More efficient writing of small (less than an hour) java.time.Duration values

Author: plokhotnyuk

jsoniter-scala-core/js/src/main/scala/com/github/plokhotnyuk/jsoniter_scala/core/JsonWriter.scala

@@ -1771,8 +1771,12 @@ final class JsonWriter private[jsoniter_scala](
       val effectiveTotalSecs =
         if (totalSecs < 0) (-nano >> 31) - totalSecs
         else totalSecs
-      val hours = effectiveTotalSecs / 3600
-      val secsOfHour = (effectiveTotalSecs - hours * 3600).toInt
+      var hours = 0L
+      var secsOfHour = effectiveTotalSecs.toInt
+      if (effectiveTotalSecs >= 3600) {
+        hours = effectiveTotalSecs / 3600
+        secsOfHour = (effectiveTotalSecs - (hours << 12) + (hours << 9) - (hours << 4)).toInt // (effectiveTotalSecs - hours * 3600).toInt
+      }
       val minutes = secsOfHour * 17477 >> 20 // divide a small positive int by 60
       val seconds = secsOfHour - minutes * 60
       val ds = digits

jsoniter-scala-core/jvm/src/main/scala/com/github/plokhotnyuk/jsoniter_scala/core/JsonWriter.scala

@@ -1598,8 +1598,12 @@ final class JsonWriter private[jsoniter_scala](
       val effectiveTotalSecs =
         if (totalSecs < 0) (-nano >> 31) - totalSecs
         else totalSecs
-      val hours = Math.multiplyHigh(effectiveTotalSecs >> 4, 655884233731895169L) >> 3 // divide a positive long by 3600
-      val secsOfHour = (effectiveTotalSecs - hours * 3600).toInt
+      var hours = 0L
+      var secsOfHour = effectiveTotalSecs.toInt
+      if (effectiveTotalSecs >= 3600) {
+        hours = Math.multiplyHigh(effectiveTotalSecs >> 4, 655884233731895169L) >> 3 // divide a positive long by 3600
+        secsOfHour = (effectiveTotalSecs - hours * 3600).toInt
+      }
       val minutes = secsOfHour * 17477 >> 20 // divide a small positive int by 60
       val seconds = secsOfHour - minutes * 60
       val ds = digits

jsoniter-scala-core/native/src/main/scala/com/github/plokhotnyuk/jsoniter_scala/core/JsonWriter.scala

@@ -1598,8 +1598,12 @@ final class JsonWriter private[jsoniter_scala](
       val effectiveTotalSecs =
         if (totalSecs < 0) (-nano >> 31) - totalSecs
         else totalSecs
-      val hours = NativeMath.multiplyHigh(effectiveTotalSecs >> 4, 655884233731895169L) >> 3 // divide a positive long by 3600
-      val secsOfHour = (effectiveTotalSecs - hours * 3600).toInt
+      var hours = 0L
+      var secsOfHour = effectiveTotalSecs.toInt
+      if (effectiveTotalSecs >= 3600) {
+        hours = NativeMath.multiplyHigh(effectiveTotalSecs >> 4, 655884233731895169L) >> 3 // divide a positive long by 3600
+        secsOfHour = (effectiveTotalSecs - hours * 3600).toInt
+      }
       val minutes = secsOfHour * 17477 >> 20 // divide a small positive int by 60
       val seconds = secsOfHour - minutes * 60
       val ds = digits