{"ast_node_type":"variable","tokens":[{"end":81,"kind":"keyword","start":0,"text":"let"}]}
    let high = fx.bcx.ins().band_imm(lhs_high, 0x7fff_ffff_ffff_ffff_u64 as i64);
    let (_, rhs_high) = fx.bcx.ins().isplit(rhs);
    let sign = fx.bcx.ins().band_imm(rhs_high, 0x8000_0000_0000_0000_u64 as i64);