1 //===- AliasAnalysisEvaluator.cpp - Alias Analysis Accuracy Evaluator -----===//
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 //===----------------------------------------------------------------------===//
10 #include "llvm/Analysis/AliasAnalysisEvaluator.h"
11 #include "llvm/ADT/SetVector.h"
12 #include "llvm/Analysis/AliasAnalysis.h"
13 #include "llvm/IR/Constants.h"
14 #include "llvm/IR/DataLayout.h"
15 #include "llvm/IR/DerivedTypes.h"
16 #include "llvm/IR/Function.h"
17 #include "llvm/IR/InstIterator.h"
18 #include "llvm/IR/Instructions.h"
19 #include "llvm/IR/Module.h"
20 #include "llvm/Pass.h"
21 #include "llvm/Support/CommandLine.h"
22 #include "llvm/Support/Debug.h"
23 #include "llvm/Support/raw_ostream.h"
26 static cl::opt<bool> PrintAll("print-all-alias-modref-info", cl::ReallyHidden);
28 static cl::opt<bool> PrintNoAlias("print-no-aliases", cl::ReallyHidden);
29 static cl::opt<bool> PrintMayAlias("print-may-aliases", cl::ReallyHidden);
30 static cl::opt<bool> PrintPartialAlias("print-partial-aliases", cl::ReallyHidden);
31 static cl::opt<bool> PrintMustAlias("print-must-aliases", cl::ReallyHidden);
33 static cl::opt<bool> PrintNoModRef("print-no-modref", cl::ReallyHidden);
34 static cl::opt<bool> PrintRef("print-ref", cl::ReallyHidden);
35 static cl::opt<bool> PrintMod("print-mod", cl::ReallyHidden);
36 static cl::opt<bool> PrintModRef("print-modref", cl::ReallyHidden);
37 static cl::opt<bool> PrintMust("print-must", cl::ReallyHidden);
38 static cl::opt<bool> PrintMustRef("print-mustref", cl::ReallyHidden);
39 static cl::opt<bool> PrintMustMod("print-mustmod", cl::ReallyHidden);
40 static cl::opt<bool> PrintMustModRef("print-mustmodref", cl::ReallyHidden);
42 static cl::opt<bool> EvalAAMD("evaluate-aa-metadata", cl::ReallyHidden);
44 static void PrintResults(const char *Msg, bool P, const Value *V1,
45 const Value *V2, const Module *M) {
49 raw_string_ostream os1(o1), os2(o2);
50 V1->printAsOperand(os1, true, M);
51 V2->printAsOperand(os2, true, M);
56 errs() << " " << Msg << ":\t"
63 PrintModRefResults(const char *Msg, bool P, Instruction *I, Value *Ptr,
66 errs() << " " << Msg << ": Ptr: ";
67 Ptr->printAsOperand(errs(), true, M);
68 errs() << "\t<->" << *I << '\n';
73 PrintModRefResults(const char *Msg, bool P, CallSite CSA, CallSite CSB,
76 errs() << " " << Msg << ": " << *CSA.getInstruction()
77 << " <-> " << *CSB.getInstruction() << '\n';
82 PrintLoadStoreResults(const char *Msg, bool P, const Value *V1,
83 const Value *V2, const Module *M) {
85 errs() << " " << Msg << ": " << *V1
86 << " <-> " << *V2 << '\n';
90 static inline bool isInterestingPointer(Value *V) {
91 return V->getType()->isPointerTy()
92 && !isa<ConstantPointerNull>(V);
95 PreservedAnalyses AAEvaluator::run(Function &F, FunctionAnalysisManager &AM) {
96 runInternal(F, AM.getResult<AAManager>(F));
97 return PreservedAnalyses::all();
100 void AAEvaluator::runInternal(Function &F, AAResults &AA) {
101 const DataLayout &DL = F.getParent()->getDataLayout();
105 SetVector<Value *> Pointers;
106 SmallSetVector<CallSite, 16> CallSites;
107 SetVector<Value *> Loads;
108 SetVector<Value *> Stores;
110 for (auto &I : F.args())
111 if (I.getType()->isPointerTy()) // Add all pointer arguments.
