LCOV - code coverage report
Current view: top level - include/llvm/Support - Chrono.h (source / functions) Hit Total Coverage
Test: llvm-toolchain.info Lines: 10 10 100.0 %
Date: 2018-06-17 00:07:59 Functions: 24 24 100.0 %
Legend: Lines: hit not hit

          Line data    Source code
       1             : //===- llvm/Support/Chrono.h - Utilities for Timing Manipulation-*- C++ -*-===//
       2             : //
       3             : //                     The LLVM Compiler Infrastructure
       4             : //
       5             : // This file is distributed under the University of Illinois Open Source
       6             : // License. See LICENSE.TXT for details.
       7             : //
       8             : //===----------------------------------------------------------------------===//
       9             : 
      10             : #ifndef LLVM_SUPPORT_CHRONO_H
      11             : #define LLVM_SUPPORT_CHRONO_H
      12             : 
      13             : #include "llvm/Support/Compiler.h"
      14             : #include "llvm/Support/FormatProviders.h"
      15             : 
      16             : #include <chrono>
      17             : #include <ctime>
      18             : 
      19             : namespace llvm {
      20             : 
      21             : class raw_ostream;
      22             : 
      23             : namespace sys {
      24             : 
      25             : /// A time point on the system clock. This is provided for two reasons:
      26             : /// - to insulate us agains subtle differences in behavoir to differences in
      27             : ///   system clock precision (which is implementation-defined and differs between
      28             : ///   platforms).
      29             : /// - to shorten the type name
      30             : /// The default precision is nanoseconds. If need a specific precision specify
      31             : /// it explicitly. If unsure, use the default. If you need a time point on a
      32             : /// clock other than the system_clock, use std::chrono directly.
      33             : template <typename D = std::chrono::nanoseconds>
      34             : using TimePoint = std::chrono::time_point<std::chrono::system_clock, D>;
      35             : 
      36             : /// Convert a TimePoint to std::time_t
      37             : LLVM_ATTRIBUTE_ALWAYS_INLINE inline std::time_t toTimeT(TimePoint<> TP) {
      38             :   using namespace std::chrono;
      39             :   return system_clock::to_time_t(
      40             :       time_point_cast<system_clock::time_point::duration>(TP));
      41             : }
      42             : 
      43             : /// Convert a std::time_t to a TimePoint
      44             : LLVM_ATTRIBUTE_ALWAYS_INLINE inline TimePoint<std::chrono::seconds>
      45             : toTimePoint(std::time_t T) {
      46             :   using namespace std::chrono;
      47             :   return time_point_cast<seconds>(system_clock::from_time_t(T));
      48             : }
      49             : 
      50             : } // namespace sys
      51             : 
      52             : raw_ostream &operator<<(raw_ostream &OS, sys::TimePoint<> TP);
      53             : 
      54             : /// Format provider for TimePoint<>
      55             : ///
      56             : /// The options string is a strftime format string, with extensions:
      57             : ///   - %L is millis: 000-999
      58             : ///   - %f is micros: 000000-999999
      59             : ///   - %N is nanos: 000000000 - 999999999
      60             : ///
      61             : /// If no options are given, the default format is "%Y-%m-%d %H:%M:%S.%N".
      62             : template <>
      63             : struct format_provider<sys::TimePoint<>> {
      64             :   static void format(const sys::TimePoint<> &TP, llvm::raw_ostream &OS,
      65             :                      StringRef Style);
      66             : };
      67             : 
      68             : /// Implementation of format_provider<T> for duration types.
