Fix

sql-plugin/src/main/scala/org/apache/spark/sql/rapids/aggregate/GpuHyperLogLogPlusPlus.scala

@@ -19,11 +19,11 @@ package org.apache.spark.sql.rapids.aggregate
 import scala.collection.immutable.Seq
 
 import ai.rapids.cudf
-import ai.rapids.cudf.{ColumnVector, DType, GroupByAggregation, ReductionAggregation}
+import ai.rapids.cudf.{DType, GroupByAggregation, ReductionAggregation}
 import com.nvidia.spark.rapids._
-//import com.nvidia.spark.rapids.Arm.withResourceIfAllowed
-//import com.nvidia.spark.rapids.RapidsPluginImplicits.ReallyAGpuExpression
-//import com.nvidia.spark.rapids.jni.HLL
+import com.nvidia.spark.rapids.Arm.withResourceIfAllowed
+import com.nvidia.spark.rapids.RapidsPluginImplicits.ReallyAGpuExpression
+import com.nvidia.spark.rapids.jni.HLL
 import com.nvidia.spark.rapids.shims.ShimExpression
 
 import org.apache.spark.sql.catalyst.expressions.{AttributeReference, Expression}
@@ -57,7 +57,7 @@ case class CudfMergeHLLPP(override val dataType: DataType,
  * Perform the final evaluation step to compute approximate count distinct from sketches.
  * Input is long columns, first construct struct of long then feed to cuDF
  */
-case class GpuHyperLogLogPlusPlusEvaluation(children: Seq[Expression],
+case class GpuHyperLogLogPlusPlusEvaluation(childExpr: Expression,
     numRegistersPerSketch: Int)
     extends GpuExpression with ShimExpression {
   override def dataType: DataType = LongType
@@ -66,19 +66,14 @@ case class GpuHyperLogLogPlusPlusEvaluation(children: Seq[Expression],
 
   override def nullable: Boolean = false
 
-  override def columnarEval(batch: ColumnarBatch): GpuColumnVector = {
+  override def children: scala.Seq[Expression] = Seq(childExpr)
 
-    // TODO
-    //    withResourceIfAllowed(childExpr.columnarEval(batch)) { sketches =>
-    //      val distinctValues = HLL.estimateDistinctValueFromSketches(
-    //      sketches.getBase, numRegistersPerSketch)
-    //      GpuColumnVector.from(distinctValues, LongType)
-    //    }
-
-    val numRows = batch.numRows()
-    val zeros = Array.fill(numRows)(0L)
-    val longCv = ColumnVector.fromLongs(zeros: _*)
-    GpuColumnVector.from(longCv, LongType)
+  override def columnarEval(batch: ColumnarBatch): GpuColumnVector = {
+    withResourceIfAllowed(childExpr.columnarEval(batch)) { sketches =>
+      val distinctValues = HLL.estimateDistinctValueFromSketches(
+      sketches.getBase, numRegistersPerSketch)
+      GpuColumnVector.from(distinctValues, LongType)
+    }
   }
 }
 
@@ -160,7 +155,7 @@ case class GpuHyperLogLogPlusPlus(childExpr: Expression, relativeSD: Double)
   }
 
   override lazy val evaluateExpression: Expression =
-    GpuHyperLogLogPlusPlusEvaluation(aggBufferAttributes, numRegistersPerSketch)
+    GpuHyperLogLogPlusPlusEvaluation(genStruct.head, numRegistersPerSketch)
 
   override def dataType: DataType = LongType