BooleanBufferBuilder::append_packed (#1038) (#1039)

* BooleanBufferBuilder::append_packed (#1038)

* Update docstring

* Add packed_append_range

* Fix capacity

* Use set_bits from transform::util

* Add license

* Format

arrow/Cargo.toml

@@ -104,6 +104,10 @@ harness = false
 name = "boolean_kernels"
 harness = false
 
+[[bench]]
+name = "boolean_append_packed"
+harness = false
+
 [[bench]]
 name = "arithmetic_kernels"
 harness = false

arrow/benches/boolean_append_packed.rs

@@ -0,0 +1,55 @@
+// 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.
+
+use arrow::array::BooleanBufferBuilder;
+use criterion::{criterion_group, criterion_main, Criterion};
+use rand::{thread_rng, Rng};
+
+fn rand_bytes(len: usize) -> Vec<u8> {
+    let mut rng = thread_rng();
+    let mut buf = vec![0_u8; len];
+    rng.fill(buf.as_mut_slice());
+    buf
+}
+
+fn boolean_append_packed(c: &mut Criterion) {
+    let mut rng = thread_rng();
+    let source = rand_bytes(1024);
+    let ranges: Vec<_> = (0..100)
+        .into_iter()
+        .map(|_| {
+            let start: usize = rng.gen_range(0..1024 * 8);
+            let end: usize = rng.gen_range(start..1024 * 8);
+            start..end
+        })
+        .collect();
+
+    let total_bits: usize = ranges.iter().map(|x| x.end - x.start).sum();
+
+    c.bench_function("boolean_append_packed", |b| {
+        b.iter(|| {
+            let mut buffer = BooleanBufferBuilder::new(total_bits);
+            for range in &ranges {
+                buffer.append_packed_range(range.clone(), &source);
+            }
+            assert_eq!(buffer.len(), total_bits);
+        })
+    });
+}
+
+criterion_group!(benches, boolean_append_packed);
+criterion_main!(benches);

arrow/src/array/builder.rs

@@ -25,6 +25,7 @@ use std::collections::HashMap;
 use std::fmt;
 use std::marker::PhantomData;
 use std::mem;
+use std::ops::Range;
 use std::sync::Arc;
 
 use crate::array::*;
@@ -398,6 +399,26 @@ impl BooleanBufferBuilder {
         }
     }
 
+    /// Append `range` bits from `to_set`
+    ///
+    /// `to_set` is a slice of bits packed LSB-first into `[u8]`
+    ///
+    /// # Panics
+    ///
+    /// Panics if `to_set` does not contain `ceil(range.end / 8)` bytes
+    pub fn append_packed_range(&mut self, range: Range<usize>, to_set: &[u8]) {
+        let offset_write = self.len;
+        let len = range.end - range.start;
+        self.advance(len);
+        crate::util::bit_mask::set_bits(
+            self.buffer.as_slice_mut(),
+            to_set,
+            offset_write,
+            range.start,
+            len,
+        );
+    }
+
     #[inline]
     pub fn finish(&mut self) -> Buffer {
         let buf = std::mem::replace(&mut self.buffer, MutableBuffer::new(0));
@@ -2843,6 +2864,42 @@ mod tests {
         assert!(buffer.get_bit(11));
     }
 
+    #[test]
+    fn test_bool_buffer_fuzz() {
+        use rand::prelude::*;
+
+        let mut buffer = BooleanBufferBuilder::new(12);
+        let mut all_bools = vec![];
+        let mut rng = rand::thread_rng();
+
+        let src_len = 32;
+        let (src, compacted_src) = {
+            let src: Vec<_> = std::iter::from_fn(|| Some(rng.next_u32() & 1 == 0))
+                .take(src_len)
+                .collect();
+
+            let mut compacted_src = BooleanBufferBuilder::new(src_len);
+            compacted_src.append_slice(&src);
+            (src, compacted_src.finish())
+        };
+
+        for _ in 0..100 {
+            let a = rng.next_u32() as usize % src_len;
+            let b = rng.next_u32() as usize % src_len;
+
+            let start = a.min(b);
+            let end = a.max(b);
+
+            buffer.append_packed_range(start..end, compacted_src.as_slice());
+            all_bools.extend_from_slice(&src[start..end]);
+        }
+
+        let mut compacted = BooleanBufferBuilder::new(all_bools.len());
+        compacted.append_slice(&all_bools);
+
+        assert_eq!(buffer.finish(), compacted.finish())
+    }
+
     #[test]
     fn test_boolean_array_builder_append_slice() {
         let arr1 =

arrow/src/array/transform/boolean.rs

@@ -15,12 +15,9 @@
 // specific language governing permissions and limitations
 // under the License.
 
