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::thir;
25 use rustc_middle::ty::codec::TyDecoder;
26 use rustc_middle::ty::fast_reject::SimplifiedType;
27 use rustc_middle::ty::GeneratorDiagnosticData;
28 use rustc_middle::ty::{self, ParameterizedOverTcx, Ty, TyCtxt, Visibility};
29 use rustc_serialize::opaque::MemDecoder;
30 use rustc_serialize::{Decodable, Decoder};
31 use rustc_session::cstore::{
32 CrateSource, ExternCrate, ForeignModule, LinkagePreference, NativeLib,
34 use rustc_session::Session;
35 use rustc_span::hygiene::{ExpnIndex, MacroKind};
36 use rustc_span::source_map::{respan, Spanned};
37 use rustc_span::symbol::{sym, Ident, Symbol};
38 use rustc_span::{self, BytePos, ExpnId, Pos, Span, SyntaxContext, DUMMY_SP};
40 use proc_macro::bridge::client::ProcMacro;
42 use std::iter::TrustedLen;
44 use std::num::NonZeroUsize;
48 pub(super) use cstore_impl::provide;
49 pub use cstore_impl::provide_extern;
50 use rustc_span::hygiene::HygieneDecodeContext;
54 /// A reference to the raw binary version of crate metadata.
55 /// A `MetadataBlob` internally is just a reference counted pointer to
56 /// the actual data, so cloning it is cheap.
58 pub(crate) struct MetadataBlob(Lrc<MetadataRef>);
60 // This is needed so we can create an OwningRef into the blob.
61 // The data behind a `MetadataBlob` has a stable address because it is
62 // contained within an Rc/Arc.
63 unsafe impl rustc_data_structures::owning_ref::StableAddress for MetadataBlob {}
65 // This is needed so we can create an OwningRef into the blob.
66 impl std::ops::Deref for MetadataBlob {
70 fn deref(&self) -> &[u8] {
75 // A map from external crate numbers (as decoded from some crate file) to
76 // local crate numbers (as generated during this session). Each external
77 // crate may refer to types in other external crates, and each has their
79 pub(crate) type CrateNumMap = IndexVec<CrateNum, CrateNum>;
81 pub(crate) struct CrateMetadata {
82 /// The primary crate data - binary metadata blob.
85 // --- Some data pre-decoded from the metadata blob, usually for performance ---
86 /// NOTE(eddyb) we pass `'static` to a `'tcx` parameter because this
87 /// lifetime is only used behind `Lazy`, and therefore acts like a
88 /// universal (`for<'tcx>`), that is paired up with whichever `TyCtxt`
89 /// is being used to decode those values.
92 /// FIXME: Used only from queries and can use query cache,
93 /// so pre-decoding can probably be avoided.
94 trait_impls: FxHashMap<(u32, DefIndex), LazyArray<(DefIndex, Option<SimplifiedType>)>>,
95 /// Inherent impls which do not follow the normal coherence rules.
97 /// These can be introduced using either `#![rustc_coherence_is_core]`
98 /// or `#[rustc_allow_incoherent_impl]`.
99 incoherent_impls: FxHashMap<SimplifiedType, LazyArray<DefIndex>>,
100 /// Proc macro descriptions for this crate, if it's a proc macro crate.
101 raw_proc_macros: Option<&'static [ProcMacro]>,
102 /// Source maps for code from the crate.
103 source_map_import_info: OnceCell<Vec<ImportedSourceFile>>,
104 /// For every definition in this crate, maps its `DefPathHash` to its `DefIndex`.
105 def_path_hash_map: DefPathHashMapRef<'static>,
106 /// Likewise for ExpnHash.
107 expn_hash_map: OnceCell<UnhashMap<ExpnHash, ExpnIndex>>,
108 /// Used for decoding interpret::AllocIds in a cached & thread-safe manner.
109 alloc_decoding_state: AllocDecodingState,
110 /// Caches decoded `DefKey`s.
111 def_key_cache: Lock<FxHashMap<DefIndex, DefKey>>,
112 /// Caches decoded `DefPathHash`es.
113 def_path_hash_cache: Lock<FxHashMap<DefIndex, DefPathHash>>,
115 // --- Other significant crate properties ---
116 /// ID of this crate, from the current compilation session's point of view.
118 /// Maps crate IDs as they are were seen from this crate's compilation sessions into
119 /// IDs as they are seen from the current compilation session.
120 cnum_map: CrateNumMap,
121 /// Same ID set as `cnum_map` plus maybe some injected crates like panic runtime.
122 dependencies: Lock<Vec<CrateNum>>,
123 /// How to link (or not link) this crate to the currently compiled crate.
124 dep_kind: Lock<CrateDepKind>,
125 /// Filesystem location of this crate.
126 source: Lrc<CrateSource>,
127 /// Whether or not this crate should be consider a private dependency
128 /// for purposes of the 'exported_private_dependencies' lint
130 /// The hash for the host proc macro. Used to support `-Z dual-proc-macro`.
131 host_hash: Option<Svh>,
133 /// Additional data used for decoding `HygieneData` (e.g. `SyntaxContext`
135 /// Note that we store a `HygieneDecodeContext` for each `CrateMetadat`. This is
136 /// because `SyntaxContext` ids are not globally unique, so we need
137 /// to track which ids we've decoded on a per-crate basis.
138 hygiene_context: HygieneDecodeContext,
140 // --- Data used only for improving diagnostics ---
141 /// Information about the `extern crate` item or path that caused this crate to be loaded.
142 /// If this is `None`, then the crate was injected (e.g., by the allocator).
143 extern_crate: Lock<Option<ExternCrate>>,
146 /// Holds information about a rustc_span::SourceFile imported from another crate.
147 /// See `imported_source_files()` for more information.
148 struct ImportedSourceFile {
149 /// This SourceFile's byte-offset within the source_map of its original crate
150 original_start_pos: rustc_span::BytePos,
151 /// The end of this SourceFile within the source_map of its original crate
152 original_end_pos: rustc_span::BytePos,
153 /// The imported SourceFile's representation within the local source_map
154 translated_source_file: Lrc<rustc_span::SourceFile>,
157 pub(super) struct DecodeContext<'a, 'tcx> {
158 opaque: MemDecoder<'a>,
159 cdata: Option<CrateMetadataRef<'a>>,
160 blob: &'a MetadataBlob,
161 sess: Option<&'tcx Session>,
162 tcx: Option<TyCtxt<'tcx>>,
164 // Cache the last used source_file for translating spans as an optimization.
165 last_source_file_index: usize,
167 lazy_state: LazyState,
169 // Used for decoding interpret::AllocIds in a cached & thread-safe manner.
170 alloc_decoding_session: Option<AllocDecodingSession<'a>>,
173 /// Abstract over the various ways one can create metadata decoders.
