Function lower_while_loop 

pub fn lower_while_loop<'db>(
    ctx: &mut LoweringContext<'db, '_>,
    builder: &mut BlockBuilder<'db>,
    loop_expr: ExprWhile<'db>,
    loop_expr_id: ExprId,
) -> LoweringResult<'db, LoweredExpr<'db>>

Lowers an expression of type semantic::ExprWhile.