perf[ext]: pushdown filter + constant

Signed-off-by: Joe Isaacs <[email protected]>

Author: joseph-isaacs

vortex-array/src/arrays/extension/vtable/mod.rs

@@ -4,6 +4,7 @@
 mod array;
 mod canonical;
 mod operations;
+mod rules;
 mod validity;
 mod visitor;
 
@@ -19,6 +20,7 @@ use crate::ArrayRef;
 use crate::EmptyMetadata;
 use crate::VectorExecutor;
 use crate::arrays::extension::ExtensionArray;
+use crate::arrays::extension::vtable::rules::PARENT_RULES;
 use crate::executor::ExecutionCtx;
 use crate::serde::ArrayChildren;
 use crate::vtable;
@@ -98,6 +100,14 @@ impl VTable for ExtensionVTable {
     fn execute(array: &Self::Array, ctx: &mut ExecutionCtx) -> VortexResult<Vector> {
         array.storage().execute(ctx)
     }
+
+    fn reduce_parent(
+        array: &Self::Array,
+        parent: &ArrayRef,
+        child_idx: usize,
+    ) -> VortexResult<Option<ArrayRef>> {
+        PARENT_RULES.evaluate(array, parent, child_idx)
+    }
 }
 
 #[derive(Debug)]

vortex-array/src/arrays/extension/vtable/rules.rs

@@ -0,0 +1,345 @@
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-FileCopyrightText: Copyright the Vortex contributors
+
+use vortex_error::VortexResult;
+
+use crate::Array;
+use crate::ArrayRef;
+use crate::IntoArray;
+use crate::arrays::AnyScalarFn;
+use crate::arrays::ConstantArray;
+use crate::arrays::ConstantVTable;
+use crate::arrays::ExtensionArray;
+use crate::arrays::ExtensionVTable;
+use crate::arrays::FilterArray;
+use crate::arrays::FilterVTable;
+use crate::arrays::ScalarFnArray;
+use crate::matchers::Exact;
+use crate::optimizer::rules::ArrayParentReduceRule;
+use crate::optimizer::rules::ParentRuleSet;
+
+pub(super) const PARENT_RULES: ParentRuleSet<ExtensionVTable> = ParentRuleSet::new(&[
+    ParentRuleSet::lift(&ExtensionFilterPushDownRule),
+    ParentRuleSet::lift(&ExtensionScalarFnConstantPushDownRule),
+]);
+
+/// Push filter operations into the storage array of an extension array.
+#[derive(Debug)]
+struct ExtensionFilterPushDownRule;
+
+impl ArrayParentReduceRule<ExtensionVTable> for ExtensionFilterPushDownRule {
+    type Parent = Exact<FilterVTable>;
+
+    fn parent(&self) -> Self::Parent {
+        Exact::from(&FilterVTable)
+    }
+
+    fn reduce_parent(
+        &self,
+        child: &ExtensionArray,
+        parent: &FilterArray,
+        _child_idx: usize,
+    ) -> VortexResult<Option<ArrayRef>> {
+        let filtered_storage = child
+            .storage()
+            .clone()
+            .filter(parent.filter_mask().clone())?;
+        Ok(Some(
+            ExtensionArray::new(child.ext_dtype().clone(), filtered_storage).into_array(),
+        ))
+    }
+}
+
+/// Push scalar function operations into the storage array when the other operand is a constant
+/// with the same extension type.
+#[derive(Debug)]
+struct ExtensionScalarFnConstantPushDownRule;
+
+impl ArrayParentReduceRule<ExtensionVTable> for ExtensionScalarFnConstantPushDownRule {
+    type Parent = AnyScalarFn;
+
+    fn parent(&self) -> Self::Parent {
+        AnyScalarFn
+    }
+
+    fn reduce_parent(
+        &self,
+        child: &ExtensionArray,
+        parent: &ScalarFnArray,
+        child_idx: usize,
+    ) -> VortexResult<Option<ArrayRef>> {
+        // Check that all other children are constants with matching extension types.
+        for (idx, sibling) in parent.children().iter().enumerate() {
+            if idx == child_idx {
+                continue;
+            }
+
+            // Sibling must be a constant.
+            let Some(const_array) = sibling.as_opt::<ConstantVTable>() else {
+                return Ok(None);
+            };
+
+            // Sibling must be an extension scalar with the same extension type.
+            let Some(ext_scalar) = const_array.scalar().as_extension_opt() else {
+                return Ok(None);
+            };
+
+            if !ext_scalar
+                .ext_dtype()
+                .eq_ignore_nullability(child.ext_dtype())
+            {
+                return Ok(None);
+            }
+
+            // The storage dtype must match.
+            if !ext_scalar
+                .ext_dtype()
+                .storage_dtype()
+                .eq_ignore_nullability(child.ext_dtype().storage_dtype())
+            {
+                return Ok(None);
+            }
+        }
+
+        // Build new children with storage arrays/scalars.
+        let mut new_children = Vec::with_capacity(parent.children().len());
+        for (idx, sibling) in parent.children().iter().enumerate() {
+            if idx == child_idx {
