vortex-fastlanes 0.65.0

Vortex fastlanes arrays
Documentation 
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// SPDX-License-Identifier: Apache-2.0
// SPDX-FileCopyrightText: Copyright the Vortex contributors

use std::cmp::min;
use std::ops::Range;

use vortex_array::ArrayRef;
use vortex_array::IntoArray;
use vortex_array::arrays::slice::SliceReduce;
use vortex_error::VortexResult;

use crate::DeltaArray;
use crate::delta::vtable::Delta;

impl SliceReduce for Delta {
    fn slice(array: &Self::Array, range: Range<usize>) -> VortexResult<Option<ArrayRef>> {
        let physical_start = range.start + array.offset();
        let physical_stop = range.end + array.offset();

        let start_chunk = physical_start / 1024;
        let stop_chunk = physical_stop.div_ceil(1024);

        let bases = array.bases();
        let deltas = array.deltas();
        let lanes = array.lanes();

        let new_bases = bases.slice(
            min(start_chunk * lanes, array.bases_len())..min(stop_chunk * lanes, array.bases_len()),
        )?;

        let new_deltas = deltas.slice(
            min(start_chunk * 1024, array.deltas_len())..min(stop_chunk * 1024, array.deltas_len()),
        )?;

        // SAFETY: slicing valid bases/deltas preserves correctness
        Ok(Some(unsafe {
            DeltaArray::new_unchecked(new_bases, new_deltas, physical_start % 1024, range.len())
                .into_array()
        }))
    }
}