crates/core_arch/src/x86/macros.rs

//! Utility macros.

macro_rules! constify_imm6 {
    ($imm8:expr, $expand:ident) => {
        #[allow(overflowing_literals)]
        match ($imm8) & 0b1_1111 {
            0 => $expand!(0),
            1 => $expand!(1),
            2 => $expand!(2),
            3 => $expand!(3),
            4 => $expand!(4),
            5 => $expand!(5),
            6 => $expand!(6),
            7 => $expand!(7),
            8 => $expand!(8),
            9 => $expand!(9),
            10 => $expand!(10),
            11 => $expand!(11),
            12 => $expand!(12),
            13 => $expand!(13),
            14 => $expand!(14),
            15 => $expand!(15),
            16 => $expand!(16),
            17 => $expand!(17),
            18 => $expand!(18),
            19 => $expand!(19),
            20 => $expand!(20),
            21 => $expand!(21),
            22 => $expand!(22),
            23 => $expand!(23),
            24 => $expand!(24),
            25 => $expand!(25),
            26 => $expand!(26),
            27 => $expand!(27),
            28 => $expand!(28),
            29 => $expand!(29),
            30 => $expand!(30),
            _ => $expand!(31),
        }
    };
}

macro_rules! constify_imm4 {
    ($imm8:expr, $expand:ident) => {
        #[allow(overflowing_literals)]
        match ($imm8) & 0b1111 {
            0 => $expand!(0),
            1 => $expand!(1),
            2 => $expand!(2),
            3 => $expand!(3),
            4 => $expand!(4),
            5 => $expand!(5),
            6 => $expand!(6),
            7 => $expand!(7),
            8 => $expand!(8),
            9 => $expand!(9),
            10 => $expand!(10),
            11 => $expand!(11),
            12 => $expand!(12),
            13 => $expand!(13),
            14 => $expand!(14),
            _ => $expand!(15),
        }
    };
}

macro_rules! constify_imm3 {
    ($imm8:expr, $expand:ident) => {
        #[allow(overflowing_literals)]
        match ($imm8) & 0b111 {
            0 => $expand!(0),
            1 => $expand!(1),
            2 => $expand!(2),
            3 => $expand!(3),
            4 => $expand!(4),
            5 => $expand!(5),
            6 => $expand!(6),
            _ => $expand!(7),
        }
    };
}

macro_rules! constify_imm2 {
    ($imm8:expr, $expand:ident) => {
        #[allow(overflowing_literals)]
        match ($imm8) & 0b11 {
            0 => $expand!(0),
            1 => $expand!(1),
            2 => $expand!(2),
            _ => $expand!(3),
        }
    };
}

#[cfg(test)]
macro_rules! assert_approx_eq {
    ($a:expr, $b:expr, $eps:expr) => {{
        let (a, b) = (&$a, &$b);
        assert!(
            (*a - *b).abs() < $eps,
            "assertion failed: `(left !== right)` \
             (left: `{:?}`, right: `{:?}`, expect diff: `{:?}`, real diff: `{:?}`)",
            *a,
            *b,
            $eps,
            (*a - *b).abs()
        );
    }};
}