114 for (inst_iterator I = inst_begin(F), E = inst_end(F); I != E; ++I) {
115 if (I->getType()->isPointerTy()) // Add all pointer instructions.
116 Pointers.insert(&*I);
117 if (EvalAAMD && isa<LoadInst>(&*I))
119 if (EvalAAMD && isa<StoreInst>(&*I))
121 Instruction &Inst = *I;
122 if (auto CS = CallSite(&Inst)) {
123 Value *Callee = CS.getCalledValue();
124 // Skip actual functions for direct function calls.
125 if (!isa<Function>(Callee) && isInterestingPointer(Callee))
126 Pointers.insert(Callee);
128 for (Use &DataOp : CS.data_ops())
129 if (isInterestingPointer(DataOp))
130 Pointers.insert(DataOp);
131 CallSites.insert(CS);
133 // Consider all operands.
134 for (Instruction::op_iterator OI = Inst.op_begin(), OE = Inst.op_end();
136 if (isInterestingPointer(*OI))
137 Pointers.insert(*OI);
141 if (PrintAll || PrintNoAlias || PrintMayAlias || PrintPartialAlias ||
142 PrintMustAlias || PrintNoModRef || PrintMod || PrintRef || PrintModRef)
143 errs() << "Function: " << F.getName() << ": " << Pointers.size()
144 << " pointers, " << CallSites.size() << " call sites\n";
146 // iterate over the worklist, and run the full (n^2)/2 disambiguations
147 for (SetVector<Value *>::iterator I1 = Pointers.begin(), E = Pointers.end();
149 uint64_t I1Size = MemoryLocation::UnknownSize;
150 Type *I1ElTy = cast<PointerType>((*I1)->getType())->getElementType();
151 if (I1ElTy->isSized()) I1Size = DL.getTypeStoreSize(I1ElTy);
153 for (SetVector<Value *>::iterator I2 = Pointers.begin(); I2 != I1; ++I2) {
154 uint64_t I2Size = MemoryLocation::UnknownSize;
155 Type *I2ElTy =cast<PointerType>((*I2)->getType())->getElementType();
156 if (I2ElTy->isSized()) I2Size = DL.getTypeStoreSize(I2ElTy);
158 switch (AA.alias(*I1, I1Size, *I2, I2Size)) {
160 PrintResults("NoAlias", PrintNoAlias, *I1, *I2, F.getParent());
164 PrintResults("MayAlias", PrintMayAlias, *I1, *I2, F.getParent());
168 PrintResults("PartialAlias", PrintPartialAlias, *I1, *I2,
173 PrintResults("MustAlias", PrintMustAlias, *I1, *I2, F.getParent());
181 // iterate over all pairs of load, store
182 for (Value *Load : Loads) {
183 for (Value *Store : Stores) {
184 switch (AA.alias(MemoryLocation::get(cast<LoadInst>(Load)),
185 MemoryLocation::get(cast<StoreInst>(Store)))) {
187 PrintLoadStoreResults("NoAlias", PrintNoAlias, Load, Store,
192 PrintLoadStoreResults("MayAlias", PrintMayAlias, Load, Store,
197 PrintLoadStoreResults("PartialAlias", PrintPartialAlias, Load, Store,
202 PrintLoadStoreResults("MustAlias", PrintMustAlias, Load, Store,
210 // iterate over all pairs of store, store
211 for (SetVector<Value *>::iterator I1 = Stores.begin(), E = Stores.end();
213 for (SetVector<Value *>::iterator I2 = Stores.begin(); I2 != I1; ++I2) {
214 switch (AA.alias(MemoryLocation::get(cast<StoreInst>(*I1)),
215 MemoryLocation::get(cast<StoreInst>(*I2)))) {
217 PrintLoadStoreResults("NoAlias", PrintNoAlias, *I1, *I2,
222 PrintLoadStoreResults("MayAlias", PrintMayAlias, *I1, *I2,
227 PrintLoadStoreResults("PartialAlias", PrintPartialAlias, *I1, *I2,
