1 // Decoding metadata from a single crate's metadata
3 use crate::creader::{CStore, CrateMetadataRef};
8 use rustc_data_structures::captures::Captures;
9 use rustc_data_structures::fx::FxHashMap;
10 use rustc_data_structures::svh::Svh;
11 use rustc_data_structures::sync::{Lock, LockGuard, Lrc, OnceCell};
12 use rustc_data_structures::unhash::UnhashMap;
13 use rustc_expand::base::{SyntaxExtension, SyntaxExtensionKind};
14 use rustc_expand::proc_macro::{AttrProcMacro, BangProcMacro, DeriveProcMacro};
15 use rustc_hir::def::{CtorKind, CtorOf, DefKind, Res};
16 use rustc_hir::def_id::{CrateNum, DefId, DefIndex, CRATE_DEF_INDEX, LOCAL_CRATE};
17 use rustc_hir::definitions::{DefKey, DefPath, DefPathData, DefPathHash};
18 use rustc_hir::diagnostic_items::DiagnosticItems;
19 use rustc_hir::lang_items;
20 use rustc_index::vec::{Idx, IndexVec};
21 use rustc_middle::metadata::ModChild;
22 use rustc_middle::middle::exported_symbols::{ExportedSymbol, SymbolExportInfo};
23 use rustc_middle::mir::interpret::{AllocDecodingSession, AllocDecodingState};
24 use rustc_middle::ty::codec::TyDecoder;
25 use rustc_middle::ty::fast_reject::SimplifiedType;
26 use rustc_middle::ty::GeneratorDiagnosticData;
27 use rustc_middle::ty::{self, ParameterizedOverTcx, Ty, TyCtxt, Visibility};
28 use rustc_serialize::opaque::MemDecoder;
29 use rustc_serialize::{Decodable, Decoder};
30 use rustc_session::cstore::{
31 CrateSource, ExternCrate, ForeignModule, LinkagePreference, NativeLib,
33 use rustc_session::Session;
34 use rustc_span::hygiene::{ExpnIndex, MacroKind};
35 use rustc_span::source_map::{respan, Spanned};
36 use rustc_span::symbol::{sym, Ident, Symbol};
37 use rustc_span::{self, BytePos, ExpnId, Pos, Span, SyntaxContext, DUMMY_SP};
39 use proc_macro::bridge::client::ProcMacro;
41 use std::iter::TrustedLen;
43 use std::num::NonZeroUsize;
44 use std::path::PathBuf;
47 pub(super) use cstore_impl::provide;
48 pub use cstore_impl::provide_extern;
49 use rustc_span::hygiene::HygieneDecodeContext;
53 /// A reference to the raw binary version of crate metadata.
54 /// A `MetadataBlob` internally is just a reference counted pointer to
55 /// the actual data, so cloning it is cheap.
57 pub(crate) struct MetadataBlob(Lrc<MetadataRef>);
59 // This is needed so we can create an OwningRef into the blob.
60 // The data behind a `MetadataBlob` has a stable address because it is
61 // contained within an Rc/Arc.
62 unsafe impl rustc_data_structures::owning_ref::StableAddress for MetadataBlob {}
64 // This is needed so we can create an OwningRef into the blob.
65 impl std::ops::Deref for MetadataBlob {
69 fn deref(&self) -> &[u8] {
74 // A map from external crate numbers (as decoded from some crate file) to
75 // local crate numbers (as generated during this session). Each external
76 // crate may refer to types in other external crates, and each has their
78 pub(crate) type CrateNumMap = IndexVec<CrateNum, CrateNum>;
80 pub(crate) struct CrateMetadata {
81 /// The primary crate data - binary metadata blob.
84 // --- Some data pre-decoded from the metadata blob, usually for performance ---
85 /// NOTE(eddyb) we pass `'static` to a `'tcx` parameter because this
86 /// lifetime is only used behind `Lazy`, and therefore acts like a
87 /// universal (`for<'tcx>`), that is paired up with whichever `TyCtxt`
88 /// is being used to decode those values.
91 /// FIXME: Used only from queries and can use query cache,
92 /// so pre-decoding can probably be avoided.
93 trait_impls: FxHashMap<(u32, DefIndex), LazyArray<(DefIndex, Option<SimplifiedType>)>>,
94 /// Inherent impls which do not follow the normal coherence rules.
96 /// These can be introduced using either `#![rustc_coherence_is_core]`
97 /// or `#[rustc_allow_incoherent_impl]`.
98 incoherent_impls: FxHashMap<SimplifiedType, LazyArray<DefIndex>>,
99 /// Proc macro descriptions for this crate, if it's a proc macro crate.
100 raw_proc_macros: Option<&'static [ProcMacro]>,
101 /// Source maps for code from the crate.
102 source_map_import_info: OnceCell<Vec<ImportedSourceFile>>,
103 /// For every definition in this crate, maps its `DefPathHash` to its `DefIndex`.
104 def_path_hash_map: DefPathHashMapRef<'static>,
105 /// Likewise for ExpnHash.
106 expn_hash_map: OnceCell<UnhashMap<ExpnHash, ExpnIndex>>,
107 /// Used for decoding interpret::AllocIds in a cached & thread-safe manner.
108 alloc_decoding_state: AllocDecodingState,
109 /// Caches decoded `DefKey`s.
110 def_key_cache: Lock<FxHashMap<DefIndex, DefKey>>,
111 /// Caches decoded `DefPathHash`es.
112 def_path_hash_cache: Lock<FxHashMap<DefIndex, DefPathHash>>,
114 // --- Other significant crate properties ---
115 /// ID of this crate, from the current compilation session's point of view.
117 /// Maps crate IDs as they are were seen from this crate's compilation sessions into
118 /// IDs as they are seen from the current compilation session.
119 cnum_map: CrateNumMap,
120 /// Same ID set as `cnum_map` plus maybe some injected crates like panic runtime.
121 dependencies: Lock<Vec<CrateNum>>,
122 /// How to link (or not link) this crate to the currently compiled crate.
123 dep_kind: Lock<CrateDepKind>,
124 /// Filesystem location of this crate.
125 source: Lrc<CrateSource>,
126 /// Whether or not this crate should be consider a private dependency
127 /// for purposes of the 'exported_private_dependencies' lint
129 /// The hash for the host proc macro. Used to support `-Z dual-proc-macro`.
130 host_hash: Option<Svh>,
132 /// Additional data used for decoding `HygieneData` (e.g. `SyntaxContext`
134 /// Note that we store a `HygieneDecodeContext` for each `CrateMetadat`. This is
135 /// because `SyntaxContext` ids are not globally unique, so we need
136 /// to track which ids we've decoded on a per-crate basis.
137 hygiene_context: HygieneDecodeContext,
139 // --- Data used only for improving diagnostics ---
140 /// Information about the `extern crate` item or path that caused this crate to be loaded.
141 /// If this is `None`, then the crate was injected (e.g., by the allocator).
142 extern_crate: Lock<Option<ExternCrate>>,
145 /// Holds information about a rustc_span::SourceFile imported from another crate.
146 /// See `imported_source_files()` for more information.
147 struct ImportedSourceFile {
148 /// This SourceFile's byte-offset within the source_map of its original crate
149 original_start_pos: rustc_span::BytePos,
150 /// The end of this SourceFile within the source_map of its original crate
151 original_end_pos: rustc_span::BytePos,
152 /// The imported SourceFile's representation within the local source_map
153 translated_source_file: Lrc<rustc_span::SourceFile>,
156 pub(super) struct DecodeContext<'a, 'tcx> {
157 opaque: MemDecoder<'a>,
158 cdata: Option<CrateMetadataRef<'a>>,
159 blob: &'a MetadataBlob,
160 sess: Option<&'tcx Session>,
161 tcx: Option<TyCtxt<'tcx>>,
163 // Cache the last used source_file for translating spans as an optimization.