174 pub(super) trait Metadata<'a, 'tcx>: Copy {
175 fn blob(self) -> &'a MetadataBlob;
177 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
180 fn sess(self) -> Option<&'tcx Session> {
183 fn tcx(self) -> Option<TyCtxt<'tcx>> {
187 fn decoder(self, pos: usize) -> DecodeContext<'a, 'tcx> {
188 let tcx = self.tcx();
190 opaque: MemDecoder::new(self.blob(), pos),
193 sess: self.sess().or(tcx.map(|tcx| tcx.sess)),
195 last_source_file_index: 0,
196 lazy_state: LazyState::NoNode,
197 alloc_decoding_session: self
199 .map(|cdata| cdata.cdata.alloc_decoding_state.new_decoding_session()),
204 impl<'a, 'tcx> Metadata<'a, 'tcx> for &'a MetadataBlob {
206 fn blob(self) -> &'a MetadataBlob {
211 impl<'a, 'tcx> Metadata<'a, 'tcx> for (&'a MetadataBlob, &'tcx Session) {
213 fn blob(self) -> &'a MetadataBlob {
218 fn sess(self) -> Option<&'tcx Session> {
219 let (_, sess) = self;
224 impl<'a, 'tcx> Metadata<'a, 'tcx> for CrateMetadataRef<'a> {
226 fn blob(self) -> &'a MetadataBlob {
230 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
235 impl<'a, 'tcx> Metadata<'a, 'tcx> for (CrateMetadataRef<'a>, &'tcx Session) {
237 fn blob(self) -> &'a MetadataBlob {
241 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
245 fn sess(self) -> Option<&'tcx Session> {
250 impl<'a, 'tcx> Metadata<'a, 'tcx> for (CrateMetadataRef<'a>, TyCtxt<'tcx>) {
252 fn blob(self) -> &'a MetadataBlob {
256 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
260 fn tcx(self) -> Option<TyCtxt<'tcx>> {
265 impl<T: ParameterizedOverTcx> LazyValue<T> {
266 fn decode<'a, 'tcx, M: Metadata<'a, 'tcx>>(self, metadata: M) -> T::Value<'tcx>
268 T::Value<'tcx>: Decodable<DecodeContext<'a, 'tcx>>,
270 let mut dcx = metadata.decoder(self.position.get());
271 dcx.lazy_state = LazyState::NodeStart(self.position);
272 T::Value::decode(&mut dcx)
276 struct DecodeIterator<'a, 'tcx, T> {
277 elem_counter: std::ops::Range<usize>,
278 dcx: DecodeContext<'a, 'tcx>,
279 _phantom: PhantomData<fn() -> T>,
282 impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> Iterator for DecodeIterator<'a, 'tcx, T> {
286 fn next(&mut self) -> Option<Self::Item> {
287 self.elem_counter.next().map(|_| T::decode(&mut self.dcx))
291 fn size_hint(&self) -> (usize, Option<usize>) {
292 self.elem_counter.size_hint()
296 impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> ExactSizeIterator
297 for DecodeIterator<'a, 'tcx, T>
299 fn len(&self) -> usize {
300 self.elem_counter.len()
304 unsafe impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> TrustedLen
305 for DecodeIterator<'a, 'tcx, T>
309 impl<T: ParameterizedOverTcx> LazyArray<T> {
310 fn decode<'a, 'tcx, M: Metadata<'a, 'tcx>>(
313 ) -> DecodeIterator<'a, 'tcx, T::Value<'tcx>>
315 T::Value<'tcx>: Decodable<DecodeContext<'a, 'tcx>>,
317 let mut dcx = metadata.decoder(self.position.get());
318 dcx.lazy_state = LazyState::NodeStart(self.position);
319 DecodeIterator { elem_counter: (0..self.num_elems), dcx, _phantom: PhantomData }
323 impl<'a, 'tcx> DecodeContext<'a, 'tcx> {
325 fn tcx(&self) -> TyCtxt<'tcx> {
326 debug_assert!(self.tcx.is_some(), "missing TyCtxt in DecodeContext");
331 pub fn blob(&self) -> &'a MetadataBlob {
336 pub fn cdata(&self) -> CrateMetadataRef<'a> {
337 debug_assert!(self.cdata.is_some(), "missing CrateMetadata in DecodeContext");
342 fn map_encoded_cnum_to_current(&self, cnum: CrateNum) -> CrateNum {
343 self.cdata().map_encoded_cnum_to_current(cnum)
347 fn read_lazy_offset_then<T>(&mut self, f: impl Fn(NonZeroUsize) -> T) -> T {
348 let distance = self.read_usize();
349 let position = match self.lazy_state {
350 LazyState::NoNode => bug!("read_lazy_with_meta: outside of a metadata node"),
351 LazyState::NodeStart(start) => {
352 let start = start.get();
353 assert!(distance <= start);
356 LazyState::Previous(last_pos) => last_pos.get() + distance,
358 let position = NonZeroUsize::new(position).unwrap();
359 self.lazy_state = LazyState::Previous(position);
363 fn read_lazy<T>(&mut self) -> LazyValue<T> {
364 self.read_lazy_offset_then(|pos| LazyValue::from_position(pos))
367 fn read_lazy_array<T>(&mut self, len: usize) -> LazyArray<T> {
368 self.read_lazy_offset_then(|pos| LazyArray::from_position_and_num_elems(pos, len))
371 fn read_lazy_table<I, T>(&mut self, len: usize) -> LazyTable<I, T> {
372 self.read_lazy_offset_then(|pos| LazyTable::from_position_and_encoded_size(pos, len))
376 pub fn read_raw_bytes(&mut self, len: usize) -> &[u8] {
377 self.opaque.read_raw_bytes(len)
381 impl<'a, 'tcx> TyDecoder for DecodeContext<'a, 'tcx> {
382 const CLEAR_CROSS_CRATE: bool = true;
384 type I = TyCtxt<'tcx>;
387 fn interner(&self) -> Self::I {
392 fn peek_byte(&self) -> u8 {
393 self.opaque.data[self.opaque.position()]
397 fn position(&self) -> usize {
398 self.opaque.position()
401 fn cached_ty_for_shorthand<F>(&mut self, shorthand: usize, or_insert_with: F) -> Ty<'tcx>
403 F: FnOnce(&mut Self) -> Ty<'tcx>,
405 let tcx = self.tcx();
407 let key = ty::CReaderCacheKey { cnum: Some(self.cdata().cnum), pos: shorthand };
409 if let Some(&ty) = tcx.ty_rcache.borrow().get(&key) {
413 let ty = or_insert_with(self);
414 tcx.ty_rcache.borrow_mut().insert(key, ty);
418 fn with_position<F, R>(&mut self, pos: usize, f: F) -> R
420 F: FnOnce(&mut Self) -> R,
422 let new_opaque = MemDecoder::new(self.opaque.data, pos);
423 let old_opaque = mem::replace(&mut self.opaque, new_opaque);
424 let old_state = mem::replace(&mut self.lazy_state, LazyState::NoNode);
426 self.opaque = old_opaque;
427 self.lazy_state = old_state;
431 fn decode_alloc_id(&mut self) -> rustc_middle::mir::interpret::AllocId {
432 if let Some(alloc_decoding_session) = self.alloc_decoding_session {
433 alloc_decoding_session.decode_alloc_id(self)
435 bug!("Attempting to decode interpret::AllocId without CrateMetadata")
440 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for CrateNum {
441 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> CrateNum {
442 let cnum = CrateNum::from_u32(d.read_u32());
443 d.map_encoded_cnum_to_current(cnum)
447 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for DefIndex {
448 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> DefIndex {
449 DefIndex::from_u32(d.read_u32())
453 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for ExpnIndex {
454 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> ExpnIndex {
455 ExpnIndex::from_u32(d.read_u32())
459 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for SyntaxContext {
460 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> SyntaxContext {
461 let cdata = decoder.cdata();
462 let sess = decoder.sess.unwrap();
463 let cname = cdata.root.name;
464 rustc_span::hygiene::decode_syntax_context(decoder, &cdata.hygiene_context, |_, id| {
465 debug!("SpecializedDecoder<SyntaxContext>: decoding {}", id);
470 .unwrap_or_else(|| panic!("Missing SyntaxContext {:?} for crate {:?}", id, cname))
471 .decode((cdata, sess))
476 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for ExpnId {
477 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> ExpnId {
478 let local_cdata = decoder.cdata();
479 let sess = decoder.sess.unwrap();
481 let cnum = CrateNum::decode(decoder);
482 let index = u32::decode(decoder);
484 let expn_id = rustc_span::hygiene::decode_expn_id(cnum, index, |expn_id| {
485 let ExpnId { krate: cnum, local_id: index } = expn_id;
486 // Lookup local `ExpnData`s in our own crate data. Foreign `ExpnData`s
487 // are stored in the owning crate, to avoid duplication.
