luaur-vm 0.1.0

The Luau register virtual machine and standard library (Rust).
Documentation 
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use crate::enums::lua_type::lua_Type;
use crate::macros::luai_num_2_unsigned::luai_num2unsigned;
use crate::macros::nvalue::nvalue;
use crate::macros::setnvalue::setnvalue;
use crate::macros::ttisnumber::ttisnumber;
use crate::type_aliases::lua_state::lua_State;
use crate::type_aliases::stk_id::StkId;
use crate::type_aliases::t_value::TValue;

#[allow(non_snake_case)]
pub unsafe fn luau_f_lshift(
    _L: *mut lua_State,
    res: StkId,
    arg0: *mut TValue,
    nresults: core::ffi::c_int,
    args: StkId,
    nparams: core::ffi::c_int,
) -> core::ffi::c_int {
    if nparams >= 2 && nresults <= 1 && ttisnumber!(arg0) && ttisnumber!(args) {
        let a1 = nvalue!(arg0);
        let a2 = nvalue!(args);

        let mut u: u32 = 0;
        luai_num2unsigned(&mut u, a1);
        let s = a2 as i32;

        // note: we only specialize fast-path that doesn't require further conditionals (negative shifts and shifts greater or equal to bit width can
        // be handled generically)
        if (s as u32) < 32 {
            let r = u << s;

            setnvalue!(res, r as f64);
            return 1;
        }
    }

    -1
}