164 last_source_file_index: usize,
166 lazy_state: LazyState,
168 // Used for decoding interpret::AllocIds in a cached & thread-safe manner.
169 alloc_decoding_session: Option<AllocDecodingSession<'a>>,
172 /// Abstract over the various ways one can create metadata decoders.
173 pub(super) trait Metadata<'a, 'tcx>: Copy {
174 fn blob(self) -> &'a MetadataBlob;
176 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
179 fn sess(self) -> Option<&'tcx Session> {
182 fn tcx(self) -> Option<TyCtxt<'tcx>> {
186 fn decoder(self, pos: usize) -> DecodeContext<'a, 'tcx> {
187 let tcx = self.tcx();
189 opaque: MemDecoder::new(self.blob(), pos),
192 sess: self.sess().or(tcx.map(|tcx| tcx.sess)),
194 last_source_file_index: 0,
195 lazy_state: LazyState::NoNode,
196 alloc_decoding_session: self
198 .map(|cdata| cdata.cdata.alloc_decoding_state.new_decoding_session()),
203 impl<'a, 'tcx> Metadata<'a, 'tcx> for &'a MetadataBlob {
205 fn blob(self) -> &'a MetadataBlob {
210 impl<'a, 'tcx> Metadata<'a, 'tcx> for (&'a MetadataBlob, &'tcx Session) {
212 fn blob(self) -> &'a MetadataBlob {
217 fn sess(self) -> Option<&'tcx Session> {
218 let (_, sess) = self;
223 impl<'a, 'tcx> Metadata<'a, 'tcx> for CrateMetadataRef<'a> {
225 fn blob(self) -> &'a MetadataBlob {
229 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
234 impl<'a, 'tcx> Metadata<'a, 'tcx> for (CrateMetadataRef<'a>, &'tcx Session) {
236 fn blob(self) -> &'a MetadataBlob {
240 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
244 fn sess(self) -> Option<&'tcx Session> {
249 impl<'a, 'tcx> Metadata<'a, 'tcx> for (CrateMetadataRef<'a>, TyCtxt<'tcx>) {
251 fn blob(self) -> &'a MetadataBlob {
255 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
259 fn tcx(self) -> Option<TyCtxt<'tcx>> {
264 impl<T: ParameterizedOverTcx> LazyValue<T> {
265 fn decode<'a, 'tcx, M: Metadata<'a, 'tcx>>(self, metadata: M) -> T::Value<'tcx>
267 T::Value<'tcx>: Decodable<DecodeContext<'a, 'tcx>>,
269 let mut dcx = metadata.decoder(self.position.get());
270 dcx.lazy_state = LazyState::NodeStart(self.position);
271 T::Value::decode(&mut dcx)
275 struct DecodeIterator<'a, 'tcx, T> {
276 elem_counter: std::ops::Range<usize>,
277 dcx: DecodeContext<'a, 'tcx>,
278 _phantom: PhantomData<fn() -> T>,
281 impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> Iterator for DecodeIterator<'a, 'tcx, T> {
285 fn next(&mut self) -> Option<Self::Item> {
286 self.elem_counter.next().map(|_| T::decode(&mut self.dcx))
290 fn size_hint(&self) -> (usize, Option<usize>) {
291 self.elem_counter.size_hint()
295 impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> ExactSizeIterator
296 for DecodeIterator<'a, 'tcx, T>
298 fn len(&self) -> usize {
299 self.elem_counter.len()
303 unsafe impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> TrustedLen
304 for DecodeIterator<'a, 'tcx, T>
308 impl<T: ParameterizedOverTcx> LazyArray<T> {
309 fn decode<'a, 'tcx, M: Metadata<'a, 'tcx>>(
312 ) -> DecodeIterator<'a, 'tcx, T::Value<'tcx>>
314 T::Value<'tcx>: Decodable<DecodeContext<'a, 'tcx>>,
316 let mut dcx = metadata.decoder(self.position.get());
317 dcx.lazy_state = LazyState::NodeStart(self.position);
318 DecodeIterator { elem_counter: (0..self.num_elems), dcx, _phantom: PhantomData }
322 impl<'a, 'tcx> DecodeContext<'a, 'tcx> {
324 fn tcx(&self) -> TyCtxt<'tcx> {
325 debug_assert!(self.tcx.is_some(), "missing TyCtxt in DecodeContext");
330 pub fn blob(&self) -> &'a MetadataBlob {
335 pub fn cdata(&self) -> CrateMetadataRef<'a> {
336 debug_assert!(self.cdata.is_some(), "missing CrateMetadata in DecodeContext");
341 fn map_encoded_cnum_to_current(&self, cnum: CrateNum) -> CrateNum {
342 self.cdata().map_encoded_cnum_to_current(cnum)
346 fn read_lazy_offset_then<T>(&mut self, f: impl Fn(NonZeroUsize) -> T) -> T {
347 let distance = self.read_usize();
348 let position = match self.lazy_state {
349 LazyState::NoNode => bug!("read_lazy_with_meta: outside of a metadata node"),
350 LazyState::NodeStart(start) => {
351 let start = start.get();
352 assert!(distance <= start);
355 LazyState::Previous(last_pos) => last_pos.get() + distance,
357 let position = NonZeroUsize::new(position).unwrap();
358 self.lazy_state = LazyState::Previous(position);
362 fn read_lazy<T>(&mut self) -> LazyValue<T> {
363 self.read_lazy_offset_then(|pos| LazyValue::from_position(pos))
366 fn read_lazy_array<T>(&mut self, len: usize) -> LazyArray<T> {
367 self.read_lazy_offset_then(|pos| LazyArray::from_position_and_num_elems(pos, len))
370 fn read_lazy_table<I, T>(&mut self, len: usize) -> LazyTable<I, T> {
371 self.read_lazy_offset_then(|pos| LazyTable::from_position_and_encoded_size(pos, len))
375 pub fn read_raw_bytes(&mut self, len: usize) -> &[u8] {
376 self.opaque.read_raw_bytes(len)
380 impl<'a, 'tcx> TyDecoder for DecodeContext<'a, 'tcx> {
381 const CLEAR_CROSS_CRATE: bool = true;
383 type I = TyCtxt<'tcx>;
386 fn interner(&self) -> Self::I {
391 fn peek_byte(&self) -> u8 {
392 self.opaque.data[self.opaque.position()]
396 fn position(&self) -> usize {
397 self.opaque.position()
400 fn cached_ty_for_shorthand<F>(&mut self, shorthand: usize, or_insert_with: F) -> Ty<'tcx>
402 F: FnOnce(&mut Self) -> Ty<'tcx>,
404 let tcx = self.tcx();
406 let key = ty::CReaderCacheKey { cnum: Some(self.cdata().cnum), pos: shorthand };
408 if let Some(&ty) = tcx.ty_rcache.borrow().get(&key) {
412 let ty = or_insert_with(self);
413 tcx.ty_rcache.borrow_mut().insert(key, ty);
417 fn with_position<F, R>(&mut self, pos: usize, f: F) -> R
419 F: FnOnce(&mut Self) -> R,
421 let new_opaque = MemDecoder::new(self.opaque.data, pos);
422 let old_opaque = mem::replace(&mut self.opaque, new_opaque);
423 let old_state = mem::replace(&mut self.lazy_state, LazyState::NoNode);
425 self.opaque = old_opaque;
426 self.lazy_state = old_state;
430 fn decode_alloc_id(&mut self) -> rustc_middle::mir::interpret::AllocId {
431 if let Some(alloc_decoding_session) = self.alloc_decoding_session {
432 alloc_decoding_session.decode_alloc_id(self)
434 bug!("Attempting to decode interpret::AllocId without CrateMetadata")
439 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for CrateNum {
440 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> CrateNum {
441 let cnum = CrateNum::from_u32(d.read_u32());
442 d.map_encoded_cnum_to_current(cnum)
446 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for DefIndex {
447 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> DefIndex {
448 DefIndex::from_u32(d.read_u32())
452 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for ExpnIndex {
453 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> ExpnIndex {
454 ExpnIndex::from_u32(d.read_u32())
458 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for SyntaxContext {
459 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> SyntaxContext {
460 let cdata = decoder.cdata();
461 let sess = decoder.sess.unwrap();
462 let cname = cdata.root.name;
463 rustc_span::hygiene::decode_syntax_context(decoder, &cdata.hygiene_context, |_, id| {
464 debug!("SpecializedDecoder<SyntaxContext>: decoding {}", id);
469 .unwrap_or_else(|| panic!("Missing SyntaxContext {:?} for crate {:?}", id, cname))
470 .decode((cdata, sess))
475 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for ExpnId {
476 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> ExpnId {
477 let local_cdata = decoder.cdata();
478 let sess = decoder.sess.unwrap();
480 let cnum = CrateNum::decode(decoder);
481 let index = u32::decode(decoder);
483 let expn_id = rustc_span::hygiene::decode_expn_id(cnum, index, |expn_id| {
484 let ExpnId { krate: cnum, local_id: index } = expn_id;
485 // Lookup local `ExpnData`s in our own crate data. Foreign `ExpnData`s
486 // are stored in the owning crate, to avoid duplication.
