1 // Decoding metadata from a single crate's metadata
3 use cstore::{self, CrateMetadata, MetadataBlob, NativeLibrary, ForeignModule};
6 use rustc_data_structures::sync::{Lrc, ReadGuard};
7 use rustc::hir::map::{DefKey, DefPath, DefPathData, DefPathHash, Definitions};
9 use rustc::middle::cstore::LinkagePreference;
10 use rustc::middle::exported_symbols::{ExportedSymbol, SymbolExportLevel};
11 use rustc::hir::def::{self, Def, CtorKind};
12 use rustc::hir::def_id::{CrateNum, DefId, DefIndex, DefIndexAddressSpace,
13 CRATE_DEF_INDEX, LOCAL_CRATE, LocalDefId};
14 use rustc::hir::map::definitions::DefPathTable;
15 use rustc_data_structures::fingerprint::Fingerprint;
16 use rustc::middle::lang_items;
17 use rustc::mir::{self, interpret};
18 use rustc::mir::interpret::AllocDecodingSession;
19 use rustc::session::Session;
20 use rustc::ty::{self, Ty, TyCtxt};
21 use rustc::ty::codec::TyDecoder;
23 use rustc::util::captures::Captures;
29 use rustc_serialize::{Decodable, Decoder, SpecializedDecoder, opaque};
31 use syntax::ast::{self, Ident};
32 use syntax::source_map;
33 use syntax::symbol::InternedString;
34 use syntax::ext::base::{MacroKind, SyntaxExtension};
35 use syntax::ext::hygiene::Mark;
36 use syntax_pos::{self, Span, BytePos, Pos, DUMMY_SP, NO_EXPANSION};
38 pub struct DecodeContext<'a, 'tcx: 'a> {
39 opaque: opaque::Decoder<'a>,
40 cdata: Option<&'a CrateMetadata>,
41 sess: Option<&'a Session>,
42 tcx: Option<TyCtxt<'a, 'tcx, 'tcx>>,
44 // Cache the last used source_file for translating spans as an optimization.
45 last_source_file_index: usize,
47 lazy_state: LazyState,
49 // Used for decoding interpret::AllocIds in a cached & thread-safe manner.
50 alloc_decoding_session: Option<AllocDecodingSession<'a>>,
53 /// Abstract over the various ways one can create metadata decoders.
54 pub trait Metadata<'a, 'tcx>: Copy {
55 fn raw_bytes(self) -> &'a [u8];
56 fn cdata(self) -> Option<&'a CrateMetadata> { None }
57 fn sess(self) -> Option<&'a Session> { None }
58 fn tcx(self) -> Option<TyCtxt<'a, 'tcx, 'tcx>> { None }
60 fn decoder(self, pos: usize) -> DecodeContext<'a, 'tcx> {
63 opaque: opaque::Decoder::new(self.raw_bytes(), pos),
65 sess: self.sess().or(tcx.map(|tcx| tcx.sess)),
67 last_source_file_index: 0,
68 lazy_state: LazyState::NoNode,
69 alloc_decoding_session: self.cdata().map(|cdata| {
70 cdata.alloc_decoding_state.new_decoding_session()
76 impl<'a, 'tcx> Metadata<'a, 'tcx> for &'a MetadataBlob {
77 fn raw_bytes(self) -> &'a [u8] {
83 impl<'a, 'tcx> Metadata<'a, 'tcx> for (&'a MetadataBlob, &'a Session) {
84 fn raw_bytes(self) -> &'a [u8] {
89 fn sess(self) -> Option<&'a Session> {
96 impl<'a, 'tcx> Metadata<'a, 'tcx> for &'a CrateMetadata {
97 fn raw_bytes(self) -> &'a [u8] {
100 fn cdata(self) -> Option<&'a CrateMetadata> {
105 impl<'a, 'tcx> Metadata<'a, 'tcx> for (&'a CrateMetadata, &'a Session) {
106 fn raw_bytes(self) -> &'a [u8] {
109 fn cdata(self) -> Option<&'a CrateMetadata> {
112 fn sess(self) -> Option<&'a Session> {
117 impl<'a, 'tcx> Metadata<'a, 'tcx> for (&'a CrateMetadata, TyCtxt<'a, 'tcx, 'tcx>) {
118 fn raw_bytes(self) -> &'a [u8] {
121 fn cdata(self) -> Option<&'a CrateMetadata> {
124 fn tcx(self) -> Option<TyCtxt<'a, 'tcx, 'tcx>> {
129 impl<'a, 'tcx: 'a, T: Decodable> Lazy<T> {
130 pub fn decode<M: Metadata<'a, 'tcx>>(self, meta: M) -> T {
131 let mut dcx = meta.decoder(self.position);
132 dcx.lazy_state = LazyState::NodeStart(self.position);
133 T::decode(&mut dcx).unwrap()
137 impl<'a, 'tcx: 'a, T: Decodable> LazySeq<T> {
138 pub fn decode<M: Metadata<'a, 'tcx>>(
141 ) -> impl Iterator<Item = T> + Captures<'tcx> + 'a {
142 let mut dcx = meta.decoder(self.position);
143 dcx.lazy_state = LazyState::NodeStart(self.position);
144 (0..self.len).map(move |_| T::decode(&mut dcx).unwrap())
148 impl<'a, 'tcx> DecodeContext<'a, 'tcx> {
149 pub fn tcx(&self) -> TyCtxt<'a, 'tcx, 'tcx> {
