1 //===- MemDepPrinter.cpp - Printer for MemoryDependenceAnalysis -----------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 //===----------------------------------------------------------------------===//
13 #include "llvm/Analysis/MemoryDependenceAnalysis.h"
14 #include "llvm/LLVMContext.h"
15 #include "llvm/Analysis/Passes.h"
16 #include "llvm/Assembly/Writer.h"
17 #include "llvm/Support/CallSite.h"
18 #include "llvm/Support/InstIterator.h"
19 #include "llvm/Support/ErrorHandling.h"
20 #include "llvm/Support/raw_ostream.h"
21 #include "llvm/ADT/SetVector.h"
25 struct MemDepPrinter : public FunctionPass {
28 typedef PointerIntPair<const Instruction *, 1> InstAndClobberFlag;
29 typedef std::pair<InstAndClobberFlag, const BasicBlock *> Dep;
30 typedef SmallSetVector<Dep, 4> DepSet;
31 typedef DenseMap<const Instruction *, DepSet> DepSetMap;
34 static char ID; // Pass identifcation, replacement for typeid
35 MemDepPrinter() : FunctionPass(ID) {
36 initializeMemDepPrinterPass(*PassRegistry::getPassRegistry());
39 virtual bool runOnFunction(Function &F);
41 void print(raw_ostream &OS, const Module * = 0) const;
43 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
44 AU.addRequiredTransitive<AliasAnalysis>();
45 AU.addRequiredTransitive<MemoryDependenceAnalysis>();
49 virtual void releaseMemory() {
56 char MemDepPrinter::ID = 0;
57 INITIALIZE_PASS_BEGIN(MemDepPrinter, "print-memdeps",
58 "Print MemDeps of function", false, true)
59 INITIALIZE_PASS_DEPENDENCY(MemoryDependenceAnalysis)
60 INITIALIZE_PASS_END(MemDepPrinter, "print-memdeps",
61 "Print MemDeps of function", false, true)
63 FunctionPass *llvm::createMemDepPrinter() {
64 return new MemDepPrinter();
67 bool MemDepPrinter::runOnFunction(Function &F) {
69 AliasAnalysis &AA = getAnalysis<AliasAnalysis>();
70 MemoryDependenceAnalysis &MDA = getAnalysis<MemoryDependenceAnalysis>();
72 // All this code uses non-const interfaces because MemDep is not
73 // const-friendly, though nothing is actually modified.
74 for (inst_iterator I = inst_begin(F), E = inst_end(F); I != E; ++I) {
75 Instruction *Inst = &*I;
77 if (!Inst->mayReadFromMemory() && !Inst->mayWriteToMemory())
80 MemDepResult Res = MDA.getDependency(Inst);
81 if (!Res.isNonLocal()) {
82 assert((Res.isUnknown() || Res.isClobber() || Res.isDef()) &&
83 "Local dep should be unknown, def or clobber!");
84 Deps[Inst].insert(std::make_pair(InstAndClobberFlag(Res.getInst(),
86 static_cast<BasicBlock *>(0)));
87 } else if (CallSite CS = cast<Value>(Inst)) {
88 const MemoryDependenceAnalysis::NonLocalDepInfo &NLDI =
89 MDA.getNonLocalCallDependency(CS);
91 DepSet &InstDeps = Deps[Inst];
92 for (MemoryDependenceAnalysis::NonLocalDepInfo::const_iterator
93 I = NLDI.begin(), E = NLDI.end(); I != E; ++I) {
94 const MemDepResult &Res = I->getResult();
95 assert((Res.isUnknown() || Res.isClobber() || Res.isDef()) &&
96 "Resolved non-local call dep should be unknown, def or "
98 InstDeps.insert(std::make_pair(InstAndClobberFlag(Res.getInst(),
103 SmallVector<NonLocalDepResult, 4> NLDI;
104 if (LoadInst *LI = dyn_cast<LoadInst>(Inst)) {
105 if (!LI->isUnordered()) {
106 // FIXME: Handle atomic/volatile loads.
107 Deps[Inst].insert(std::make_pair(InstAndClobberFlag(0, false),
108 static_cast<BasicBlock *>(0)));
111 AliasAnalysis::Location Loc = AA.getLocation(LI);
112 MDA.getNonLocalPointerDependency(Loc, true, LI->getParent(), NLDI);
113 } else if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
114 if (!LI->isUnordered()) {
115 // FIXME: Handle atomic/volatile stores.
116 Deps[Inst].insert(std::make_pair(InstAndClobberFlag(0, false),
117 static_cast<BasicBlock *>(0)));
120 AliasAnalysis::Location Loc = AA.getLocation(SI);
121 MDA.getNonLocalPointerDependency(Loc, false, SI->getParent(), NLDI);
122 } else if (VAArgInst *VI = dyn_cast<VAArgInst>(Inst)) {
123 AliasAnalysis::Location Loc = AA.getLocation(VI);
124 MDA.getNonLocalPointerDependency(Loc, false, VI->getParent(), NLDI);
126 llvm_unreachable("Unknown memory instruction!");
129 DepSet &InstDeps = Deps[Inst];
130 for (SmallVectorImpl<NonLocalDepResult>::const_iterator
131 I = NLDI.begin(), E = NLDI.end(); I != E; ++I) {
132 const MemDepResult &Res = I->getResult();
133 assert(Res.isClobber() != Res.isDef() &&
134 "Resolved non-local pointer dep should be def or clobber!");
135 InstDeps.insert(std::make_pair(InstAndClobberFlag(Res.getInst(),
145 void MemDepPrinter::print(raw_ostream &OS, const Module *M) const {
146 for (const_inst_iterator I = inst_begin(*F), E = inst_end(*F); I != E; ++I) {
147 const Instruction *Inst = &*I;
149 DepSetMap::const_iterator DI = Deps.find(Inst);
150 if (DI == Deps.end())
153 const DepSet &InstDeps = DI->second;
155 for (DepSet::const_iterator I = InstDeps.begin(), E = InstDeps.end();
157 const Instruction *DepInst = I->first.getPointer();
158 bool isClobber = I->first.getInt();
159 const BasicBlock *DepBB = I->second;
170 WriteAsOperand(OS, DepBB, /*PrintType=*/false, M);
175 OS << "<unspecified>";