LLVM API Documentation
00001 //===-- llvm/ADT/Statistic.h - Easy way to expose stats ---------*- C++ -*-===// 00002 // 00003 // The LLVM Compiler Infrastructure 00004 // 00005 // This file was developed by the LLVM research group and is distributed under 00006 // the University of Illinois Open Source License. See LICENSE.TXT for details. 00007 // 00008 //===----------------------------------------------------------------------===// 00009 // 00010 // This file defines the 'Statistic' class, which is designed to be an easy way 00011 // to expose various success metrics from passes. These statistics are printed 00012 // at the end of a run, when the -stats command line option is enabled on the 00013 // command line. 00014 // 00015 // This is useful for reporting information like the number of instructions 00016 // simplified, optimized or removed by various transformations, like this: 00017 // 00018 // static Statistic<> NumInstsKilled("gcse", "Number of instructions killed"); 00019 // 00020 // Later, in the code: ++NumInstsKilled; 00021 // 00022 //===----------------------------------------------------------------------===// 00023 00024 #ifndef LLVM_ADT_STATISTIC_H 00025 #define LLVM_ADT_STATISTIC_H 00026 00027 #include <iosfwd> 00028 00029 namespace llvm { 00030 00031 // StatisticBase - Nontemplated base class for Statistic<> class... 00032 class StatisticBase { 00033 const char *Name; 00034 const char *Desc; 00035 static unsigned NumStats; 00036 protected: 00037 StatisticBase(const char *name, const char *desc) : Name(name), Desc(desc) { 00038 ++NumStats; // Keep track of how many stats are created... 00039 } 00040 // Out of line virtual dtor, to give the vtable etc a home. 00041 virtual ~StatisticBase(); 00042 00043 // destroy - Called by subclass dtor so that we can still invoke virtual 00044 // functions on the subclass. 00045 void destroy() const; 00046 00047 // printValue - Overridden by template class to print out the value type... 00048 virtual void printValue(std::ostream &o) const = 0; 00049 00050 // hasSomeData - Return true if some data has been aquired. Avoid printing 00051 // lots of zero counts. 00052 // 00053 virtual bool hasSomeData() const = 0; 00054 }; 00055 00056 // Statistic Class - templated on the data type we are monitoring... 00057 template <typename DataType=unsigned> 00058 class Statistic : private StatisticBase { 00059 DataType Value; 00060 00061 virtual void printValue(std::ostream &o) const { o << Value; } 00062 virtual bool hasSomeData() const { return Value != DataType(); } 00063 public: 00064 // Normal constructor, default initialize data item... 00065 Statistic(const char *name, const char *desc) 00066 : StatisticBase(name, desc), Value(DataType()) {} 00067 00068 // Constructor to provide an initial value... 00069 Statistic(const DataType &Val, const char *name, const char *desc) 00070 : StatisticBase(name, desc), Value(Val) {} 00071 00072 // Print information when destroyed, iff command line option is specified 00073 ~Statistic() { destroy(); } 00074 00075 // Allow use of this class as the value itself... 00076 operator DataType() const { return Value; } 00077 const Statistic &operator=(DataType Val) { Value = Val; return *this; } 00078 const Statistic &operator++() { ++Value; return *this; } 00079 DataType operator++(int) { return Value++; } 00080 const Statistic &operator--() { --Value; return *this; } 00081 DataType operator--(int) { return Value--; } 00082 const Statistic &operator+=(const DataType &V) { Value += V; return *this; } 00083 const Statistic &operator-=(const DataType &V) { Value -= V; return *this; } 00084 const Statistic &operator*=(const DataType &V) { Value *= V; return *this; } 00085 const Statistic &operator/=(const DataType &V) { Value /= V; return *this; } 00086 }; 00087 00088 } // End llvm namespace 00089 00090 #endif