      69             : ///
      70             : /// The options string of a duration  type has the grammar:
      71             : ///
      72             : ///   duration_options  ::= [unit][show_unit [number_options]]
      73             : ///   unit              ::= `h`|`m`|`s`|`ms|`us`|`ns`
      74             : ///   show_unit         ::= `+` | `-`
      75             : ///   number_options    ::= options string for a integral or floating point type
      76             : ///
      77             : ///   Examples
      78             : ///   =================================
      79             : ///   |  options  | Input | Output    |
      80             : ///   =================================
      81             : ///   | ""        | 1s    | 1 s       |
      82             : ///   | "ms"      | 1s    | 1000 ms   |
      83             : ///   | "ms-"     | 1s    | 1000      |
      84             : ///   | "ms-n"    | 1s    | 1,000     |
      85             : ///   | ""        | 1.0s  | 1.00 s    |
      86             : ///   =================================
      87             : ///
      88             : ///  If the unit of the duration type is not one of the units specified above,
      89             : ///  it is still possible to format it, provided you explicitly request a
      90             : ///  display unit or you request that the unit is not displayed.
      91             : 
      92             : namespace detail {
      93             : template <typename Period> struct unit { static const char value[]; };
      94             : template <typename Period> const char unit<Period>::value[] = "";
      95             : 
      96             : template <> struct unit<std::ratio<3600>> { static const char value[]; };
      97             : template <> struct unit<std::ratio<60>> { static const char value[]; };
      98             : template <> struct unit<std::ratio<1>> { static const char value[]; };
      99             : template <> struct unit<std::milli> { static const char value[]; };
     100             : template <> struct unit<std::micro> { static const char value[]; };
     101             : template <> struct unit<std::nano> { static const char value[]; };
     102             : } // namespace detail
     103             : 
     104             : template <typename Rep, typename Period>
     105             : struct format_provider<std::chrono::duration<Rep, Period>> {
     106             : private:
     107             :   typedef std::chrono::duration<Rep, Period> Dur;
     108             :   typedef typename std::conditional<
     109             :       std::chrono::treat_as_floating_point<Rep>::value, double, intmax_t>::type
     110             :       InternalRep;
     111             : 
     112             :   template <typename AsPeriod> static InternalRep getAs(const Dur &D) {
     113             :     using namespace std::chrono;
     114             :     return duration_cast<duration<InternalRep, AsPeriod>>(D).count();
     115             :   }
     116             : 
     117          72 :   static std::pair<InternalRep, StringRef> consumeUnit(StringRef &Style,
     118             :                                                         const Dur &D) {
     119             :     using namespace std::chrono;
     120             :     if (Style.consume_front("ns"))
     121             :       return {getAs<std::nano>(D), "ns"};
     122             :     if (Style.consume_front("us"))
     123             :       return {getAs<std::micro>(D), "us"};
     124             :     if (Style.consume_front("ms"))
     125             :       return {getAs<std::milli>(D), "ms"};
     126             :     if (Style.consume_front("s"))
     127             :       return {getAs<std::ratio<1>>(D), "s"};
     128             :     if (Style.consume_front("m"))
     129             :       return {getAs<std::ratio<60>>(D), "m"};
     130             :     if (Style.consume_front("h"))
     131             :       return {getAs<std::ratio<3600>>(D), "h"};
     132             :     return {D.count(), detail::unit<Period>::value};
     133             :   }
     134             : 
     135          72 :   static bool consumeShowUnit(StringRef &Style) {
     136          72 :     if (Style.empty())
     137             :       return true;
     138             :     if (Style.consume_front("-"))
     139             :       return false;
     140             :     if (Style.consume_front("+"))
     141             :       return true;
     142             :     assert(0 && "Unrecognised duration format");
     143             :     return true;
     144             :   }
     145             : 
     146             : public:
     147          72 :   static void format(const Dur &D, llvm::raw_ostream &Stream, StringRef Style) {
     148             :     InternalRep count;
     149             :     StringRef unit;
     150         144 :     std::tie(count, unit) = consumeUnit(Style, D);
     151          72 :     bool show_unit = consumeShowUnit(Style);
     152             : 
     153          72 :     format_provider<InternalRep>::format(count, Stream, Style);
     154             : 
     155          72 :     if (show_unit) {
     156             :       assert(!unit.empty());
     157          15 :       Stream << " " << unit;
     158             :     }
     159          72 :   }
     160             : };
     161             : 
     162             : } // namespace llvm
     163             : 
     164             : #endif // LLVM_SUPPORT_CHRONO_H

Generated by: LCOV version 1.13