Revert "Add Chrono.h - std::chrono support header"

This reverts commit r284590 as it fails on the mingw buildbot. I think I know the
fix, but I cannot test it right now. Will reapply when I verify it works ok.

This reverts r284590.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284615 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Support/Chrono.h

@@ -1,55 +0,0 @@
-//===- llvm/Support/Chrono.h - Utilities for Timing Manipulation-*- C++ -*-===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_SUPPORT_CHRONO_H
-#define LLVM_SUPPORT_CHRONO_H
-
-#include "llvm/Support/Compiler.h"
-
-#include <chrono>
-#include <ctime>
-
-namespace llvm {
-
-class raw_ostream;
-
-namespace sys {
-
-/// A time point on the system clock. This is provided for two reasons:
-/// - to insulate us agains subtle differences in behavoir to differences in
-///   system clock precision (which is implementation-defined and differs between
-///   platforms).
-/// - to shorten the type name
-/// The default precision is nanoseconds. If need a specific precision specify
-/// it explicitly. If unsure, use the default. If you need a time point on a
-/// clock other than the system_clock, use std::chrono directly.
-template <typename D = std::chrono::nanoseconds>
-using TimePoint = std::chrono::time_point<std::chrono::system_clock, D>;
-
-/// Convert a TimePoint to std::time_t
-LLVM_ATTRIBUTE_ALWAYS_INLINE inline std::time_t toTimeT(TimePoint<> TP) {
-  using namespace std::chrono;
-  return system_clock::to_time_t(
-      time_point_cast<system_clock::time_point::duration>(TP));
-}
-
-/// Convert a std::time_t to a TimePoint
-LLVM_ATTRIBUTE_ALWAYS_INLINE inline TimePoint<std::chrono::seconds>
-toTimePoint(std::time_t T) {
-  using namespace std::chrono;
-  return time_point_cast<seconds>(system_clock::from_time_t(T));
-}
-
-} // namespace sys
-
-raw_ostream &operator<<(raw_ostream &OS, sys::TimePoint<> TP);
-
-} // namespace llvm
-
-#endif // LLVM_SUPPORT_CHRONO_H

include/llvm/Support/TimeValue.h

@@ -14,7 +14,6 @@
 #ifndef LLVM_SUPPORT_TIMEVALUE_H
 #define LLVM_SUPPORT_TIMEVALUE_H
 
-#include "llvm/Support/Chrono.h"
 #include "llvm/Support/DataTypes.h"
 #include <string>
 
@@ -113,11 +112,6 @@ namespace sys {
       this->normalize();
     }
 
-    template<typename D>
-    TimeValue(TimePoint<D> TP)
-        : seconds_(sys::toTimeT(TP) + PosixZeroTimeSeconds),
-          nanos_((TimePoint<>(TP).time_since_epoch() % std::chrono::seconds(1)).count()) {}
-
     /// This is a static constructor that returns a TimeValue that represents
     /// the current time.
     /// @brief Creates a TimeValue with the current time (UTC).
@@ -127,11 +121,6 @@ namespace sys {
   /// @name Operators
   /// @{
   public:
-    operator TimePoint<>() const {
-      return toTimePoint(seconds_ - PosixZeroTimeSeconds) +
-             std::chrono::nanoseconds(nanos_);
-    }
-
     /// Add \p that to \p this.
     /// @returns this
     /// @brief Incrementing assignment operator.

lib/Support/CMakeLists.txt

@@ -37,7 +37,6 @@ add_llvm_library(LLVMSupport
   BranchProbability.cpp
   CachePruning.cpp
   circular_raw_ostream.cpp
-  Chrono.cpp
   COM.cpp
   CommandLine.cpp
   Compression.cpp

lib/Support/Chrono.cpp

@@ -1,47 +0,0 @@
-//===- Support/Chrono.cpp - Utilities for Timing Manipulation ---*- C++ -*-===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Support/Chrono.h"
-#include "llvm/Config/config.h"
-#include "llvm/Support/Format.h"
-#include "llvm/Support/raw_ostream.h"
-
-namespace llvm {
-
-using namespace sys;
-
-static inline struct tm getStructTM(TimePoint<> TP) {
-  struct tm Storage;
-  std::time_t OurTime = toTimeT(TP);
-
-#if defined(LLVM_ON_UNIX)
-  struct tm *LT = ::localtime_r(&OurTime, &Storage);
-  assert(LT);
-  (void)LT;
-#endif
-#if defined(LLVM_ON_WIN32)
-  int Error = ::_localtime64_s(&Storage, &OurTime);
-  assert(!Error);
-  (void)Error;
-#endif
-
-  return Storage;
-}
-
-raw_ostream &operator<<(raw_ostream &OS, TimePoint<> TP) {
-  struct tm LT = getStructTM(TP);
-  char Buffer[sizeof("YYYY-MM-DD HH:MM:SS")];
-  strftime(Buffer, sizeof(Buffer), "%Y-%m-%d %H:%M:%S", &LT);
-  return OS << Buffer << '.'
-            << format("%.9lu",
-                      long((TP.time_since_epoch() % std::chrono::seconds(1))
-                               .count()));
-}
-
-} // namespace llvm