232 PrintLoadStoreResults("MustAlias", PrintMustAlias, *I1, *I2,
241 // Mod/ref alias analysis: compare all pairs of calls and values
242 for (CallSite C : CallSites) {
243 Instruction *I = C.getInstruction();
245 for (auto Pointer : Pointers) {
246 uint64_t Size = MemoryLocation::UnknownSize;
247 Type *ElTy = cast<PointerType>(Pointer->getType())->getElementType();
248 if (ElTy->isSized()) Size = DL.getTypeStoreSize(ElTy);
250 switch (AA.getModRefInfo(C, Pointer, Size)) {
251 case ModRefInfo::NoModRef:
252 PrintModRefResults("NoModRef", PrintNoModRef, I, Pointer,
256 case ModRefInfo::Mod:
257 PrintModRefResults("Just Mod", PrintMod, I, Pointer, F.getParent());
260 case ModRefInfo::Ref:
261 PrintModRefResults("Just Ref", PrintRef, I, Pointer, F.getParent());
264 case ModRefInfo::ModRef:
265 PrintModRefResults("Both ModRef", PrintModRef, I, Pointer,
269 case ModRefInfo::Must:
270 PrintModRefResults("Must", PrintMust, I, Pointer, F.getParent());
273 case ModRefInfo::MustMod:
274 PrintModRefResults("Just Mod (MustAlias)", PrintMustMod, I, Pointer,
278 case ModRefInfo::MustRef:
279 PrintModRefResults("Just Ref (MustAlias)", PrintMustRef, I, Pointer,
283 case ModRefInfo::MustModRef:
284 PrintModRefResults("Both ModRef (MustAlias)", PrintMustModRef, I,
285 Pointer, F.getParent());
292 // Mod/ref alias analysis: compare all pairs of calls
293 for (auto C = CallSites.begin(), Ce = CallSites.end(); C != Ce; ++C) {
294 for (auto D = CallSites.begin(); D != Ce; ++D) {
297 switch (AA.getModRefInfo(*C, *D)) {
298 case ModRefInfo::NoModRef:
299 PrintModRefResults("NoModRef", PrintNoModRef, *C, *D, F.getParent());
302 case ModRefInfo::Mod:
303 PrintModRefResults("Just Mod", PrintMod, *C, *D, F.getParent());
306 case ModRefInfo::Ref:
307 PrintModRefResults("Just Ref", PrintRef, *C, *D, F.getParent());
310 case ModRefInfo::ModRef:
311 PrintModRefResults("Both ModRef", PrintModRef, *C, *D, F.getParent());
314 case ModRefInfo::Must:
315 PrintModRefResults("Must", PrintMust, *C, *D, F.getParent());
318 case ModRefInfo::MustMod:
319 PrintModRefResults("Just Mod (MustAlias)", PrintMustMod, *C, *D,
323 case ModRefInfo::MustRef:
324 PrintModRefResults("Just Ref (MustAlias)", PrintMustRef, *C, *D,
328 case ModRefInfo::MustModRef:
329 PrintModRefResults("Both ModRef (MustAlias)", PrintMustModRef, *C, *D,
338 static void PrintPercent(int64_t Num, int64_t Sum) {
339 errs() << "(" << Num * 100LL / Sum << "." << ((Num * 1000LL / Sum) % 10)
343 AAEvaluator::~AAEvaluator() {
344 if (FunctionCount == 0)
348 NoAliasCount + MayAliasCount + PartialAliasCount + MustAliasCount;
349 errs() << "===== Alias Analysis Evaluator Report =====\n";
351 errs() << " Alias Analysis Evaluator Summary: No pointers!\n";
353 errs() << " " << AliasSum << " Total Alias Queries Performed\n";
354 errs() << " " << NoAliasCount << " no alias responses ";
355 PrintPercent(NoAliasCount, AliasSum);
356 errs() << " " << MayAliasCount << " may alias responses ";
357 PrintPercent(MayAliasCount, AliasSum);
358 errs() << " " << PartialAliasCount << " partial alias responses ";
