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.
5 use crate::hir::map as hir_map;
6 use crate::hir::map::definitions::{DefKey, DefPathTable};
7 use crate::session::search_paths::PathKind;
8 use crate::session::CrateDisambiguator;
11 use rustc_data_structures::svh::Svh;
12 use rustc_data_structures::sync::{self, MetadataRef};
13 use rustc_hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
14 use rustc_macros::HashStable;
15 use rustc_span::symbol::Symbol;
17 use rustc_target::spec::Target;
19 use std::path::{Path, PathBuf};
21 use syntax::expand::allocator::AllocatorKind;
23 pub use self::NativeLibraryKind::*;
24 pub use rustc_session::utils::NativeLibraryKind;
26 // lonely orphan structs and enums looking for a better home
28 /// Where a crate came from on the local filesystem. One of these three options
30 #[derive(PartialEq, Clone, Debug, HashStable, RustcEncodable, RustcDecodable)]
31 pub struct CrateSource {
32 pub dylib: Option<(PathBuf, PathKind)>,
33 pub rlib: Option<(PathBuf, PathKind)>,
34 pub rmeta: Option<(PathBuf, PathKind)>,
38 pub fn paths(&self) -> impl Iterator<Item = &PathBuf> {
39 self.dylib.iter().chain(self.rlib.iter()).chain(self.rmeta.iter()).map(|p| &p.0)
56 /// A dependency that is only used for its macros, none of which are visible from other crates.
57 /// These are included in the metadata only as placeholders and are ignored when decoding.
59 /// A dependency that is only used for its macros.
61 /// A dependency that is always injected into the dependency list and so
62 /// doesn't need to be linked to an rlib, e.g., the injected allocator.
64 /// A dependency that is required by an rlib version of this crate.
65 /// Ordinary `extern crate`s result in `Explicit` dependencies.
70 pub fn macros_only(self) -> bool {
72 DepKind::UnexportedMacrosOnly | DepKind::MacrosOnly => true,
73 DepKind::Implicit | DepKind::Explicit => false,
78 #[derive(PartialEq, Clone, Debug, RustcEncodable, RustcDecodable)]
86 pub fn is_some(&self) -> bool {
87 if let LibSource::Some(_) = *self { true } else { false }
90 pub fn option(&self) -> Option<PathBuf> {
92 LibSource::Some(ref p) => Some(p.clone()),
93 LibSource::MetadataOnly | LibSource::None => None,
98 #[derive(Copy, Debug, PartialEq, Clone, RustcEncodable, RustcDecodable, HashStable)]
99 pub enum LinkagePreference {
104 #[derive(Clone, Debug, RustcEncodable, RustcDecodable, HashStable)]
105 pub struct NativeLibrary {
106 pub kind: NativeLibraryKind,
107 pub name: Option<Symbol>,
108 pub cfg: Option<ast::MetaItem>,
109 pub foreign_module: Option<DefId>,
110 pub wasm_import_module: Option<Symbol>,
113 #[derive(Clone, RustcEncodable, RustcDecodable, HashStable)]
114 pub struct ForeignModule {
115 pub foreign_items: Vec<DefId>,
119 #[derive(Copy, Clone, Debug, HashStable)]
120 pub struct ExternCrate {
121 pub src: ExternCrateSource,
123 /// span of the extern crate that caused this to be loaded
126 /// Number of links to reach the extern;
127 /// used to select the extern with the shortest path
130 /// Crate that depends on this crate
131 pub dependency_of: CrateNum,
135 /// If true, then this crate is the crate named by the extern
136 /// crate referenced above. If false, then this crate is a dep
138 pub fn is_direct(&self) -> bool {
139 self.dependency_of == LOCAL_CRATE
142 pub fn rank(&self) -> impl PartialOrd {
144 // - direct extern crate to indirect
145 // - shorter paths to longer
146 (self.is_direct(), !self.path_len)
150 #[derive(Copy, Clone, Debug, HashStable)]
151 pub enum ExternCrateSource {
152 /// Crate is loaded by `extern crate`.