487 debug_assert_ne!(cnum, LOCAL_CRATE);
488 let crate_data = if cnum == local_cdata.cnum {
491 local_cdata.cstore.get_crate_data(cnum)
493 let expn_data = crate_data
496 .get(crate_data, index)
498 .decode((crate_data, sess));
499 let expn_hash = crate_data
502 .get(crate_data, index)
504 .decode((crate_data, sess));
505 (expn_data, expn_hash)
511 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for Span {
512 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Span {
513 let ctxt = SyntaxContext::decode(decoder);
514 let tag = u8::decode(decoder);
516 if tag == TAG_PARTIAL_SPAN {
517 return DUMMY_SP.with_ctxt(ctxt);
520 debug_assert!(tag == TAG_VALID_SPAN_LOCAL || tag == TAG_VALID_SPAN_FOREIGN);
522 let lo = BytePos::decode(decoder);
523 let len = BytePos::decode(decoder);
526 let Some(sess) = decoder.sess else {
527 bug!("Cannot decode Span without Session.")
530 // There are two possibilities here:
531 // 1. This is a 'local span', which is located inside a `SourceFile`
532 // that came from this crate. In this case, we use the source map data
533 // encoded in this crate. This branch should be taken nearly all of the time.
534 // 2. This is a 'foreign span', which is located inside a `SourceFile`
535 // that came from a *different* crate (some crate upstream of the one
536 // whose metadata we're looking at). For example, consider this dependency graph:
540 // Suppose that we're currently compiling crate A, and start deserializing
541 // metadata from crate B. When we deserialize a Span from crate B's metadata,
542 // there are two possibilities:
544 // 1. The span references a file from crate B. This makes it a 'local' span,
545 // which means that we can use crate B's serialized source map information.
546 // 2. The span references a file from crate C. This makes it a 'foreign' span,
547 // which means we need to use Crate *C* (not crate B) to determine the source
548 // map information. We only record source map information for a file in the
549 // crate that 'owns' it, so deserializing a Span may require us to look at
550 // a transitive dependency.
552 // When we encode a foreign span, we adjust its 'lo' and 'high' values
553 // to be based on the *foreign* crate (e.g. crate C), not the crate
554 // we are writing metadata for (e.g. crate B). This allows us to
555 // treat the 'local' and 'foreign' cases almost identically during deserialization:
556 // we can call `imported_source_files` for the proper crate, and binary search
557 // through the returned slice using our span.
558 let imported_source_files = if tag == TAG_VALID_SPAN_LOCAL {
559 decoder.cdata().imported_source_files(sess)
561 // When we encode a proc-macro crate, all `Span`s should be encoded
562 // with `TAG_VALID_SPAN_LOCAL`
563 if decoder.cdata().root.is_proc_macro_crate() {
564 // Decode `CrateNum` as u32 - using `CrateNum::decode` will ICE
565 // since we don't have `cnum_map` populated.
566 let cnum = u32::decode(decoder);
568 "Decoding of crate {:?} tried to access proc-macro dep {:?}",
569 decoder.cdata().root.name,
573 // tag is TAG_VALID_SPAN_FOREIGN, checked by `debug_assert` above
574 let cnum = CrateNum::decode(decoder);
576 "SpecializedDecoder<Span>::specialized_decode: loading source files from cnum {:?}",
580 // Decoding 'foreign' spans should be rare enough that it's
581 // not worth it to maintain a per-CrateNum cache for `last_source_file_index`.
582 // We just set it to 0, to ensure that we don't try to access something out
583 // of bounds for our initial 'guess'
584 decoder.last_source_file_index = 0;
586 let foreign_data = decoder.cdata().cstore.get_crate_data(cnum);
587 foreign_data.imported_source_files(sess)
591 // Optimize for the case that most spans within a translated item
592 // originate from the same source_file.
593 let last_source_file = &imported_source_files[decoder.last_source_file_index];
595 if lo >= last_source_file.original_start_pos && lo <= last_source_file.original_end_pos
599 let index = imported_source_files
600 .binary_search_by_key(&lo, |source_file| source_file.original_start_pos)
601 .unwrap_or_else(|index| index - 1);
603 // Don't try to cache the index for foreign spans,
604 // as this would require a map from CrateNums to indices
605 if tag == TAG_VALID_SPAN_LOCAL {
606 decoder.last_source_file_index = index;
608 &imported_source_files[index]
612 // Make sure our binary search above is correct.
614 lo >= source_file.original_start_pos && lo <= source_file.original_end_pos,
615 "Bad binary search: lo={:?} source_file.original_start_pos={:?} source_file.original_end_pos={:?}",
617 source_file.original_start_pos,
618 source_file.original_end_pos
621 // Make sure we correctly filtered out invalid spans during encoding
623 hi >= source_file.original_start_pos && hi <= source_file.original_end_pos,
624 "Bad binary search: hi={:?} source_file.original_start_pos={:?} source_file.original_end_pos={:?}",
626 source_file.original_start_pos,
627 source_file.original_end_pos
631 (lo + source_file.translated_source_file.start_pos) - source_file.original_start_pos;
633 (hi + source_file.translated_source_file.start_pos) - source_file.original_start_pos;
635 // Do not try to decode parent for foreign spans.