488 debug_assert_ne!(cnum, LOCAL_CRATE);
489 let crate_data = if cnum == local_cdata.cnum {
492 local_cdata.cstore.get_crate_data(cnum)
494 let expn_data = crate_data
497 .get(crate_data, index)
499 .decode((crate_data, sess));
500 let expn_hash = crate_data
503 .get(crate_data, index)
505 .decode((crate_data, sess));
506 (expn_data, expn_hash)
512 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for Span {
513 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Span {
514 let ctxt = SyntaxContext::decode(decoder);
515 let tag = u8::decode(decoder);
517 if tag == TAG_PARTIAL_SPAN {
518 return DUMMY_SP.with_ctxt(ctxt);
521 debug_assert!(tag == TAG_VALID_SPAN_LOCAL || tag == TAG_VALID_SPAN_FOREIGN);
523 let lo = BytePos::decode(decoder);
524 let len = BytePos::decode(decoder);
527 let Some(sess) = decoder.sess else {
528 bug!("Cannot decode Span without Session.")
531 // There are two possibilities here:
532 // 1. This is a 'local span', which is located inside a `SourceFile`
533 // that came from this crate. In this case, we use the source map data
534 // encoded in this crate. This branch should be taken nearly all of the time.
535 // 2. This is a 'foreign span', which is located inside a `SourceFile`
536 // that came from a *different* crate (some crate upstream of the one
537 // whose metadata we're looking at). For example, consider this dependency graph:
541 // Suppose that we're currently compiling crate A, and start deserializing
542 // metadata from crate B. When we deserialize a Span from crate B's metadata,
543 // there are two possibilities:
545 // 1. The span references a file from crate B. This makes it a 'local' span,
546 // which means that we can use crate B's serialized source map information.
547 // 2. The span references a file from crate C. This makes it a 'foreign' span,
548 // which means we need to use Crate *C* (not crate B) to determine the source
549 // map information. We only record source map information for a file in the
550 // crate that 'owns' it, so deserializing a Span may require us to look at
551 // a transitive dependency.
553 // When we encode a foreign span, we adjust its 'lo' and 'high' values
554 // to be based on the *foreign* crate (e.g. crate C), not the crate
555 // we are writing metadata for (e.g. crate B). This allows us to
556 // treat the 'local' and 'foreign' cases almost identically during deserialization:
557 // we can call `imported_source_files` for the proper crate, and binary search
558 // through the returned slice using our span.
559 let imported_source_files = if tag == TAG_VALID_SPAN_LOCAL {
560 decoder.cdata().imported_source_files(sess)
562 // When we encode a proc-macro crate, all `Span`s should be encoded
563 // with `TAG_VALID_SPAN_LOCAL`
564 if decoder.cdata().root.is_proc_macro_crate() {
565 // Decode `CrateNum` as u32 - using `CrateNum::decode` will ICE
566 // since we don't have `cnum_map` populated.
567 let cnum = u32::decode(decoder);
569 "Decoding of crate {:?} tried to access proc-macro dep {:?}",
570 decoder.cdata().root.name,
574 // tag is TAG_VALID_SPAN_FOREIGN, checked by `debug_assert` above
575 let cnum = CrateNum::decode(decoder);
577 "SpecializedDecoder<Span>::specialized_decode: loading source files from cnum {:?}",
581 // Decoding 'foreign' spans should be rare enough that it's
582 // not worth it to maintain a per-CrateNum cache for `last_source_file_index`.
583 // We just set it to 0, to ensure that we don't try to access something out
584 // of bounds for our initial 'guess'
585 decoder.last_source_file_index = 0;
587 let foreign_data = decoder.cdata().cstore.get_crate_data(cnum);
588 foreign_data.imported_source_files(sess)
592 // Optimize for the case that most spans within a translated item
593 // originate from the same source_file.
594 let last_source_file = &imported_source_files[decoder.last_source_file_index];
596 if lo >= last_source_file.original_start_pos && lo <= last_source_file.original_end_pos
600 let index = imported_source_files
601 .binary_search_by_key(&lo, |source_file| source_file.original_start_pos)
602 .unwrap_or_else(|index| index - 1);
604 // Don't try to cache the index for foreign spans,
605 // as this would require a map from CrateNums to indices
606 if tag == TAG_VALID_SPAN_LOCAL {
607 decoder.last_source_file_index = index;
609 &imported_source_files[index]
613 // Make sure our binary search above is correct.
615 lo >= source_file.original_start_pos && lo <= source_file.original_end_pos,
616 "Bad binary search: lo={:?} source_file.original_start_pos={:?} source_file.original_end_pos={:?}",
618 source_file.original_start_pos,
619 source_file.original_end_pos
622 // Make sure we correctly filtered out invalid spans during encoding
624 hi >= source_file.original_start_pos && hi <= source_file.original_end_pos,
625 "Bad binary search: hi={:?} source_file.original_start_pos={:?} source_file.original_end_pos={:?}",
627 source_file.original_start_pos,
628 source_file.original_end_pos
632 (lo + source_file.translated_source_file.start_pos) - source_file.original_start_pos;
634 (hi + source_file.translated_source_file.start_pos) - source_file.original_start_pos;
636 // Do not try to decode parent for foreign spans.
