ProfileInfoLoaderPass.cpp revision 4ee451de366474b9c228b4e5fa573795a715216d 
1//===- ProfileInfoLoaderPass.cpp - LLVM Pass to load profile info ---------===//
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// This file implements a concrete implementation of profiling information that
11// loads the information from a profile dump file.
12//
13//===----------------------------------------------------------------------===//
14
15#include "llvm/BasicBlock.h"
16#include "llvm/InstrTypes.h"
17#include "llvm/Pass.h"
18#include "llvm/Analysis/Passes.h"
19#include "llvm/Analysis/ProfileInfo.h"
20#include "llvm/Analysis/ProfileInfoLoader.h"
21#include "llvm/Support/CommandLine.h"
22#include "llvm/Support/Compiler.h"
23#include "llvm/Support/Streams.h"
24using namespace llvm;
25
26namespace {
27  cl::opt<std::string>
28  ProfileInfoFilename("profile-info-file", cl::init("llvmprof.out"),
29                      cl::value_desc("filename"),
30                      cl::desc("Profile file loaded by -profile-loader"));
31
32  class VISIBILITY_HIDDEN LoaderPass : public ModulePass, public ProfileInfo {
33    std::string Filename;
34  public:
35    static char ID; // Class identification, replacement for typeinfo
36    explicit LoaderPass(const std::string &filename = "")
37      : ModulePass((intptr_t)&ID), Filename(filename) {
38      if (filename.empty()) Filename = ProfileInfoFilename;
39    }
40
41    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
42      AU.setPreservesAll();
43    }
44
45    virtual const char *getPassName() const {
46      return "Profiling information loader";
47    }
48
49    /// run - Load the profile information from the specified file.
50    virtual bool runOnModule(Module &M);
51  };
52
53  char LoaderPass::ID = 0;
54  RegisterPass<LoaderPass>
55  X("profile-loader", "Load profile information from llvmprof.out");
56
57  RegisterAnalysisGroup<ProfileInfo> Y(X);
58}  // End of anonymous namespace
59
60ModulePass *llvm::createProfileLoaderPass() { return new LoaderPass(); }
61
62/// createProfileLoaderPass - This function returns a Pass that loads the
63/// profiling information for the module from the specified filename, making it
64/// available to the optimizers.
65Pass *llvm::createProfileLoaderPass(const std::string &Filename) {
66  return new LoaderPass(Filename);
67}
68
69bool LoaderPass::runOnModule(Module &M) {
70  ProfileInfoLoader PIL("profile-loader", Filename, M);
71  EdgeCounts.clear();
72  bool PrintedWarning = false;
73
74  std::vector<std::pair<ProfileInfoLoader::Edge, unsigned> > ECs;
75  PIL.getEdgeCounts(ECs);
76  for (unsigned i = 0, e = ECs.size(); i != e; ++i) {
77    BasicBlock *BB = ECs[i].first.first;
78    unsigned SuccNum = ECs[i].first.second;
79    TerminatorInst *TI = BB->getTerminator();
80    if (SuccNum >= TI->getNumSuccessors()) {
81      if (!PrintedWarning) {
82        cerr << "WARNING: profile information is inconsistent with "
83             << "the current program!\n";
84        PrintedWarning = true;
85      }
86    } else {
87      EdgeCounts[std::make_pair(BB, TI->getSuccessor(SuccNum))]+= ECs[i].second;
88    }
89  }
90
91  return false;
92}
93