1 files changed, 209 insertions, 0 deletions
diff --git a/src/backend/executor/nodeBitmapOr.c b/src/backend/executor/nodeBitmapOr.c
new file mode 100644
index 00000000000..f4ef17223c8
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+++ b/src/backend/executor/nodeBitmapOr.c
@@ -0,0 +1,209 @@
+/*-------------------------------------------------------------------------
+ *
+ * nodeBitmapOr.c
+ *	  routines to handle BitmapOr nodes.
+ *
+ * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ *	  $PostgreSQL: pgsql/src/backend/executor/nodeBitmapOr.c,v 1.1 2005/04/19 22:35:12 tgl Exp $
+ *
+ *-------------------------------------------------------------------------
+ */
+/* INTERFACE ROUTINES
+ *		ExecInitBitmapOr	- initialize the BitmapOr node
+ *		MultiExecBitmapOr	- retrieve the result bitmap from the node
+ *		ExecEndBitmapOr		- shut down the BitmapOr node
+ *		ExecReScanBitmapOr	- rescan the BitmapOr node
+ *
+ *	 NOTES
+ *		BitmapOr nodes don't make use of their left and right
+ *		subtrees, rather they maintain a list of subplans,
+ *		much like Append nodes.  The logic is much simpler than
+ *		Append, however, since we needn't cope with forward/backward
+ *		execution.
+ */
+
+#include "postgres.h"
+
+#include "executor/execdebug.h"
+#include "executor/instrument.h"
+#include "executor/nodeBitmapOr.h"
+
+
+/* ----------------------------------------------------------------
+ *		ExecInitBitmapOr
+ *
+ *		Begin all of the subscans of the BitmapOr node.
+ * ----------------------------------------------------------------
+ */
+BitmapOrState *
+ExecInitBitmapOr(BitmapOr *node, EState *estate)
+{
+	BitmapOrState *bitmaporstate = makeNode(BitmapOrState);
+	PlanState **bitmapplanstates;
+	int			nplans;
+	int			i;
+	Plan	   *initNode;
+
+	CXT1_printf("ExecInitBitmapOr: context is %d\n", CurrentMemoryContext);
+
+	/*
+	 * Set up empty vector of subplan states
+	 */
+	nplans = list_length(node->bitmapplans);
+
+	bitmapplanstates = (PlanState **) palloc0(nplans * sizeof(PlanState *));
+
+	/*
+	 * create new BitmapOrState for our BitmapOr node
+	 */
+	bitmaporstate->ps.plan = (Plan *) node;
+	bitmaporstate->ps.state = estate;
+	bitmaporstate->bitmapplans = bitmapplanstates;
+	bitmaporstate->nplans = nplans;
+
+	/*
+	 * Miscellaneous initialization
+	 *
+	 * BitmapOr plans don't have expression contexts because they never call
+	 * ExecQual or ExecProject.  They don't need any tuple slots either.
+	 */
+
+#define BITMAPOR_NSLOTS 0
+
+	/*
+	 * call ExecInitNode on each of the plans to be executed and save the
+	 * results into the array "bitmapplanstates".
+	 */
+	for (i = 0; i < nplans; i++)
+	{
+		initNode = (Plan *) list_nth(node->bitmapplans, i);
+		bitmapplanstates[i] = ExecInitNode(initNode, estate);
+	}
+
+	return bitmaporstate;
+}
+
+int
+ExecCountSlotsBitmapOr(BitmapOr *node)
+{
+	ListCell   *plan;
+	int			nSlots = 0;
+
+	foreach(plan, node->bitmapplans)
+		nSlots += ExecCountSlotsNode((Plan *) lfirst(plan));
+	return nSlots + BITMAPOR_NSLOTS;
+}
+
+/* ----------------------------------------------------------------
+ *	   MultiExecBitmapOr
+ * ----------------------------------------------------------------
+ */
+Node *
+MultiExecBitmapOr(BitmapOrState *node)
+{
+	PlanState **bitmapplans;
+	int			nplans;
+	int			i;
+	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];
+		TIDBitmap  *subresult;
+
+		subresult = (TIDBitmap *) MultiExecProcNode(subnode);
+
+		if (!subresult || !IsA(subresult, TIDBitmap))
+			elog(ERROR, "unrecognized result from subplan");
+
+		if (result == NULL)
+			result = subresult;			/* first subplan */
+		else
+		{
+			tbm_union(result, subresult);
+			tbm_free(subresult);
+		}
+	}
+
+	/* We could return an empty result set here? */
+	if (result == NULL)
+		elog(ERROR, "BitmapOr doesn't support zero inputs");
+
+	/* must provide our own instrumentation support */
+	if (node->ps.instrument)
+		InstrStopNodeMulti(node->ps.instrument, 0 /* XXX */);
+
+	return (Node *) result;
+}
+
+/* ----------------------------------------------------------------
+ *		ExecEndBitmapOr
+ *
+ *		Shuts down the subscans of the BitmapOr node.
+ *
+ *		Returns nothing of interest.
+ * ----------------------------------------------------------------
+ */
+void
+ExecEndBitmapOr(BitmapOrState *node)
+{
+	PlanState **bitmapplans;
+	int			nplans;
+	int			i;
+
+	/*
+	 * get information from the node
+	 */
+	bitmapplans = node->bitmapplans;
+	nplans = node->nplans;
+
+	/*
+	 * shut down each of the subscans (that we've initialized)
+	 */
+	for (i = 0; i < nplans; i++)
+	{
+		if (bitmapplans[i])
+			ExecEndNode(bitmapplans[i]);
+	}
+}
+
+void
+ExecReScanBitmapOr(BitmapOrState *node, ExprContext *exprCtxt)
+{
+	int			i;
+
+	for (i = 0; i < node->nplans; i++)
+	{
+		PlanState  *subnode = node->bitmapplans[i];
+
+		/*
+		 * ExecReScan doesn't know about my subplans, so I have to do
+		 * changed-parameter signaling myself.
+		 */
+		if (node->ps.chgParam != NULL)
+			UpdateChangedParamSet(subnode, node->ps.chgParam);
+
+		/*
+		 * Always rescan the inputs immediately, to ensure we can pass down
+		 * any outer tuple that might be used in index quals.
+		 */
+		ExecReScan(subnode, exprCtxt);
+	}
+}