luaur-code-gen 0.1.1

Native (A64/X64) code generation for Luau (Rust).
Documentation 
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pub fn get_fmov_imm_fp_32(value: f32) -> i32 {
    let u = value.to_bits();

    // positive 0 is encodable via movi
    if u == 0 {
        return 256;
    }

    // early out: fmov can only encode float with 19 least significant zeros
    if (u & ((1u32 << 19) - 1)) != 0 {
        return -1;
    }

    // f32 expansion is abcdfegh => aBbbbbbc defgh000 00000000 00000000
    let imm = ((u >> 24) as i32 & 0x80) | ((u >> 19) as i32 & 0x7f);
    let dec = ((imm & 0x80) << 5)
        | (if (imm & 0x40) != 0 {
            0b00000111_11000000
        } else {
            0b00001000_00000000
        })
        | (imm & 0x3f);

    if dec == (u >> 19) as i32 {
        imm
    } else {
        -1
    }
}