Use ts_extract_expr_args for HypertableRestrictInfo

Refactor HypertableRestrictInfo code to make use of the newly added
ts_extract_expr_args function.

Author: svenklemm

src/hypertable_restrict_info.c

@@ -12,6 +12,7 @@
 #include <utils/builtins.h>
 #include <utils/lsyscache.h>
 #include <utils/typcache.h>
+#include <tcop/tcopprot.h>
 
 #include "hypertable_restrict_info.h"
 
@@ -20,15 +21,13 @@
 #include "dimension.h"
 #include "dimension_slice.h"
 #include "dimension_vector.h"
+#include "expression_utils.h"
 #include "guc.h"
 #include "hypercube.h"
 #include "partitioning.h"
 #include "scan_iterator.h"
 #include "utils.h"
 
-#include <inttypes.h>
-#include <tcop/tcopprot.h>
-
 typedef struct DimensionRestrictInfo
 {
 	const Dimension *dimension;
@@ -307,13 +306,12 @@ hypertable_restrict_info_get(HypertableRestrictInfo *hri, AttrNumber attno)
 
 typedef DimensionValues *(*get_dimension_values)(Const *c, bool use_or);
 
-static bool
-hypertable_restrict_info_add_expr(HypertableRestrictInfo *hri, PlannerInfo *root, List *expr_args,
-								  Oid op_oid, get_dimension_values func_get_dim_values, bool use_or)
+static void
+hypertable_restrict_info_add_expr(HypertableRestrictInfo *hri, PlannerInfo *root, Var *v,
+								  Expr *expr, Oid op_oid, get_dimension_values func_get_dim_values,
+								  bool use_or)
 {
-	Expr *leftop, *rightop, *expr;
 	DimensionRestrictInfo *dri;
-	Var *v;
 	Const *c;
 	RangeTblEntry *rte;
 	Oid columntype;
@@ -322,58 +320,36 @@ hypertable_restrict_info_add_expr(HypertableRestrictInfo *hri, PlannerInfo *root
 	Oid lefttype, righttype;
 	DimensionValues *dimvalues;
 
-	if (list_length(expr_args) != 2)
-		return false;
-
-	leftop = linitial(expr_args);
-	rightop = lsecond(expr_args);
-
-	if (IsA(leftop, RelabelType))
-		leftop = ((RelabelType *) leftop)->arg;
-	if (IsA(rightop, RelabelType))
-		rightop = ((RelabelType *) rightop)->arg;
-
-	if (IsA(leftop, Var))
-	{
-		v = (Var *) leftop;
-		expr = rightop;
-	}
-	else if (IsA(rightop, Var))
-	{
-		v = (Var *) rightop;
-		expr = leftop;
-		op_oid = get_commutator(op_oid);
-	}
-	else
-		return false;
-
 	dri = hypertable_restrict_info_get(hri, v->varattno);
 	/* the attribute is not a dimension */
 	if (dri == NULL)
-		return false;
+		return;
 
 	expr = (Expr *) eval_const_expressions(root, (Node *) expr);
 
 	if (!IsA(expr, Const) || !OidIsValid(op_oid) || !op_strict(op_oid))
-		return false;
+		return;
 
 	c = (Const *) expr;
 
 	/* quick check for a NULL constant */
 	if (c->constisnull)
-		return false;
+		return;
 
 	rte = rt_fetch(v->varno, root->parse->rtable);
 
 	columntype = get_atttype(rte->relid, dri->dimension->column_attno);
 	tce = lookup_type_cache(columntype, TYPECACHE_BTREE_OPFAMILY);
 
 	if (!op_in_opfamily(op_oid, tce->btree_opf))
-		return false;
+		return;
 
 	get_op_opfamily_properties(op_oid, tce->btree_opf, false, &strategy, &lefttype, &righttype);
 	dimvalues = func_get_dim_values(c, use_or);
-	return dimension_restrict_info_add(dri, strategy, c->constcollid, dimvalues);
+	if (dimension_restrict_info_add(dri, strategy, c->constcollid, dimvalues))
+	{
+		hri->num_base_restrictions++;
+	}
 }
 
 static DimensionValues *
@@ -426,48 +402,41 @@ static void
 hypertable_restrict_info_add_restrict_info(HypertableRestrictInfo *hri, PlannerInfo *root,
 										   RestrictInfo *ri)
 {
-	bool added = false;
+	Oid opno;
+	Var *var;
+	Expr *arg_value;
 
 	Expr *e = ri->clause;
 
 	/* Same as constraint_exclusion */
 	if (contain_mutable_functions((Node *) e))
 		return;
 
-	switch (nodeTag(e))
+	if (ts_extract_expr_args(e, &var, &arg_value, &opno, NULL))
 	{
-		case T_OpExpr:
-		{
-			OpExpr *op_expr = (OpExpr *) e;
-
-			added = hypertable_restrict_info_add_expr(hri,
-													  root,
-													  op_expr->args,
-													  op_expr->opno,
-													  dimension_values_create_from_single_element,
-													  false);
-			break;
-		}
+		get_dimension_values value_func;
+		bool use_or;
 
-		case T_ScalarArrayOpExpr:
+		switch (nodeTag(e))
 		{
-			ScalarArrayOpExpr *scalar_expr = (ScalarArrayOpExpr *) e;
-
-			added = hypertable_restrict_info_add_expr(hri,
-													  root,
-													  scalar_expr->args,
-													  scalar_expr->opno,
-													  dimension_values_create_from_array,
-													  scalar_expr->useOr);
-			break;
+			case T_OpExpr:
+			{
+				value_func = dimension_values_create_from_single_element;
+				use_or = false;
+				break;
+			}
+			case T_ScalarArrayOpExpr:
+			{
+				value_func = dimension_values_create_from_array;
+				use_or = castNode(ScalarArrayOpExpr, e)->useOr;
+				break;
+			}
+			default:
+				/* we don't support other node types */
+				return;
 		}
-		default:
-			/* we don't support other node types */
-			break;
+		hypertable_restrict_info_add_expr(hri, root, var, arg_value, opno, value_func, use_or);
 	}
-
-	if (added)
-		hri->num_base_restrictions++;
 }
 
 void