lib/Support/TimeValue.cpp

@@ -12,8 +12,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Support/TimeValue.h"
-#include "llvm/Support/Chrono.h"
-#include "llvm/Support/ScopedPrinter.h"
+#include "llvm/Config/config.h"
 
 namespace llvm {
 
@@ -46,10 +45,12 @@ void TimeValue::normalize() {
   }
 }
 
-std::string TimeValue::str() const { return to_string(TimePoint<>(*this)); }
-
-TimeValue TimeValue::now() {
-  return TimePoint<>(std::chrono::system_clock::now());
-}
-
 } // namespace llvm
+
+/// Include the platform-specific portion of TimeValue class
+#ifdef LLVM_ON_UNIX
+#include "Unix/TimeValue.inc"
+#endif
+#ifdef LLVM_ON_WIN32
+#include "Windows/TimeValue.inc"
+#endif

lib/Support/Unix/TimeValue.inc

@@ -0,0 +1,54 @@
+//===- Unix/TimeValue.cpp - Unix TimeValue Implementation -------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the Unix specific portion of the TimeValue class.
+//
+//===----------------------------------------------------------------------===//
+
+//===----------------------------------------------------------------------===//
+//=== WARNING: Implementation here must contain only generic UNIX code that
+//===          is guaranteed to work on *all* UNIX variants.
+//===----------------------------------------------------------------------===//
+
+#include "Unix.h"
+
+namespace llvm {
+  using namespace sys;
+
+std::string TimeValue::str() const {
+  time_t OurTime = time_t(this->toEpochTime());
+  struct tm Storage;
+  struct tm *LT = ::localtime_r(&OurTime, &Storage);
+  assert(LT);
+  char Buffer1[sizeof("YYYY-MM-DD HH:MM:SS")];
+  strftime(Buffer1, sizeof(Buffer1), "%Y-%m-%d %H:%M:%S", LT);
+  char Buffer2[sizeof("YYYY-MM-DD HH:MM:SS.MMMUUUNNN")];
+  snprintf(Buffer2, sizeof(Buffer2), "%s.%.9u", Buffer1, this->nanoseconds());
+  return std::string(Buffer2);
+}
+
+TimeValue TimeValue::now() {
+  struct timeval the_time;
+  timerclear(&the_time);
+  if (0 != ::gettimeofday(&the_time,nullptr)) {
+    // This is *really* unlikely to occur because the only gettimeofday
+    // errors concern the timezone parameter which we're passing in as 0.
+    // In the unlikely case it does happen, just return MinTime, no error
+    // message needed.
+    return MinTime();
+  }
+
+  return TimeValue(
+    static_cast<TimeValue::SecondsType>( the_time.tv_sec +
+      PosixZeroTimeSeconds ),
+    static_cast<TimeValue::NanoSecondsType>( the_time.tv_usec *
+      NANOSECONDS_PER_MICROSECOND ) );
+}
+
+}

lib/Support/Windows/TimeValue.inc

@@ -0,0 +1,61 @@
+//===- Win32/TimeValue.cpp - Win32 TimeValue Implementation -----*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides the Win32 implementation of the TimeValue class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "WindowsSupport.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/raw_ostream.h"
+#include <cctype>
+#include <time.h>
+
+using namespace llvm;
+using namespace llvm::sys;
+
+//===----------------------------------------------------------------------===//
+//=== WARNING: Implementation here must contain only Win32 specific code.
+//===----------------------------------------------------------------------===//
+
+TimeValue TimeValue::now() {
+  uint64_t ft;
+  GetSystemTimeAsFileTime(reinterpret_cast<FILETIME *>(&ft));
+
+  TimeValue t(0, 0);
+  t.fromWin32Time(ft);
+  return t;
+}
+
+std::string TimeValue::str() const {
+  std::string S;
+  struct tm *LT;
+#ifdef __MINGW32__
+  // Old versions of mingw don't have _localtime64_s. Remove this once we drop support
+  // for them.
+  time_t OurTime = time_t(this->toEpochTime());
+  LT = ::localtime(&OurTime);
+  assert(LT);
+#else
+  struct tm Storage;
+  __time64_t OurTime = this->toEpochTime();
+  int Error = ::_localtime64_s(&Storage, &OurTime);
+  assert(!Error);
+  (void)Error;
+  LT = &Storage;
+#endif
+
+  char Buffer[sizeof("YYYY-MM-DD HH:MM:SS")];
+  strftime(Buffer, sizeof(Buffer), "%Y-%m-%d %H:%M:%S", LT);
+  raw_string_ostream OS(S);
+  OS << format("%s.%.9u", static_cast<const char *>(Buffer),
+               this->nanoseconds());
+  OS.flush();
+  return S;
+}

