freebsd-dev/contrib/llvm/lib/Support/Statistic.cpp
2017-01-02 21:25:48 +00:00

209 lines
6.4 KiB
C++

//===-- Statistic.cpp - Easy way to expose stats information --------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the 'Statistic' class, which is designed to be an easy
// way to expose various success metrics from passes. These statistics are
// printed at the end of a run, when the -stats command line option is enabled
// on the command line.
//
// This is useful for reporting information like the number of instructions
// simplified, optimized or removed by various transformations, like this:
//
// static Statistic NumInstEliminated("GCSE", "Number of instructions killed");
//
// Later, in the code: ++NumInstEliminated;
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/Mutex.h"
#include "llvm/Support/Timer.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/YAMLTraits.h"
#include <algorithm>
#include <cstring>
using namespace llvm;
/// -stats - Command line option to cause transformations to emit stats about
/// what they did.
///
static cl::opt<bool> Stats("stats",
cl::desc("Enable statistics output from program (available with Asserts)"));
static cl::opt<bool> StatsAsJSON("stats-json",
cl::desc("Display statistics as json data"));
static bool Enabled;
static bool PrintOnExit;
namespace {
/// StatisticInfo - This class is used in a ManagedStatic so that it is created
/// on demand (when the first statistic is bumped) and destroyed only when
/// llvm_shutdown is called. We print statistics from the destructor.
class StatisticInfo {
std::vector<const Statistic*> Stats;
friend void llvm::PrintStatistics();
friend void llvm::PrintStatistics(raw_ostream &OS);
friend void llvm::PrintStatisticsJSON(raw_ostream &OS);
/// Sort statistics by debugtype,name,description.
void sort();
public:
StatisticInfo();
~StatisticInfo();
void addStatistic(const Statistic *S) {
Stats.push_back(S);
}
};
}
static ManagedStatic<StatisticInfo> StatInfo;
static ManagedStatic<sys::SmartMutex<true> > StatLock;
/// RegisterStatistic - The first time a statistic is bumped, this method is
/// called.
void Statistic::RegisterStatistic() {
// If stats are enabled, inform StatInfo that this statistic should be
// printed.
sys::SmartScopedLock<true> Writer(*StatLock);
if (!Initialized) {
if (Stats || Enabled)
StatInfo->addStatistic(this);
TsanHappensBefore(this);
sys::MemoryFence();
// Remember we have been registered.
TsanIgnoreWritesBegin();
Initialized = true;
TsanIgnoreWritesEnd();
}
}
StatisticInfo::StatisticInfo() {
// Ensure timergroup lists are created first so they are destructed after us.
TimerGroup::ConstructTimerLists();
}
// Print information when destroyed, iff command line option is specified.
StatisticInfo::~StatisticInfo() {
if (::Stats || PrintOnExit)
llvm::PrintStatistics();
}
void llvm::EnableStatistics(bool PrintOnExit) {
Enabled = true;
::PrintOnExit = PrintOnExit;
}
bool llvm::AreStatisticsEnabled() {
return Enabled || Stats;
}
void StatisticInfo::sort() {
std::stable_sort(Stats.begin(), Stats.end(),
[](const Statistic *LHS, const Statistic *RHS) {
if (int Cmp = std::strcmp(LHS->getDebugType(), RHS->getDebugType()))
return Cmp < 0;
if (int Cmp = std::strcmp(LHS->getName(), RHS->getName()))
return Cmp < 0;
return std::strcmp(LHS->getDesc(), RHS->getDesc()) < 0;
});
}
void llvm::PrintStatistics(raw_ostream &OS) {
StatisticInfo &Stats = *StatInfo;
// Figure out how long the biggest Value and Name fields are.
unsigned MaxDebugTypeLen = 0, MaxValLen = 0;
for (size_t i = 0, e = Stats.Stats.size(); i != e; ++i) {
MaxValLen = std::max(MaxValLen,
(unsigned)utostr(Stats.Stats[i]->getValue()).size());
MaxDebugTypeLen = std::max(MaxDebugTypeLen,
(unsigned)std::strlen(Stats.Stats[i]->getDebugType()));
}
Stats.sort();
// Print out the statistics header...
OS << "===" << std::string(73, '-') << "===\n"
<< " ... Statistics Collected ...\n"
<< "===" << std::string(73, '-') << "===\n\n";
// Print all of the statistics.
for (size_t i = 0, e = Stats.Stats.size(); i != e; ++i)
OS << format("%*u %-*s - %s\n",
MaxValLen, Stats.Stats[i]->getValue(),
MaxDebugTypeLen, Stats.Stats[i]->getDebugType(),
Stats.Stats[i]->getDesc());
OS << '\n'; // Flush the output stream.
OS.flush();
}
void llvm::PrintStatisticsJSON(raw_ostream &OS) {
StatisticInfo &Stats = *StatInfo;
Stats.sort();
// Print all of the statistics.
OS << "{\n";
const char *delim = "";
for (const Statistic *Stat : Stats.Stats) {
OS << delim;
assert(!yaml::needsQuotes(Stat->getDebugType()) &&
"Statistic group/type name is simple.");
assert(!yaml::needsQuotes(Stat->getName()) && "Statistic name is simple");
OS << "\t\"" << Stat->getDebugType() << '.' << Stat->getName() << "\": "
<< Stat->getValue();
delim = ",\n";
}
// Print timers.
TimerGroup::printAllJSONValues(OS, delim);
OS << "\n}\n";
OS.flush();
}
void llvm::PrintStatistics() {
#if !defined(NDEBUG) || defined(LLVM_ENABLE_STATS)
StatisticInfo &Stats = *StatInfo;
// Statistics not enabled?
if (Stats.Stats.empty()) return;
// Get the stream to write to.
std::unique_ptr<raw_ostream> OutStream = CreateInfoOutputFile();
if (StatsAsJSON)
PrintStatisticsJSON(*OutStream);
else
PrintStatistics(*OutStream);
#else
// Check if the -stats option is set instead of checking
// !Stats.Stats.empty(). In release builds, Statistics operators
// do nothing, so stats are never Registered.
if (Stats) {
// Get the stream to write to.
std::unique_ptr<raw_ostream> OutStream = CreateInfoOutputFile();
(*OutStream) << "Statistics are disabled. "
<< "Build with asserts or with -DLLVM_ENABLE_STATS\n";
}
#endif
}