Add check for signed integer overflow in diffTimestamp (facebookincub…

…ator#10675)

Summary:
Pull Request resolved: facebookincubator#10675

Handle unsinged integer overflow error and rethrow with more informative error message.

Reviewed By: kevinwilfong

Differential Revision: D60876240

fbshipit-source-id: 5d096db6162fb91873c798396afde109e26e7a61

velox/functions/prestosql/DateTimeImpl.h

@@ -282,10 +282,25 @@ FOLLY_ALWAYS_INLINE int64_t diffTimestamp(
       std::chrono::duration_cast<std::chrono::milliseconds>(
           fromTimepoint - fromDaysTimepoint)
           .count();
-  const uint64_t toTimeInstantOfDay =
-      std::chrono::duration_cast<std::chrono::milliseconds>(
-          toTimepoint - toDaysTimepoint)
-          .count();
+
+  uint64_t toTimeInstantOfDay = 0;
+  uint64_t toTimePointMillis = toTimepoint.time_since_epoch().count();
+  uint64_t toDaysTimepointMillis =
+      std::chrono::
+          time_point<std::chrono::system_clock, std::chrono::milliseconds>(
+              toDaysTimepoint)
+              .time_since_epoch()
+              .count();
+  bool overflow = __builtin_sub_overflow(
+      toTimePointMillis, toDaysTimepointMillis, &toTimeInstantOfDay);
+  VELOX_USER_CHECK_EQ(
+      overflow,
+      false,
+      "{} - {} Causes arithmetic overflow: {} - {}",
+      fromTimestamp.toString(),
+      toTimestamp.toString(),
+      toTimePointMillis,
+      toDaysTimepointMillis)
   const uint8_t fromDay = static_cast<unsigned>(fromCalDate.day()),
                 fromMonth = static_cast<unsigned>(fromCalDate.month());
   const uint8_t toDay = static_cast<unsigned>(toCalDate.day()),

velox/functions/prestosql/tests/DateTimeFunctionsTest.cpp

@@ -2558,6 +2558,23 @@ TEST_F(DateTimeFunctionsTest, dateDiffTimestamp) {
       dateDiff("invalid_unit", Timestamp(1, 0), Timestamp(0, 0)),
       "Unsupported datetime unit: invalid_unit");
 
+  // Check for integer overflow when result unit is month or larger.
+  EXPECT_EQ(
+      -622191233,
+      dateDiff("day", Timestamp(0, 0), Timestamp(9223372036854775, 0)));
+  EXPECT_EQ(
+      -88884461,
+      dateDiff("week", Timestamp(0, 0), Timestamp(9223372036854775, 0)));
+  VELOX_ASSERT_THROW(
+      dateDiff("month", Timestamp(0, 0), Timestamp(9223372036854775, 0)),
+      "Causes arithmetic overflow:");
+  VELOX_ASSERT_THROW(
+      dateDiff("quarter", Timestamp(0, 0), Timestamp(9223372036854775, 0)),
+      "Causes arithmetic overflow:");
+  VELOX_ASSERT_THROW(
+      dateDiff("year", Timestamp(0, 0), Timestamp(9223372036854775, 0)),
+      "Causes arithmetic overflow:");
+
   // Simple tests
   EXPECT_EQ(
       60 * 1000 + 500,