150 self.tcx.expect("missing TyCtxt in DecodeContext")
153 pub fn cdata(&self) -> &'a CrateMetadata {
154 self.cdata.expect("missing CrateMetadata in DecodeContext")
157 fn read_lazy_distance(&mut self, min_size: usize) -> Result<usize, <Self as Decoder>::Error> {
158 let distance = self.read_usize()?;
159 let position = match self.lazy_state {
160 LazyState::NoNode => bug!("read_lazy_distance: outside of a metadata node"),
161 LazyState::NodeStart(start) => {
162 assert!(distance + min_size <= start);
163 start - distance - min_size
165 LazyState::Previous(last_min_end) => last_min_end + distance,
167 self.lazy_state = LazyState::Previous(position + min_size);
172 impl<'a, 'tcx: 'a> TyDecoder<'a, 'tcx> for DecodeContext<'a, 'tcx> {
175 fn tcx(&self) -> TyCtxt<'a, 'tcx, 'tcx> {
176 self.tcx.expect("missing TyCtxt in DecodeContext")
180 fn peek_byte(&self) -> u8 {
181 self.opaque.data[self.opaque.position()]
185 fn position(&self) -> usize {
186 self.opaque.position()
189 fn cached_ty_for_shorthand<F>(&mut self,
192 -> Result<Ty<'tcx>, Self::Error>
193 where F: FnOnce(&mut Self) -> Result<Ty<'tcx>, Self::Error>
195 let tcx = self.tcx();
197 let key = ty::CReaderCacheKey {
198 cnum: self.cdata().cnum,
202 if let Some(&ty) = tcx.rcache.borrow().get(&key) {
206 let ty = or_insert_with(self)?;
207 tcx.rcache.borrow_mut().insert(key, ty);
211 fn with_position<F, R>(&mut self, pos: usize, f: F) -> R
212 where F: FnOnce(&mut Self) -> R
214 let new_opaque = opaque::Decoder::new(self.opaque.data, pos);
215 let old_opaque = mem::replace(&mut self.opaque, new_opaque);
216 let old_state = mem::replace(&mut self.lazy_state, LazyState::NoNode);
218 self.opaque = old_opaque;
219 self.lazy_state = old_state;
223 fn map_encoded_cnum_to_current(&self, cnum: CrateNum) -> CrateNum {
224 if cnum == LOCAL_CRATE {
227 self.cdata().cnum_map[cnum]
232 impl<'a, 'tcx, T> SpecializedDecoder<Lazy<T>> for DecodeContext<'a, 'tcx> {
233 fn specialized_decode(&mut self) -> Result<Lazy<T>, Self::Error> {
234 Ok(Lazy::with_position(self.read_lazy_distance(Lazy::<T>::min_size())?))
238 impl<'a, 'tcx, T> SpecializedDecoder<LazySeq<T>> for DecodeContext<'a, 'tcx> {
239 fn specialized_decode(&mut self) -> Result<LazySeq<T>, Self::Error> {
240 let len = self.read_usize()?;
241 let position = if len == 0 {
244 self.read_lazy_distance(LazySeq::<T>::min_size(len))?
246 Ok(LazySeq::with_position_and_length(position, len))
251 impl<'a, 'tcx> SpecializedDecoder<DefId> for DecodeContext<'a, 'tcx> {
253 fn specialized_decode(&mut self) -> Result<DefId, Self::Error> {
254 let krate = CrateNum::decode(self)?;
255 let index = DefIndex::decode(self)?;
264 impl<'a, 'tcx> SpecializedDecoder<DefIndex> for DecodeContext<'a, 'tcx> {
266 fn specialized_decode(&mut self) -> Result<DefIndex, Self::Error> {
267 Ok(DefIndex::from_raw_u32(self.read_u32()?))
271 impl<'a, 'tcx> SpecializedDecoder<LocalDefId> for DecodeContext<'a, 'tcx> {
273 fn specialized_decode(&mut self) -> Result<LocalDefId, Self::Error> {
274 self.specialized_decode().map(|i| LocalDefId::from_def_id(i))
278 impl<'a, 'tcx> SpecializedDecoder<interpret::AllocId> for DecodeContext<'a, 'tcx> {
279 fn specialized_decode(&mut self) -> Result<interpret::AllocId, Self::Error> {
280 if let Some(alloc_decoding_session) = self.alloc_decoding_session {
281 alloc_decoding_session.decode_alloc_id(self)
283 bug!("Attempting to decode interpret::AllocId without CrateMetadata")
288 impl<'a, 'tcx> SpecializedDecoder<Span> for DecodeContext<'a, 'tcx> {
289 fn specialized_decode(&mut self) -> Result<Span, Self::Error> {
290 let tag = u8::decode(self)?;
292 if tag == TAG_INVALID_SPAN {
296 debug_assert_eq!(tag, TAG_VALID_SPAN);
298 let lo = BytePos::decode(self)?;
299 let len = BytePos::decode(self)?;
302 let sess = if let Some(sess) = self.sess {
305 bug!("Cannot decode Span without Session.")