637 Span::new(lo, hi, ctxt, None)
641 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for &'tcx [thir::abstract_const::Node<'tcx>] {
642 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Self {
643 ty::codec::RefDecodable::decode(d)
647 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for &'tcx [(ty::Predicate<'tcx>, Span)] {
648 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Self {
649 ty::codec::RefDecodable::decode(d)
653 impl<'a, 'tcx, T> Decodable<DecodeContext<'a, 'tcx>> for LazyValue<T> {
654 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self {
659 impl<'a, 'tcx, T> Decodable<DecodeContext<'a, 'tcx>> for LazyArray<T> {
660 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self {
661 let len = decoder.read_usize();
662 if len == 0 { LazyArray::empty() } else { decoder.read_lazy_array(len) }
666 impl<'a, 'tcx, I: Idx, T> Decodable<DecodeContext<'a, 'tcx>> for LazyTable<I, T> {
667 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self {
668 let len = decoder.read_usize();
669 decoder.read_lazy_table(len)
673 implement_ty_decoder!(DecodeContext<'a, 'tcx>);
676 pub(crate) fn new(metadata_ref: MetadataRef) -> MetadataBlob {
677 MetadataBlob(Lrc::new(metadata_ref))
680 pub(crate) fn is_compatible(&self) -> bool {
681 self.blob().starts_with(METADATA_HEADER)
684 pub(crate) fn get_rustc_version(&self) -> String {
685 LazyValue::<String>::from_position(NonZeroUsize::new(METADATA_HEADER.len() + 4).unwrap())
689 pub(crate) fn get_root(&self) -> CrateRoot {
690 let slice = &self.blob()[..];
691 let offset = METADATA_HEADER.len();
692 let pos = (((slice[offset + 0] as u32) << 24)
693 | ((slice[offset + 1] as u32) << 16)
694 | ((slice[offset + 2] as u32) << 8)
695 | ((slice[offset + 3] as u32) << 0)) as usize;
696 LazyValue::<CrateRoot>::from_position(NonZeroUsize::new(pos).unwrap()).decode(self)
699 pub(crate) fn list_crate_metadata(&self, out: &mut dyn io::Write) -> io::Result<()> {
700 let root = self.get_root();
701 writeln!(out, "Crate info:")?;
702 writeln!(out, "name {}{}", root.name, root.extra_filename)?;
703 writeln!(out, "hash {} stable_crate_id {:?}", root.hash, root.stable_crate_id)?;
704 writeln!(out, "proc_macro {:?}", root.proc_macro_data.is_some())?;
705 writeln!(out, "=External Dependencies=")?;
706 for (i, dep) in root.crate_deps.decode(self).enumerate() {
709 "{} {}{} hash {} host_hash {:?} kind {:?}",
724 pub(crate) fn is_proc_macro_crate(&self) -> bool {
725 self.proc_macro_data.is_some()
728 pub(crate) fn name(&self) -> Symbol {
732 pub(crate) fn hash(&self) -> Svh {
736 pub(crate) fn stable_crate_id(&self) -> StableCrateId {
740 pub(crate) fn triple(&self) -> &TargetTriple {
744 pub(crate) fn decode_crate_deps<'a>(
746 metadata: &'a MetadataBlob,
747 ) -> impl ExactSizeIterator<Item = CrateDep> + Captures<'a> {
748 self.crate_deps.decode(metadata)
752 impl<'a, 'tcx> CrateMetadataRef<'a> {
753 fn raw_proc_macro(self, id: DefIndex) -> &'a ProcMacro {
754 // DefIndex's in root.proc_macro_data have a one-to-one correspondence
755 // with items in 'raw_proc_macros'.
763 .position(|i| i == id)
765 &self.raw_proc_macros.unwrap()[pos]
768 fn opt_item_name(self, item_index: DefIndex) -> Option<Symbol> {
769 self.def_key(item_index).disambiguated_data.data.get_opt_name()
772 fn item_name(self, item_index: DefIndex) -> Symbol {
773 self.opt_item_name(item_index).expect("no encoded ident for item")
776 fn opt_item_ident(self, item_index: DefIndex, sess: &Session) -> Option<Ident> {
777 let name = self.opt_item_name(item_index)?;
778 let span = match self.root.tables.def_ident_span.get(self, item_index) {
779 Some(lazy_span) => lazy_span.decode((self, sess)),
781 // FIXME: this weird case of a name with no span is specific to `extern crate`
782 // items, which are supposed to be treated like `use` items and only be encoded
783 // to metadata as `Export`s, return `None` because that's what all the callers
784 // expect in this case.
785 assert_eq!(self.def_kind(item_index), DefKind::ExternCrate);
789 Some(Ident::new(name, span))
792 fn item_ident(self, item_index: DefIndex, sess: &Session) -> Ident {
793 self.opt_item_ident(item_index, sess).expect("no encoded ident for item")
796 fn maybe_kind(self, item_id: DefIndex) -> Option<EntryKind> {
797 self.root.tables.kind.get(self, item_id).map(|k| k.decode(self))
801 pub(super) fn map_encoded_cnum_to_current(self, cnum: CrateNum) -> CrateNum {
802 if cnum == LOCAL_CRATE { self.cnum } else { self.cnum_map[cnum] }
805 fn kind(self, item_id: DefIndex) -> EntryKind {
806 self.maybe_kind(item_id).unwrap_or_else(|| {
808 "CrateMetadata::kind({:?}): id not found, in crate {:?} with number {}",
816 fn def_kind(self, item_id: DefIndex) -> DefKind {
817 self.root.tables.opt_def_kind.get(self, item_id).unwrap_or_else(|| {
819 "CrateMetadata::def_kind({:?}): id not found, in crate {:?} with number {}",
827 fn get_span(self, index: DefIndex, sess: &Session) -> Span {
832 .unwrap_or_else(|| panic!("Missing span for {:?}", index))
833 .decode((self, sess))
836 fn load_proc_macro(self, id: DefIndex, sess: &Session) -> SyntaxExtension {
837 let (name, kind, helper_attrs) = match *self.raw_proc_macro(id) {
838 ProcMacro::CustomDerive { trait_name, attributes, client } => {
840 attributes.iter().cloned().map(Symbol::intern).collect::<Vec<_>>();
843 SyntaxExtensionKind::Derive(Box::new(DeriveProcMacro { client })),
847 ProcMacro::Attr { name, client } => {
848 (name, SyntaxExtensionKind::Attr(Box::new(AttrProcMacro { client })), Vec::new())
850 ProcMacro::Bang { name, client } => {
851 (name, SyntaxExtensionKind::Bang(Box::new(BangProcMacro { client })), Vec::new())
855 let attrs: Vec<_> = self.get_item_attrs(id, sess).collect();
856 SyntaxExtension::new(
859 self.get_span(id, sess),
862 Symbol::intern(name),
