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[oota-llvm.git] / include / llvm / ADT / Statistic.h

diff --git a/include/llvm/ADT/Statistic.h b/include/llvm/ADT/Statistic.h
index 15ba9107d9ba0d9f5af0ff799eadacb9bb303714..ec4fdd6009b8bb3d47df05f52e0cb044a8675835 100644 (file)
--- a/include/llvm/ADT/Statistic.h
+++ b/include/llvm/ADT/Statistic.h
@@ -8,81 +8,67 @@
 //===----------------------------------------------------------------------===//
 //
 // This file defines 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.
+// to expose various metrics from passes.  These statistics are printed at the
+// end of a run (from llvm_shutdown), when the -stats command line option is
+// passed 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<> NumInstsKilled("gcse", "Number of instructions killed");
+// static Statistic NumInstsKilled("gcse", "Number of instructions killed");
 //
 // Later, in the code: ++NumInstsKilled;
 //
+// NOTE: Statistics *must* be declared as global variables.
+//
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_ADT_STATISTIC_H
 #define LLVM_ADT_STATISTIC_H
 
-#include <iostream>
-
 namespace llvm {
 
-// StatisticBase - Nontemplated base class for Statistic<> class...
-class StatisticBase {
+class Statistic {
+public:
   const char *Name;
   const char *Desc;
-  static unsigned NumStats;
-protected:
-  StatisticBase(const char *name, const char *desc) : Name(name), Desc(desc) {
-    ++NumStats;  // Keep track of how many stats are created...
-  }
-  virtual ~StatisticBase() {}
-
-  // destroy - Called by subclass dtor so that we can still invoke virtual
-  // functions on the subclass.
-  void destroy() const;
+  unsigned Value : 31;
+  bool Initialized : 1;
 
-  // printValue - Overridden by template class to print out the value type...
-  virtual void printValue(std::ostream &o) const = 0;
-
-  // hasSomeData - Return true if some data has been aquired.  Avoid printing
-  // lots of zero counts.
-  //
-  virtual bool hasSomeData() const = 0;
-};
+  unsigned getValue() const { return Value; }
+  const char *getName() const { return Name; }
+  const char *getDesc() const { return Desc; }
 
-// Statistic Class - templated on the data type we are monitoring...
-template <typename DataType=unsigned>
-class Statistic : private StatisticBase {
-  DataType Value;
-
-  virtual void printValue(std::ostream &o) const { o << Value; }
-  virtual bool hasSomeData() const { return Value != DataType(); }
-public:
-  // Normal constructor, default initialize data item...
-  Statistic(const char *name, const char *desc)
-    : StatisticBase(name, desc), Value(DataType()) {}
-
-  // Constructor to provide an initial value...
-  Statistic(const DataType &Val, const char *name, const char *desc)
-    : StatisticBase(name, desc), Value(Val) {}
-
-  // Print information when destroyed, iff command line option is specified
-  ~Statistic() { destroy(); }
+  /// construct - This should only be called for non-global statistics.
+  void construct(const char *name, const char *desc) {
+    Name = name; Desc = desc;
+    Value = 0; Initialized = 0;
+  }
 
-  // Allow use of this class as the value itself...
-  operator DataType() const { return Value; }
-  const Statistic &operator=(DataType Val) { Value = Val; return *this; }
-  const Statistic &operator++() { ++Value; return *this; }
-  DataType operator++(int) { return Value++; }
-  const Statistic &operator--() { --Value; return *this; }
-  DataType operator--(int) { return Value--; }
-  const Statistic &operator+=(const DataType &V) { Value += V; return *this; }
-  const Statistic &operator-=(const DataType &V) { Value -= V; return *this; }
-  const Statistic &operator*=(const DataType &V) { Value *= V; return *this; }
-  const Statistic &operator/=(const DataType &V) { Value /= V; return *this; }
+  // Allow use of this class as the value itself.
+  operator unsigned() const { return Value; }
+  const Statistic &operator=(unsigned Val) { Value = Val; return init(); }
+  const Statistic &operator++() { ++Value; return init(); }
+  unsigned operator++(int) { init(); return Value++; }
+  const Statistic &operator--() { --Value; return init(); }
+  unsigned operator--(int) { init(); return Value--; }
+  const Statistic &operator+=(const unsigned &V) { Value += V; return init(); }
+  const Statistic &operator-=(const unsigned &V) { Value -= V; return init(); }
+  const Statistic &operator*=(const unsigned &V) { Value *= V; return init(); }
+  const Statistic &operator/=(const unsigned &V) { Value /= V; return init(); }
+  
+protected:
+  Statistic &init() {
+    if (!Initialized) RegisterStatistic();
+    return *this;
+  }
+  void RegisterStatistic();
 };
+  
+// STATISTIC - A macro to make definition of statistics really simple.  This
+// automatically passes the DEBUG_TYPE of the file into the statistic.
+#define STATISTIC(VARNAME, DESC) \
+  static Statistic VARNAME = { DEBUG_TYPE, DESC, 0, 0 }
 
 } // End llvm namespace