+use super::{Extend, _MutableArrayData, utils::resize_for_bits};
 use crate::array::ArrayData;
-
-use super::{
-    Extend, _MutableArrayData,
-    utils::{resize_for_bits, set_bits},
-};
+use crate::util::bit_mask::set_bits;
 
 pub(super) fn build_extend(array: &ArrayData) -> Extend {
     let values = array.buffers()[0].as_slice();

arrow/src/array/transform/mod.rs

@@ -97,7 +97,7 @@ fn build_extend_null_bits(array: &ArrayData, use_nulls: bool) -> ExtendNullBits
         let bytes = bitmap.bits.as_slice();
         Box::new(move |mutable, start, len| {
             utils::resize_for_bits(&mut mutable.null_buffer, mutable.len + len);
-            mutable.null_count += utils::set_bits(
+            mutable.null_count += crate::util::bit_mask::set_bits(
                 mutable.null_buffer.as_slice_mut(),
                 bytes,
                 mutable.len,

arrow/src/array/transform/utils.rs

@@ -15,14 +15,7 @@
 // specific language governing permissions and limitations
 // under the License.
 
-use crate::{
-    array::OffsetSizeTrait,
-    buffer::MutableBuffer,
-    util::{
-        bit_chunk_iterator::BitChunks,
-        bit_util::{self, ceil},
-    },
-};
+use crate::{array::OffsetSizeTrait, buffer::MutableBuffer, util::bit_util};
 
 /// extends the `buffer` to be able to hold `len` bits, setting all bits of the new size to zero.
 #[inline]
@@ -33,49 +26,6 @@ pub(super) fn resize_for_bits(buffer: &mut MutableBuffer, len: usize) {
     }
 }
 
