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 <iostream>
  23
  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 LoaderPass : public ModulePass, public ProfileInfo {
  33     std::string Filename;
  34   public:
  35     LoaderPass(const std::string &filename = "")
  36       : Filename(filename) {
  37       if (filename.empty()) Filename = ProfileInfoFilename;
  38     }
  39
  40     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
  41       AU.setPreservesAll();
  42     }
  43
  44     virtual const char *getPassName() const {
  45       return "Profiling information loader";
  46     }
  47
  48     /// run - Load the profile information from the specified file.
  49     virtual bool runOnModule(Module &M);
  50   };
  51
  52   RegisterPass<LoaderPass>
  53   X("profile-loader", "Load profile information from llvmprof.out",
  54     PassInfo::Analysis|PassInfo::Optimization);
  55
  56   RegisterAnalysisGroup<ProfileInfo, LoaderPass> Y;
  57 }  // End of anonymous namespace
  58
  59 ModulePass *llvm::createProfileLoaderPass() { return new LoaderPass(); }
  60
  61 /// createProfileLoaderPass - This function returns a Pass that loads the
  62 /// profiling information for the module from the specified filename, making it
  63 /// available to the optimizers.
  64 Pass *llvm::createProfileLoaderPass(const std::string &Filename) {
  65   return new LoaderPass(Filename);
  66 }
  67
  68 bool LoaderPass::runOnModule(Module &M) {
  69   ProfileInfoLoader PIL("profile-loader", Filename, M);
  70   EdgeCounts.clear();
  71   bool PrintedWarning = false;
  72
  73   std::vector<std::pair<ProfileInfoLoader::Edge, unsigned> > ECs;
  74   PIL.getEdgeCounts(ECs);
  75   for (unsigned i = 0, e = ECs.size(); i != e; ++i) {
  76     BasicBlock *BB = ECs[i].first.first;
  77     unsigned SuccNum = ECs[i].first.second;
  78     TerminatorInst *TI = BB->getTerminator();
  79     if (SuccNum >= TI->getNumSuccessors()) {
  80       if (!PrintedWarning) {
  81         std::cerr << "WARNING: profile information is inconsistent with "
  82                   << "the current program!\n";
  83         PrintedWarning = true;
  84       }
  85     } else {
  86       EdgeCounts[std::make_pair(BB, TI->getSuccessor(SuccNum))]+= ECs[i].second;
  87     }
  88   }
  89
  90   return false;
  91 }