Function MultiExecBitmapOr

src/backend/executor/nodeBitmapOr.c:119–207

---------------------------------------------------------------- * MultiExecBitmapOr * * BitmapOr node gets the bitmaps generated from BitmapIndexScan * nodes and outputs a bitmap that ORs all input bitmaps. * * The first input bitmap is utilized to store the result of the * OR and returned to the caller. In addition, the output points * to a newly created OpStream node o

 * ----------------------------------------------------------------
 */
Node *
MultiExecBitmapOr(BitmapOrState *node)
{
	PlanState **bitmapplans;
	int			nplans;
	int			i;
	/*
	 * Cloudberry uses result for TIDBitmap result, and node->bitmap for
	 * StreamBitmap result if there is any StreamBitmap.
	 *
	 * At last it will union them and return.
	 */
	TIDBitmap  *result = NULL;

	/* must provide our own instrumentation support */
	if (node->ps.instrument)
		InstrStartNode(node->ps.instrument);

	/*
	 * get information from the node
	 */
	bitmapplans = node->bitmapplans;
	nplans = node->nplans;

	/*
	 * Scan all the subplans and OR their result bitmaps
	 */
	for (i = 0; i < nplans; i++)
	{
		PlanState  *subnode = bitmapplans[i];
		Node	   *subresult = NULL;

		/*
		 * Note for further merge iteration:
		 *     Cloudberry's BitmapIndexScan returns a StreamBitmap
		 */
		subresult = MultiExecProcNode(subnode);

		if (subresult == NULL)
			continue;

		if (!(IsA(subresult, TIDBitmap) ||
			  IsA(subresult, StreamBitmap)))
			elog(ERROR, "unrecognized result from subplan");

		if (IsA(subresult, TIDBitmap))
		{
			/* if it's a TIDBitmap, union into result */
			if (result == NULL)
				result = (TIDBitmap *)subresult;
			else
			{
				tbm_union(result, (TIDBitmap *)subresult);
				tbm_generic_free(subresult);
			}
		}
		else
		{