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
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103

/// Encode an integer as a bitmask for the opcode.
#[macro_export]
macro_rules! encode_opcode {
    ($n:expr) => {
        (($n as u32) & 0b0111_1111)
    };
}

/// Encode a register number as a bitmask for rd.
#[macro_export]
macro_rules! encode_rd {
    ($n:expr) => {
        (($n as u32) << 7)
    };
}

/// Encode a register number as a bitmask for rs1.
#[macro_export]
macro_rules! encode_rs1 {
    ($n:expr) => {
        (($n as u32) << 15)
    };
}

/// Encode a register number as a bitmask for rs2.
#[macro_export]
macro_rules! encode_rs2 {
    ($n:expr) => {
        (($n as u32) << 20)
    };
}

/// Encode an integer as a bitmask for func3.
#[macro_export]
macro_rules! encode_func3 {
    ($n: expr) => {
        (($n as u32) << 12)
    };
}

/// Encode an integer as a bitmask for func7.
#[macro_export]
macro_rules! encode_func7 {
    ($n: expr) => {
        (($n as u32) << 25)
    };
}

/// Encode and integer as a bitmask for an I-type immediate.
#[macro_export]
macro_rules! encode_i_imm {
    ($n:expr) => {{
        let n_bits = ($n & 0xFFF) as u32;
        let mut res: u32 = 0;
        res |= (n_bits as u32) << 20;
        let sign_bit = if (($n as u32) & lib_rv32_common::bit!(31)) != 0 {
            1
        } else {
            0
        };
        res |= sign_bit << 31;
        res
    }};
}

/// Encode and integer as a bitmask for a J-type immediate.
#[macro_export]
macro_rules! encode_j_imm {
    ($n:expr) => {
        (((($n as u32) & 0b10000000_00000000_00000000_00000000) << (31 - 31))
            | ((($n as u32) & 0b00000000_00001111_11110000_00000000) << (12 - 12))
            | ((($n as u32) & 0b00000000_00000000_00001000_00000000) << (20 - 11))
            | ((($n as u32) & 0b00000000_00000000_00000111_11100000) << (25 - 5))
            | ((($n as u32) & 0b00000000_00000000_00000000_00011110) << (21 - 1)))
    };
}

/// Encode and integer as a bitmask for a U-type immediate.
#[macro_export]
macro_rules! encode_u_imm {
    ($n:expr) => {
        (($n as u32) << 12)
    };
}

/// Encode and integer as a bitmask for an S-type immediate.
#[macro_export]
macro_rules! encode_s_imm {
    ($n:expr) => {
        (((($n as u32) & 0b111111100000) << 25) | ((($n as u32) & 0b000000011111) << 7))
    };
}

/// Encode and integer as a bitmask for a B-type immediate.
#[macro_export]
macro_rules! encode_b_imm {
    ($n:expr) => {
        (((($n as u32) & 0b10000000_00000000_00000000_00000000) << (31 - 31))
            | ((($n as u32) & 0b00000000_00000000_00000111_11100000) << (25 - 5))
            | ((($n as u32) & 0b00000000_00000000_00000000_00011110) << (8 - 1))
            | ((($n as u32) & 0b00000000_00000000_00001000_00000000) >> (11 - 7)))
    };
}