Optimize filter function performance with copyPositions

Before the change:
Benchmark                             (name)  Mode  Cnt   Score   Error  Units
BenchmarkArrayFilter.benchmark        filter  avgt   20  22.543 ± 0.979  ns/op
BenchmarkArrayFilter.benchmarkObject  filter  avgt   20  42.045 ± 2.088  ns/op

After the change:
Benchmark                             (name)  Mode  Cnt   Score   Error  Units
BenchmarkArrayFilter.benchmark        filter  avgt   20  13.327 ± 0.359  ns/op
BenchmarkArrayFilter.benchmarkObject  filter  avgt   20  34.443 ± 1.943  ns/op

core/trino-main/src/main/java/io/trino/operator/scalar/ArrayFilterFunction.java

@@ -14,7 +14,6 @@
 package io.trino.operator.scalar;
 
 import io.trino.spi.block.Block;
-import io.trino.spi.block.BlockBuilder;
 import io.trino.spi.function.Description;
 import io.trino.spi.function.ScalarFunction;
 import io.trino.spi.function.SqlType;
@@ -39,19 +38,22 @@ public static Block filterLong(
             @SqlType("function(T, boolean)") LongToBooleanFunction function)
     {
         int positionCount = arrayBlock.getPositionCount();
-        BlockBuilder resultBuilder = elementType.createBlockBuilder(null, positionCount);
+        int[] positions = new int[positionCount];
+        int length = 0;
         for (int position = 0; position < positionCount; position++) {
             Long input = null;
             if (!arrayBlock.isNull(position)) {
                 input = elementType.getLong(arrayBlock, position);
             }
 
             Boolean keep = function.apply(input);
-            if (TRUE.equals(keep)) {
-                elementType.appendTo(arrayBlock, position, resultBuilder);
-            }
+            positions[length] = position;
+            length += TRUE.equals(keep) ? 1 : 0;
+        }
+        if (positions.length == length) {
+            return arrayBlock;
         }
-        return resultBuilder.build();
+        return arrayBlock.copyPositions(positions, 0, length);
     }
 
     @TypeParameter("T")
@@ -63,19 +65,22 @@ public static Block filterDouble(
             @SqlType("function(T, boolean)") DoubleToBooleanFunction function)
     {
         int positionCount = arrayBlock.getPositionCount();
-        BlockBuilder resultBuilder = elementType.createBlockBuilder(null, positionCount);
+        int[] positions = new int[positionCount];
+        int length = 0;
         for (int position = 0; position < positionCount; position++) {
             Double input = null;
             if (!arrayBlock.isNull(position)) {
                 input = elementType.getDouble(arrayBlock, position);
             }
 
             Boolean keep = function.apply(input);
-            if (TRUE.equals(keep)) {
-                elementType.appendTo(arrayBlock, position, resultBuilder);
-            }
+            positions[length] = position;
+            length += TRUE.equals(keep) ? 1 : 0;
+        }
+        if (positions.length == length) {
+            return arrayBlock;
         }
-        return resultBuilder.build();
+        return arrayBlock.copyPositions(positions, 0, length);
     }
 
     @TypeParameter("T")
@@ -87,19 +92,22 @@ public static Block filterBoolean(
             @SqlType("function(T, boolean)") BooleanToBooleanFunction function)
     {
         int positionCount = arrayBlock.getPositionCount();
-        BlockBuilder resultBuilder = elementType.createBlockBuilder(null, positionCount);
+        int[] positions = new int[positionCount];
+        int length = 0;
         for (int position = 0; position < positionCount; position++) {
             Boolean input = null;
             if (!arrayBlock.isNull(position)) {
                 input = elementType.getBoolean(arrayBlock, position);
             }
 
             Boolean keep = function.apply(input);
-            if (TRUE.equals(keep)) {
-                elementType.appendTo(arrayBlock, position, resultBuilder);
-            }
+            positions[length] = position;
+            length += TRUE.equals(keep) ? 1 : 0;
+        }
+        if (positions.length == length) {
+            return arrayBlock;
         }
-        return resultBuilder.build();
+        return arrayBlock.copyPositions(positions, 0, length);
     }
 
     @TypeParameter("T")
@@ -111,18 +119,21 @@ public static Block filterObject(
             @SqlType("function(T, boolean)") ObjectToBooleanFunction function)
     {
         int positionCount = arrayBlock.getPositionCount();
-        BlockBuilder resultBuilder = elementType.createBlockBuilder(null, positionCount);
+        int[] positions = new int[positionCount];
+        int length = 0;
         for (int position = 0; position < positionCount; position++) {
             Object input = null;
             if (!arrayBlock.isNull(position)) {
                 input = elementType.getObject(arrayBlock, position);
             }
 
             Boolean keep = function.apply(input);
-            if (TRUE.equals(keep)) {
-                elementType.appendTo(arrayBlock, position, resultBuilder);
-            }
+            positions[length] = position;
+            length += TRUE.equals(keep) ? 1 : 0;
+        }
+        if (positions.length == length) {
+            return arrayBlock;
         }
-        return resultBuilder.build();
+        return arrayBlock.copyPositions(positions, 0, length);
     }
 }