867 fn get_variant(self, kind: &EntryKind, index: DefIndex, parent_did: DefId) -> ty::VariantDef {
868 let data = match kind {
869 EntryKind::Variant(data) | EntryKind::Struct(data) | EntryKind::Union(data) => {
875 let adt_kind = match kind {
876 EntryKind::Variant(_) => ty::AdtKind::Enum,
877 EntryKind::Struct(..) => ty::AdtKind::Struct,
878 EntryKind::Union(..) => ty::AdtKind::Union,
883 if adt_kind == ty::AdtKind::Enum { Some(self.local_def_id(index)) } else { None };
884 let ctor_did = data.ctor.map(|index| self.local_def_id(index));
887 self.item_name(index),
895 .unwrap_or_else(LazyArray::empty)
897 .map(|index| ty::FieldDef {
898 did: self.local_def_id(index),
899 name: self.item_name(index),
900 vis: self.get_visibility(index),
907 data.is_non_exhaustive,
911 fn get_adt_def(self, item_id: DefIndex, tcx: TyCtxt<'tcx>) -> ty::AdtDef<'tcx> {
912 let kind = self.kind(item_id);
913 let did = self.local_def_id(item_id);
915 let adt_kind = match kind {
916 EntryKind::Enum => ty::AdtKind::Enum,
917 EntryKind::Struct(_) => ty::AdtKind::Struct,
918 EntryKind::Union(_) => ty::AdtKind::Union,
919 _ => bug!("get_adt_def called on a non-ADT {:?}", did),
921 let repr = self.root.tables.repr_options.get(self, item_id).unwrap().decode(self);
923 let variants = if let ty::AdtKind::Enum = adt_kind {
928 .unwrap_or_else(LazyArray::empty)
930 .map(|index| self.get_variant(&self.kind(index), index, did))
933 std::iter::once(self.get_variant(&kind, item_id, did)).collect()
936 tcx.alloc_adt_def(did, adt_kind, variants, repr)
939 fn get_generics(self, item_id: DefIndex, sess: &Session) -> ty::Generics {
940 self.root.tables.generics_of.get(self, item_id).unwrap().decode((self, sess))
943 fn get_visibility(self, id: DefIndex) -> ty::Visibility {
944 self.root.tables.visibility.get(self, id).unwrap().decode(self)
947 fn get_trait_item_def_id(self, id: DefIndex) -> Option<DefId> {
948 self.root.tables.trait_item_def_id.get(self, id).map(|d| d.decode_from_cdata(self))
951 fn get_expn_that_defined(self, id: DefIndex, sess: &Session) -> ExpnId {
952 self.root.tables.expn_that_defined.get(self, id).unwrap().decode((self, sess))
955 fn get_debugger_visualizers(self) -> Vec<rustc_span::DebuggerVisualizerFile> {
956 self.root.debugger_visualizers.decode(self).collect::<Vec<_>>()
959 /// Iterates over all the stability attributes in the given crate.
960 fn get_lib_features(self, tcx: TyCtxt<'tcx>) -> &'tcx [(Symbol, Option<Symbol>)] {
961 tcx.arena.alloc_from_iter(self.root.lib_features.decode(self))
964 /// Iterates over the language items in the given crate.
965 fn get_lang_items(self, tcx: TyCtxt<'tcx>) -> &'tcx [(DefId, usize)] {
966 tcx.arena.alloc_from_iter(
970 .map(move |(def_index, index)| (self.local_def_id(def_index), index)),
974 /// Iterates over the diagnostic items in the given crate.
975 fn get_diagnostic_items(self) -> DiagnosticItems {
976 let mut id_to_name = FxHashMap::default();
977 let name_to_id = self
981 .map(|(name, def_index)| {
982 let id = self.local_def_id(def_index);
983 id_to_name.insert(id, name);
987 DiagnosticItems { id_to_name, name_to_id }
990 /// Iterates over all named children of the given module,
991 /// including both proper items and reexports.
992 /// Module here is understood in name resolution sense - it can be a `mod` item,
993 /// or a crate root, or an enum, or a trait.
994 fn for_each_module_child(
997 mut callback: impl FnMut(ModChild),
1000 if let Some(data) = &self.root.proc_macro_data {
1001 // If we are loading as a proc macro, we want to return
1002 // the view of this crate as a proc macro crate.
1003 if id == CRATE_DEF_INDEX {
1004 for def_index in data.macros.decode(self) {
1005 let raw_macro = self.raw_proc_macro(def_index);
1007 DefKind::Macro(macro_kind(raw_macro)),
1008 self.local_def_id(def_index),
1010 let ident = self.item_ident(def_index, sess);
1014 vis: ty::Visibility::Public,
1023 // Iterate over all children.
1024 if let Some(children) = self.root.tables.children.get(self, id) {
1025 for child_index in children.decode((self, sess)) {
1026 let ident = self.item_ident(child_index, sess);
1027 let kind = self.def_kind(child_index);
1028 let def_id = self.local_def_id(child_index);
1029 let res = Res::Def(kind, def_id);
1030 let vis = self.get_visibility(child_index);
1031 let span = self.get_span(child_index, sess);
1032 let macro_rules = match kind {
1033 DefKind::Macro(..) => match self.kind(child_index) {
1034 EntryKind::MacroDef(_, macro_rules) => macro_rules,
1035 _ => unreachable!(),
1040 callback(ModChild { ident, res, vis, span, macro_rules });
1042 // For non-re-export structs and variants add their constructors to children.
1043 // Re-export lists automatically contain constructors when necessary.
1045 DefKind::Struct => {
1046 if let Some((ctor_def_id, ctor_kind)) =
1047 self.get_ctor_def_id_and_kind(child_index)
1050 Res::Def(DefKind::Ctor(CtorOf::Struct, ctor_kind), ctor_def_id);
1051 let vis = self.get_visibility(ctor_def_id.index);
1061 DefKind::Variant => {
1062 // Braced variants, unlike structs, generate unusable names in
1063 // value namespace, they are reserved for possible future use.
1064 // It's ok to use the variant's id as a ctor id since an
1065 // error will be reported on any use of such resolution anyway.
1066 let (ctor_def_id, ctor_kind) = self
1067 .get_ctor_def_id_and_kind(child_index)
1068 .unwrap_or((def_id, CtorKind::Fictive));
1070 Res::Def(DefKind::Ctor(CtorOf::Variant, ctor_kind), ctor_def_id);
1071 let mut vis = self.get_visibility(ctor_def_id.index);
1072 if ctor_def_id == def_id && vis.is_public() {
1073 // For non-exhaustive variants lower the constructor visibility to
1074 // within the crate. We only need this for fictive constructors,
1075 // for other constructors correct visibilities
1076 // were already encoded in metadata.
