diff options
| author | Tom Lane <tgl@sss.pgh.pa.us> | 2021-09-26 14:24:03 -0400 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2021-09-26 14:24:03 -0400 |
| commit | e94c1a55dada49772622d2be2d17a2a9973b2661 (patch) | |
| tree | 848acb7ba233c031c47057e7c61f3c700fd032f9 | |
| parent | 7c1d8a243f8bd46604c9b292f392aab170eed821 (diff) | |
| download | postgresql-e94c1a55dada49772622d2be2d17a2a9973b2661.tar.gz postgresql-e94c1a55dada49772622d2be2d17a2a9973b2661.zip | |
Avoid unnecessary division in interval_cmp_value().
Splitting the time field into days and microseconds is pretty
useless when we're just going to recombine those values.
It's unclear if anyone will notice the speedup in real-world
cases, but a cycle shaved is a cycle earned.
Discussion: https://postgr.es/m/2629129.1632675713@sss.pgh.pa.us
| -rw-r--r-- | src/backend/utils/adt/timestamp.c | 13 |
1 files changed, 5 insertions, 8 deletions
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c index 1c0bf0aa5c8..cb9faff0bbc 100644 --- a/src/backend/utils/adt/timestamp.c +++ b/src/backend/utils/adt/timestamp.c @@ -2352,20 +2352,17 @@ static inline INT128 interval_cmp_value(const Interval *interval) { INT128 span; - int64 dayfraction; int64 days; /* - * Separate time field into days and dayfraction, then add the month and - * day fields to the days part. We cannot overflow int64 days here. + * Combine the month and day fields into an integral number of days. + * Because the inputs are int32, int64 arithmetic suffices here. */ - dayfraction = interval->time % USECS_PER_DAY; - days = interval->time / USECS_PER_DAY; - days += interval->month * INT64CONST(30); + days = interval->month * INT64CONST(30); days += interval->day; - /* Widen dayfraction to 128 bits */ - span = int64_to_int128(dayfraction); + /* Widen time field to 128 bits */ + span = int64_to_int128(interval->time); /* Scale up days to microseconds, forming a 128-bit product */ int128_add_int64_mul_int64(&span, days, USECS_PER_DAY); |