1 //! the rustc crate store interface. This also includes types that
2 //! are *mostly* used as a part of that interface, but these should
3 //! probably get a better home if someone can find one.
8 use rustc_ast::expand::allocator::AllocatorKind;
9 use rustc_data_structures::svh::Svh;
10 use rustc_data_structures::sync::{self, MetadataRef};
11 use rustc_hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
12 use rustc_hir::definitions::{DefKey, DefPath, DefPathHash, DefPathTable};
13 use rustc_macros::HashStable;
14 use rustc_session::search_paths::PathKind;
15 use rustc_session::utils::NativeLibKind;
16 use rustc_session::CrateDisambiguator;
17 use rustc_span::symbol::Symbol;
19 use rustc_target::spec::Target;
22 use std::path::{Path, PathBuf};
24 // lonely orphan structs and enums looking for a better home
26 /// Where a crate came from on the local filesystem. One of these three options
28 #[derive(PartialEq, Clone, Debug, HashStable, Encodable, Decodable)]
29 pub struct CrateSource {
30 pub dylib: Option<(PathBuf, PathKind)>,
31 pub rlib: Option<(PathBuf, PathKind)>,
32 pub rmeta: Option<(PathBuf, PathKind)>,
36 pub fn paths(&self) -> impl Iterator<Item = &PathBuf> {
37 self.dylib.iter().chain(self.rlib.iter()).chain(self.rmeta.iter()).map(|p| &p.0)
41 #[derive(Encodable, Decodable, Copy, Clone, Ord, PartialOrd, Eq, PartialEq, Debug)]
43 pub enum CrateDepKind {
44 /// A dependency that is only used for its macros.
46 /// A dependency that is always injected into the dependency list and so
47 /// doesn't need to be linked to an rlib, e.g., the injected allocator.
49 /// A dependency that is required by an rlib version of this crate.
50 /// Ordinary `extern crate`s result in `Explicit` dependencies.
55 pub fn macros_only(self) -> bool {
57 CrateDepKind::MacrosOnly => true,
58 CrateDepKind::Implicit | CrateDepKind::Explicit => false,
63 #[derive(PartialEq, Clone, Debug, Encodable, Decodable)]
71 pub fn is_some(&self) -> bool {
72 if let LibSource::Some(_) = *self { true } else { false }
75 pub fn option(&self) -> Option<PathBuf> {
77 LibSource::Some(ref p) => Some(p.clone()),
78 LibSource::MetadataOnly | LibSource::None => None,
83 #[derive(Copy, Debug, PartialEq, Clone, Encodable, Decodable, HashStable)]
84 pub enum LinkagePreference {
89 #[derive(Clone, Debug, Encodable, Decodable, HashStable)]
90 pub struct NativeLib {
91 pub kind: NativeLibKind,
92 pub name: Option<Symbol>,
93 pub cfg: Option<ast::MetaItem>,
94 pub foreign_module: Option<DefId>,
95 pub wasm_import_module: Option<Symbol>,
98 #[derive(Clone, TyEncodable, TyDecodable, HashStable)]
99 pub struct ForeignModule {
100 pub foreign_items: Vec<DefId>,
104 #[derive(Copy, Clone, Debug, HashStable)]
105 pub struct ExternCrate {
106 pub src: ExternCrateSource,
108 /// span of the extern crate that caused this to be loaded
111 /// Number of links to reach the extern;
112 /// used to select the extern with the shortest path
115 /// Crate that depends on this crate
116 pub dependency_of: CrateNum,
120 /// If true, then this crate is the crate named by the extern
121 /// crate referenced above. If false, then this crate is a dep
123 pub fn is_direct(&self) -> bool {
124 self.dependency_of == LOCAL_CRATE
127 pub fn rank(&self) -> impl PartialOrd {
129 // - direct extern crate to indirect
130 // - shorter paths to longer
131 (self.is_direct(), !self.path_len)
135 #[derive(Copy, Clone, Debug, HashStable)]
136 pub enum ExternCrateSource {
137 /// Crate is loaded by `extern crate`.