308 let imported_source_files = self.cdata().imported_source_files(&sess.source_map());
310 // Optimize for the case that most spans within a translated item
311 // originate from the same source_file.
312 let last_source_file = &imported_source_files[self.last_source_file_index];
314 if lo >= last_source_file.original_start_pos &&
315 lo <= last_source_file.original_end_pos {
319 let mut b = imported_source_files.len();
323 if imported_source_files[m].original_start_pos > lo {
330 self.last_source_file_index = a;
331 &imported_source_files[a]
335 // Make sure our binary search above is correct.
336 debug_assert!(lo >= source_file.original_start_pos &&
337 lo <= source_file.original_end_pos);
339 // Make sure we correctly filtered out invalid spans during encoding
340 debug_assert!(hi >= source_file.original_start_pos &&
341 hi <= source_file.original_end_pos);
343 let lo = (lo + source_file.translated_source_file.start_pos)
344 - source_file.original_start_pos;
345 let hi = (hi + source_file.translated_source_file.start_pos)
346 - source_file.original_start_pos;
348 Ok(Span::new(lo, hi, NO_EXPANSION))
352 impl<'a, 'tcx> SpecializedDecoder<Fingerprint> for DecodeContext<'a, 'tcx> {
353 fn specialized_decode(&mut self) -> Result<Fingerprint, Self::Error> {
354 Fingerprint::decode_opaque(&mut self.opaque)
358 impl<'a, 'tcx, T: Decodable> SpecializedDecoder<mir::ClearCrossCrate<T>>
359 for DecodeContext<'a, 'tcx> {
361 fn specialized_decode(&mut self) -> Result<mir::ClearCrossCrate<T>, Self::Error> {
362 Ok(mir::ClearCrossCrate::Clear)
366 implement_ty_decoder!( DecodeContext<'a, 'tcx> );
368 impl<'a, 'tcx> MetadataBlob {
369 pub fn is_compatible(&self) -> bool {
370 self.raw_bytes().starts_with(METADATA_HEADER)
373 pub fn get_rustc_version(&self) -> String {
374 Lazy::with_position(METADATA_HEADER.len() + 4).decode(self)
377 pub fn get_root(&self) -> CrateRoot {
378 let slice = self.raw_bytes();
379 let offset = METADATA_HEADER.len();
380 let pos = (((slice[offset + 0] as u32) << 24) | ((slice[offset + 1] as u32) << 16) |
381 ((slice[offset + 2] as u32) << 8) |
382 ((slice[offset + 3] as u32) << 0)) as usize;
383 Lazy::with_position(pos).decode(self)
386 pub fn list_crate_metadata(&self,
387 out: &mut dyn io::Write) -> io::Result<()> {
388 write!(out, "=External Dependencies=\n")?;
389 let root = self.get_root();
390 for (i, dep) in root.crate_deps
393 write!(out, "{} {}{}\n", i + 1, dep.name, dep.extra_filename)?;
400 impl<'tcx> EntryKind<'tcx> {
401 fn to_def(&self, did: DefId) -> Option<Def> {
403 EntryKind::Const(..) => Def::Const(did),
404 EntryKind::AssociatedConst(..) => Def::AssociatedConst(did),
405 EntryKind::ImmStatic |
406 EntryKind::ForeignImmStatic => Def::Static(did, false),
407 EntryKind::MutStatic |
408 EntryKind::ForeignMutStatic => Def::Static(did, true),
409 EntryKind::Struct(_, _) => Def::Struct(did),
410 EntryKind::Union(_, _) => Def::Union(did),
412 EntryKind::ForeignFn(_) => Def::Fn(did),
413 EntryKind::Method(_) => Def::Method(did),
414 EntryKind::Type => Def::TyAlias(did),
415 EntryKind::Existential => Def::Existential(did),
416 EntryKind::AssociatedType(_) => Def::AssociatedTy(did),
417 EntryKind::AssociatedExistential(_) => Def::AssociatedExistential(did),
418 EntryKind::Mod(_) => Def::Mod(did),
419 EntryKind::Variant(_) => Def::Variant(did),
420 EntryKind::Trait(_) => Def::Trait(did),
421 EntryKind::TraitAlias(_) => Def::TraitAlias(did),
422 EntryKind::Enum(..) => Def::Enum(did),
423 EntryKind::MacroDef(_) => Def::Macro(did, MacroKind::Bang),
424 EntryKind::ForeignType => Def::ForeignTy(did),
426 EntryKind::ForeignMod |
427 EntryKind::GlobalAsm |
430 EntryKind::Generator(_) |
431 EntryKind::Closure(_) => return None,
436 /// Create the "fake" DefPathTable for a given proc macro crate.