+                new_children.push(child.storage().clone());
+            } else {
+                let const_array = sibling.as_::<ConstantVTable>();
+                let storage_scalar = const_array.scalar().as_extension().storage();
+                new_children.push(ConstantArray::new(storage_scalar, child.len()).into_array());
+            }
+        }
+
+        Ok(Some(
+            ScalarFnArray::try_new(parent.scalar_fn().clone(), new_children, child.len())?
+                .into_array(),
+        ))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::sync::Arc;
+
+    use vortex_buffer::buffer;
+    use vortex_dtype::DType;
+    use vortex_dtype::ExtDType;
+    use vortex_dtype::ExtID;
+    use vortex_dtype::Nullability;
+    use vortex_dtype::PType;
+    use vortex_mask::Mask;
+    use vortex_scalar::Scalar;
+
+    use crate::Array;
+    use crate::IntoArray;
+    use crate::ToCanonical;
+    use crate::arrays::ConstantArray;
+    use crate::arrays::ExtensionArray;
+    use crate::arrays::ExtensionVTable;
+    use crate::arrays::FilterArray;
+    use crate::arrays::PrimitiveArray;
+    use crate::arrays::PrimitiveVTable;
+    use crate::arrays::ScalarFnArrayExt;
+    use crate::expr::Binary;
+    use crate::expr::Operator;
+    use crate::optimizer::ArrayOptimizer;
+
+    fn test_ext_dtype() -> Arc<ExtDType> {
+        Arc::new(ExtDType::new(
+            ExtID::new("test_ext".into()),
+            Arc::new(DType::Primitive(PType::I64, Nullability::NonNullable)),
+            None,
+        ))
+    }
+
+    #[test]
+    fn test_filter_pushdown() {
+        let ext_dtype = test_ext_dtype();
+        let storage = buffer![1i64, 2, 3, 4, 5].into_array();
+        let ext_array = ExtensionArray::new(ext_dtype.clone(), storage).into_array();
+
+        // Create a filter that selects elements at indices 0, 2, 4
+        let mask = Mask::from_iter([true, false, true, false, true]);
+        let filter_array = FilterArray::new(ext_array, mask).into_array();
+
+        // Optimize should push the filter into the storage
+        let optimized = filter_array.optimize().unwrap();
+
+        // The result should be an ExtensionArray, not a FilterArray
+        assert!(
+            optimized.as_opt::<ExtensionVTable>().is_some(),
+            "Expected ExtensionArray after optimization, got {}",
+            optimized.encoding_id()
+        );
+
+        let ext_result = optimized.as_::<ExtensionVTable>();
+        assert_eq!(ext_result.len(), 3);
+        assert_eq!(ext_result.ext_dtype().as_ref(), ext_dtype.as_ref());
+
+        // Check the storage values
+        let storage_result: &[i64] = &ext_result.storage().to_primitive().buffer::<i64>();
+        assert_eq!(storage_result, &[1, 3, 5]);
+    }
+
+    #[test]
+    fn test_filter_pushdown_nullable() {
+        let ext_dtype = Arc::new(ExtDType::new(
+            ExtID::new("test_ext".into()),
+            Arc::new(DType::Primitive(PType::I64, Nullability::Nullable)),
+            None,
+        ));
+        let storage = PrimitiveArray::from_option_iter([Some(1i64), None, Some(3), Some(4), None])
+            .into_array();
+        let ext_array = ExtensionArray::new(ext_dtype, storage).into_array();
+
+        let mask = Mask::from_iter([true, true, false, false, true]);
+        let filter_array = FilterArray::new(ext_array, mask).into_array();
+
+        let optimized = filter_array.optimize().unwrap();
+
+        assert!(optimized.as_opt::<ExtensionVTable>().is_some());
+        let ext_result = optimized.as_::<ExtensionVTable>();
+        assert_eq!(ext_result.len(), 3);
+
+        // Check values: should be [Some(1), None, None]
+        let canonical = ext_result.storage().to_primitive();
+        assert_eq!(canonical.len(), 3);
+    }
+
+    #[test]
+    fn test_scalar_fn_constant_pushdown_comparison() {
+        let ext_dtype = test_ext_dtype();
+        let storage = buffer![10i64, 20, 30, 40, 50].into_array();
+        let ext_array = ExtensionArray::new(ext_dtype.clone(), storage).into_array();
+
+        // Create a constant extension scalar with value 25
+        let const_scalar = Scalar::extension(ext_dtype, Scalar::from(25i64));
+        let const_array = ConstantArray::new(const_scalar, 5).into_array();
+
+        // Create a binary comparison: ext_array < const_array
+        let scalar_fn_array = Binary
+            .try_new_array(5, Operator::Lt, [ext_array, const_array])
+            .unwrap();
+
+        // Optimize should push down the comparison to storage
+        let optimized = scalar_fn_array.optimize().unwrap();
+