636 Span::new(lo, hi, ctxt, None)
640 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for &'tcx [ty::abstract_const::Node<'tcx>] {
641 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Self {
642 ty::codec::RefDecodable::decode(d)
646 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for &'tcx [(ty::Predicate<'tcx>, Span)] {
647 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Self {
648 ty::codec::RefDecodable::decode(d)
652 impl<'a, 'tcx, T> Decodable<DecodeContext<'a, 'tcx>> for LazyValue<T> {
653 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self {
658 impl<'a, 'tcx, T> Decodable<DecodeContext<'a, 'tcx>> for LazyArray<T> {
659 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self {
660 let len = decoder.read_usize();
661 if len == 0 { LazyArray::empty() } else { decoder.read_lazy_array(len) }
665 impl<'a, 'tcx, I: Idx, T> Decodable<DecodeContext<'a, 'tcx>> for LazyTable<I, T> {
666 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self {
667 let len = decoder.read_usize();
668 decoder.read_lazy_table(len)
672 implement_ty_decoder!(DecodeContext<'a, 'tcx>);
675 pub(crate) fn new(metadata_ref: MetadataRef) -> MetadataBlob {
676 MetadataBlob(Lrc::new(metadata_ref))
679 pub(crate) fn is_compatible(&self) -> bool {
680 self.blob().starts_with(METADATA_HEADER)
683 pub(crate) fn get_rustc_version(&self) -> String {
684 LazyValue::<String>::from_position(NonZeroUsize::new(METADATA_HEADER.len() + 4).unwrap())
688 pub(crate) fn get_root(&self) -> CrateRoot {
689 let slice = &self.blob()[..];
690 let offset = METADATA_HEADER.len();
691 let pos = (((slice[offset + 0] as u32) << 24)
692 | ((slice[offset + 1] as u32) << 16)
693 | ((slice[offset + 2] as u32) << 8)
694 | ((slice[offset + 3] as u32) << 0)) as usize;
695 LazyValue::<CrateRoot>::from_position(NonZeroUsize::new(pos).unwrap()).decode(self)
698 pub(crate) fn list_crate_metadata(&self, out: &mut dyn io::Write) -> io::Result<()> {
699 let root = self.get_root();
700 writeln!(out, "Crate info:")?;
701 writeln!(out, "name {}{}", root.name, root.extra_filename)?;
702 writeln!(out, "hash {} stable_crate_id {:?}", root.hash, root.stable_crate_id)?;
703 writeln!(out, "proc_macro {:?}", root.proc_macro_data.is_some())?;
704 writeln!(out, "=External Dependencies=")?;
705 for (i, dep) in root.crate_deps.decode(self).enumerate() {
708 "{} {}{} hash {} host_hash {:?} kind {:?}",
723 pub(crate) fn is_proc_macro_crate(&self) -> bool {
724 self.proc_macro_data.is_some()
727 pub(crate) fn name(&self) -> Symbol {
731 pub(crate) fn hash(&self) -> Svh {
735 pub(crate) fn stable_crate_id(&self) -> StableCrateId {
739 pub(crate) fn triple(&self) -> &TargetTriple {
743 pub(crate) fn decode_crate_deps<'a>(
745 metadata: &'a MetadataBlob,
746 ) -> impl ExactSizeIterator<Item = CrateDep> + Captures<'a> {
747 self.crate_deps.decode(metadata)
751 impl<'a, 'tcx> CrateMetadataRef<'a> {
752 fn raw_proc_macro(self, id: DefIndex) -> &'a ProcMacro {
753 // DefIndex's in root.proc_macro_data have a one-to-one correspondence
754 // with items in 'raw_proc_macros'.
762 .position(|i| i == id)
764 &self.raw_proc_macros.unwrap()[pos]
767 fn opt_item_name(self, item_index: DefIndex) -> Option<Symbol> {
768 self.def_key(item_index).disambiguated_data.data.get_opt_name()
771 fn item_name(self, item_index: DefIndex) -> Symbol {
772 self.opt_item_name(item_index).expect("no encoded ident for item")
775 fn opt_item_ident(self, item_index: DefIndex, sess: &Session) -> Option<Ident> {
776 let name = self.opt_item_name(item_index)?;
778 self.root.tables.def_ident_span.get(self, item_index).unwrap().decode((self, sess));
779 Some(Ident::new(name, span))
782 fn item_ident(self, item_index: DefIndex, sess: &Session) -> Ident {
783 self.opt_item_ident(item_index, sess).expect("no encoded ident for item")
786 fn maybe_kind(self, item_id: DefIndex) -> Option<EntryKind> {
787 self.root.tables.kind.get(self, item_id).map(|k| k.decode(self))
791 pub(super) fn map_encoded_cnum_to_current(self, cnum: CrateNum) -> CrateNum {
792 if cnum == LOCAL_CRATE { self.cnum } else { self.cnum_map[cnum] }
795 fn kind(self, item_id: DefIndex) -> EntryKind {
796 self.maybe_kind(item_id).unwrap_or_else(|| {
798 "CrateMetadata::kind({:?}): id not found, in crate {:?} with number {}",
806 fn def_kind(self, item_id: DefIndex) -> DefKind {
807 self.root.tables.opt_def_kind.get(self, item_id).unwrap_or_else(|| {
809 "CrateMetadata::def_kind({:?}): id not found, in crate {:?} with number {}",
817 fn get_span(self, index: DefIndex, sess: &Session) -> Span {
822 .unwrap_or_else(|| panic!("Missing span for {:?}", index))
823 .decode((self, sess))
826 fn load_proc_macro(self, id: DefIndex, sess: &Session) -> SyntaxExtension {
827 let (name, kind, helper_attrs) = match *self.raw_proc_macro(id) {
828 ProcMacro::CustomDerive { trait_name, attributes, client } => {
830 attributes.iter().cloned().map(Symbol::intern).collect::<Vec<_>>();
833 SyntaxExtensionKind::Derive(Box::new(DeriveProcMacro { client })),
837 ProcMacro::Attr { name, client } => {
838 (name, SyntaxExtensionKind::Attr(Box::new(AttrProcMacro { client })), Vec::new())
840 ProcMacro::Bang { name, client } => {
841 (name, SyntaxExtensionKind::Bang(Box::new(BangProcMacro { client })), Vec::new())
845 let attrs: Vec<_> = self.get_item_attrs(id, sess).collect();
846 SyntaxExtension::new(
849 self.get_span(id, sess),
852 Symbol::intern(name),
857 fn get_variant(self, kind: &EntryKind, index: DefIndex, parent_did: DefId) -> ty::VariantDef {
858 let data = match kind {
859 EntryKind::Variant(data) | EntryKind::Struct(data) | EntryKind::Union(data) => {
865 let adt_kind = match kind {
866 EntryKind::Variant(_) => ty::AdtKind::Enum,
867 EntryKind::Struct(..) => ty::AdtKind::Struct,
868 EntryKind::Union(..) => ty::AdtKind::Union,
873 if adt_kind == ty::AdtKind::Enum { Some(self.local_def_id(index)) } else { None };
874 let ctor_did = data.ctor.map(|index| self.local_def_id(index));
877 self.item_name(index),
885 .unwrap_or_else(LazyArray::empty)
887 .map(|index| ty::FieldDef {
888 did: self.local_def_id(index),
889 name: self.item_name(index),
890 vis: self.get_visibility(index),
897 data.is_non_exhaustive,
901 fn get_adt_def(self, item_id: DefIndex, tcx: TyCtxt<'tcx>) -> ty::AdtDef<'tcx> {
902 let kind = self.kind(item_id);
903 let did = self.local_def_id(item_id);
905 let adt_kind = match kind {
906 EntryKind::Enum => ty::AdtKind::Enum,
907 EntryKind::Struct(_) => ty::AdtKind::Struct,
908 EntryKind::Union(_) => ty::AdtKind::Union,
909 _ => bug!("get_adt_def called on a non-ADT {:?}", did),
911 let repr = self.root.tables.repr_options.get(self, item_id).unwrap().decode(self);
913 let variants = if let ty::AdtKind::Enum = adt_kind {
918 .unwrap_or_else(LazyArray::empty)
920 .map(|index| self.get_variant(&self.kind(index), index, did))
923 std::iter::once(self.get_variant(&kind, item_id, did)).collect()
926 tcx.alloc_adt_def(did, adt_kind, variants, repr)
929 fn get_generics(self, item_id: DefIndex, sess: &Session) -> ty::Generics {
930 self.root.tables.generics_of.get(self, item_id).unwrap().decode((self, sess))
933 fn get_visibility(self, id: DefIndex) -> ty::Visibility {
934 self.root.tables.visibility.get(self, id).unwrap().decode(self)
937 fn get_trait_item_def_id(self, id: DefIndex) -> Option<DefId> {
938 self.root.tables.trait_item_def_id.get(self, id).map(|d| d.decode_from_cdata(self))
941 fn get_expn_that_defined(self, id: DefIndex, sess: &Session) -> ExpnId {
942 self.root.tables.expn_that_defined.get(self, id).unwrap().decode((self, sess))
945 fn get_debugger_visualizers(self) -> Vec<rustc_span::DebuggerVisualizerFile> {
946 self.root.debugger_visualizers.decode(self).collect::<Vec<_>>()
949 /// Iterates over all the stability attributes in the given crate.