438 /// The DefPathTable is as follows:
440 /// CRATE_ROOT (DefIndex 0:0)
441 /// |- GlobalMetaDataKind data (DefIndex 1:0 .. DefIndex 1:N)
442 /// |- proc macro #0 (DefIndex 1:N)
443 /// |- proc macro #1 (DefIndex 1:N+1)
445 crate fn proc_macro_def_path_table(crate_root: &CrateRoot,
446 proc_macros: &[(ast::Name, Lrc<SyntaxExtension>)])
449 let mut definitions = Definitions::new();
451 let name = crate_root.name.as_str();
452 let disambiguator = crate_root.disambiguator;
453 debug!("creating proc macro def path table for {:?}/{:?}", name, disambiguator);
454 let crate_root = definitions.create_root_def(&name, disambiguator);
455 for (index, (name, _)) in proc_macros.iter().enumerate() {
456 let def_index = definitions.create_def_with_parent(
459 DefPathData::MacroDef(name.as_interned_str()),
460 DefIndexAddressSpace::High,
463 debug!("definition for {:?} is {:?}", name, def_index);
464 assert_eq!(def_index, DefIndex::from_proc_macro_index(index));
467 definitions.def_path_table().clone()
470 impl<'a, 'tcx> CrateMetadata {
471 fn is_proc_macro(&self, id: DefIndex) -> bool {
472 self.proc_macros.is_some() && id != CRATE_DEF_INDEX
475 fn maybe_entry(&self, item_id: DefIndex) -> Option<Lazy<Entry<'tcx>>> {
476 assert!(!self.is_proc_macro(item_id));
477 self.root.index.lookup(self.blob.raw_bytes(), item_id)
480 fn entry(&self, item_id: DefIndex) -> Entry<'tcx> {
481 match self.maybe_entry(item_id) {
483 bug!("entry: id not found: {:?} in crate {:?} with number {}",
488 Some(d) => d.decode(self),
492 fn local_def_id(&self, index: DefIndex) -> DefId {
499 pub fn item_name(&self, item_index: DefIndex) -> InternedString {
500 self.def_key(item_index)
504 .expect("no name in item_name")
507 pub fn get_def(&self, index: DefIndex) -> Option<Def> {
508 if !self.is_proc_macro(index) {
509 self.entry(index).kind.to_def(self.local_def_id(index))
511 let kind = self.proc_macros.as_ref().unwrap()[index.to_proc_macro_index()].1.kind();
512 Some(Def::Macro(self.local_def_id(index), kind))
516 pub fn get_span(&self, index: DefIndex, sess: &Session) -> Span {
517 match self.is_proc_macro(index) {
519 false => self.entry(index).span.decode((self, sess)),
523 pub fn get_trait_def(&self, item_id: DefIndex, sess: &Session) -> ty::TraitDef {
524 match self.entry(item_id).kind {
525 EntryKind::Trait(data) => {
526 let data = data.decode((self, sess));
527 ty::TraitDef::new(self.local_def_id(item_id),
532 self.def_path_table.def_path_hash(item_id))
534 EntryKind::TraitAlias(_) => {
535 ty::TraitDef::new(self.local_def_id(item_id),
536 hir::Unsafety::Normal,
540 self.def_path_table.def_path_hash(item_id))
542 _ => bug!("def-index does not refer to trait or trait alias"),
546 fn get_variant(&self,
547 tcx: TyCtxt<'a, 'tcx, 'tcx>,
550 adt_kind: ty::AdtKind)
553 let data = match item.kind {
554 EntryKind::Variant(data) |
555 EntryKind::Struct(data, _) |
556 EntryKind::Union(data, _) => data.decode(self),
560 let def_id = self.local_def_id(data.struct_ctor.unwrap_or(index));
561 let attribute_def_id = self.local_def_id(index);
566 Ident::from_interned_str(self.item_name(index)),
568 item.children.decode(self).map(|index| {
569 let f = self.entry(index);
571 did: self.local_def_id(index),
572 ident: Ident::from_interned_str(self.item_name(index)),
573 vis: f.visibility.decode(self)
582 pub fn get_adt_def(&self,
584 tcx: TyCtxt<'a, 'tcx, 'tcx>)
585 -> &'tcx ty::AdtDef {
586 let item = self.entry(item_id);
587 let did = self.local_def_id(item_id);
589 let (kind, repr) = match item.kind {
590 EntryKind::Enum(repr) => (ty::AdtKind::Enum, repr),
591 EntryKind::Struct(_, repr) => (ty::AdtKind::Struct, repr),
592 EntryKind::Union(_, repr) => (ty::AdtKind::Union, repr),
593 _ => bug!("get_adt_def called on a non-ADT {:?}", did),
596 let variants = if let ty::AdtKind::Enum = kind {
600 self.get_variant(tcx, &self.entry(index), index, kind)
604 std::iter::once(self.get_variant(tcx, &item, item_id, kind)).collect()
607 tcx.alloc_adt_def(did, kind, variants, repr)
610 pub fn get_predicates(&self,
612 tcx: TyCtxt<'a, 'tcx, 'tcx>)
613 -> ty::GenericPredicates<'tcx> {
614 self.entry(item_id).predicates.unwrap().decode((self, tcx))
617 pub fn get_predicates_defined_on(&self,
619 tcx: TyCtxt<'a, 'tcx, 'tcx>)
620 -> ty::GenericPredicates<'tcx> {
621 self.entry(item_id).predicates_defined_on.unwrap().decode((self, tcx))
624 pub fn get_super_predicates(&self,
626 tcx: TyCtxt<'a, 'tcx, 'tcx>)
627 -> ty::GenericPredicates<'tcx> {
