Phase 2 of read-only-plans project: restructure expression-tree nodes

so that all executable expression nodes inherit from a common supertype
Expr.  This is somewhat of an exercise in code purity rather than any
real functional advance, but getting rid of the extra Oper or Func node
formerly used in each operator or function call should provide at least
a little space and speed improvement.
initdb forced by changes in stored-rules representation.

1 files changed, 20 insertions, 33 deletions

diff --git a/src/backend/optimizer/path/tidpath.c b/src/backend/optimizer/path/tidpath.c
index 27fe9e281f3..f11ff81ea41 100644
--- a/src/backend/optimizer/path/tidpath.c
+++ b/src/backend/optimizer/path/tidpath.c
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/optimizer/path/tidpath.c,v 1.12 2002/11/24 21:52:14 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/optimizer/path/tidpath.c,v 1.13 2002/12/12 15:49:32 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -27,15 +27,14 @@
 
 static List *TidqualFromRestrictinfo(List *relids, List *restrictinfo);
 static bool isEvaluable(int varno, Node *node);
-static Node *TidequalClause(int varno, Expr *node);
+static Node *TidequalClause(int varno, OpExpr *node);
 static List *TidqualFromExpr(int varno, Expr *expr);
 
-static
-bool
+static bool
 isEvaluable(int varno, Node *node)
 {
 	List	   *lst;
-	Expr	   *expr;
+	FuncExpr   *expr;
 
 	if (IsA(node, Const))
 		return true;
@@ -51,7 +50,7 @@ isEvaluable(int varno, Node *node)
 	}
 	if (!is_funcclause(node))
 		return false;
-	expr = (Expr *) node;
+	expr = (FuncExpr *) node;
 	foreach(lst, expr->args)
 	{
 		if (!isEvaluable(varno, lfirst(lst)))
@@ -66,33 +65,26 @@ isEvaluable(int varno, Node *node)
  *	Extract the right node if the opclause is CTID= ....
  *	  or	the left  node if the opclause is ....=CTID
  */
-static
-Node *
-TidequalClause(int varno, Expr *node)
+static Node *
+TidequalClause(int varno, OpExpr *node)
 {
-	Node	   *rnode = 0,
+	Node	   *rnode = NULL,
 			   *arg1,
 			   *arg2,
 			   *arg;
-	Oper	   *oper;
 	Var		   *var;
 	Const	   *aconst;
 	Param	   *param;
-	Expr	   *expr;
+	FuncExpr   *expr;
 
-	if (!node->oper)
-		return rnode;
-	if (!node->args)
+	if (node->opno != TIDEqualOperator)
 		return rnode;
 	if (length(node->args) != 2)
 		return rnode;
-	oper = (Oper *) node->oper;
-	if (oper->opno != TIDEqualOperator)
-		return rnode;
 	arg1 = lfirst(node->args);
 	arg2 = lsecond(node->args);
 
-	arg = (Node *) 0;
+	arg = NULL;
 	if (IsA(arg1, Var))
 	{
 		var = (Var *) arg1;
@@ -138,11 +130,9 @@ TidequalClause(int varno, Expr *node)
 				return rnode;
 			rnode = arg;
 			break;
-		case T_Expr:
-			expr = (Expr *) arg;
-			if (expr->typeOid != TIDOID)
-				return rnode;
-			if (expr->opType != FUNC_EXPR)
+		case T_FuncExpr:
+			expr = (FuncExpr *) arg;
+			if (expr->funcresulttype != TIDOID)
 				return rnode;
 			if (isEvaluable(varno, (Node *) expr))
 				rnode = arg;
@@ -162,8 +152,7 @@ TidequalClause(int varno, Expr *node)
  *	CTID values if we could extract the CTID values from a member
  *	node.
  */
-static
-List *
+static List *
 TidqualFromExpr(int varno, Expr *expr)
 {
 	List	   *rlst = NIL,
@@ -174,17 +163,15 @@ TidqualFromExpr(int varno, Expr *expr)
 
 	if (is_opclause(node))
 	{
-		rnode = TidequalClause(varno, expr);
+		rnode = TidequalClause(varno, (OpExpr *) expr);
 		if (rnode)
 			rlst = lcons(rnode, rlst);
 	}
 	else if (and_clause(node))
 	{
-		foreach(lst, expr->args)
+		foreach(lst, ((BoolExpr *) expr)->args)
 		{
 			node = lfirst(lst);
-			if (!IsA(node, Expr))
-				continue;
 			rlst = TidqualFromExpr(varno, (Expr *) node);
 			if (rlst)
 				break;
@@ -192,11 +179,11 @@ TidqualFromExpr(int varno, Expr *expr)
 	}
 	else if (or_clause(node))
 	{
-		foreach(lst, expr->args)
+		foreach(lst, ((BoolExpr *) expr)->args)
 		{
 			node = lfirst(lst);
-			if (IsA(node, Expr) &&
-				(frtn = TidqualFromExpr(varno, (Expr *) node)))
+			frtn = TidqualFromExpr(varno, (Expr *) node);
+			if (frtn)
 				rlst = nconc(rlst, frtn);
 			else
 			{