Fix obsolete comments in varstr_cmp().

Author: jeff-davis

src/backend/utils/adt/varlena.c

@@ -1521,12 +1521,12 @@ check_collation_set(Oid collid)
 	}
 }
 
-/* varstr_cmp()
- * Comparison function for text strings with given lengths.
- * Includes locale support, but must copy strings to temporary memory
- *	to allow null-termination for inputs to strcoll().
- * Returns an integer less than, equal to, or greater than zero, indicating
- * whether arg1 is less than, equal to, or greater than arg2.
+/*
+ * varstr_cmp()
+ *
+ * Comparison function for text strings with given lengths, using the
+ * appropriate locale. Returns an integer less than, equal to, or greater than
+ * zero, indicating whether arg1 is less than, equal to, or greater than arg2.
  *
  * Note: many functions that depend on this are marked leakproof; therefore,
  * avoid reporting the actual contents of the input when throwing errors.
@@ -1541,12 +1541,6 @@ varstr_cmp(const char *arg1, int len1, const char *arg2, int len2, Oid collid)
 
 	check_collation_set(collid);
 
-	/*
-	 * Unfortunately, there is no strncoll(), so in the non-C locale case we
-	 * have to do some memory copying.  This turns out to be significantly
-	 * slower, so we optimize the case where LC_COLLATE is C.  We also try to
-	 * optimize relatively-short strings by avoiding palloc/pfree overhead.
-	 */
 	if (lc_collate_is_c(collid))
 	{
 		result = memcmp(arg1, arg2, Min(len1, len2));