1 //===- PathProfileVerifier.cpp --------------------------------*- C++ -*---===// 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 verifier derives an edge profile file from current path profile 11 // information 12 // 13 //===----------------------------------------------------------------------===// 14 #define DEBUG_TYPE "path-profile-verifier" 15 16 #include "llvm/Module.h" 17 #include "llvm/Pass.h" 18 #include "llvm/Analysis/Passes.h" 19 #include "llvm/Analysis/ProfileInfoTypes.h" 20 #include "llvm/Analysis/PathProfileInfo.h" 21 #include "llvm/Support/Debug.h" 22 #include "llvm/Support/CommandLine.h" 23 #include "llvm/Support/raw_ostream.h" 24 25 #include <stdio.h> 26 27 using namespace llvm; 28 29 namespace { 30 class PathProfileVerifier : public ModulePass { 31 private: 32 bool runOnModule(Module &M); 33 34 public: 35 static char ID; // Pass identification, replacement for typeid 36 PathProfileVerifier() : ModulePass(ID) { 37 initializePathProfileVerifierPass(*PassRegistry::getPassRegistry()); 38 } 39 40 41 virtual const char *getPassName() const { 42 return "Path Profiler Verifier"; 43 } 44 45 // The verifier requires the path profile and edge profile. 46 virtual void getAnalysisUsage(AnalysisUsage& AU) const; 47 }; 48 } 49 50 static cl::opt<std::string> 51 EdgeProfileFilename("path-profile-verifier-file", 52 cl::init("edgefrompath.llvmprof.out"), 53 cl::value_desc("filename"), 54 cl::desc("Edge profile file generated by -path-profile-verifier"), 55 cl::Hidden); 56 57 char PathProfileVerifier::ID = 0; 58 INITIALIZE_PASS(PathProfileVerifier, "path-profile-verifier", 59 "Compare the path profile derived edge profile against the " 60 "edge profile.", true, true) 61 62 ModulePass *llvm::createPathProfileVerifierPass() { 63 return new PathProfileVerifier(); 64 } 65 66 // The verifier requires the path profile and edge profile. 67 void PathProfileVerifier::getAnalysisUsage(AnalysisUsage& AU) const { 68 AU.addRequired<PathProfileInfo>(); 69 AU.addPreserved<PathProfileInfo>(); 70 } 71 72 typedef std::map<unsigned, unsigned> DuplicateToIndexMap; 73 typedef std::map<BasicBlock*,DuplicateToIndexMap> BlockToDuplicateMap; 74 typedef std::map<BasicBlock*,BlockToDuplicateMap> NestedBlockToIndexMap; 75 76 // the verifier iterates through each path to gather the total 77 // number of edge frequencies 78 bool PathProfileVerifier::runOnModule (Module &M) { 79 PathProfileInfo& pathProfileInfo = getAnalysis<PathProfileInfo>(); 80 81 // setup a data structure to map path edges which index an 82 // array of edge counters 83 NestedBlockToIndexMap arrayMap; 84 unsigned i = 0; 85 for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) { 86 if (F->isDeclaration()) continue; 87 88 arrayMap[0][F->begin()][0] = i++; 89 90 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) { 91 TerminatorInst *TI = BB->getTerminator(); 92 93 unsigned duplicate = 0; 94 BasicBlock* prev = 0; 95 for (unsigned s = 0, e = TI->getNumSuccessors(); s != e; 96 prev = TI->getSuccessor(s), ++s) { 97 if (prev == TI->getSuccessor(s)) 98 duplicate++; 99 else duplicate = 0; 100 101 arrayMap[BB][TI->getSuccessor(s)][duplicate] = i++; 102 } 103 } 104 } 105 106 std::vector<unsigned> edgeArray(i); 107 108 // iterate through each path and increment the edge counters as needed 109 for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F) { 110 if (F->isDeclaration()) continue; 111 112 pathProfileInfo.setCurrentFunction(F); 113 114 DEBUG(dbgs() << "function '" << F->getName() << "' ran " 115 << pathProfileInfo.pathsRun() 116 << "/" << pathProfileInfo.getPotentialPathCount() 117 << " potential paths\n"); 118 119 for( ProfilePathIterator nextPath = pathProfileInfo.pathBegin(), 120 endPath = pathProfileInfo.pathEnd(); 121 nextPath != endPath; nextPath++ ) { 122 ProfilePath* currentPath = nextPath->second; 123 124 ProfilePathEdgeVector* pev = currentPath->getPathEdges(); 125 DEBUG(dbgs () << "path #" << currentPath->getNumber() << ": " 126 << currentPath->getCount() << "\n"); 127 // setup the entry edge (normally path profiling doesn't care about this) 128 if (currentPath->getFirstBlockInPath() == &F->getEntryBlock()) 129 edgeArray[arrayMap[0][currentPath->getFirstBlockInPath()][0]] 130 += currentPath->getCount(); 131 132 for( ProfilePathEdgeIterator nextEdge = pev->begin(), 133 endEdge = pev->end(); nextEdge != endEdge; nextEdge++ ) { 134 if (nextEdge != pev->begin()) 135 DEBUG(dbgs() << " :: "); 136 137 BasicBlock* source = nextEdge->getSource(); 138 BasicBlock* target = nextEdge->getTarget(); 139 unsigned duplicateNumber = nextEdge->getDuplicateNumber(); 140 DEBUG(dbgs () << source->getNameStr() << " --{" << duplicateNumber 141 << "}--> " << target->getNameStr()); 142 143 // Ensure all the referenced edges exist 144 // TODO: make this a separate function 145 if( !arrayMap.count(source) ) { 146 errs() << " error [" << F->getNameStr() << "()]: source '" 147 << source->getNameStr() 148 << "' does not exist in the array map.\n"; 149 } else if( !arrayMap[source].count(target) ) { 150 errs() << " error [" << F->getNameStr() << "()]: target '" 151 << target->getNameStr() 152 << "' does not exist in the array map.\n"; 153 } else if( !arrayMap[source][target].count(duplicateNumber) ) { 154 errs() << " error [" << F->getNameStr() << "()]: edge " 155 << source->getNameStr() << " -> " << target->getNameStr() 156 << " duplicate number " << duplicateNumber 157 << " does not exist in the array map.\n"; 158 } else { 159 edgeArray[arrayMap[source][target][duplicateNumber]] 160 += currentPath->getCount(); 161 } 162 } 163 164 DEBUG(errs() << "\n"); 165 166 delete pev; 167 } 168 } 169 170 std::string errorInfo; 171 std::string filename = EdgeProfileFilename; 172 173 // Open a handle to the file 174 FILE* edgeFile = fopen(filename.c_str(),"wb"); 175 176 if (!edgeFile) { 177 errs() << "error: unable to open file '" << filename << "' for output.\n"; 178 return false; 179 } 180 181 errs() << "Generating edge profile '" << filename << "' ...\n"; 182 183 // write argument info 184 unsigned type = ArgumentInfo; 185 unsigned num = pathProfileInfo.argList.size(); 186 int zeros = 0; 187 188 fwrite(&type,sizeof(unsigned),1,edgeFile); 189 fwrite(&num,sizeof(unsigned),1,edgeFile); 190 fwrite(pathProfileInfo.argList.c_str(),1,num,edgeFile); 191 if (num&3) 192 fwrite(&zeros, 1, 4-(num&3), edgeFile); 193 194 type = EdgeInfo; 195 num = edgeArray.size(); 196 fwrite(&type,sizeof(unsigned),1,edgeFile); 197 fwrite(&num,sizeof(unsigned),1,edgeFile); 198 199 // write each edge to the file 200 for( std::vector<unsigned>::iterator s = edgeArray.begin(), 201 e = edgeArray.end(); s != e; s++) 202 fwrite(&*s, sizeof (unsigned), 1, edgeFile); 203 204 fclose (edgeFile); 205 206 return true; 207 } 208
