[llvm] [SystemZ][z/OS] Add UtcClock extension to chrono.h/.cpp (PR #67846)

[Yusra Syeda via llvm-commits]

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@@ -50,44 +68,63 @@ raw_ostream &operator<<(raw_ostream &OS, TimePoint<> TP) {
                                .count()));
 }
 
-void format_provider<TimePoint<>>::format(const TimePoint<> &T, raw_ostream &OS,
-                                          StringRef Style) {
+template <class T>
+static void format(const T &Fractional, struct tm &LT, raw_ostream &OS,
+                   StringRef Style) {
   using namespace std::chrono;
-  TimePoint<seconds> Truncated = time_point_cast<seconds>(T);
-  auto Fractional = T - Truncated;
-  struct tm LT = getStructTM(Truncated);
   // Handle extensions first. strftime mangles unknown %x on some platforms.
-  if (Style.empty()) Style = "%Y-%m-%d %H:%M:%S.%N";
+  if (Style.empty())
+    Style = "%Y-%m-%d %H:%M:%S.%N";
   std::string Format;
   raw_string_ostream FStream(Format);
   for (unsigned I = 0; I < Style.size(); ++I) {
-    if (Style[I] == '%' && Style.size() > I + 1) switch (Style[I + 1]) {
-        case 'L':  // Milliseconds, from Ruby.
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ysyeda wrote:

Thanks, the unrelated formatting is removed now.

https://github.com/llvm/llvm-project/pull/67846