lib/Analysis/ProfileInfoLoaderPass.cpp

   1 //===- ProfileInfoLoaderPass.cpp - LLVM Pass to load profile info ---------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file was developed by the LLVM research group and is distributed under
   6 // the University of Illinois Open Source 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"
  24 using namespace llvm;
  25
  26 namespace {
  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     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
  60 ModulePass *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.
  65 Pass *llvm::createProfileLoaderPass(const std::string &Filename) {
  66   return new LoaderPass(Filename);
  67 }
  68
  69 bool 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 }