1077 let mut attrs = self.get_item_attrs(def_id.index, sess);
1078 if attrs.any(|item| item.has_name(sym::non_exhaustive)) {
1079 let crate_def_id = self.local_def_id(CRATE_DEF_INDEX);
1080 vis = ty::Visibility::Restricted(crate_def_id);
1083 callback(ModChild { ident, res: ctor_res, vis, span, macro_rules: false });
1090 match self.kind(id) {
1091 EntryKind::Mod(exports) => {
1092 for exp in exports.decode((self, sess)) {
1096 EntryKind::Enum | EntryKind::Trait => {}
1097 _ => bug!("`for_each_module_child` is called on a non-module: {:?}", self.def_kind(id)),
1101 fn is_ctfe_mir_available(self, id: DefIndex) -> bool {
1102 self.root.tables.mir_for_ctfe.get(self, id).is_some()
1105 fn is_item_mir_available(self, id: DefIndex) -> bool {
1106 self.root.tables.optimized_mir.get(self, id).is_some()
1109 fn module_expansion(self, id: DefIndex, sess: &Session) -> ExpnId {
1110 match self.kind(id) {
1111 EntryKind::Mod(_) | EntryKind::Enum | EntryKind::Trait => {
1112 self.get_expn_that_defined(id, sess)
1114 _ => panic!("Expected module, found {:?}", self.local_def_id(id)),
1118 fn get_fn_has_self_parameter(self, id: DefIndex) -> bool {
1119 match self.kind(id) {
1120 EntryKind::AssocFn(data) => data.decode(self).has_self,
1125 fn get_associated_item_def_ids(
1129 ) -> impl Iterator<Item = DefId> + 'a {
1134 .unwrap_or_else(LazyArray::empty)
1135 .decode((self, sess))
1136 .map(move |child_index| self.local_def_id(child_index))
1139 fn get_associated_item(self, id: DefIndex) -> ty::AssocItem {
1140 let def_key = self.def_key(id);
1141 let parent = self.local_def_id(def_key.parent.unwrap());
1142 let name = self.item_name(id);
1144 let (kind, container, has_self) = match self.kind(id) {
1145 EntryKind::AssocConst(container) => (ty::AssocKind::Const, container, false),
1146 EntryKind::AssocFn(data) => {
1147 let data = data.decode(self);
1148 (ty::AssocKind::Fn, data.container, data.has_self)
1150 EntryKind::AssocType(container) => (ty::AssocKind::Type, container, false),
1151 _ => bug!("cannot get associated-item of `{:?}`", def_key),
1157 vis: self.get_visibility(id),
1158 defaultness: container.defaultness(),
1159 def_id: self.local_def_id(id),
1160 trait_item_def_id: self.get_trait_item_def_id(id),
1161 container: container.with_def_id(parent),
1162 fn_has_self_parameter: has_self,
1166 fn get_ctor_def_id_and_kind(self, node_id: DefIndex) -> Option<(DefId, CtorKind)> {
1167 match self.kind(node_id) {
1168 EntryKind::Struct(data) | EntryKind::Variant(data) => {
1169 let vdata = data.decode(self);
1170 vdata.ctor.map(|index| (self.local_def_id(index), vdata.ctor_kind))
1180 ) -> impl Iterator<Item = ast::Attribute> + 'a {
1185 .unwrap_or_else(|| {
1186 // Structure and variant constructors don't have any attributes encoded for them,
1187 // but we assume that someone passing a constructor ID actually wants to look at
1188 // the attributes on the corresponding struct or variant.
1189 let def_key = self.def_key(id);
1190 assert_eq!(def_key.disambiguated_data.data, DefPathData::Ctor);
1191 let parent_id = def_key.parent.expect("no parent for a constructor");
1195 .get(self, parent_id)
1196 .expect("no encoded attributes for a structure or variant")
1198 .decode((self, sess))
1201 fn get_struct_field_names(
1205 ) -> impl Iterator<Item = Spanned<Symbol>> + 'a {
1210 .unwrap_or_else(LazyArray::empty)
1212 .map(move |index| respan(self.get_span(index, sess), self.item_name(index)))
1215 fn get_struct_field_visibilities(self, id: DefIndex) -> impl Iterator<Item = Visibility> + 'a {
1220 .unwrap_or_else(LazyArray::empty)
1222 .map(move |field_index| self.get_visibility(field_index))
1225 fn get_inherent_implementations_for_type(
1229 ) -> &'tcx [DefId] {
1230 tcx.arena.alloc_from_iter(
1235 .unwrap_or_else(LazyArray::empty)
1237 .map(|index| self.local_def_id(index)),
1241 /// Decodes all inherent impls in the crate (for rustdoc).
1242 fn get_inherent_impls(self) -> impl Iterator<Item = (DefId, DefId)> + 'a {
1243 (0..self.root.tables.inherent_impls.size()).flat_map(move |i| {
1244 let ty_index = DefIndex::from_usize(i);
1245 let ty_def_id = self.local_def_id(ty_index);
1249 .get(self, ty_index)
1250 .unwrap_or_else(LazyArray::empty)
1252 .map(move |impl_index| (ty_def_id, self.local_def_id(impl_index)))
1256 /// Decodes all traits in the crate (for rustdoc and rustc diagnostics).
1257 fn get_traits(self) -> impl Iterator<Item = DefId> + 'a {
1258 self.root.traits.decode(self).map(move |index| self.local_def_id(index))
1261 /// Decodes all trait impls in the crate (for rustdoc).
1262 fn get_trait_impls(self) -> impl Iterator<Item = (DefId, DefId, Option<SimplifiedType>)> + 'a {
1263 self.cdata.trait_impls.iter().flat_map(move |(&(trait_cnum_raw, trait_index), impls)| {
1264 let trait_def_id = DefId {
1265 krate: self.cnum_map[CrateNum::from_u32(trait_cnum_raw)],
1268 impls.decode(self).map(move |(impl_index, simplified_self_ty)| {
1269 (trait_def_id, self.local_def_id(impl_index), simplified_self_ty)
1274 fn get_all_incoherent_impls(self) -> impl Iterator<Item = DefId> + 'a {
1278 .flat_map(move |impls| impls.decode(self).map(move |idx| self.local_def_id(idx)))
1281 fn get_incoherent_impls(self, tcx: TyCtxt<'tcx>, simp: SimplifiedType) -> &'tcx [DefId] {
1282 if let Some(impls) = self.cdata.incoherent_impls.get(&simp) {
1283 tcx.arena.alloc_from_iter(impls.decode(self).map(|idx| self.local_def_id(idx)))
1289 fn get_implementations_of_trait(
1292 trait_def_id: DefId,
1293 ) -> &'tcx [(DefId, Option<SimplifiedType>)] {
1294 if self.trait_impls.is_empty() {
1298 // Do a reverse lookup beforehand to avoid touching the crate_num
1299 // hash map in the loop below.