628 let super_predicates = match self.entry(item_id).kind {
629 EntryKind::Trait(data) => data.decode(self).super_predicates,
630 EntryKind::TraitAlias(data) => data.decode(self).super_predicates,
631 _ => bug!("def-index does not refer to trait or trait alias"),
634 super_predicates.decode((self, tcx))
637 pub fn get_generics(&self,
641 self.entry(item_id).generics.unwrap().decode((self, sess))
644 pub fn get_type(&self, id: DefIndex, tcx: TyCtxt<'a, 'tcx, 'tcx>) -> Ty<'tcx> {
645 self.entry(id).ty.unwrap().decode((self, tcx))
648 pub fn get_stability(&self, id: DefIndex) -> Option<attr::Stability> {
649 match self.is_proc_macro(id) {
651 false => self.entry(id).stability.map(|stab| stab.decode(self)),
655 pub fn get_deprecation(&self, id: DefIndex) -> Option<attr::Deprecation> {
656 match self.is_proc_macro(id) {
658 false => self.entry(id).deprecation.map(|depr| depr.decode(self)),
662 pub fn get_visibility(&self, id: DefIndex) -> ty::Visibility {
663 match self.is_proc_macro(id) {
664 true => ty::Visibility::Public,
665 false => self.entry(id).visibility.decode(self),
669 fn get_impl_data(&self, id: DefIndex) -> ImplData<'tcx> {
670 match self.entry(id).kind {
671 EntryKind::Impl(data) => data.decode(self),
676 pub fn get_parent_impl(&self, id: DefIndex) -> Option<DefId> {
677 self.get_impl_data(id).parent_impl
680 pub fn get_impl_polarity(&self, id: DefIndex) -> hir::ImplPolarity {
681 self.get_impl_data(id).polarity
684 pub fn get_impl_defaultness(&self, id: DefIndex) -> hir::Defaultness {
685 self.get_impl_data(id).defaultness
688 pub fn get_coerce_unsized_info(&self,
690 -> Option<ty::adjustment::CoerceUnsizedInfo> {
691 self.get_impl_data(id).coerce_unsized_info
694 pub fn get_impl_trait(&self,
696 tcx: TyCtxt<'a, 'tcx, 'tcx>)
697 -> Option<ty::TraitRef<'tcx>> {
698 self.get_impl_data(id).trait_ref.map(|tr| tr.decode((self, tcx)))
701 /// Iterates over all the stability attributes in the given crate.
702 pub fn get_lib_features(&self) -> Vec<(ast::Name, Option<ast::Name>)> {
703 // FIXME: For a proc macro crate, not sure whether we should return the "host"
704 // features or an empty Vec. Both don't cause ICEs.
711 /// Iterates over the language items in the given crate.
712 pub fn get_lang_items(&self) -> Vec<(DefId, usize)> {
713 if self.proc_macros.is_some() {
714 // Proc macro crates do not export any lang-items to the target.
720 .map(|(def_index, index)| (self.local_def_id(def_index), index))
725 /// Iterates over each child of the given item.
726 pub fn each_child_of_item<F>(&self, id: DefIndex, mut callback: F, sess: &Session)
727 where F: FnMut(def::Export)
729 if let Some(ref proc_macros) = self.proc_macros {
730 /* If we are loading as a proc macro, we want to return the view of this crate
731 * as a proc macro crate, not as a Rust crate. See `proc_macro_def_path_table`
732 * for the DefPathTable we are corresponding to.
734 if id == CRATE_DEF_INDEX {
735 for (id, &(name, ref ext)) in proc_macros.iter().enumerate() {
736 let def = Def::Macro(
739 index: DefIndex::from_proc_macro_index(id),
743 let ident = Ident::with_empty_ctxt(name);
744 callback(def::Export {
747 vis: ty::Visibility::Public,
756 let item = match self.maybe_entry(id) {
758 Some(item) => item.decode((self, sess)),
761 // Iterate over all children.
762 let macros_only = self.dep_kind.lock().macros_only();
763 for child_index in item.children.decode((self, sess)) {
769 if let Some(child) = self.maybe_entry(child_index) {
770 let child = child.decode((self, sess));
772 EntryKind::MacroDef(..) => {}
773 _ if macros_only => continue,
777 // Hand off the item to the callback.
779 // FIXME(eddyb) Don't encode these in children.
780 EntryKind::ForeignMod => {
781 for child_index in child.children.decode((self, sess)) {
782 if let Some(def) = self.get_def(child_index) {
783 callback(def::Export {
785 ident: Ident::from_interned_str(self.item_name(child_index)),
786 vis: self.get_visibility(child_index),
787 span: self.entry(child_index).span.decode((self, sess)),
793 EntryKind::Impl(_) => continue,
798 let def_key = self.def_key(child_index);
799 let span = child.span.decode((self, sess));
800 if let (Some(def), Some(name)) =
801 (self.get_def(child_index), def_key.disambiguated_data.data.get_opt_name()) {
802 let ident = Ident::from_interned_str(name);
803 let vis = self.get_visibility(child_index);
804 callback(def::Export { def, ident, vis, span });
805 // For non-re-export structs and variants add their constructors to children.