139 /// def_id of the item in the current crate that caused
140 /// this crate to be loaded; note that there could be multiple
144 /// Crate is implicitly loaded by a path resolving through extern prelude.
148 #[derive(Encodable, Decodable)]
149 pub struct EncodedMetadata {
150 pub raw_data: Vec<u8>,
153 impl EncodedMetadata {
154 pub fn new() -> EncodedMetadata {
155 EncodedMetadata { raw_data: Vec::new() }
159 /// The backend's way to give the crate store access to the metadata in a library.
160 /// Note that it returns the raw metadata bytes stored in the library file, whether
161 /// it is compressed, uncompressed, some weird mix, etc.
162 /// rmeta files are backend independent and not handled here.
164 /// At the time of this writing, there is only one backend and one way to store
165 /// metadata in library -- this trait just serves to decouple rustc_metadata from
166 /// the archive reader, which depends on LLVM.
167 pub trait MetadataLoader {
168 fn get_rlib_metadata(&self, target: &Target, filename: &Path) -> Result<MetadataRef, String>;
169 fn get_dylib_metadata(&self, target: &Target, filename: &Path) -> Result<MetadataRef, String>;
172 pub type MetadataLoaderDyn = dyn MetadataLoader + Sync;
174 /// A store of Rust crates, through which their metadata can be accessed.
176 /// Note that this trait should probably not be expanding today. All new
177 /// functionality should be driven through queries instead!
179 /// If you find a method on this trait named `{name}_untracked` it signifies
180 /// that it's *not* tracked for dependency information throughout compilation
181 /// (it'd break incremental compilation) and should only be called pre-HIR (e.g.
183 pub trait CrateStore {
184 fn as_any(&self) -> &dyn Any;
187 fn def_key(&self, def: DefId) -> DefKey;
188 fn def_path(&self, def: DefId) -> DefPath;
189 fn def_path_hash(&self, def: DefId) -> DefPathHash;
190 fn def_path_table(&self, cnum: CrateNum) -> &DefPathTable;
192 // "queries" used in resolve that aren't tracked for incremental compilation
193 fn crate_name_untracked(&self, cnum: CrateNum) -> Symbol;
194 fn crate_is_private_dep_untracked(&self, cnum: CrateNum) -> bool;
195 fn crate_disambiguator_untracked(&self, cnum: CrateNum) -> CrateDisambiguator;
196 fn crate_hash_untracked(&self, cnum: CrateNum) -> Svh;
198 // This is basically a 1-based range of ints, which is a little
199 // silly - I may fix that.
200 fn crates_untracked(&self) -> Vec<CrateNum>;
203 fn encode_metadata(&self, tcx: TyCtxt<'_>) -> EncodedMetadata;
204 fn metadata_encoding_version(&self) -> &[u8];
205 fn allocator_kind(&self) -> Option<AllocatorKind>;
208 pub type CrateStoreDyn = dyn CrateStore + sync::Sync;
210 // This method is used when generating the command line to pass through to
211 // system linker. The linker expects undefined symbols on the left of the
212 // command line to be defined in libraries on the right, not the other way
213 // around. For more info, see some comments in the add_used_library function
216 // In order to get this left-to-right dependency ordering, we perform a
217 // topological sort of all crates putting the leaves at the right-most
219 pub fn used_crates(tcx: TyCtxt<'_>, prefer: LinkagePreference) -> Vec<(CrateNum, LibSource)> {
225 if tcx.dep_kind(cnum).macros_only() {
228 let source = tcx.used_crate_source(cnum);
229 let path = match prefer {
230 LinkagePreference::RequireDynamic => source.dylib.clone().map(|p| p.0),
231 LinkagePreference::RequireStatic => source.rlib.clone().map(|p| p.0),
233 let path = match path {
234 Some(p) => LibSource::Some(p),
236 if source.rmeta.is_some() {
237 LibSource::MetadataOnly
245 .collect::<Vec<_>>();
246 let mut ordering = tcx.postorder_cnums(LOCAL_CRATE).to_owned();
248 libs.sort_by_cached_key(|&(a, _)| ordering.iter().position(|x| *x == a));