unittests/Support/CMakeLists.txt

@@ -9,7 +9,6 @@ add_llvm_unittest(SupportTests
   BlockFrequencyTest.cpp
   BranchProbabilityTest.cpp
   Casting.cpp
-  Chrono.cpp
   CommandLineTest.cpp
   CompressionTest.cpp
   ConvertUTFTest.cpp

unittests/Support/Chrono.cpp

@@ -1,79 +0,0 @@
-//===- llvm/unittest/Support/Chrono.cpp - Time utilities tests ------------===//
-//
-//           The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Support/Chrono.h"
-#include "llvm/ADT/SmallVector.h"
-#include "gtest/gtest.h"
-
-using namespace llvm;
-using namespace llvm::sys;
-using namespace std::chrono;
-
-namespace {
-
-TEST(Chrono, TimeTConversion) {
-  EXPECT_EQ(time_t(0), toTimeT(toTimePoint(time_t(0))));
-  EXPECT_EQ(time_t(1), toTimeT(toTimePoint(time_t(1))));
-  EXPECT_EQ(time_t(47), toTimeT(toTimePoint(time_t(47))));
-
-  TimePoint<> TP;
-  EXPECT_EQ(TP, toTimePoint(toTimeT(TP)));
-  TP += seconds(1);
-  EXPECT_EQ(TP, toTimePoint(toTimeT(TP)));
-  TP += hours(47);
-  EXPECT_EQ(TP, toTimePoint(toTimeT(TP)));
-}
-
-TEST(Chrono, StringConversion) {
-  std::string S;
-  raw_string_ostream OS(S);
-  OS << system_clock::now();
-
-  // Do a basic sanity check on the output.
-  // The format we expect is YYYY-MM-DD HH:MM:SS.MMMUUUNNN
-  StringRef Date, Time;
-  std::tie(Date, Time) = StringRef(OS.str()).split(' ');
-
-  SmallVector<StringRef, 3> Components;
-  Date.split(Components, '-');
-  ASSERT_EQ(3u, Components.size());
-  EXPECT_EQ(4u, Components[0].size());
-  EXPECT_EQ(2u, Components[1].size());
-  EXPECT_EQ(2u, Components[2].size());
-
-  StringRef Sec, Nano;
-  std::tie(Sec, Nano) = Time.split('.');
-
-  Components.clear();
-  Sec.split(Components, ':');
-  ASSERT_EQ(3u, Components.size());
-  EXPECT_EQ(2u, Components[0].size());
-  EXPECT_EQ(2u, Components[1].size());
-  EXPECT_EQ(2u, Components[2].size());
-  EXPECT_EQ(9u, Nano.size());
-}
-
-// Test that toTimePoint and toTimeT can be called with a arguments with varying
-// precisions.
-TEST(Chrono, ImplicitConversions) {
-  std::time_t TimeT = 47;
-  TimePoint<seconds> Sec = toTimePoint(TimeT);
-  TimePoint<milliseconds> Milli = toTimePoint(TimeT);
-  TimePoint<microseconds> Micro = toTimePoint(TimeT);
-  TimePoint<nanoseconds> Nano = toTimePoint(TimeT);
-  EXPECT_EQ(Sec, Milli);
-  EXPECT_EQ(Sec, Micro);
-  EXPECT_EQ(Sec, Nano);
-  EXPECT_EQ(TimeT, toTimeT(Sec));
-  EXPECT_EQ(TimeT, toTimeT(Milli));
-  EXPECT_EQ(TimeT, toTimeT(Micro));
-  EXPECT_EQ(TimeT, toTimeT(Nano));
-}
-
-} // anonymous namespace

unittests/Support/TimeValueTest.cpp

@@ -37,14 +37,4 @@ TEST(TimeValue, Win32FILETIME) {
   EXPECT_EQ(ft1970, epoch.toWin32Time());
 }
 
-TEST(TimeValue, Chrono) {
-  sys::TimeValue TV;
-  TV.fromEpochTime(0);
-  sys::TimePoint<> TP = TV;
-  EXPECT_EQ(0u, sys::toTimeT(TP));
-
-  TP += std::chrono::seconds(47);
-  TV = TP;
-  EXPECT_EQ(47u, TV.toEpochTime());
-}
 }