+        // The result should still be a ScalarFnArray but operating on primitive storage
+        let scalar_fn = optimized.as_opt::<crate::arrays::ScalarFnVTable>();
+        assert!(
+            scalar_fn.is_some(),
+            "Expected ScalarFnArray after optimization"
+        );
+
+        // The children should now be primitives, not extensions
+        let children = scalar_fn.unwrap().children();
+        assert_eq!(children.len(), 2);
+
+        // First child should be the primitive storage
+        assert!(
+            children[0].as_opt::<PrimitiveVTable>().is_some(),
+            "Expected first child to be PrimitiveArray, got {}",
+            children[0].encoding_id()
+        );
+
+        // Second child should be a constant with primitive value
+        assert!(
+            children[1]
+                .as_opt::<crate::arrays::ConstantVTable>()
+                .is_some(),
+            "Expected second child to be ConstantArray, got {}",
+            children[1].encoding_id()
+        );
+    }
+
+    #[test]
+    fn test_scalar_fn_no_pushdown_different_ext_types() {
+        let ext_dtype1 = Arc::new(ExtDType::new(
+            ExtID::new("type1".into()),
+            Arc::new(DType::Primitive(PType::I64, Nullability::NonNullable)),
+            None,
+        ));
+        let ext_dtype2 = Arc::new(ExtDType::new(
+            ExtID::new("type2".into()),
+            Arc::new(DType::Primitive(PType::I64, Nullability::NonNullable)),
+            None,
+        ));
+
+        let storage = buffer![10i64, 20, 30].into_array();
+        let ext_array = ExtensionArray::new(ext_dtype1, storage).into_array();
+
+        // Create constant with different extension type
+        let const_scalar = Scalar::extension(ext_dtype2, Scalar::from(25i64));
+        let const_array = ConstantArray::new(const_scalar, 3).into_array();
+
+        let scalar_fn_array = Binary
+            .try_new_array(3, Operator::Lt, [ext_array.clone(), const_array])
+            .unwrap();
+
+        let optimized = scalar_fn_array.optimize().unwrap();
+
+        // The first child should still be an ExtensionArray (no pushdown happened)
+        let scalar_fn = optimized.as_opt::<crate::arrays::ScalarFnVTable>().unwrap();
+        assert!(
+            scalar_fn.children()[0]
+                .as_opt::<ExtensionVTable>()
+                .is_some(),
+            "Expected first child to remain ExtensionArray when ext types differ"
+        );
+    }
+
+    #[test]
+    fn test_scalar_fn_no_pushdown_non_constant_sibling() {
+        let ext_dtype = test_ext_dtype();
+
+        let storage1 = buffer![10i64, 20, 30].into_array();
+        let ext_array1 = ExtensionArray::new(ext_dtype.clone(), storage1).into_array();
+
+        let storage2 = buffer![15i64, 25, 35].into_array();
+        let ext_array2 = ExtensionArray::new(ext_dtype, storage2).into_array();
+
+        // Both children are extension arrays (not constants)
+        let scalar_fn_array = Binary
+            .try_new_array(3, Operator::Lt, [ext_array1.clone(), ext_array2])
+            .unwrap();
+
+        let optimized = scalar_fn_array.optimize().unwrap();
+
+        // No pushdown should happen because sibling is not a constant
+        let scalar_fn = optimized.as_opt::<crate::arrays::ScalarFnVTable>().unwrap();
+        assert!(
+            scalar_fn.children()[0]
+                .as_opt::<ExtensionVTable>()
+                .is_some(),
+            "Expected first child to remain ExtensionArray when sibling is not constant"
+        );
+    }
+
+    #[test]
+    fn test_scalar_fn_no_pushdown_non_extension_constant() {
+        let ext_dtype = test_ext_dtype();
+        let storage = buffer![10i64, 20, 30].into_array();
+        let ext_array = ExtensionArray::new(ext_dtype, storage).into_array();
+
+        // Create a non-extension constant (plain primitive)
+        let const_array = ConstantArray::new(Scalar::from(25i64), 3).into_array();
+
+        let scalar_fn_array = Binary
+            .try_new_array(3, Operator::Lt, [ext_array.clone(), const_array])
+            .unwrap();
+
+        let optimized = scalar_fn_array.optimize().unwrap();
+
+        // No pushdown should happen because constant is not an extension scalar
+        let scalar_fn = optimized.as_opt::<crate::arrays::ScalarFnVTable>().unwrap();
+        assert!(
+            scalar_fn.children()[0]
+                .as_opt::<ExtensionVTable>()
+                .is_some(),
+            "Expected first child to remain ExtensionArray when constant is not extension"
+        );
+    }
+}