806 // Re-export lists automatically contain constructors when necessary.
809 if let Some(ctor_def_id) = self.get_struct_ctor_def_id(child_index) {
810 let ctor_kind = self.get_ctor_kind(child_index);
811 let ctor_def = Def::StructCtor(ctor_def_id, ctor_kind);
812 callback(def::Export {
814 vis: self.get_visibility(ctor_def_id.index),
819 Def::Variant(def_id) => {
820 // Braced variants, unlike structs, generate unusable names in
821 // value namespace, they are reserved for possible future use.
822 let ctor_kind = self.get_ctor_kind(child_index);
823 let ctor_def = Def::VariantCtor(def_id, ctor_kind);
824 let vis = self.get_visibility(child_index);
825 callback(def::Export { def: ctor_def, ident, vis, span });
833 if let EntryKind::Mod(data) = item.kind {
834 for exp in data.decode((self, sess)).reexports.decode((self, sess)) {
837 _ if macros_only => continue,
845 pub fn const_is_rvalue_promotable_to_static(&self, id: DefIndex) -> bool {
846 match self.entry(id).kind {
847 EntryKind::AssociatedConst(_, data, _) |
848 EntryKind::Const(data, _) => data.ast_promotable,
853 pub fn is_item_mir_available(&self, id: DefIndex) -> bool {
854 !self.is_proc_macro(id) &&
855 self.maybe_entry(id).and_then(|item| item.decode(self).mir).is_some()
858 pub fn maybe_get_optimized_mir(&self,
859 tcx: TyCtxt<'a, 'tcx, 'tcx>,
861 -> Option<Mir<'tcx>> {
862 match self.is_proc_macro(id) {
864 false => self.entry(id).mir.map(|mir| mir.decode((self, tcx))),
868 pub fn mir_const_qualif(&self, id: DefIndex) -> u8 {
869 match self.entry(id).kind {
870 EntryKind::Const(qualif, _) |
871 EntryKind::AssociatedConst(AssociatedContainer::ImplDefault, qualif, _) |
872 EntryKind::AssociatedConst(AssociatedContainer::ImplFinal, qualif, _) => {
879 pub fn get_associated_item(&self, id: DefIndex) -> ty::AssociatedItem {
880 let item = self.entry(id);
881 let def_key = self.def_key(id);
882 let parent = self.local_def_id(def_key.parent.unwrap());
883 let name = def_key.disambiguated_data.data.get_opt_name().unwrap();
885 let (kind, container, has_self) = match item.kind {
886 EntryKind::AssociatedConst(container, _, _) => {
887 (ty::AssociatedKind::Const, container, false)
889 EntryKind::Method(data) => {
890 let data = data.decode(self);
891 (ty::AssociatedKind::Method, data.container, data.has_self)
893 EntryKind::AssociatedType(container) => {
894 (ty::AssociatedKind::Type, container, false)
896 EntryKind::AssociatedExistential(container) => {
897 (ty::AssociatedKind::Existential, container, false)
899 _ => bug!("cannot get associated-item of `{:?}`", def_key)
903 ident: Ident::from_interned_str(name),
905 vis: item.visibility.decode(self),
906 defaultness: container.defaultness(),
907 def_id: self.local_def_id(id),
908 container: container.with_def_id(parent),
909 method_has_self_argument: has_self
913 pub fn get_item_variances(&self, id: DefIndex) -> Vec<ty::Variance> {
914 self.entry(id).variances.decode(self).collect()
917 pub fn get_ctor_kind(&self, node_id: DefIndex) -> CtorKind {
918 match self.entry(node_id).kind {
919 EntryKind::Struct(data, _) |
920 EntryKind::Union(data, _) |
921 EntryKind::Variant(data) => data.decode(self).ctor_kind,
922 _ => CtorKind::Fictive,
926 pub fn get_struct_ctor_def_id(&self, node_id: DefIndex) -> Option<DefId> {
927 match self.entry(node_id).kind {
928 EntryKind::Struct(data, _) => {
929 data.decode(self).struct_ctor.map(|index| self.local_def_id(index))
935 pub fn get_item_attrs(&self, node_id: DefIndex, sess: &Session) -> Lrc<[ast::Attribute]> {
936 if self.is_proc_macro(node_id) {
940 // The attributes for a tuple struct are attached to the definition, not the ctor;
941 // we assume that someone passing in a tuple struct ctor is actually wanting to
942 // look at the definition
943 let def_key = self.def_key(node_id);
944 let item_id = if def_key.disambiguated_data.data == DefPathData::StructCtor {
945 def_key.parent.unwrap()
950 let item = self.entry(item_id);
951 Lrc::from(self.get_attributes(&item, sess))
954 pub fn get_struct_field_names(&self, id: DefIndex) -> Vec<ast::Name> {
958 .map(|index| self.item_name(index).as_symbol())
962 fn get_attributes(&self, item: &Entry<'tcx>, sess: &Session) -> Vec<ast::Attribute> {
964 .decode((self, sess))
966 // Need new unique IDs: old thread-local IDs won't map to new threads.