950 fn get_lib_features(self, tcx: TyCtxt<'tcx>) -> &'tcx [(Symbol, Option<Symbol>)] {
951 tcx.arena.alloc_from_iter(self.root.lib_features.decode(self))
954 /// Iterates over the stability implications in the given crate (when a `#[unstable]` attribute
955 /// has an `implied_by` meta item, then the mapping from the implied feature to the actual
956 /// feature is a stability implication).
957 fn get_stability_implications(self, tcx: TyCtxt<'tcx>) -> &'tcx [(Symbol, Symbol)] {
958 tcx.arena.alloc_from_iter(self.root.stability_implications.decode(self))
961 /// Iterates over the language items in the given crate.
962 fn get_lang_items(self, tcx: TyCtxt<'tcx>) -> &'tcx [(DefId, usize)] {
963 tcx.arena.alloc_from_iter(
967 .map(move |(def_index, index)| (self.local_def_id(def_index), index)),
971 /// Iterates over the diagnostic items in the given crate.
972 fn get_diagnostic_items(self) -> DiagnosticItems {
973 let mut id_to_name = FxHashMap::default();
974 let name_to_id = self
978 .map(|(name, def_index)| {
979 let id = self.local_def_id(def_index);
980 id_to_name.insert(id, name);
984 DiagnosticItems { id_to_name, name_to_id }
987 /// Iterates over all named children of the given module,
988 /// including both proper items and reexports.
989 /// Module here is understood in name resolution sense - it can be a `mod` item,
990 /// or a crate root, or an enum, or a trait.
991 fn for_each_module_child(
994 mut callback: impl FnMut(ModChild),
997 if let Some(data) = &self.root.proc_macro_data {
998 // If we are loading as a proc macro, we want to return
999 // the view of this crate as a proc macro crate.
1000 if id == CRATE_DEF_INDEX {
1001 for def_index in data.macros.decode(self) {
1002 let raw_macro = self.raw_proc_macro(def_index);
1004 DefKind::Macro(macro_kind(raw_macro)),
1005 self.local_def_id(def_index),
1007 let ident = self.item_ident(def_index, sess);
1011 vis: ty::Visibility::Public,
1020 // Iterate over all children.
1021 if let Some(children) = self.root.tables.children.get(self, id) {
1022 for child_index in children.decode((self, sess)) {
1023 let ident = self.item_ident(child_index, sess);
1024 let kind = self.def_kind(child_index);
1025 let def_id = self.local_def_id(child_index);
1026 let res = Res::Def(kind, def_id);
1027 let vis = self.get_visibility(child_index);
1028 let span = self.get_span(child_index, sess);
1029 let macro_rules = match kind {
1030 DefKind::Macro(..) => match self.kind(child_index) {
1031 EntryKind::MacroDef(_, macro_rules) => macro_rules,
1032 _ => unreachable!(),
1037 callback(ModChild { ident, res, vis, span, macro_rules });
1039 // For non-re-export structs and variants add their constructors to children.
1040 // Re-export lists automatically contain constructors when necessary.
1042 DefKind::Struct => {
1043 if let Some((ctor_def_id, ctor_kind)) =
1044 self.get_ctor_def_id_and_kind(child_index)
1047 Res::Def(DefKind::Ctor(CtorOf::Struct, ctor_kind), ctor_def_id);
1048 let vis = self.get_visibility(ctor_def_id.index);
1058 DefKind::Variant => {
1059 // Braced variants, unlike structs, generate unusable names in
1060 // value namespace, they are reserved for possible future use.
1061 // It's ok to use the variant's id as a ctor id since an
1062 // error will be reported on any use of such resolution anyway.
1063 let (ctor_def_id, ctor_kind) = self
1064 .get_ctor_def_id_and_kind(child_index)
1065 .unwrap_or((def_id, CtorKind::Fictive));
1067 Res::Def(DefKind::Ctor(CtorOf::Variant, ctor_kind), ctor_def_id);
1068 let mut vis = self.get_visibility(ctor_def_id.index);
1069 if ctor_def_id == def_id && vis.is_public() {
1070 // For non-exhaustive variants lower the constructor visibility to
1071 // within the crate. We only need this for fictive constructors,
1072 // for other constructors correct visibilities
1073 // were already encoded in metadata.
1074 let mut attrs = self.get_item_attrs(def_id.index, sess);
1075 if attrs.any(|item| item.has_name(sym::non_exhaustive)) {
1076 let crate_def_id = self.local_def_id(CRATE_DEF_INDEX);
1077 vis = ty::Visibility::Restricted(crate_def_id);
1080 callback(ModChild { ident, res: ctor_res, vis, span, macro_rules: false });
1087 match self.kind(id) {
1088 EntryKind::Mod(exports) => {
1089 for exp in exports.decode((self, sess)) {
1093 EntryKind::Enum | EntryKind::Trait => {}
1094 _ => bug!("`for_each_module_child` is called on a non-module: {:?}", self.def_kind(id)),
1098 fn is_ctfe_mir_available(self, id: DefIndex) -> bool {
1099 self.root.tables.mir_for_ctfe.get(self, id).is_some()
1102 fn is_item_mir_available(self, id: DefIndex) -> bool {
1103 self.root.tables.optimized_mir.get(self, id).is_some()
1106 fn module_expansion(self, id: DefIndex, sess: &Session) -> ExpnId {
1107 match self.kind(id) {
1108 EntryKind::Mod(_) | EntryKind::Enum | EntryKind::Trait => {
1109 self.get_expn_that_defined(id, sess)
1111 _ => panic!("Expected module, found {:?}", self.local_def_id(id)),
1115 fn get_fn_has_self_parameter(self, id: DefIndex) -> bool {
1116 match self.kind(id) {
1117 EntryKind::AssocFn(data) => data.decode(self).has_self,
1122 fn get_associated_item_def_ids(
1126 ) -> impl Iterator<Item = DefId> + 'a {
1131 .unwrap_or_else(LazyArray::empty)
1132 .decode((self, sess))
1133 .map(move |child_index| self.local_def_id(child_index))
1136 fn get_associated_item(self, id: DefIndex) -> ty::AssocItem {
1137 let def_key = self.def_key(id);
1138 let parent = self.local_def_id(def_key.parent.unwrap());
1139 let name = self.item_name(id);
1141 let (kind, container, has_self) = match self.kind(id) {
1142 EntryKind::AssocConst(container) => (ty::AssocKind::Const, container, false),
1143 EntryKind::AssocFn(data) => {
1144 let data = data.decode(self);
1145 (ty::AssocKind::Fn, data.container, data.has_self)
1147 EntryKind::AssocType(container) => (ty::AssocKind::Type, container, false),
1148 _ => bug!("cannot get associated-item of `{:?}`", def_key),
1154 vis: self.get_visibility(id),
1155 defaultness: container.defaultness(),
1156 def_id: self.local_def_id(id),
1157 trait_item_def_id: self.get_trait_item_def_id(id),
1158 container: container.with_def_id(parent),
1159 fn_has_self_parameter: has_self,
1163 fn get_ctor_def_id_and_kind(self, node_id: DefIndex) -> Option<(DefId, CtorKind)> {
1164 match self.kind(node_id) {
1165 EntryKind::Struct(data) | EntryKind::Variant(data) => {
1166 let vdata = data.decode(self);
1167 vdata.ctor.map(|index| (self.local_def_id(index), vdata.ctor_kind))
1177 ) -> impl Iterator<Item = ast::Attribute> + 'a {
1182 .unwrap_or_else(|| {
1183 // Structure and variant constructors don't have any attributes encoded for them,
1184 // but we assume that someone passing a constructor ID actually wants to look at
1185 // the attributes on the corresponding struct or variant.
