1 // Copyright 2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 use hir::def_id::CrateNum;
15 macro_rules! try_opt {
24 #[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, RustcEncodable, RustcDecodable)]
25 pub enum DepNode<D: Clone + Debug> {
26 // The `D` type is "how definitions are identified".
27 // During compilation, it is always `DefId`, but when serializing
28 // it is mapped to `DefPath`.
30 // Represents the `Krate` as a whole (the `hir::Krate` value) (as
31 // distinct from the krate module). This is basically a hash of
32 // the entire krate, so if you read from `Krate` (e.g., by calling
33 // `tcx.hir.krate()`), we will have to assume that any change
34 // means that you need to be recompiled. This is because the
35 // `Krate` value gives you access to all other items. To avoid
36 // this fate, do not call `tcx.hir.krate()`; instead, prefer
37 // wrappers like `tcx.visit_all_items_in_krate()`. If there is no
38 // suitable wrapper, you can use `tcx.dep_graph.ignore()` to gain
39 // access to the krate, but you must remember to add suitable
40 // edges yourself for the individual items that you read.
43 // Represents the HIR node with the given node-id
46 // Represents the body of a function or method. The def-id is that of the
50 // Represents the metadata for a given HIR node, typically found
51 // in an extern crate.
54 // Represents some piece of metadata global to its crate.
55 GlobalMetaData(D, GlobalMetaDataKind),
57 // Represents some artifact that we save to disk. Note that these
58 // do not have a def-id as part of their identifier.
59 WorkProduct(Arc<WorkProductId>),
61 // Represents different phases in the compiler.
65 CoherenceCheckTrait(D),
66 CoherenceCheckImpl(D),
67 CoherenceOverlapCheck(D),
68 CoherenceOverlapCheckSpecial(D),
70 PrivacyAccessLevels(CrateNum),
72 // Represents the MIR for a fn; also used as the task node for
73 // things read/modify that MIR.
88 // Nodes representing bits of computed IR in the tcx. Each shared
89 // table in the tcx (or elsewhere) maps to one of these
90 // nodes. Often we map multiple tables to the same node if there
91 // is no point in distinguishing them (e.g., both the type and
92 // predicates for an item wind up in `ItemSignature`).
95 ItemVarianceConstraints(D),
98 TypeParamPredicates((D, D)),
102 AssociatedItemDefIds(D),
109 SpecializationGraph(D),
112 // The set of impls for a given trait. Ultimately, it would be
113 // nice to get more fine-grained here (e.g., to include a
114 // simplified type), but we can't do that until we restructure the
115 // HIR to distinguish the *header* of an impl from its body. This
116 // is because changes to the header may change the self-type of
117 // the impl and hence would require us to be more conservative
118 // than changes in the impl body.
123 // Nodes representing caches. To properly handle a true cache, we
124 // don't use a DepTrackingMap, but rather we push a task node.
125 // Otherwise the write into the map would be incorrectly
126 // attributed to the first task that happened to fill the cache,
127 // which would yield an overly conservative dep-graph.
131 // Trait selection cache is a little funny. Given a trait
132 // reference like `Foo: SomeTrait<Bar>`, there could be
133 // arbitrarily many def-ids to map on in there (e.g., `Foo`,
134 // `SomeTrait`, `Bar`). We could have a vector of them, but it
135 // requires heap-allocation, and trait sel in general can be a
136 // surprisingly hot path. So instead we pick two def-ids: the
137 // trait def-id, and the first def-id in the input types. If there
138 // is no def-id in the input types, then we use the trait def-id
139 // again. So for example:
141 // - `i32: Clone` -> `TraitSelect { trait_def_id: Clone, self_def_id: Clone }`
142 // - `u32: Clone` -> `TraitSelect { trait_def_id: Clone, self_def_id: Clone }`
143 // - `Clone: Clone` -> `TraitSelect { trait_def_id: Clone, self_def_id: Clone }`
144 // - `Vec<i32>: Clone` -> `TraitSelect { trait_def_id: Clone, self_def_id: Vec }`
145 // - `String: Clone` -> `TraitSelect { trait_def_id: Clone, self_def_id: String }`
146 // - `Foo: Trait<Bar>` -> `TraitSelect { trait_def_id: Trait, self_def_id: Foo }`
147 // - `Foo: Trait<i32>` -> `TraitSelect { trait_def_id: Trait, self_def_id: Foo }`
148 // - `(Foo, Bar): Trait` -> `TraitSelect { trait_def_id: Trait, self_def_id: Foo }`
149 // - `i32: Trait<Foo>` -> `TraitSelect { trait_def_id: Trait, self_def_id: Foo }`
151 // You can see that we map many trait refs to the same
152 // trait-select node. This is not a problem, it just means
153 // imprecision in our dep-graph tracking. The important thing is
154 // that for any given trait-ref, we always map to the **same**
155 // trait-select node.
156 TraitSelect { trait_def_id: D, input_def_id: D },
158 // For proj. cache, we just keep a list of all def-ids, since it is
160 ProjectionCache { def_ids: Vec<D> },
166 ItemBodyNestedBodies(D),
167 ConstIsRvaluePromotableToStatic(D),
174 FileMap(D, Arc<String>),
177 impl<D: Clone + Debug> DepNode<D> {
179 pub fn from_label_string(label: &str, data: D) -> Result<DepNode<D>, ()> {
181 ($($name:ident,)*) => {
183 $(stringify!($name) => Ok(DepNode::$name(data)),)*
189 if label == "Krate" {
191 return Ok(DepNode::Krate);
203 AssociatedItemDefIds,
212 pub fn map_def<E, OP>(&self, mut op: OP) -> Option<DepNode<E>>
213 where OP: FnMut(&D) -> Option<E>, E: Clone + Debug
215 use self::DepNode::*;
218 Krate => Some(Krate),
219 BorrowCheckKrate => Some(BorrowCheckKrate),
220 MirKrate => Some(MirKrate),
221 TypeckBodiesKrate => Some(TypeckBodiesKrate),
222 Coherence => Some(Coherence),
223 CrateVariances => Some(CrateVariances),
224 Resolve => Some(Resolve),
225 Variance => Some(Variance),
226 PrivacyAccessLevels(k) => Some(PrivacyAccessLevels(k)),
227 Reachability => Some(Reachability),
228 MirKeys => Some(MirKeys),
229 LateLintCheck => Some(LateLintCheck),
230 TransWriteMetadata => Some(TransWriteMetadata),
232 // work product names do not need to be mapped, because
233 // they are always absolute.