967 attr.id = attr::mk_attr_id();
973 // Translate a DefId from the current compilation environment to a DefId
974 // for an external crate.
975 fn reverse_translate_def_id(&self, did: DefId) -> Option<DefId> {
976 for (local, &global) in self.cnum_map.iter_enumerated() {
977 if global == did.krate {
988 pub fn get_inherent_implementations_for_type(&self, id: DefIndex) -> Vec<DefId> {
992 .map(|index| self.local_def_id(index))
996 pub fn get_implementations_for_trait(&self,
997 filter: Option<DefId>,
998 result: &mut Vec<DefId>) {
999 if self.proc_macros.is_some() {
1000 // proc-macro crates export no trait impls.
1004 // Do a reverse lookup beforehand to avoid touching the crate_num
1005 // hash map in the loop below.
1006 let filter = match filter.map(|def_id| self.reverse_translate_def_id(def_id)) {
1007 Some(Some(def_id)) => Some((def_id.krate.as_u32(), def_id.index)),
1008 Some(None) => return,
1012 if let Some(filter) = filter {
1013 if let Some(impls) = self.trait_impls
1015 result.extend(impls.decode(self).map(|idx| self.local_def_id(idx)));
1018 for impls in self.trait_impls.values() {
1019 result.extend(impls.decode(self).map(|idx| self.local_def_id(idx)));
1024 pub fn get_trait_of_item(&self, id: DefIndex) -> Option<DefId> {
1025 let def_key = self.def_key(id);
1026 match def_key.disambiguated_data.data {
1027 DefPathData::TypeNs(..) | DefPathData::ValueNs(..) => (),
1028 // Not an associated item
1031 def_key.parent.and_then(|parent_index| {
1032 match self.entry(parent_index).kind {
1033 EntryKind::Trait(_) |
1034 EntryKind::TraitAlias(_) => Some(self.local_def_id(parent_index)),
1041 pub fn get_native_libraries(&self, sess: &Session) -> Vec<NativeLibrary> {
1042 if self.proc_macros.is_some() {
1043 // Proc macro crates do not have any *target* native libraries.
1046 self.root.native_libraries.decode((self, sess)).collect()
1050 pub fn get_foreign_modules(&self, sess: &Session) -> Vec<ForeignModule> {
1051 if self.proc_macros.is_some() {
1052 // Proc macro crates do not have any *target* foreign modules.
1055 self.root.foreign_modules.decode((self, sess)).collect()
1059 pub fn get_dylib_dependency_formats(&self) -> Vec<(CrateNum, LinkagePreference)> {
1061 .dylib_dependency_formats
1064 .flat_map(|(i, link)| {
1065 let cnum = CrateNum::new(i + 1);
1066 link.map(|link| (self.cnum_map[cnum], link))
1071 pub fn get_missing_lang_items(&self) -> Vec<lang_items::LangItem> {
1072 if self.proc_macros.is_some() {
1073 // Proc macro crates do not depend on any target weak lang-items.
1083 pub fn get_fn_arg_names(&self, id: DefIndex) -> Vec<ast::Name> {
1084 let arg_names = match self.entry(id).kind {
1085 EntryKind::Fn(data) |
1086 EntryKind::ForeignFn(data) => data.decode(self).arg_names,
1087 EntryKind::Method(data) => data.decode(self).fn_data.arg_names,
1088 _ => LazySeq::empty(),
1090 arg_names.decode(self).collect()
1093 pub fn exported_symbols(&self,
1094 tcx: TyCtxt<'a, 'tcx, 'tcx>)
1095 -> Vec<(ExportedSymbol<'tcx>, SymbolExportLevel)> {
1096 if self.proc_macros.is_some() {
1097 // If this crate is a custom derive crate, then we're not even going to
1098 // link those in so we skip those crates.
1101 let lazy_seq: LazySeq<(ExportedSymbol<'tcx>, SymbolExportLevel)> =
1102 LazySeq::with_position_and_length(self.root.exported_symbols.position,
1103 self.root.exported_symbols.len);
1104 lazy_seq.decode((self, tcx)).collect()
1108 pub fn get_rendered_const(&self, id: DefIndex) -> String {
1109 match self.entry(id).kind {
1110 EntryKind::Const(_, data) |
1111 EntryKind::AssociatedConst(_, _, data) => data.decode(self).0,
1116 pub fn get_macro(&self, id: DefIndex) -> MacroDef {
1117 let entry = self.entry(id);
1119 EntryKind::MacroDef(macro_def) => macro_def.decode(self),
1124 crate fn is_const_fn_raw(&self, id: DefIndex) -> bool {
1125 let constness = match self.entry(id).kind {
1126 EntryKind::Method(data) => data.decode(self).fn_data.constness,
1127 EntryKind::Fn(data) => data.decode(self).constness,
1128 _ => hir::Constness::NotConst,
1130 constness == hir::Constness::Const
1133 pub fn is_foreign_item(&self, id: DefIndex) -> bool {
1134 match self.entry(id).kind {
1135 EntryKind::ForeignImmStatic |
1136 EntryKind::ForeignMutStatic |
1137 EntryKind::ForeignFn(_) => true,
1142 pub fn fn_sig(&self,
1144 tcx: TyCtxt<'a, 'tcx, 'tcx>)
1145 -> ty::PolyFnSig<'tcx> {
1146 let sig = match self.entry(id).kind {
1147 EntryKind::Fn(data) |
1148 EntryKind::ForeignFn(data) => data.decode(self).sig,
1149 EntryKind::Method(data) => data.decode(self).fn_data.sig,
1150 EntryKind::Variant(data) |
1151 EntryKind::Struct(data, _) => data.decode(self).ctor_sig.unwrap(),
1152 EntryKind::Closure(data) => data.decode(self).sig,
1155 sig.decode((self, tcx))
1159 pub fn def_key(&self, index: DefIndex) -> DefKey {
1160 self.def_path_table.def_key(index)
1163 // Returns the path leading to the thing with this `id`.
