinter() { 51 return new MemDerefPrinter(); 52 } 53 54 bool MemDerefPrinter::runOnFunction(Function &F) { 55 const DataLayout &DL = F.getParent()->getDataLayout(); 56 for (auto &I: instructions(F)) { 57 if (LoadInst *LI = dyn_cast<LoadInst>(&I)) { 58 Value *PO = LI->getPointerOperand(); 59 if (isDereferenceablePointer(PO, DL)) 60 Deref.push_back(PO); 61 if (isDereferenceableAndAlignedPointer(PO, LI->getAlignment(), DL)) 62 DerefAndAligned.insert(PO); 63 } 64 } 65 return false; 66 } 67 68 void MemDerefPrinter::print(raw_ostream &OS, const Module *M) const { 69 OS << "The following are dereferenceable:\n"; 70 for (Value *V: Deref) { 71 V->print(OS); 72 if (DerefAndAligned.count(V)) 73 OS << "\t(aligned)"; 74 else 75 OS << "\t(unaligned)"; 76 OS << "\n\n"; 77 } 78 } 79