234 WorkProduct(ref id) => Some(WorkProduct(id.clone())),
236 Hir(ref d) => op(d).map(Hir),
237 HirBody(ref d) => op(d).map(HirBody),
238 MetaData(ref d) => op(d).map(MetaData),
239 CoherenceCheckTrait(ref d) => op(d).map(CoherenceCheckTrait),
240 CoherenceCheckImpl(ref d) => op(d).map(CoherenceCheckImpl),
241 CoherenceOverlapCheck(ref d) => op(d).map(CoherenceOverlapCheck),
242 CoherenceOverlapCheckSpecial(ref d) => op(d).map(CoherenceOverlapCheckSpecial),
243 Mir(ref d) => op(d).map(Mir),
244 MirShim(ref def_ids) => {
245 let def_ids: Option<Vec<E>> = def_ids.iter().map(op).collect();
248 BorrowCheck(ref d) => op(d).map(BorrowCheck),
249 RegionMaps(ref d) => op(d).map(RegionMaps),
250 RvalueCheck(ref d) => op(d).map(RvalueCheck),
251 TransCrateItem(ref d) => op(d).map(TransCrateItem),
252 AssociatedItems(ref d) => op(d).map(AssociatedItems),
253 ItemSignature(ref d) => op(d).map(ItemSignature),
254 ItemVariances(ref d) => op(d).map(ItemVariances),
255 ItemVarianceConstraints(ref d) => op(d).map(ItemVarianceConstraints),
256 IsForeignItem(ref d) => op(d).map(IsForeignItem),
257 TypeParamPredicates((ref item, ref param)) => {
258 Some(TypeParamPredicates((try_opt!(op(item)), try_opt!(op(param)))))
260 SizedConstraint(ref d) => op(d).map(SizedConstraint),
261 DtorckConstraint(ref d) => op(d).map(DtorckConstraint),
262 AdtDestructor(ref d) => op(d).map(AdtDestructor),
263 AssociatedItemDefIds(ref d) => op(d).map(AssociatedItemDefIds),
264 InherentImpls(ref d) => op(d).map(InherentImpls),
265 TypeckTables(ref d) => op(d).map(TypeckTables),
266 UsedTraitImports(ref d) => op(d).map(UsedTraitImports),
267 ConstEval(ref d) => op(d).map(ConstEval),
268 SymbolName(ref d) => op(d).map(SymbolName),
269 SpecializationGraph(ref d) => op(d).map(SpecializationGraph),
270 ObjectSafety(ref d) => op(d).map(ObjectSafety),
271 TraitImpls(ref d) => op(d).map(TraitImpls),
272 AllLocalTraitImpls => Some(AllLocalTraitImpls),
273 TraitItems(ref d) => op(d).map(TraitItems),
274 ReprHints(ref d) => op(d).map(ReprHints),
275 TraitSelect { ref trait_def_id, ref input_def_id } => {
276 op(trait_def_id).and_then(|trait_def_id| {
277 op(input_def_id).and_then(|input_def_id| {
278 Some(TraitSelect { trait_def_id: trait_def_id,
279 input_def_id: input_def_id })
283 ProjectionCache { ref def_ids } => {
284 let def_ids: Option<Vec<E>> = def_ids.iter().map(op).collect();
285 def_ids.map(|d| ProjectionCache { def_ids: d })
287 DescribeDef(ref d) => op(d).map(DescribeDef),
288 DefSpan(ref d) => op(d).map(DefSpan),
289 Stability(ref d) => op(d).map(Stability),
290 Deprecation(ref d) => op(d).map(Deprecation),
291 ItemAttrs(ref d) => op(d).map(ItemAttrs),
292 FnArgNames(ref d) => op(d).map(FnArgNames),
293 ImplParent(ref d) => op(d).map(ImplParent),
294 TraitOfItem(ref d) => op(d).map(TraitOfItem),
295 IsExportedSymbol(ref d) => op(d).map(IsExportedSymbol),
296 ItemBodyNestedBodies(ref d) => op(d).map(ItemBodyNestedBodies),
297 ConstIsRvaluePromotableToStatic(ref d) => op(d).map(ConstIsRvaluePromotableToStatic),
298 IsMirAvailable(ref d) => op(d).map(IsMirAvailable),
299 GlobalMetaData(ref d, kind) => op(d).map(|d| GlobalMetaData(d, kind)),
300 FileMap(ref d, ref file_name) => op(d).map(|d| FileMap(d, file_name.clone())),
305 /// A "work product" corresponds to a `.o` (or other) file that we
306 /// save in between runs. These ids do not have a DefId but rather
307 /// some independent path or string that persists between runs without
308 /// the need to be mapped or unmapped. (This ensures we can serialize
309 /// them even in the absence of a tcx.)
310 #[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, RustcEncodable, RustcDecodable)]
311 pub struct WorkProductId(pub String);
313 #[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, RustcEncodable, RustcDecodable)]
314 pub enum GlobalMetaDataKind {
317 DylibDependencyFormats,