1//===-- Timer.h -------------------------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#ifndef LLDB_UTILITY_TIMER_H
10#define LLDB_UTILITY_TIMER_H
11
12#include "lldb/lldb-defines.h"
13#include "llvm/Support/Chrono.h"
14#include <atomic>
15#include <cstdint>
16
17namespace lldb_private {
18class Stream;
19
20/// \class Timer Timer.h "lldb/Utility/Timer.h"
21/// A timer class that simplifies common timing metrics.
22
23class Timer {
24public:
25  class Category {
26  public:
27    explicit Category(const char *category_name);
28    llvm::StringRef GetName() { return m_name; }
29
30  private:
31    friend class Timer;
32    const char *m_name;
33    std::atomic<uint64_t> m_nanos;
34    std::atomic<uint64_t> m_nanos_total;
35    std::atomic<uint64_t> m_count;
36    std::atomic<Category *> m_next;
37
38    Category(const Category &) = delete;
39    const Category &operator=(const Category &) = delete;
40  };
41
42  /// Default constructor.
43  Timer(Category &category, const char *format, ...)
44#if !defined(_MSC_VER)
45  // MSVC appears to have trouble recognizing the this argument in the constructor.
46      __attribute__((format(printf, 3, 4)))
47#endif
48    ;
49
50  /// Destructor
51  ~Timer();
52
53  void Dump();
54
55  static void SetDisplayDepth(uint32_t depth);
56
57  static void SetQuiet(bool value);
58
59  static void DumpCategoryTimes(Stream &s);
60
61  static void ResetCategoryTimes();
62
63protected:
64  using TimePoint = std::chrono::steady_clock::time_point;
65  void ChildDuration(TimePoint::duration dur) { m_child_duration += dur; }
66
67  Category &m_category;
68  TimePoint m_total_start;
69  TimePoint::duration m_child_duration{0};
70
71  static std::atomic<bool> g_quiet;
72  static std::atomic<unsigned> g_display_depth;
73
74private:
75  Timer(const Timer &) = delete;
76  const Timer &operator=(const Timer &) = delete;
77};
78
79} // namespace lldb_private
80
81// Use a format string because LLVM_PRETTY_FUNCTION might not be a string
82// literal.
83#define LLDB_SCOPED_TIMER()                                                    \
84  static ::lldb_private::Timer::Category _cat(LLVM_PRETTY_FUNCTION);           \
85  ::lldb_private::Timer _scoped_timer(_cat, "%s", LLVM_PRETTY_FUNCTION)
86#define LLDB_SCOPED_TIMERF(...)                                                \
87  static ::lldb_private::Timer::Category _cat(LLVM_PRETTY_FUNCTION);           \
88  ::lldb_private::Timer _scoped_timer(_cat, __VA_ARGS__)
89
90#endif // LLDB_UTILITY_TIMER_H
91