From 2613b7478573c7fc833c90ff8aa731a15d32aaaf Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Thu, 25 Aug 2005 05:01:43 +0000
Subject: [PATCH] Factor out the common subexpression month_remainder *
DAYS_PER_MONTH in interval_mul and interval_div. This avoids an optimization
bug in A Certain Company's compiler (and given their explanation, I wouldn't
be surprised if other compilers blow it too). Besides the code seems more
clear this way --- in the original formulation, you had to mentally recognize
the common subexpression in order to understand what was going on.
---
src/backend/utils/adt/timestamp.c | 24 +++++++++++-------------
1 file changed, 11 insertions(+), 13 deletions(-)
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index c218422a79..2b15e64e06 100644
--- a/src/backend/utils/adt/timestamp.c
+++ b/src/backend/utils/adt/timestamp.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/utils/adt/timestamp.c,v 1.150 2005/08/25 03:53:22 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/adt/timestamp.c,v 1.151 2005/08/25 05:01:43 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -2262,7 +2262,7 @@ interval_mul(PG_FUNCTION_ARGS)
{
Interval *span = PG_GETARG_INTERVAL_P(0);
float8 factor = PG_GETARG_FLOAT8(1);
- double month_remainder, day_remainder;
+ double month_remainder, day_remainder, month_remainder_days;
Interval *result;
result = (Interval *) palloc(sizeof(Interval));
@@ -2276,17 +2276,15 @@ interval_mul(PG_FUNCTION_ARGS)
/* Cascade fractions to lower units */
/* fractional months full days into days */
- result->day += month_remainder * DAYS_PER_MONTH;
+ month_remainder_days = month_remainder * DAYS_PER_MONTH;
+ result->day += month_remainder_days;
/* fractional months partial days into time */
- day_remainder += (month_remainder * DAYS_PER_MONTH) -
- (int)(month_remainder * DAYS_PER_MONTH);
+ day_remainder += month_remainder_days - (int) month_remainder_days;
#ifdef HAVE_INT64_TIMESTAMP
- result->time = rint(span->time * factor +
- day_remainder * USECS_PER_DAY);
+ result->time = rint(span->time * factor + day_remainder * USECS_PER_DAY);
#else
- result->time = JROUND(span->time * factor +
- day_remainder * SECS_PER_DAY);
+ result->time = JROUND(span->time * factor + day_remainder * SECS_PER_DAY);
#endif
result = DatumGetIntervalP(DirectFunctionCall1(interval_justify_hours,
@@ -2309,7 +2307,7 @@ interval_div(PG_FUNCTION_ARGS)
{
Interval *span = PG_GETARG_INTERVAL_P(0);
float8 factor = PG_GETARG_FLOAT8(1);
- double month_remainder, day_remainder;
+ double month_remainder, day_remainder, month_remainder_days;
Interval *result;
result = (Interval *) palloc(sizeof(Interval));
@@ -2329,10 +2327,10 @@ interval_div(PG_FUNCTION_ARGS)
/* Cascade fractions to lower units */
/* fractional months full days into days */
- result->day += month_remainder * DAYS_PER_MONTH;
+ month_remainder_days = month_remainder * DAYS_PER_MONTH;
+ result->day += month_remainder_days;
/* fractional months partial days into time */
- day_remainder += (month_remainder * DAYS_PER_MONTH) -
- (int)(month_remainder * DAYS_PER_MONTH);
+ day_remainder += month_remainder_days - (int) month_remainder_days;
#ifdef HAVE_INT64_TIMESTAMP
result->time += rint(day_remainder * USECS_PER_DAY);