Simplify memory management with std::unique_ptr.

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

diff --git a/include/llvm/ADT/Statistic.h b/include/llvm/ADT/Statistic.h
index 4bf47640eeed73bbab5f4ef55ebbee9ef0bdd442..7c84e3ef6b4dc95464d77d14d7300c5a447e8b38 100644 (file)
--- a/include/llvm/ADT/Statistic.h
+++ b/include/llvm/ADT/Statistic.h
@@ -2,8 +2,8 @@
 //
 //                     The LLVM Compiler Infrastructure
 //
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
@@ -26,50 +26,160 @@
 #ifndef LLVM_ADT_STATISTIC_H
 #define LLVM_ADT_STATISTIC_H
 
+#include "llvm/Support/Atomic.h"
+#include "llvm/Support/Valgrind.h"
+#include <memory>
+
 namespace llvm {
+class raw_ostream;
+class raw_fd_ostream;
 
-class StatisticBase {
+class Statistic {
 public:
   const char *Name;
   const char *Desc;
-  unsigned Value : 31;
-  bool Initialized : 1;
+  volatile llvm::sys::cas_flag Value;
+  bool Initialized;
 
-  unsigned getValue() const { return Value; }
+  llvm::sys::cas_flag getValue() const { return Value; }
   const char *getName() const { return Name; }
   const char *getDesc() const { return Desc; }
-  
+
+  /// 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 = false;
+  }
+
   // Allow use of this class as the value itself.
   operator unsigned() const { return Value; }
-  const StatisticBase &operator=(unsigned Val) { Value = Val; return init(); }
-  const StatisticBase &operator++() { ++Value; return init(); }
-  unsigned operator++(int) { init(); return Value++; }
-  const StatisticBase &operator--() { --Value; return init(); }
-  unsigned operator--(int) { init(); return Value--; }
-  const StatisticBase &operator+=(const unsigned &V) {Value += V;return init();}
-  const StatisticBase &operator-=(const unsigned &V) {Value -= V;return init();}
-  const StatisticBase &operator*=(const unsigned &V) {Value *= V;return init();}
-  const StatisticBase &operator/=(const unsigned &V) {Value /= V;return init();}
-  
-private:
-  StatisticBase &init() {
-    if (!Initialized) RegisterStatistic();
+
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_STATS)
+   const Statistic &operator=(unsigned Val) {
+    Value = Val;
+    return init();
+  }
+
+  const Statistic &operator++() {
+    // FIXME: This function and all those that follow carefully use an
+    // atomic operation to update the value safely in the presence of
+    // concurrent accesses, but not to read the return value, so the
+    // return value is not thread safe.
+    sys::AtomicIncrement(&Value);
+    return init();
+  }
+
+  unsigned operator++(int) {
+    init();
+    unsigned OldValue = Value;
+    sys::AtomicIncrement(&Value);
+    return OldValue;
+  }
+
+  const Statistic &operator--() {
+    sys::AtomicDecrement(&Value);
+    return init();
+  }
+
+  unsigned operator--(int) {
+    init();
+    unsigned OldValue = Value;
+    sys::AtomicDecrement(&Value);
+    return OldValue;
+  }
+
+  const Statistic &operator+=(const unsigned &V) {
+    if (!V) return *this;
+    sys::AtomicAdd(&Value, V);
+    return init();
+  }
+
+  const Statistic &operator-=(const unsigned &V) {
+    if (!V) return *this;
+    sys::AtomicAdd(&Value, -V);
+    return init();
+  }
+
+  const Statistic &operator*=(const unsigned &V) {
+    sys::AtomicMul(&Value, V);
+    return init();
+  }
+
+  const Statistic &operator/=(const unsigned &V) {
+    sys::AtomicDiv(&Value, V);
+    return init();
+  }
+
+#else  // Statistics are disabled in release builds.
+
+  const Statistic &operator=(unsigned Val) {
     return *this;
   }
-  void RegisterStatistic();
-};
-  
-struct Statistic : public StatisticBase {
-  Statistic(const char *name, const char *desc) {
-    Name = name; Desc = desc; Value = 0; Initialized = 0;
+
+  const Statistic &operator++() {
+    return *this;
   }
+
+  unsigned operator++(int) {
+    return 0;
+  }
+
+  const Statistic &operator--() {
+    return *this;
+  }
+
+  unsigned operator--(int) {
+    return 0;
+  }
+
+  const Statistic &operator+=(const unsigned &V) {
+    return *this;
+  }
+
+  const Statistic &operator-=(const unsigned &V) {
+    return *this;
+  }
+
+  const Statistic &operator*=(const unsigned &V) {
+    return *this;
+  }
+
+  const Statistic &operator/=(const unsigned &V) {
+    return *this;
+  }
+
+#endif  // !defined(NDEBUG) || defined(LLVM_ENABLE_STATS)
+
+protected:
+  Statistic &init() {
+    bool tmp = Initialized;
+    sys::MemoryFence();
+    if (!tmp) RegisterStatistic();
+    TsanHappensAfter(this);
+    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 StatisticBase VARNAME = { DEBUG_TYPE, DESC, 0, 0 }
+  static llvm::Statistic VARNAME = { DEBUG_TYPE, DESC, 0, 0 }
+
+/// \brief Enable the collection and printing of statistics.
+void EnableStatistics();
+
+/// \brief Check if statistics are enabled.
+bool AreStatisticsEnabled();
+
+/// \brief Return a file stream to print our output on.
+std::unique_ptr<raw_fd_ostream> CreateInfoOutputFile();
+
+/// \brief Print statistics to the file returned by CreateInfoOutputFile().
+void PrintStatistics();
+
+/// \brief Print statistics to the given output stream.
+void PrintStatistics(raw_ostream &OS);
 
 } // End llvm namespace