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 virtual ~StatisticBase() {} 00041 00042 // destroy - Called by subclass dtor so that we can still invoke virtual 00043 // functions on the subclass. 00044 void destroy() const; 00045 00046 // printValue - Overridden by template class to print out the value type... 00047 virtual void printValue(std::ostream &o) const = 0; 00048 00049 // hasSomeData - Return true if some data has been aquired. Avoid printing 00050 // lots of zero counts. 00051 // 00052 virtual bool hasSomeData() const = 0; 00053 }; 00054 00055 // Statistic Class - templated on the data type we are monitoring... 00056 template <typename DataType=unsigned> 00057 class Statistic : private StatisticBase { 00058 DataType Value; 00059 00060 virtual void printValue(std::ostream &o) const { o << Value; } 00061 virtual bool hasSomeData() const { return Value != DataType(); } 00062 public: 00063 // Normal constructor, default initialize data item... 00064 Statistic(const char *name, const char *desc) 00065 : StatisticBase(name, desc), Value(DataType()) {} 00066 00067 // Constructor to provide an initial value... 00068 Statistic(const DataType &Val, const char *name, const char *desc) 00069 : StatisticBase(name, desc), Value(Val) {} 00070 00071 // Print information when destroyed, iff command line option is specified 00072 ~Statistic() { destroy(); } 00073 00074 // Allow use of this class as the value itself... 00075 operator DataType() const { return Value; } 00076 const Statistic &operator=(DataType Val) { Value = Val; return *this; } 00077 const Statistic &operator++() { ++Value; return *this; } 00078 DataType operator++(int) { return Value++; } 00079 const Statistic &operator--() { --Value; return *this; } 00080 DataType operator--(int) { return Value--; } 00081 const Statistic &operator+=(const DataType &V) { Value += V; return *this; } 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 }; 00086 00087 } // End llvm namespace 00088 00089 #endif