rapx/analysis/safety_flow/
hir_visitor.rs

1use crate::compat::FxHashMap;
2use rustc_hir::{
3    Block, BlockCheckMode, Body, BodyId, ExprKind, ImplItemKind, QPath, def_id::DefId, intravisit,
4    intravisit::Visitor,
5};
6use rustc_middle::ty::{self, Ty, TyCtxt};
7use std::collections::HashSet;
8
9pub struct ContainsUnsafe<'tcx> {
10    tcx: TyCtxt<'tcx>,
11    fn_unsafe: bool,
12    block_unsafe: bool,
13}
14
15impl<'tcx> ContainsUnsafe<'tcx> {
16    pub fn contains_unsafe(tcx: TyCtxt<'tcx>, body_id: BodyId) -> (bool, bool) {
17        let mut visitor = ContainsUnsafe {
18            tcx,
19            fn_unsafe: false,
20            block_unsafe: false,
21        };
22
23        let body = visitor.tcx.hir_body(body_id);
24        visitor.fn_unsafety(body);
25        visitor.visit_body(body);
26
27        (visitor.fn_unsafe, visitor.block_unsafe)
28    }
29
30    /*
31     * Check if the body corresponds to a function;
32     * If yes, check the function safety declaration based on its signature.
33     */
34    fn fn_unsafety(&mut self, body: &'tcx Body<'tcx>) {
35        let did = body.value.hir_id.owner.to_def_id();
36        if self.tcx.def_kind(did) == rustc_hir::def::DefKind::Fn
37            || self.tcx.def_kind(did) == rustc_hir::def::DefKind::AssocFn
38        {
39            let sig = self.tcx.fn_sig(did);
40            if let rustc_hir::Safety::Unsafe = sig.skip_binder().safety() {
41                self.fn_unsafe = true;
42            }
43        }
44    }
45}
46
47/*
48 * Check if each block contains unsafe marker.
49 */
50impl<'tcx> Visitor<'tcx> for ContainsUnsafe<'tcx> {
51    fn visit_block(&mut self, block: &'tcx Block<'tcx>) {
52        if let BlockCheckMode::UnsafeBlock(_unsafe_source) = block.rules {
53            self.block_unsafe = true;
54        }
55        intravisit::walk_block(self, block);
56    }
57}
58
59pub struct ContainsLit {
60    pub structs_used: HashSet<String>,
61}
62
63impl<'tcx> Visitor<'tcx> for ContainsLit {
64    fn visit_expr(&mut self, expr: &'tcx rustc_hir::Expr<'tcx>) {
65        if let ExprKind::Struct(ref qpath, _, _) = expr.kind {
66            if let QPath::Resolved(_, path) = qpath {
67                if let Some(ident) = path.segments.last().map(|segment| segment.ident) {
68                    self.structs_used.insert(ident.to_string());
69                }
70            }
71        }
72        intravisit::walk_expr(self, expr);
73    }
74}
75
76/// (`DefId` of ADT) => Vec<(HirId of relevant impl block, impl_self_ty)>
77/// We use this map to quickly access associated impl blocks per ADT.
78/// `impl_self_ty` in the return value may differ from `tcx.type_of(ADT.DefID)`,
79/// as different instantiations of the same ADT are distinct `Ty`s.
80/// (e.g. Foo<i32, i64>, Foo<String, i32>)
81pub type AdtImplMap<'tcx> = FxHashMap<DefId, Vec<(DefId, Ty<'tcx>)>>;
82
83/// Create & initialize `AdtImplMap`.
84/// `AdtImplMap` is initialized before analysis of each crate,
85/// avoiding quadratic complexity of scanning all impl blocks for each ADT.
86pub fn create_adt_impl_map(tcx: TyCtxt<'_>) -> AdtImplMap<'_> {
87    let mut map = FxHashMap::default();
88    for impl_item_id in tcx.hir_crate_items(()).impl_items() {
89        let impl_item = tcx.hir_impl_item(impl_item_id);
90        if let ImplItemKind::Type(ty) = impl_item.kind {
91            let impl_self_ty = tcx.type_of(ty.hir_id.owner).skip_binder();
92            if let ty::Adt(impl_self_adt_def, _impl_substs) = impl_self_ty.kind() {
93                map.entry(impl_self_adt_def.did())
94                    .or_insert_with(Vec::new)
95                    .push((impl_item_id.owner_id.to_def_id(), impl_self_ty));
96            }
97        }
98    }
99    map
100}
rapx/analysis/safety_flow/hir_visitor.rs

rapx/analysis/safety_flow/
hir_visitor.rs