154 /// def_id of the item in the current crate that caused
155 /// this crate to be loaded; note that there could be multiple
159 /// Crate is implicitly loaded by a path resolving through extern prelude.
163 #[derive(RustcEncodable, RustcDecodable)]
164 pub struct EncodedMetadata {
165 pub raw_data: Vec<u8>,
168 impl EncodedMetadata {
169 pub fn new() -> EncodedMetadata {
170 EncodedMetadata { raw_data: Vec::new() }
174 /// The backend's way to give the crate store access to the metadata in a library.
175 /// Note that it returns the raw metadata bytes stored in the library file, whether
176 /// it is compressed, uncompressed, some weird mix, etc.
177 /// rmeta files are backend independent and not handled here.
179 /// At the time of this writing, there is only one backend and one way to store
180 /// metadata in library -- this trait just serves to decouple rustc_metadata from
181 /// the archive reader, which depends on LLVM.
182 pub trait MetadataLoader {
183 fn get_rlib_metadata(&self, target: &Target, filename: &Path) -> Result<MetadataRef, String>;
184 fn get_dylib_metadata(&self, target: &Target, filename: &Path) -> Result<MetadataRef, String>;
187 pub type MetadataLoaderDyn = dyn MetadataLoader + Sync;
189 /// A store of Rust crates, through which their metadata can be accessed.
191 /// Note that this trait should probably not be expanding today. All new
192 /// functionality should be driven through queries instead!
194 /// If you find a method on this trait named `{name}_untracked` it signifies
195 /// that it's *not* tracked for dependency information throughout compilation
196 /// (it'd break incremental compilation) and should only be called pre-HIR (e.g.
198 pub trait CrateStore {
199 fn as_any(&self) -> &dyn Any;
202 fn def_key(&self, def: DefId) -> DefKey;
203 fn def_path(&self, def: DefId) -> hir_map::DefPath;
204 fn def_path_hash(&self, def: DefId) -> hir_map::DefPathHash;
205 fn def_path_table(&self, cnum: CrateNum) -> &DefPathTable;
207 // "queries" used in resolve that aren't tracked for incremental compilation
208 fn crate_name_untracked(&self, cnum: CrateNum) -> Symbol;
209 fn crate_is_private_dep_untracked(&self, cnum: CrateNum) -> bool;
210 fn crate_disambiguator_untracked(&self, cnum: CrateNum) -> CrateDisambiguator;
211 fn crate_hash_untracked(&self, cnum: CrateNum) -> Svh;
213 // This is basically a 1-based range of ints, which is a little
214 // silly - I may fix that.
215 fn crates_untracked(&self) -> Vec<CrateNum>;
218 fn encode_metadata(&self, tcx: TyCtxt<'_>) -> EncodedMetadata;
219 fn metadata_encoding_version(&self) -> &[u8];
220 fn allocator_kind(&self) -> Option<AllocatorKind>;
223 pub type CrateStoreDyn = dyn CrateStore + sync::Sync;
225 // This method is used when generating the command line to pass through to
226 // system linker. The linker expects undefined symbols on the left of the
227 // command line to be defined in libraries on the right, not the other way
228 // around. For more info, see some comments in the add_used_library function
231 // In order to get this left-to-right dependency ordering, we perform a
232 // topological sort of all crates putting the leaves at the right-most
234 pub fn used_crates(tcx: TyCtxt<'_>, prefer: LinkagePreference) -> Vec<(CrateNum, LibSource)> {
240 if tcx.dep_kind(cnum).macros_only() {
243 let source = tcx.used_crate_source(cnum);
244 let path = match prefer {
245 LinkagePreference::RequireDynamic => source.dylib.clone().map(|p| p.0),
246 LinkagePreference::RequireStatic => source.rlib.clone().map(|p| p.0),
248 let path = match path {
249 Some(p) => LibSource::Some(p),
251 if source.rmeta.is_some() {
252 LibSource::MetadataOnly
260 .collect::<Vec<_>>();
261 let mut ordering = tcx.postorder_cnums(LOCAL_CRATE).to_owned();
263 libs.sort_by_cached_key(|&(a, _)| ordering.iter().position(|x| *x == a));