-/// sets all bits on `write_data` on the range `[offset_write..offset_write+len]` to be equal to the
-/// bits on `data` on the range `[offset_read..offset_read+len]`
-/// returns the number of `0` bits `data[offset_read..offset_read+len]`
-pub(super) fn set_bits(
-    write_data: &mut [u8],
-    data: &[u8],
-    offset_write: usize,
-    offset_read: usize,
-    len: usize,
-) -> usize {
-    let mut null_count = 0;
-
-    let mut bits_to_align = offset_write % 8;
-    if bits_to_align > 0 {
-        bits_to_align = std::cmp::min(len, 8 - bits_to_align);
-    }
-    let mut write_byte_index = ceil(offset_write + bits_to_align, 8);
-
-    // Set full bytes provided by bit chunk iterator (which iterates in 64 bits at a time)
-    let chunks = BitChunks::new(data, offset_read + bits_to_align, len - bits_to_align);
-    chunks.iter().for_each(|chunk| {
-        null_count += chunk.count_zeros();
-        chunk.to_le_bytes().iter().for_each(|b| {
-            write_data[write_byte_index] = *b;
-            write_byte_index += 1;
-        })
-    });
-
-    // Set individual bits both to align write_data to a byte offset and the remainder bits not covered by the bit chunk iterator
-    let remainder_offset = len - chunks.remainder_len();
-    (0..bits_to_align)
-        .chain(remainder_offset..len)
-        .for_each(|i| {
-            if bit_util::get_bit(data, offset_read + i) {
-                bit_util::set_bit(write_data, offset_write + i);
-            } else {
-                null_count += 1;
-            }
-        });
-
-    null_count as usize
-}
-
 pub(super) fn extend_offsets<T: OffsetSizeTrait>(
     buffer: &mut MutableBuffer,
     mut last_offset: T,
@@ -104,130 +54,3 @@ pub(super) unsafe fn get_last_offset<T: OffsetSizeTrait>(
     debug_assert!(prefix.is_empty() && suffix.is_empty());
     *offsets.get_unchecked(offsets.len() - 1)
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_set_bits_aligned() {
-        let mut destination: Vec<u8> = vec![0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
-        let source: &[u8] = &[
-            0b11100111, 0b10100101, 0b10011001, 0b11011011, 0b11101011, 0b11000011,
-            0b11100111, 0b10100101,
-        ];
-
-        let destination_offset = 8;
-        let source_offset = 0;
-
-        let len = 64;
-
-        let expected_data: &[u8] = &[
-            0, 0b11100111, 0b10100101, 0b10011001, 0b11011011, 0b11101011, 0b11000011,
-            0b11100111, 0b10100101, 0,
-        ];
-        let expected_null_count = 24;
-        let result = set_bits(
-            destination.as_mut_slice(),
-            source,
-            destination_offset,
-            source_offset,
-            len,
-        );
-
-        assert_eq!(destination, expected_data);
-        assert_eq!(result, expected_null_count);
-    }
-
-    #[test]
-    fn test_set_bits_unaligned_destination_start() {
-        let mut destination: Vec<u8> = vec![0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
-        let source: &[u8] = &[
-            0b11100111, 0b10100101, 0b10011001, 0b11011011, 0b11101011, 0b11000011,
-            0b11100111, 0b10100101,
-        ];
-
-        let destination_offset = 3;
-        let source_offset = 0;
-
-        let len = 64;
-
-        let expected_data: &[u8] = &[
-            0b00111000, 0b00101111, 0b11001101, 0b11011100, 0b01011110, 0b00011111,
-            0b00111110, 0b00101111, 0b00000101, 0b00000000,
-        ];
-        let expected_null_count = 24;
-        let result = set_bits(
-            destination.as_mut_slice(),
-            source,
-            destination_offset,
-            source_offset,
-            len,
-        );
-
-        assert_eq!(destination, expected_data);
-        assert_eq!(result, expected_null_count);
-    }
-
-    #[test]
-    fn test_set_bits_unaligned_destination_end() {
-        let mut destination: Vec<u8> = vec![0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
-        let source: &[u8] = &[
-            0b11100111, 0b10100101, 0b10011001, 0b11011011, 0b11101011, 0b11000011,
-            0b11100111, 0b10100101,
-        ];
-
-        let destination_offset = 8;
-        let source_offset = 0;
-
-        let len = 62;
-
-        let expected_data: &[u8] = &[
-            0, 0b11100111, 0b10100101, 0b10011001, 0b11011011, 0b11101011, 0b11000011,
-            0b11100111, 0b00100101, 0,
-        ];
-        let expected_null_count = 23;
-        let result = set_bits(
-            destination.as_mut_slice(),
-            source,
-            destination_offset,
-            source_offset,
-            len,
-        );
-
-        assert_eq!(destination, expected_data);
-        assert_eq!(result, expected_null_count);
-    }
-
-    #[test]
-    fn test_set_bits_unaligned() {
-        let mut destination: Vec<u8> = vec![0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0];
-        let source: &[u8] = &[
-            0b11100111, 0b10100101, 0b10011001, 0b11011011, 0b11101011, 0b11000011,
-            0b11100111, 0b10100101, 0b10011001, 0b11011011, 0b11101011, 0b11000011,
-            0b11100111, 0b10100101, 0b10011001, 0b11011011, 0b11101011, 0b11000011,
-        ];
-
-        let destination_offset = 3;
-        let source_offset = 5;
-
-        let len = 95;
-
-        let expected_data: &[u8] = &[
-            0b01111000, 0b01101001, 0b11100110, 0b11110110, 0b11111010, 0b11110000,
-            0b01111001, 0b01101001, 0b11100110, 0b11110110, 0b11111010, 0b11110000,
-            0b00000001,
-        ];
-        let expected_null_count = 35;
-        let result = set_bits(
-            destination.as_mut_slice(),
-            source,
-            destination_offset,
-            source_offset,
-            len,
-        );
-
-        assert_eq!(destination, expected_data);
-        assert_eq!(result, expected_null_count);
-    }
-}