index 9f17baea5d6ecec7f84b699c597d8065aca75d1c..53f572f384b70a2e99b1d18c0007ab3c1385773a 100644 (file)
@@ -2574,11 +2574,8 @@ SampleHeapTupleVisible(TableScanDesc scan, Buffer buffer,
if (scan->rs_flags & SO_ALLOW_PAGEMODE)
{
- uint32 start,
- end;
-
- if (hscan->rs_ntuples == 0)
- return false;
+ uint32 start = 0,
+ end = hscan->rs_ntuples;
/*
* In pageatatime mode, heap_prepare_pagescan() already did visibility
@@ -2589,18 +2586,15 @@ SampleHeapTupleVisible(TableScanDesc scan, Buffer buffer,
* in increasing order, but it's not clear that there would be enough
* gain to justify the restriction.
*/
- start = 0;
- end = hscan->rs_ntuples - 1;
-
- while (start <= end)
+ while (start < end)
{
- uint32 mid = (start + end) / 2;
+ uint32 mid = start + (end - start) / 2;
OffsetNumber curoffset = hscan->rs_vistuples[mid];
if (tupoffset == curoffset)
return true;
else if (tupoffset < curoffset)
- end = mid - 1;
+ end = mid;
else
start = mid + 1;
}