1 //===- MemDepPrinter.cpp - Printer for MemoryDependenceAnalysis -----------===//
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 //
11 //===----------------------------------------------------------------------===//
12
13 #include "llvm/Analysis/Passes.h"
14 #include "llvm/ADT/SetVector.h"
15 #include "llvm/Analysis/MemoryDependenceAnalysis.h"
16 #include "llvm/IR/CallSite.h"
17 #include "llvm/IR/InstIterator.h"
18 #include "llvm/IR/LLVMContext.h"
19 #include "llvm/Support/ErrorHandling.h"
20 #include "llvm/Support/raw_ostream.h"
21 using namespace llvm;
22
23 namespace {
24 struct MemDepPrinter : public FunctionPass {
25 const Function *F;
26
27 enum DepType {
28 Clobber = 0,
29 Def,
30 NonFuncLocal,
31 Unknown
32 };
33
34 static const char *const DepTypeStr[];
35
36 typedef PointerIntPair<const Instruction *, 2, DepType> InstTypePair;
37 typedef std::pair<InstTypePair, const BasicBlock *> Dep;
38 typedef SmallSetVector<Dep, 4> DepSet;
39 typedef DenseMap<const Instruction *, DepSet> DepSetMap;
40 DepSetMap Deps;
41
42 static char ID; // Pass identifcation, replacement for typeid
MemDepPrinter__anonc5571dc60111::MemDepPrinter43 MemDepPrinter() : FunctionPass(ID) {
44 initializeMemDepPrinterPass(*PassRegistry::getPassRegistry());
45 }
46
47 bool runOnFunction(Function &F) override;
48
49 void print(raw_ostream &OS, const Module * = nullptr) const override;
50
getAnalysisUsage__anonc5571dc60111::MemDepPrinter51 void getAnalysisUsage(AnalysisUsage &AU) const override {
52 AU.addRequiredTransitive<AAResultsWrapperPass>();
53 AU.addRequiredTransitive<MemoryDependenceAnalysis>();
54 AU.setPreservesAll();
55 }
56
releaseMemory__anonc5571dc60111::MemDepPrinter57 void releaseMemory() override {
58 Deps.clear();
59 F = nullptr;
60 }
61
62 private:
getInstTypePair__anonc5571dc60111::MemDepPrinter63 static InstTypePair getInstTypePair(MemDepResult dep) {
64 if (dep.isClobber())
65 return InstTypePair(dep.getInst(), Clobber);
66 if (dep.isDef())
67 return InstTypePair(dep.getInst(), Def);
68 if (dep.isNonFuncLocal())
69 return InstTypePair(dep.getInst(), NonFuncLocal);
70 assert(dep.isUnknown() && "unexpected dependence type");
71 return InstTypePair(dep.getInst(), Unknown);
72 }
getInstTypePair__anonc5571dc60111::MemDepPrinter73 static InstTypePair getInstTypePair(const Instruction* inst, DepType type) {
74 return InstTypePair(inst, type);
75 }
76 };
77 }
78
79 char MemDepPrinter::ID = 0;
80 INITIALIZE_PASS_BEGIN(MemDepPrinter, "print-memdeps",
81 "Print MemDeps of function", false, true)
INITIALIZE_PASS_DEPENDENCY(MemoryDependenceAnalysis)82 INITIALIZE_PASS_DEPENDENCY(MemoryDependenceAnalysis)
83 INITIALIZE_PASS_END(MemDepPrinter, "print-memdeps",
84 "Print MemDeps of function", false, true)
85
86 FunctionPass *llvm::createMemDepPrinter() {
87 return new MemDepPrinter();
88 }
89
90 const char *const MemDepPrinter::DepTypeStr[]
91 = {"Clobber", "Def", "NonFuncLocal", "Unknown"};
92
runOnFunction(Function & F)93 bool MemDepPrinter::runOnFunction(Function &F) {
94 this->F = &F;
95 MemoryDependenceAnalysis &MDA = getAnalysis<MemoryDependenceAnalysis>();
96
97 // All this code uses non-const interfaces because MemDep is not
98 // const-friendly, though nothing is actually modified.
99 for (auto &I : instructions(F)) {
100 Instruction *Inst = &I;
101
102 if (!Inst->mayReadFromMemory() && !Inst->mayWriteToMemory())
103 continue;
104
105 MemDepResult Res = MDA.getDependency(Inst);
106 if (!Res.isNonLocal()) {
107 Deps[Inst].insert(std::make_pair(getInstTypePair(Res),
108 static_cast<BasicBlock *>(nullptr)));
109 } else if (auto CS = CallSite(Inst)) {
110 const MemoryDependenceAnalysis::NonLocalDepInfo &NLDI =
111 MDA.getNonLocalCallDependency(CS);
112
113 DepSet &InstDeps = Deps[Inst];
114 for (MemoryDependenceAnalysis::NonLocalDepInfo::const_iterator
115 I = NLDI.begin(), E = NLDI.end(); I != E; ++I) {
116 const MemDepResult &Res = I->getResult();
117 InstDeps.insert(std::make_pair(getInstTypePair(Res), I->getBB()));
118 }
119 } else {
120 SmallVector<NonLocalDepResult, 4> NLDI;
121 assert( (isa<LoadInst>(Inst) || isa<StoreInst>(Inst) ||
122 isa<VAArgInst>(Inst)) && "Unknown memory instruction!");
123 MDA.getNonLocalPointerDependency(Inst, NLDI);
124
125 DepSet &InstDeps = Deps[Inst];
126 for (SmallVectorImpl<NonLocalDepResult>::const_iterator
127 I = NLDI.begin(), E = NLDI.end(); I != E; ++I) {
128 const MemDepResult &Res = I->getResult();
129 InstDeps.insert(std::make_pair(getInstTypePair(Res), I->getBB()));
130 }
131 }
132 }
133
134 return false;
135 }
136
print(raw_ostream & OS,const Module * M) const137 void MemDepPrinter::print(raw_ostream &OS, const Module *M) const {
138 for (const auto &I : instructions(*F)) {
139 const Instruction *Inst = &I;
140
141 DepSetMap::const_iterator DI = Deps.find(Inst);
142 if (DI == Deps.end())
143 continue;
144
145 const DepSet &InstDeps = DI->second;
146
147 for (const auto &I : InstDeps) {
148 const Instruction *DepInst = I.first.getPointer();
149 DepType type = I.first.getInt();
150 const BasicBlock *DepBB = I.second;
151
152 OS << " ";
153 OS << DepTypeStr[type];
154 if (DepBB) {
155 OS << " in block ";
156 DepBB->printAsOperand(OS, /*PrintType=*/false, M);
157 }
158 if (DepInst) {
159 OS << " from: ";
160 DepInst->print(OS);
161 }
162 OS << "\n";
163 }
164
165 Inst->print(OS);
166 OS << "\n\n";
167 }
168 }
169