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luaur_vm/functions/
b_shift.rs

1use crate::functions::lua_pushunsigned::lua_pushunsigned;
2use crate::macros::nbits::NBITS;
3use crate::macros::trim::trim;
4use crate::type_aliases::b_uint::b_uint;
5use crate::type_aliases::lua_state::lua_State;
6
7pub fn b_shift(l: *mut lua_State, mut r: b_uint, mut i: core::ffi::c_int) -> core::ffi::c_int {
8    // Mirrors VM/src/lbitlib.cpp:b_shift
9    if i < 0 {
10        i = -i;
11        r = trim(r);
12        if i >= NBITS as core::ffi::c_int {
13            r = 0;
14        } else {
15            r >>= i as u32;
16        }
17    } else {
18        if i >= NBITS as core::ffi::c_int {
19            r = 0;
20        } else {
21            r <<= i as u32;
22        }
23        r = trim(r);
24    }
25
26    lua_pushunsigned(l, r);
27    1
28}