1186 let def_key = self.def_key(id);
1187 assert_eq!(def_key.disambiguated_data.data, DefPathData::Ctor);
1188 let parent_id = def_key.parent.expect("no parent for a constructor");
1192 .get(self, parent_id)
1193 .expect("no encoded attributes for a structure or variant")
1195 .decode((self, sess))
1198 fn get_struct_field_names(
1202 ) -> impl Iterator<Item = Spanned<Symbol>> + 'a {
1207 .unwrap_or_else(LazyArray::empty)
1209 .map(move |index| respan(self.get_span(index, sess), self.item_name(index)))
1212 fn get_struct_field_visibilities(self, id: DefIndex) -> impl Iterator<Item = Visibility> + 'a {
1217 .unwrap_or_else(LazyArray::empty)
1219 .map(move |field_index| self.get_visibility(field_index))
1222 fn get_inherent_implementations_for_type(
1226 ) -> &'tcx [DefId] {
1227 tcx.arena.alloc_from_iter(
1232 .unwrap_or_else(LazyArray::empty)
1234 .map(|index| self.local_def_id(index)),
1238 /// Decodes all inherent impls in the crate (for rustdoc).
1239 fn get_inherent_impls(self) -> impl Iterator<Item = (DefId, DefId)> + 'a {
1240 (0..self.root.tables.inherent_impls.size()).flat_map(move |i| {
1241 let ty_index = DefIndex::from_usize(i);
1242 let ty_def_id = self.local_def_id(ty_index);
1246 .get(self, ty_index)
1247 .unwrap_or_else(LazyArray::empty)
1249 .map(move |impl_index| (ty_def_id, self.local_def_id(impl_index)))
1253 /// Decodes all traits in the crate (for rustdoc and rustc diagnostics).
1254 fn get_traits(self) -> impl Iterator<Item = DefId> + 'a {
1255 self.root.traits.decode(self).map(move |index| self.local_def_id(index))
1258 /// Decodes all trait impls in the crate (for rustdoc).
1259 fn get_trait_impls(self) -> impl Iterator<Item = (DefId, DefId, Option<SimplifiedType>)> + 'a {
1260 self.cdata.trait_impls.iter().flat_map(move |(&(trait_cnum_raw, trait_index), impls)| {
1261 let trait_def_id = DefId {
1262 krate: self.cnum_map[CrateNum::from_u32(trait_cnum_raw)],
1265 impls.decode(self).map(move |(impl_index, simplified_self_ty)| {
1266 (trait_def_id, self.local_def_id(impl_index), simplified_self_ty)
1271 fn get_all_incoherent_impls(self) -> impl Iterator<Item = DefId> + 'a {
1275 .flat_map(move |impls| impls.decode(self).map(move |idx| self.local_def_id(idx)))
1278 fn get_incoherent_impls(self, tcx: TyCtxt<'tcx>, simp: SimplifiedType) -> &'tcx [DefId] {
1279 if let Some(impls) = self.cdata.incoherent_impls.get(&simp) {
1280 tcx.arena.alloc_from_iter(impls.decode(self).map(|idx| self.local_def_id(idx)))
1286 fn get_implementations_of_trait(
1289 trait_def_id: DefId,
1290 ) -> &'tcx [(DefId, Option<SimplifiedType>)] {
1291 if self.trait_impls.is_empty() {
1295 // Do a reverse lookup beforehand to avoid touching the crate_num
1296 // hash map in the loop below.
1297 let key = match self.reverse_translate_def_id(trait_def_id) {
1298 Some(def_id) => (def_id.krate.as_u32(), def_id.index),
1302 if let Some(impls) = self.trait_impls.get(&key) {
1303 tcx.arena.alloc_from_iter(
1306 .map(|(idx, simplified_self_ty)| (self.local_def_id(idx), simplified_self_ty)),
1313 fn get_trait_of_item(self, id: DefIndex) -> Option<DefId> {
1314 let def_key = self.def_key(id);
1315 match def_key.disambiguated_data.data {
1316 DefPathData::TypeNs(..) | DefPathData::ValueNs(..) => (),
1317 // Not an associated item
1320 def_key.parent.and_then(|parent_index| match self.kind(parent_index) {
1321 EntryKind::Trait | EntryKind::TraitAlias => Some(self.local_def_id(parent_index)),
1326 fn get_native_libraries(self, sess: &'a Session) -> impl Iterator<Item = NativeLib> + 'a {
1327 self.root.native_libraries.decode((self, sess))
1330 fn get_proc_macro_quoted_span(self, index: usize, sess: &Session) -> Span {
1333 .proc_macro_quoted_spans
1335 .unwrap_or_else(|| panic!("Missing proc macro quoted span: {:?}", index))
1336 .decode((self, sess))
1339 fn get_foreign_modules(self, sess: &'a Session) -> impl Iterator<Item = ForeignModule> + '_ {
1340 self.root.foreign_modules.decode((self, sess))
1343 fn get_dylib_dependency_formats(
1346 ) -> &'tcx [(CrateNum, LinkagePreference)] {
1347 tcx.arena.alloc_from_iter(
1348 self.root.dylib_dependency_formats.decode(self).enumerate().flat_map(|(i, link)| {
1349 let cnum = CrateNum::new(i + 1);
1350 link.map(|link| (self.cnum_map[cnum], link))
1355 fn get_missing_lang_items(self, tcx: TyCtxt<'tcx>) -> &'tcx [lang_items::LangItem] {
1356 tcx.arena.alloc_from_iter(self.root.lang_items_missing.decode(self))
1359 fn exported_symbols(
1362 ) -> &'tcx [(ExportedSymbol<'tcx>, SymbolExportInfo)] {
1363 tcx.arena.alloc_from_iter(self.root.exported_symbols.decode((self, tcx)))
1366 fn get_macro(self, id: DefIndex, sess: &Session) -> ast::MacroDef {
1367 match self.kind(id) {
1368 EntryKind::MacroDef(mac_args, macro_rules) => {
1369 ast::MacroDef { body: P(mac_args.decode((self, sess))), macro_rules }
1375 fn is_foreign_item(self, id: DefIndex) -> bool {
1376 match self.kind(id) {
1377 EntryKind::ForeignStatic | EntryKind::ForeignFn => true,
1383 fn def_key(self, index: DefIndex) -> DefKey {
1388 .or_insert_with(|| self.root.tables.def_keys.get(self, index).unwrap().decode(self))
1391 // Returns the path leading to the thing with this `id`.