1300 let key = match self.reverse_translate_def_id(trait_def_id) {
1301 Some(def_id) => (def_id.krate.as_u32(), def_id.index),
1305 if let Some(impls) = self.trait_impls.get(&key) {
1306 tcx.arena.alloc_from_iter(
1309 .map(|(idx, simplified_self_ty)| (self.local_def_id(idx), simplified_self_ty)),
1316 fn get_trait_of_item(self, id: DefIndex) -> Option<DefId> {
1317 let def_key = self.def_key(id);
1318 match def_key.disambiguated_data.data {
1319 DefPathData::TypeNs(..) | DefPathData::ValueNs(..) => (),
1320 // Not an associated item
1323 def_key.parent.and_then(|parent_index| match self.kind(parent_index) {
1324 EntryKind::Trait | EntryKind::TraitAlias => Some(self.local_def_id(parent_index)),
1329 fn get_native_libraries(self, sess: &'a Session) -> impl Iterator<Item = NativeLib> + 'a {
1330 self.root.native_libraries.decode((self, sess))
1333 fn get_proc_macro_quoted_span(self, index: usize, sess: &Session) -> Span {
1336 .proc_macro_quoted_spans
1338 .unwrap_or_else(|| panic!("Missing proc macro quoted span: {:?}", index))
1339 .decode((self, sess))
1342 fn get_foreign_modules(self, sess: &'a Session) -> impl Iterator<Item = ForeignModule> + '_ {
1343 self.root.foreign_modules.decode((self, sess))
1346 fn get_dylib_dependency_formats(
1349 ) -> &'tcx [(CrateNum, LinkagePreference)] {
1350 tcx.arena.alloc_from_iter(
1351 self.root.dylib_dependency_formats.decode(self).enumerate().flat_map(|(i, link)| {
1352 let cnum = CrateNum::new(i + 1);
1353 link.map(|link| (self.cnum_map[cnum], link))
1358 fn get_missing_lang_items(self, tcx: TyCtxt<'tcx>) -> &'tcx [lang_items::LangItem] {
1359 tcx.arena.alloc_from_iter(self.root.lang_items_missing.decode(self))
1362 fn exported_symbols(
1365 ) -> &'tcx [(ExportedSymbol<'tcx>, SymbolExportInfo)] {
1366 tcx.arena.alloc_from_iter(self.root.exported_symbols.decode((self, tcx)))
1369 fn get_macro(self, id: DefIndex, sess: &Session) -> ast::MacroDef {
1370 match self.kind(id) {
1371 EntryKind::MacroDef(mac_args, macro_rules) => {
1372 ast::MacroDef { body: P(mac_args.decode((self, sess))), macro_rules }
1378 fn is_foreign_item(self, id: DefIndex) -> bool {
1379 match self.kind(id) {
1380 EntryKind::ForeignStatic | EntryKind::ForeignFn => true,
1386 fn def_key(self, index: DefIndex) -> DefKey {
1391 .or_insert_with(|| self.root.tables.def_keys.get(self, index).unwrap().decode(self))
1394 // Returns the path leading to the thing with this `id`.
1395 fn def_path(self, id: DefIndex) -> DefPath {
1396 debug!("def_path(cnum={:?}, id={:?})", self.cnum, id);
1397 DefPath::make(self.cnum, id, |parent| self.def_key(parent))
1400 fn def_path_hash_unlocked(
1403 def_path_hashes: &mut FxHashMap<DefIndex, DefPathHash>,
1407 .or_insert_with(|| self.root.tables.def_path_hashes.get(self, index).unwrap())
1411 fn def_path_hash(self, index: DefIndex) -> DefPathHash {
1412 let mut def_path_hashes = self.def_path_hash_cache.lock();
1413 self.def_path_hash_unlocked(index, &mut def_path_hashes)
1417 fn def_path_hash_to_def_index(self, hash: DefPathHash) -> DefIndex {
1418 self.def_path_hash_map.def_path_hash_to_def_index(&hash)
1421 fn expn_hash_to_expn_id(self, sess: &Session, index_guess: u32, hash: ExpnHash) -> ExpnId {
1422 debug_assert_eq!(ExpnId::from_hash(hash), None);
1423 let index_guess = ExpnIndex::from_u32(index_guess);
1424 let old_hash = self.root.expn_hashes.get(self, index_guess).map(|lazy| lazy.decode(self));
1426 let index = if old_hash == Some(hash) {
1427 // Fast path: the expn and its index is unchanged from the
1428 // previous compilation session. There is no need to decode anything
1432 // Slow path: We need to find out the new `DefIndex` of the provided
1433 // `DefPathHash`, if its still exists. This requires decoding every `DefPathHash`
1434 // stored in this crate.
1435 let map = self.cdata.expn_hash_map.get_or_init(|| {
1436 let end_id = self.root.expn_hashes.size() as u32;
1438 UnhashMap::with_capacity_and_hasher(end_id as usize, Default::default());
1439 for i in 0..end_id {
1440 let i = ExpnIndex::from_u32(i);
1441 if let Some(hash) = self.root.expn_hashes.get(self, i) {
1442 map.insert(hash.decode(self), i);
1450 let data = self.root.expn_data.get(self, index).unwrap().decode((self, sess));
1451 rustc_span::hygiene::register_expn_id(self.cnum, index, data, hash)
1454 /// Imports the source_map from an external crate into the source_map of the crate
1455 /// currently being compiled (the "local crate").
1457 /// The import algorithm works analogous to how AST items are inlined from an
1458 /// external crate's metadata:
1459 /// For every SourceFile in the external source_map an 'inline' copy is created in the
1460 /// local source_map. The correspondence relation between external and local
1461 /// SourceFiles is recorded in the `ImportedSourceFile` objects returned from this
1462 /// function. When an item from an external crate is later inlined into this
1463 /// crate, this correspondence information is used to translate the span
1464 /// information of the inlined item so that it refers the correct positions in
1465 /// the local source_map (see `<decoder::DecodeContext as SpecializedDecoder<Span>>`).
1467 /// The import algorithm in the function below will reuse SourceFiles already
1468 /// existing in the local source_map. For example, even if the SourceFile of some
1469 /// source file of libstd gets imported many times, there will only ever be
1470 /// one SourceFile object for the corresponding file in the local source_map.
1472 /// Note that imported SourceFiles do not actually contain the source code of the
1473 /// file they represent, just information about length, line breaks, and
1474 /// multibyte characters. This information is enough to generate valid debuginfo
1475 /// for items inlined from other crates.
1477 /// Proc macro crates don't currently export spans, so this function does not have
1478 /// to work for them.
1479 fn imported_source_files(self, sess: &Session) -> &'a [ImportedSourceFile] {
1480 // Translate the virtual `/rustc/$hash` prefix back to a real directory
1481 // that should hold actual sources, where possible.