1164 pub fn def_path(&self, id: DefIndex) -> DefPath {
1165 debug!("def_path(cnum={:?}, id={:?})", self.cnum, id);
1166 DefPath::make(self.cnum, id, |parent| self.def_path_table.def_key(parent))
1170 pub fn def_path_hash(&self, index: DefIndex) -> DefPathHash {
1171 self.def_path_table.def_path_hash(index)
1174 /// Imports the source_map from an external crate into the source_map of the crate
1175 /// currently being compiled (the "local crate").
1177 /// The import algorithm works analogous to how AST items are inlined from an
1178 /// external crate's metadata:
1179 /// For every SourceFile in the external source_map an 'inline' copy is created in the
1180 /// local source_map. The correspondence relation between external and local
1181 /// SourceFiles is recorded in the `ImportedSourceFile` objects returned from this
1182 /// function. When an item from an external crate is later inlined into this
1183 /// crate, this correspondence information is used to translate the span
1184 /// information of the inlined item so that it refers the correct positions in
1185 /// the local source_map (see `<decoder::DecodeContext as SpecializedDecoder<Span>>`).
1187 /// The import algorithm in the function below will reuse SourceFiles already
1188 /// existing in the local source_map. For example, even if the SourceFile of some
1189 /// source file of libstd gets imported many times, there will only ever be
1190 /// one SourceFile object for the corresponding file in the local source_map.
1192 /// Note that imported SourceFiles do not actually contain the source code of the
1193 /// file they represent, just information about length, line breaks, and
1194 /// multibyte characters. This information is enough to generate valid debuginfo
1195 /// for items inlined from other crates.
1197 /// Proc macro crates don't currently export spans, so this function does not have
1198 /// to work for them.
1199 pub fn imported_source_files(&'a self,
1200 local_source_map: &source_map::SourceMap)
1201 -> ReadGuard<'a, Vec<cstore::ImportedSourceFile>> {
1203 let source_files = self.source_map_import_info.borrow();
1204 if !source_files.is_empty() {
1205 return source_files;
1209 // Lock the source_map_import_info to ensure this only happens once
1210 let mut source_map_import_info = self.source_map_import_info.borrow_mut();
1212 if !source_map_import_info.is_empty() {
1213 drop(source_map_import_info);
1214 return self.source_map_import_info.borrow();
1217 let external_source_map = self.root.source_map.decode(self);
1219 let imported_source_files = external_source_map.map(|source_file_to_import| {
1220 // We can't reuse an existing SourceFile, so allocate a new one
1221 // containing the information we need.
1222 let syntax_pos::SourceFile { name,
1228 mut multibyte_chars,
1229 mut non_narrow_chars,
1231 .. } = source_file_to_import;
1233 let source_length = (end_pos - start_pos).to_usize();
1235 // Translate line-start positions and multibyte character
1236 // position into frame of reference local to file.
1237 // `SourceMap::new_imported_source_file()` will then translate those
1238 // coordinates to their new global frame of reference when the
1239 // offset of the SourceFile is known.
1240 for pos in &mut lines {
1241 *pos = *pos - start_pos;
1243 for mbc in &mut multibyte_chars {
1244 mbc.pos = mbc.pos - start_pos;
1246 for swc in &mut non_narrow_chars {
1247 *swc = *swc - start_pos;
1250 let local_version = local_source_map.new_imported_source_file(name,
1259 debug!("CrateMetaData::imported_source_files alloc \
1260 source_file {:?} original (start_pos {:?} end_pos {:?}) \
1261 translated (start_pos {:?} end_pos {:?})",
1262 local_version.name, start_pos, end_pos,
1263 local_version.start_pos, local_version.end_pos);
1265 cstore::ImportedSourceFile {
1266 original_start_pos: start_pos,
1267 original_end_pos: end_pos,
1268 translated_source_file: local_version,
1272 *source_map_import_info = imported_source_files;
1273 drop(source_map_import_info);
1275 // This shouldn't borrow twice, but there is no way to downgrade RefMut to Ref.
1276 self.source_map_import_info.borrow()