1 //===- AliasAnalysisCounter.cpp - Alias Analysis Query Counter ------------===//
3 // This file implements a pass which can be used to count how many alias queries
4 // are being made and how the alias analysis implementation being used responds.
6 //===----------------------------------------------------------------------===//
8 #include "llvm/Analysis/AliasAnalysis.h"
13 unsigned No = 0, May = 0, Must = 0;
15 struct AliasAnalysisCounter : public Pass, public AliasAnalysis {
16 bool run(Module &M) { return false; }
17 virtual void getAnalysisUsage(AnalysisUsage &AU) const {
18 AU.addRequired<AliasAnalysis>();
22 Result count(Result R) {
24 default: assert(0 && "Unknown alias type!");
25 case NoAlias: No++; return NoAlias;
26 case MayAlias: May++; return MayAlias;
27 case MustAlias: Must++; return MustAlias;
31 // Forwarding functions: just delegate to a real AA implementation, counting
32 // the number of responses...
33 Result alias(const Value *V1, const Value *V2) {
34 return count(getAnalysis<AliasAnalysis>().alias(V1, V2));
36 Result canCallModify(const CallInst &CI, const Value *Ptr) {
37 return count(getAnalysis<AliasAnalysis>().canCallModify(CI, Ptr));
39 Result canInvokeModify(const InvokeInst &I, const Value *Ptr) {
40 return count(getAnalysis<AliasAnalysis>().canInvokeModify(I, Ptr));
44 RegisterOpt<AliasAnalysisCounter>
45 X("count-aa", "Count Alias Analysis Query Responses");
46 RegisterAnalysisGroup<AliasAnalysis, AliasAnalysisCounter> Y;
49 struct ResultPrinter {
51 unsigned Sum = No+May+Must;
52 if (Sum) { // Print a report if any counted queries occurred...
54 << "\n===== Alias Analysis Counter Report =====\n"
55 << " " << Sum << " Total Alias Queries Performed\n"
56 << " " << No << " no alias responses (" << No*100/Sum << "%)\n"
57 << " " << May << " may alias responses (" << May*100/Sum << "%)\n"
58 << " " << Must << " must alias responses (" <<Must*100/Sum<<"%)\n"
59 << " Alias Analysis Counter Summary: " << No*100/Sum << "%/"
60 << May*100/Sum << "%/" << Must*100/Sum<<"%\n\n";