1392 fn def_path(self, id: DefIndex) -> DefPath {
1393 debug!("def_path(cnum={:?}, id={:?})", self.cnum, id);
1394 DefPath::make(self.cnum, id, |parent| self.def_key(parent))
1397 fn def_path_hash_unlocked(
1400 def_path_hashes: &mut FxHashMap<DefIndex, DefPathHash>,
1404 .or_insert_with(|| self.root.tables.def_path_hashes.get(self, index).unwrap())
1408 fn def_path_hash(self, index: DefIndex) -> DefPathHash {
1409 let mut def_path_hashes = self.def_path_hash_cache.lock();
1410 self.def_path_hash_unlocked(index, &mut def_path_hashes)
1414 fn def_path_hash_to_def_index(self, hash: DefPathHash) -> DefIndex {
1415 self.def_path_hash_map.def_path_hash_to_def_index(&hash)
1418 fn expn_hash_to_expn_id(self, sess: &Session, index_guess: u32, hash: ExpnHash) -> ExpnId {
1419 debug_assert_eq!(ExpnId::from_hash(hash), None);
1420 let index_guess = ExpnIndex::from_u32(index_guess);
1421 let old_hash = self.root.expn_hashes.get(self, index_guess).map(|lazy| lazy.decode(self));
1423 let index = if old_hash == Some(hash) {
1424 // Fast path: the expn and its index is unchanged from the
1425 // previous compilation session. There is no need to decode anything
1429 // Slow path: We need to find out the new `DefIndex` of the provided
1430 // `DefPathHash`, if its still exists. This requires decoding every `DefPathHash`
1431 // stored in this crate.
1432 let map = self.cdata.expn_hash_map.get_or_init(|| {
1433 let end_id = self.root.expn_hashes.size() as u32;
1435 UnhashMap::with_capacity_and_hasher(end_id as usize, Default::default());
1436 for i in 0..end_id {
1437 let i = ExpnIndex::from_u32(i);
1438 if let Some(hash) = self.root.expn_hashes.get(self, i) {
1439 map.insert(hash.decode(self), i);
1447 let data = self.root.expn_data.get(self, index).unwrap().decode((self, sess));
1448 rustc_span::hygiene::register_expn_id(self.cnum, index, data, hash)
1451 /// Imports the source_map from an external crate into the source_map of the crate
1452 /// currently being compiled (the "local crate").
1454 /// The import algorithm works analogous to how AST items are inlined from an
1455 /// external crate's metadata:
1456 /// For every SourceFile in the external source_map an 'inline' copy is created in the
1457 /// local source_map. The correspondence relation between external and local
1458 /// SourceFiles is recorded in the `ImportedSourceFile` objects returned from this
1459 /// function. When an item from an external crate is later inlined into this
1460 /// crate, this correspondence information is used to translate the span
1461 /// information of the inlined item so that it refers the correct positions in
1462 /// the local source_map (see `<decoder::DecodeContext as SpecializedDecoder<Span>>`).
1464 /// The import algorithm in the function below will reuse SourceFiles already
1465 /// existing in the local source_map. For example, even if the SourceFile of some
1466 /// source file of libstd gets imported many times, there will only ever be
1467 /// one SourceFile object for the corresponding file in the local source_map.
1469 /// Note that imported SourceFiles do not actually contain the source code of the
1470 /// file they represent, just information about length, line breaks, and
1471 /// multibyte characters. This information is enough to generate valid debuginfo
1472 /// for items inlined from other crates.
1474 /// Proc macro crates don't currently export spans, so this function does not have
1475 /// to work for them.
1476 fn imported_source_files(self, sess: &Session) -> &'a [ImportedSourceFile] {
1477 // Translate the virtual `/rustc/$hash` prefix back to a real directory
1478 // that should hold actual sources, where possible.
1480 // NOTE: if you update this, you might need to also update bootstrap's code for generating
1481 // the `rust-src` component in `Src::run` in `src/bootstrap/dist.rs`.
1482 let virtual_rust_source_base_dir = [
1483 option_env!("CFG_VIRTUAL_RUST_SOURCE_BASE_DIR").map(PathBuf::from),
1484 sess.opts.unstable_opts.simulate_remapped_rust_src_base.clone(),
1488 // Only spend time on further checks if we have what to translate *to*.
1489 sess.opts.real_rust_source_base_dir.is_some()
1490 // Some tests need the translation to be always skipped.
1491 && sess.opts.unstable_opts.translate_remapped_path_to_local_path
1494 .filter(|virtual_dir| {
1495 // Don't translate away `/rustc/$hash` if we're still remapping to it,
1496 // since that means we're still building `std`/`rustc` that need it,
1497 // and we don't want the real path to leak into codegen/debuginfo.
1498 !sess.opts.remap_path_prefix.iter().any(|(_from, to)| to == virtual_dir)
1500 .collect::<Vec<_>>();
1502 let try_to_translate_virtual_to_real = |name: &mut rustc_span::FileName| {
1504 "try_to_translate_virtual_to_real(name={:?}): \
1505 virtual_rust_source_base_dir={:?}, real_rust_source_base_dir={:?}",
1506 name, virtual_rust_source_base_dir, sess.opts.real_rust_source_base_dir,
1509 for virtual_dir in &virtual_rust_source_base_dir {
1510 if let Some(real_dir) = &sess.opts.real_rust_source_base_dir {
1511 if let rustc_span::FileName::Real(old_name) = name {
1512 if let rustc_span::RealFileName::Remapped { local_path: _, virtual_name } =
1515 if let Ok(rest) = virtual_name.strip_prefix(virtual_dir) {
1516 let virtual_name = virtual_name.clone();
1518 // The std library crates are in
1519 // `$sysroot/lib/rustlib/src/rust/library`, whereas other crates
1520 // may be in `$sysroot/lib/rustlib/src/rust/` directly. So we
1521 // detect crates from the std libs and handle them specially.
1522 const STD_LIBS: &[&str] = &[
1532 "profiler_builtins",
1534 "rustc-std-workspace-core",
1535 "rustc-std-workspace-alloc",
1536 "rustc-std-workspace-std",
1539 let is_std_lib = STD_LIBS.iter().any(|l| rest.starts_with(l));
1541 let new_path = if is_std_lib {
1542 real_dir.join("library").join(rest)
1548 "try_to_translate_virtual_to_real: `{}` -> `{}`",
1549 virtual_name.display(),
1552 let new_name = rustc_span::RealFileName::Remapped {
1553 local_path: Some(new_path),
1556 *old_name = new_name;
1564 self.cdata.source_map_import_info.get_or_init(|| {
1565 let external_source_map = self.root.source_map.decode(self);
1568 .map(|source_file_to_import| {
1569 // We can't reuse an existing SourceFile, so allocate a new one
1570 // containing the information we need.
