1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66

use p3_air::AirBuilder;
use p3_field::AbstractField;
use p3_field::Field;
use sp1_derive::AlignedBorrow;

use crate::air::SP1AirBuilder;
use crate::air::Word;
use crate::bytes::event::ByteRecord;
use crate::bytes::ByteOpcode;
use crate::disassembler::WORD_SIZE;

/// A set of columns needed to compute the not of a word.
#[derive(AlignedBorrow, Default, Debug, Clone, Copy)]
#[repr(C)]
pub struct NotOperation<T> {
    /// The result of `!x`.
    pub value: Word<T>,
}

impl<F: Field> NotOperation<F> {
    pub fn populate(
        &mut self,
        record: &mut impl ByteRecord,
        shard: u32,
        channel: u32,
        x: u32,
    ) -> u32 {
        let expected = !x;
        let x_bytes = x.to_le_bytes();
        for i in 0..WORD_SIZE {
            self.value[i] = F::from_canonical_u8(!x_bytes[i]);
        }
        record.add_u8_range_checks(shard, channel, &x_bytes);
        expected
    }

    #[allow(unused_variables)]
    pub fn eval<AB: SP1AirBuilder>(
        builder: &mut AB,
        a: Word<AB::Var>,
        cols: NotOperation<AB::Var>,
        shard: impl Into<AB::Expr> + Copy,
        channel: impl Into<AB::Expr> + Copy,
        is_real: impl Into<AB::Expr> + Copy,
    ) {
        for i in (0..WORD_SIZE).step_by(2) {
            builder.send_byte_pair(
                AB::F::from_canonical_u32(ByteOpcode::U8Range as u32),
                AB::F::zero(),
                AB::F::zero(),
                a[i],
                a[i + 1],
                shard,
                channel,
                is_real,
            );
        }

        // For any byte b, b + !b = 0xFF.
        for i in 0..WORD_SIZE {
            builder
                .when(is_real)
                .assert_eq(cols.value[i] + a[i], AB::F::from_canonical_u8(u8::MAX));
        }
    }
}