1 use rustc_middle::mir::visit::Visitor;
2 use rustc_middle::mir::{Constant, ConstantKind, Location};
3 use rustc_middle::ty::ConstKind;
5 pub struct RequiredConstsVisitor<'a, 'tcx> {
6 required_consts: &'a mut Vec<Constant<'tcx>>,
9 impl<'a, 'tcx> RequiredConstsVisitor<'a, 'tcx> {
10 pub fn new(required_consts: &'a mut Vec<Constant<'tcx>>) -> Self {
11 RequiredConstsVisitor { required_consts }
15 impl<'tcx> Visitor<'tcx> for RequiredConstsVisitor<'_, 'tcx> {
16 fn visit_constant(&mut self, constant: &Constant<'tcx>, _: Location) {
17 let literal = constant.literal;
19 ConstantKind::Ty(c) => match c.kind() {
20 ConstKind::Param(_) => {}
21 _ => bug!("only ConstKind::Param should be encountered here, got {:#?}", c),
23 ConstantKind::Unevaluated(..) => self.required_consts.push(*constant),
24 ConstantKind::Val(..) => {}