feat: Support multiple input sources for CometNativeExec (#87)

CometNativeExec currently limits the number of input source. That blocks the operators with multiple input sources like join operator. This patch generalizes the input source handling to remove the limitation.

spark/src/main/scala/org/apache/comet/CometSparkSessionExtensions.scala

@@ -237,7 +237,7 @@ class CometSparkSessionExtensions
           val newOp = transform1(op)
           newOp match {
             case Some(nativeOp) =>
-              CometProjectExec(nativeOp, op, op.projectList, op.output, op.child)
+              CometProjectExec(nativeOp, op, op.projectList, op.output, op.child, None)
             case None =>
               op
           }
@@ -246,7 +246,7 @@ class CometSparkSessionExtensions
           val newOp = transform1(op)
           newOp match {
             case Some(nativeOp) =>
-              CometFilterExec(nativeOp, op, op.condition, op.child)
+              CometFilterExec(nativeOp, op, op.condition, op.child, None)
             case None =>
               op
           }
@@ -255,7 +255,7 @@ class CometSparkSessionExtensions
           val newOp = transform1(op)
           newOp match {
             case Some(nativeOp) =>
-              CometSortExec(nativeOp, op, op.sortOrder, op.child)
+              CometSortExec(nativeOp, op, op.sortOrder, op.child, None)
             case None =>
               op
           }
@@ -264,7 +264,7 @@ class CometSparkSessionExtensions
           val newOp = transform1(op)
           newOp match {
             case Some(nativeOp) =>
-              CometLocalLimitExec(nativeOp, op, op.limit, op.child)
+              CometLocalLimitExec(nativeOp, op, op.limit, op.child, None)
             case None =>
               op
           }
@@ -273,7 +273,7 @@ class CometSparkSessionExtensions
           val newOp = transform1(op)
           newOp match {
             case Some(nativeOp) =>
-              CometGlobalLimitExec(nativeOp, op, op.limit, op.child)
+              CometGlobalLimitExec(nativeOp, op, op.limit, op.child, None)
             case None =>
               op
           }
@@ -282,7 +282,7 @@ class CometSparkSessionExtensions
           val newOp = transform1(op)
           newOp match {
             case Some(nativeOp) =>
-              CometExpandExec(nativeOp, op, op.projections, op.child)
+              CometExpandExec(nativeOp, op, op.projections, op.child, None)
             case None =>
               op
           }
@@ -304,7 +304,8 @@ class CometSparkSessionExtensions
                 aggExprs,
                 child.output,
                 if (modes.nonEmpty) Some(modes.head) else None,
-                child)
+                child,
+                None)
             case None =>
               op
           }
@@ -425,10 +426,11 @@ class CometSparkSessionExtensions
         newPlan.transformDown {
           case op: CometNativeExec =>
             if (firstNativeOp) {
-              op.convertBlock()
               firstNativeOp = false
+              op.convertBlock()
+            } else {
+              op
             }
-            op
           case op =>
             firstNativeOp = true
             op

spark/src/main/scala/org/apache/comet/serde/QueryPlanSerde.scala

@@ -1718,7 +1718,7 @@ object QueryPlanSerde extends Logging with ShimQueryPlanSerde {
                 case op if !op.isInstanceOf[CometPlan] =>
                   seenNonNativeOp = true
                   op
-                case op @ CometHashAggregateExec(_, _, _, _, input, Some(Partial), _) =>
+                case op @ CometHashAggregateExec(_, _, _, _, input, Some(Partial), _, _) =>
                   if (!seenNonNativeOp && partialAggInput.isEmpty) {
                     partialAggInput = Some(input)
                   }

spark/src/main/scala/org/apache/spark/sql/comet/ZippedPartitionsRDD.scala

@@ -0,0 +1,62 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.apache.spark.sql.comet
+
+import org.apache.spark.{Partition, SparkContext, TaskContext}
+import org.apache.spark.rdd.{RDD, RDDOperationScope, ZippedPartitionsBaseRDD, ZippedPartitionsPartition}
+import org.apache.spark.sql.vectorized.ColumnarBatch
+
+/**
+ * Similar to Spark `ZippedPartitionsRDD[1-4]` classes, this class is used to zip partitions of
+ * the multiple RDDs into a single RDD. Spark `ZippedPartitionsRDD[1-4]` classes only support at
+ * most 4 RDDs. This class is used to support more than 4 RDDs. This ZipPartitionsRDD is used to
+ * zip the input sources of the Comet physical plan. So it only zips partitions of ColumnarBatch.
+ */
+private[spark] class ZippedPartitionsRDD(
+    sc: SparkContext,
+    var f: (Seq[Iterator[ColumnarBatch]]) => Iterator[ColumnarBatch],
+    var zipRdds: Seq[RDD[ColumnarBatch]],
+    preservesPartitioning: Boolean = false)
+    extends ZippedPartitionsBaseRDD[ColumnarBatch](sc, zipRdds, preservesPartitioning) {
+
+  override def compute(s: Partition, context: TaskContext): Iterator[ColumnarBatch] = {
+    val partitions = s.asInstanceOf[ZippedPartitionsPartition].partitions
+    val iterators =
+      zipRdds.zipWithIndex.map(pair => pair._1.iterator(partitions(pair._2), context))
+    f(iterators)
+  }
+
+  override def clearDependencies(): Unit = {
+    super.clearDependencies()
+    zipRdds = null
+    f = null
+  }
+}
+
+object ZippedPartitionsRDD {
+  def apply(sc: SparkContext, rdds: Seq[RDD[ColumnarBatch]])(
+      f: (Seq[Iterator[ColumnarBatch]]) => Iterator[ColumnarBatch]): RDD[ColumnarBatch] =
+    withScope(sc) {
+      new ZippedPartitionsRDD(sc, f, rdds)
+    }
+
+  private[spark] def withScope[U](sc: SparkContext)(body: => U): U =
+    RDDOperationScope.withScope[U](sc)(body)
+}