1571 let rustc_span::SourceFile {
1582 } = source_file_to_import;
1584 // If this file is under $sysroot/lib/rustlib/src/ but has not been remapped
1585 // during rust bootstrapping by `remap-debuginfo = true`, and the user
1586 // wish to simulate that behaviour by -Z simulate-remapped-rust-src-base,
1587 // then we change `name` to a similar state as if the rust was bootstrapped
1588 // with `remap-debuginfo = true`.
1589 // This is useful for testing so that tests about the effects of
1590 // `try_to_translate_virtual_to_real` don't have to worry about how the
1591 // compiler is bootstrapped.
1592 if let Some(virtual_dir) =
1593 &sess.opts.unstable_opts.simulate_remapped_rust_src_base
1595 if let Some(real_dir) = &sess.opts.real_rust_source_base_dir {
1596 if let rustc_span::FileName::Real(ref mut old_name) = name {
1597 if let rustc_span::RealFileName::LocalPath(local) = old_name {
1598 if let Ok(rest) = local.strip_prefix(real_dir) {
1599 *old_name = rustc_span::RealFileName::Remapped {
1601 virtual_name: virtual_dir.join(rest),
1609 // If this file's path has been remapped to `/rustc/$hash`,
1610 // we might be able to reverse that (also see comments above,
1611 // on `try_to_translate_virtual_to_real`).
1612 try_to_translate_virtual_to_real(&mut name);
1614 let source_length = (end_pos - start_pos).to_usize();
1616 let local_version = sess.source_map().new_imported_source_file(
1630 "CrateMetaData::imported_source_files alloc \
1631 source_file {:?} original (start_pos {:?} end_pos {:?}) \
1632 translated (start_pos {:?} end_pos {:?})",
1636 local_version.start_pos,
1637 local_version.end_pos
1640 ImportedSourceFile {
1641 original_start_pos: start_pos,
1642 original_end_pos: end_pos,
1643 translated_source_file: local_version,
1650 fn get_generator_diagnostic_data(
1654 ) -> Option<GeneratorDiagnosticData<'tcx>> {
1657 .generator_diagnostic_data
1659 .map(|param| param.decode((self, tcx)))
1660 .map(|generator_data| GeneratorDiagnosticData {
1661 generator_interior_types: generator_data.generator_interior_types,
1662 hir_owner: generator_data.hir_owner,
1663 nodes_types: generator_data.nodes_types,
1664 adjustments: generator_data.adjustments,
1668 fn get_may_have_doc_links(self, index: DefIndex) -> bool {
1669 self.root.tables.may_have_doc_links.get(self, index).is_some()
1672 fn get_is_intrinsic(self, index: DefIndex) -> bool {
1673 self.root.tables.is_intrinsic.get(self, index).is_some()
1677 impl CrateMetadata {
1683 raw_proc_macros: Option<&'static [ProcMacro]>,
1685 cnum_map: CrateNumMap,
1686 dep_kind: CrateDepKind,
1687 source: CrateSource,
1689 host_hash: Option<Svh>,
1690 ) -> CrateMetadata {
1691 let trait_impls = root
1693 .decode((&blob, sess))
1694 .map(|trait_impls| (trait_impls.trait_id, trait_impls.impls))
1696 let alloc_decoding_state =
1697 AllocDecodingState::new(root.interpret_alloc_index.decode(&blob).collect());
1698 let dependencies = Lock::new(cnum_map.iter().cloned().collect());
1700 // Pre-decode the DefPathHash->DefIndex table. This is a cheap operation
1701 // that does not copy any data. It just does some data verification.
1702 let def_path_hash_map = root.def_path_hash_map.decode(&blob);
1704 let mut cdata = CrateMetadata {
1708 incoherent_impls: Default::default(),
1710 source_map_import_info: OnceCell::new(),
1712 expn_hash_map: Default::default(),
1713 alloc_decoding_state,
1717 dep_kind: Lock::new(dep_kind),
1718 source: Lrc::new(source),
1721 extern_crate: Lock::new(None),
1722 hygiene_context: Default::default(),
1723 def_key_cache: Default::default(),
1724 def_path_hash_cache: Default::default(),
1727 // Need `CrateMetadataRef` to decode `DefId`s in simplified types.
1728 cdata.incoherent_impls = cdata
1731 .decode(CrateMetadataRef { cdata: &cdata, cstore })
1732 .map(|incoherent_impls| (incoherent_impls.self_ty, incoherent_impls.impls))
1738 pub(crate) fn dependencies(&self) -> LockGuard<'_, Vec<CrateNum>> {
1739 self.dependencies.borrow()
1742 pub(crate) fn add_dependency(&self, cnum: CrateNum) {
1743 self.dependencies.borrow_mut().push(cnum);
1746 pub(crate) fn update_extern_crate(&self, new_extern_crate: ExternCrate) -> bool {
1747 let mut extern_crate = self.extern_crate.borrow_mut();
1748 let update = Some(new_extern_crate.rank()) > extern_crate.as_ref().map(ExternCrate::rank);
1750 *extern_crate = Some(new_extern_crate);
1755 pub(crate) fn source(&self) -> &CrateSource {
1759 pub(crate) fn dep_kind(&self) -> CrateDepKind {
1760 *self.dep_kind.lock()
1763 pub(crate) fn update_dep_kind(&self, f: impl FnOnce(CrateDepKind) -> CrateDepKind) {
1764 self.dep_kind.with_lock(|dep_kind| *dep_kind = f(*dep_kind))
1767 pub(crate) fn required_panic_strategy(&self) -> Option<PanicStrategy> {
1768 self.root.required_panic_strategy
1771 pub(crate) fn needs_panic_runtime(&self) -> bool {
1772 self.root.needs_panic_runtime
1775 pub(crate) fn is_panic_runtime(&self) -> bool {
1776 self.root.panic_runtime
1779 pub(crate) fn is_profiler_runtime(&self) -> bool {
1780 self.root.profiler_runtime
1783 pub(crate) fn needs_allocator(&self) -> bool {
1784 self.root.needs_allocator
1787 pub(crate) fn has_global_allocator(&self) -> bool {
1788 self.root.has_global_allocator
1791 pub(crate) fn has_default_lib_allocator(&self) -> bool {
1792 self.root.has_default_lib_allocator
1795 pub(crate) fn is_proc_macro_crate(&self) -> bool {
1796 self.root.is_proc_macro_crate()
1799 pub(crate) fn name(&self) -> Symbol {
1803 pub(crate) fn stable_crate_id(&self) -> StableCrateId {
1804 self.root.stable_crate_id
1807 pub(crate) fn hash(&self) -> Svh {
1811 fn num_def_ids(&self) -> usize {
1812 self.root.tables.def_keys.size()
1815 fn local_def_id(&self, index: DefIndex) -> DefId {
1816 DefId { krate: self.cnum, index }
1819 // Translate a DefId from the current compilation environment to a DefId
1820 // for an external crate.
1821 fn reverse_translate_def_id(&self, did: DefId) -> Option<DefId> {
1822 for (local, &global) in self.cnum_map.iter_enumerated() {
1823 if global == did.krate {
1824 return Some(DefId { krate: local, index: did.index });
1832 // Cannot be implemented on 'ProcMacro', as libproc_macro
1833 // does not depend on librustc_ast
1834 fn macro_kind(raw: &ProcMacro) -> MacroKind {
1836 ProcMacro::CustomDerive { .. } => MacroKind::Derive,
1837 ProcMacro::Attr { .. } => MacroKind::Attr,
1838 ProcMacro::Bang { .. } => MacroKind::Bang,