359 PrintPercent(PartialAliasCount, AliasSum);
360 errs() << " " << MustAliasCount << " must alias responses ";
361 PrintPercent(MustAliasCount, AliasSum);
362 errs() << " Alias Analysis Evaluator Pointer Alias Summary: "
363 << NoAliasCount * 100 / AliasSum << "%/"
364 << MayAliasCount * 100 / AliasSum << "%/"
365 << PartialAliasCount * 100 / AliasSum << "%/"
366 << MustAliasCount * 100 / AliasSum << "%\n";
369 // Display the summary for mod/ref analysis
370 int64_t ModRefSum = NoModRefCount + RefCount + ModCount + ModRefCount +
371 MustCount + MustRefCount + MustModCount + MustModRefCount;
372 if (ModRefSum == 0) {
373 errs() << " Alias Analysis Mod/Ref Evaluator Summary: no "
376 errs() << " " << ModRefSum << " Total ModRef Queries Performed\n";
377 errs() << " " << NoModRefCount << " no mod/ref responses ";
378 PrintPercent(NoModRefCount, ModRefSum);
379 errs() << " " << ModCount << " mod responses ";
380 PrintPercent(ModCount, ModRefSum);
381 errs() << " " << RefCount << " ref responses ";
382 PrintPercent(RefCount, ModRefSum);
383 errs() << " " << ModRefCount << " mod & ref responses ";
384 PrintPercent(ModRefCount, ModRefSum);
385 errs() << " " << MustCount << " must responses ";
386 PrintPercent(MustCount, ModRefSum);
387 errs() << " " << MustModCount << " must mod responses ";
388 PrintPercent(MustModCount, ModRefSum);
389 errs() << " " << MustRefCount << " must ref responses ";
390 PrintPercent(MustRefCount, ModRefSum);
391 errs() << " " << MustModRefCount << " must mod & ref responses ";
392 PrintPercent(MustModRefCount, ModRefSum);
393 errs() << " Alias Analysis Evaluator Mod/Ref Summary: "
394 << NoModRefCount * 100 / ModRefSum << "%/"
395 << ModCount * 100 / ModRefSum << "%/" << RefCount * 100 / ModRefSum
396 << "%/" << ModRefCount * 100 / ModRefSum << "%/"
397 << MustCount * 100 / ModRefSum << "%/"
398 << MustRefCount * 100 / ModRefSum << "%/"
399 << MustModCount * 100 / ModRefSum << "%/"
400 << MustModRefCount * 100 / ModRefSum << "%\n";
405 class AAEvalLegacyPass : public FunctionPass {
406 std::unique_ptr<AAEvaluator> P;
409 static char ID; // Pass identification, replacement for typeid
410 AAEvalLegacyPass() : FunctionPass(ID) {
411 initializeAAEvalLegacyPassPass(*PassRegistry::getPassRegistry());
414 void getAnalysisUsage(AnalysisUsage &AU) const override {
415 AU.addRequired<AAResultsWrapperPass>();
416 AU.setPreservesAll();
419 bool doInitialization(Module &M) override {
420 P.reset(new AAEvaluator());
424 bool runOnFunction(Function &F) override {
425 P->runInternal(F, getAnalysis<AAResultsWrapperPass>().getAAResults());
428 bool doFinalization(Module &M) override {
435 char AAEvalLegacyPass::ID = 0;
436 INITIALIZE_PASS_BEGIN(AAEvalLegacyPass, "aa-eval",
437 "Exhaustive Alias Analysis Precision Evaluator", false,
439 INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)
440 INITIALIZE_PASS_END(AAEvalLegacyPass, "aa-eval",
441 "Exhaustive Alias Analysis Precision Evaluator", false,
444 FunctionPass *llvm::createAAEvalPass() { return new AAEvalLegacyPass(); }