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Fix end-of-loop optimization in pglz_find_match() function.

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After the recent pglz optimization patch, the next/prev pointers in the
hash table are never NULL, INVALID_ENTRY_PTR is used to represent invalid
entries instead. The end-of-loop check in pglz_find_match() function didn't
get the memo. The result was the same from a correctness point of view, but
because the NULL-check would never fail, the tiny optimization turned into
a pessimization.

Reported by Stephen Frost, using Coverity scanner.
This commit is contained in:
Heikki Linnakangas 2013-07-17 20:24:28 +03:00
parent 750f43685b
commit 3f2adace1e
1 changed files with 1 additions and 1 deletions
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2
src/backend/utils/adt/pg_lzcompress.c
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@ -466,7 +466,7 @@ pglz_find_match(int16 *hstart, const char *input, const char *end,
* Be happy with lesser good matches the more entries we visited. But * Be happy with lesser good matches the more entries we visited. But
* no point in doing calculation if we're at end of list. * no point in doing calculation if we're at end of list.
*/ */
if (hent) if (hent != INVALID_ENTRY_PTR)
{ {
if (len >= good_match) if (len >= good_match)
break; break;