llvm-project/llvm/lib/Support/Statistic.cpp

//===-- StatisticReporter.cpp - Easy way to expose stats information -------==//
//
// 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 "Support/StatisticReporter.h"
#include "Support/CommandLine.h"
#include <iostream>

bool DebugFlag;  // DebugFlag - Exported boolean set by the -debug option

// -stats - Command line option to cause transformations to emit stats about
// what they did.
//
static cl::opt<bool>
Enabled("stats", cl::desc("Enable statistics output from program"));

// -debug - Command line option to enable the DEBUG statements in the passes.
static cl::opt<bool, true>
Debug("debug", cl::desc("Enable debug output"), cl::Hidden,
      cl::location(DebugFlag));

// Print information when destroyed, iff command line option is specified
void StatisticBase::destroy() const {
  if (Enabled && hasSomeData()) {
    std::cerr.width(7);
    printValue(std::cerr);
    std::cerr.width(0);
    std::cerr << "\t" << Name << "\n";
  }
}