Statistic.cpp revision 221345
10Sstevel@tonic-gate//===-- Statistic.cpp - Easy way to expose stats information --------------===// 20Sstevel@tonic-gate// 30Sstevel@tonic-gate// The LLVM Compiler Infrastructure 40Sstevel@tonic-gate// 50Sstevel@tonic-gate// This file is distributed under the University of Illinois Open Source 60Sstevel@tonic-gate// License. See LICENSE.TXT for details. 70Sstevel@tonic-gate// 80Sstevel@tonic-gate//===----------------------------------------------------------------------===// 90Sstevel@tonic-gate// 100Sstevel@tonic-gate// This file implements the 'Statistic' class, which is designed to be an easy 110Sstevel@tonic-gate// way to expose various success metrics from passes. These statistics are 120Sstevel@tonic-gate// printed at the end of a run, when the -stats command line option is enabled 130Sstevel@tonic-gate// on the command line. 140Sstevel@tonic-gate// 150Sstevel@tonic-gate// This is useful for reporting information like the number of instructions 160Sstevel@tonic-gate// simplified, optimized or removed by various transformations, like this: 170Sstevel@tonic-gate// 180Sstevel@tonic-gate// static Statistic NumInstEliminated("GCSE", "Number of instructions killed"); 190Sstevel@tonic-gate// 200Sstevel@tonic-gate// Later, in the code: ++NumInstEliminated; 210Sstevel@tonic-gate// 220Sstevel@tonic-gate//===----------------------------------------------------------------------===// 230Sstevel@tonic-gate 240Sstevel@tonic-gate#include "llvm/ADT/Statistic.h" 250Sstevel@tonic-gate#include "llvm/Support/CommandLine.h" 260Sstevel@tonic-gate#include "llvm/Support/Debug.h" 270Sstevel@tonic-gate#include "llvm/Support/ManagedStatic.h" 280Sstevel@tonic-gate#include "llvm/Support/raw_ostream.h" 290Sstevel@tonic-gate#include "llvm/Support/Mutex.h" 300Sstevel@tonic-gate#include "llvm/ADT/StringExtras.h" 310Sstevel@tonic-gate#include <algorithm> 320Sstevel@tonic-gate#include <cstring> 330Sstevel@tonic-gateusing namespace llvm; 340Sstevel@tonic-gate 350Sstevel@tonic-gate// CreateInfoOutputFile - Return a file stream to print our output on. 360Sstevel@tonic-gatenamespace llvm { extern raw_ostream *CreateInfoOutputFile(); } 370Sstevel@tonic-gate 380Sstevel@tonic-gate/// -stats - Command line option to cause transformations to emit stats about 390Sstevel@tonic-gate/// what they did. 400Sstevel@tonic-gate/// 410Sstevel@tonic-gatestatic cl::opt<bool> 420Sstevel@tonic-gateEnabled("stats", cl::desc("Enable statistics output from program")); 430Sstevel@tonic-gate 440Sstevel@tonic-gate 45namespace { 46/// StatisticInfo - This class is used in a ManagedStatic so that it is created 47/// on demand (when the first statistic is bumped) and destroyed only when 48/// llvm_shutdown is called. We print statistics from the destructor. 49class StatisticInfo { 50 std::vector<const Statistic*> Stats; 51 friend void llvm::PrintStatistics(); 52 friend void llvm::PrintStatistics(raw_ostream &OS); 53public: 54 ~StatisticInfo(); 55 56 void addStatistic(const Statistic *S) { 57 Stats.push_back(S); 58 } 59}; 60} 61 62static ManagedStatic<StatisticInfo> StatInfo; 63static ManagedStatic<sys::SmartMutex<true> > StatLock; 64 65/// RegisterStatistic - The first time a statistic is bumped, this method is 66/// called. 67void Statistic::RegisterStatistic() { 68 // If stats are enabled, inform StatInfo that this statistic should be 69 // printed. 70 sys::SmartScopedLock<true> Writer(*StatLock); 71 if (!Initialized) { 72 if (Enabled) 73 StatInfo->addStatistic(this); 74 75 sys::MemoryFence(); 76 // Remember we have been registered. 77 Initialized = true; 78 } 79} 80 81namespace { 82 83struct NameCompare { 84 bool operator()(const Statistic *LHS, const Statistic *RHS) const { 85 int Cmp = std::strcmp(LHS->getName(), RHS->getName()); 86 if (Cmp != 0) return Cmp < 0; 87 88 // Secondary key is the description. 89 return std::strcmp(LHS->getDesc(), RHS->getDesc()) < 0; 90 } 91}; 92 93} 94 95// Print information when destroyed, iff command line option is specified. 96StatisticInfo::~StatisticInfo() { 97 llvm::PrintStatistics(); 98} 99 100void llvm::EnableStatistics() { 101 Enabled.setValue(true); 102} 103 104bool llvm::AreStatisticsEnabled() { 105 return Enabled; 106} 107 108void llvm::PrintStatistics(raw_ostream &OS) { 109 StatisticInfo &Stats = *StatInfo; 110 111 // Figure out how long the biggest Value and Name fields are. 112 unsigned MaxNameLen = 0, MaxValLen = 0; 113 for (size_t i = 0, e = Stats.Stats.size(); i != e; ++i) { 114 MaxValLen = std::max(MaxValLen, 115 (unsigned)utostr(Stats.Stats[i]->getValue()).size()); 116 MaxNameLen = std::max(MaxNameLen, 117 (unsigned)std::strlen(Stats.Stats[i]->getName())); 118 } 119 120 // Sort the fields by name. 121 std::stable_sort(Stats.Stats.begin(), Stats.Stats.end(), NameCompare()); 122 123 // Print out the statistics header... 124 OS << "===" << std::string(73, '-') << "===\n" 125 << " ... Statistics Collected ...\n" 126 << "===" << std::string(73, '-') << "===\n\n"; 127 128 // Print all of the statistics. 129 for (size_t i = 0, e = Stats.Stats.size(); i != e; ++i) { 130 std::string CountStr = utostr(Stats.Stats[i]->getValue()); 131 OS << std::string(MaxValLen-CountStr.size(), ' ') 132 << CountStr << " " << Stats.Stats[i]->getName() 133 << std::string(MaxNameLen-std::strlen(Stats.Stats[i]->getName()), ' ') 134 << " - " << Stats.Stats[i]->getDesc() << "\n"; 135 } 136 137 OS << '\n'; // Flush the output stream. 138 OS.flush(); 139 140} 141 142void llvm::PrintStatistics() { 143 StatisticInfo &Stats = *StatInfo; 144 145 // Statistics not enabled? 146 if (Stats.Stats.empty()) return; 147 148 // Get the stream to write to. 149 raw_ostream &OutStream = *CreateInfoOutputFile(); 150 PrintStatistics(OutStream); 151 delete &OutStream; // Close the file. 152} 153