1483 // NOTE: if you update this, you might need to also update bootstrap's code for generating
1484 // the `rust-src` component in `Src::run` in `src/bootstrap/dist.rs`.
1485 let virtual_rust_source_base_dir = option_env!("CFG_VIRTUAL_RUST_SOURCE_BASE_DIR")
1488 // Only spend time on further checks if we have what to translate *to*.
1489 sess.opts.real_rust_source_base_dir.is_some()
1491 .filter(|virtual_dir| {
1492 // Don't translate away `/rustc/$hash` if we're still remapping to it,
1493 // since that means we're still building `std`/`rustc` that need it,
1494 // and we don't want the real path to leak into codegen/debuginfo.
1495 !sess.opts.remap_path_prefix.iter().any(|(_from, to)| to == virtual_dir)
1497 let try_to_translate_virtual_to_real = |name: &mut rustc_span::FileName| {
1499 "try_to_translate_virtual_to_real(name={:?}): \
1500 virtual_rust_source_base_dir={:?}, real_rust_source_base_dir={:?}",
1501 name, virtual_rust_source_base_dir, sess.opts.real_rust_source_base_dir,
1504 if let Some(virtual_dir) = virtual_rust_source_base_dir {
1505 if let Some(real_dir) = &sess.opts.real_rust_source_base_dir {
1506 if let rustc_span::FileName::Real(old_name) = name {
1507 if let rustc_span::RealFileName::Remapped { local_path: _, virtual_name } =
1510 if let Ok(rest) = virtual_name.strip_prefix(virtual_dir) {
1511 let virtual_name = virtual_name.clone();
1513 // The std library crates are in
1514 // `$sysroot/lib/rustlib/src/rust/library`, whereas other crates
1515 // may be in `$sysroot/lib/rustlib/src/rust/` directly. So we
1516 // detect crates from the std libs and handle them specially.
1517 const STD_LIBS: &[&str] = &[
1527 "profiler_builtins",
1529 "rustc-std-workspace-core",
1530 "rustc-std-workspace-alloc",
1531 "rustc-std-workspace-std",
1534 let is_std_lib = STD_LIBS.iter().any(|l| rest.starts_with(l));
1536 let new_path = if is_std_lib {
1537 real_dir.join("library").join(rest)
1543 "try_to_translate_virtual_to_real: `{}` -> `{}`",
1544 virtual_name.display(),
1547 let new_name = rustc_span::RealFileName::Remapped {
1548 local_path: Some(new_path),
1551 *old_name = new_name;
1559 self.cdata.source_map_import_info.get_or_init(|| {
1560 let external_source_map = self.root.source_map.decode(self);
1563 .map(|source_file_to_import| {
1564 // We can't reuse an existing SourceFile, so allocate a new one
1565 // containing the information we need.
1566 let rustc_span::SourceFile {
1577 } = source_file_to_import;
1579 // If this file is under $sysroot/lib/rustlib/src/ but has not been remapped
1580 // during rust bootstrapping by `remap-debuginfo = true`, and the user
1581 // wish to simulate that behaviour by -Z simulate-remapped-rust-src-base,
1582 // then we change `name` to a similar state as if the rust was bootstrapped
1583 // with `remap-debuginfo = true`.
1584 // This is useful for testing so that tests about the effects of
1585 // `try_to_translate_virtual_to_real` don't have to worry about how the
1586 // compiler is bootstrapped.
1587 if let Some(virtual_dir) =
1588 &sess.opts.debugging_opts.simulate_remapped_rust_src_base
1590 if let Some(real_dir) = &sess.opts.real_rust_source_base_dir {
1591 if let rustc_span::FileName::Real(ref mut old_name) = name {
1592 if let rustc_span::RealFileName::LocalPath(local) = old_name {
1593 if let Ok(rest) = local.strip_prefix(real_dir) {
1594 *old_name = rustc_span::RealFileName::Remapped {
1596 virtual_name: virtual_dir.join(rest),
1604 // If this file's path has been remapped to `/rustc/$hash`,
1605 // we might be able to reverse that (also see comments above,
1606 // on `try_to_translate_virtual_to_real`).
1607 try_to_translate_virtual_to_real(&mut name);
1609 let source_length = (end_pos - start_pos).to_usize();
1611 let local_version = sess.source_map().new_imported_source_file(
1625 "CrateMetaData::imported_source_files alloc \
1626 source_file {:?} original (start_pos {:?} end_pos {:?}) \
1627 translated (start_pos {:?} end_pos {:?})",
1631 local_version.start_pos,
1632 local_version.end_pos
1635 ImportedSourceFile {
1636 original_start_pos: start_pos,
1637 original_end_pos: end_pos,
1638 translated_source_file: local_version,
1645 fn get_generator_diagnostic_data(
1649 ) -> Option<GeneratorDiagnosticData<'tcx>> {
1652 .generator_diagnostic_data
1654 .map(|param| param.decode((self, tcx)))
1655 .map(|generator_data| GeneratorDiagnosticData {
1656 generator_interior_types: generator_data.generator_interior_types,
1657 hir_owner: generator_data.hir_owner,
1658 nodes_types: generator_data.nodes_types,
1659 adjustments: generator_data.adjustments,
1663 fn get_may_have_doc_links(self, index: DefIndex) -> bool {
1664 self.root.tables.may_have_doc_links.get(self, index).is_some()
1667 fn get_is_intrinsic(self, index: DefIndex) -> bool {
1668 self.root.tables.is_intrinsic.get(self, index).is_some()
1672 impl CrateMetadata {
1678 raw_proc_macros: Option<&'static [ProcMacro]>,
1680 cnum_map: CrateNumMap,
1681 dep_kind: CrateDepKind,
1682 source: CrateSource,
1684 host_hash: Option<Svh>,
1685 ) -> CrateMetadata {
1686 let trait_impls = root
1688 .decode((&blob, sess))
1689 .map(|trait_impls| (trait_impls.trait_id, trait_impls.impls))
1691 let alloc_decoding_state =
1692 AllocDecodingState::new(root.interpret_alloc_index.decode(&blob).collect());
1693 let dependencies = Lock::new(cnum_map.iter().cloned().collect());
1695 // Pre-decode the DefPathHash->DefIndex table. This is a cheap operation
1696 // that does not copy any data. It just does some data verification.
1697 let def_path_hash_map = root.def_path_hash_map.decode(&blob);
1699 let mut cdata = CrateMetadata {
1703 incoherent_impls: Default::default(),
1705 source_map_import_info: OnceCell::new(),
1707 expn_hash_map: Default::default(),
1708 alloc_decoding_state,
1712 dep_kind: Lock::new(dep_kind),
1713 source: Lrc::new(source),
1716 extern_crate: Lock::new(None),
1717 hygiene_context: Default::default(),
1718 def_key_cache: Default::default(),
1719 def_path_hash_cache: Default::default(),
1722 // Need `CrateMetadataRef` to decode `DefId`s in simplified types.
1723 cdata.incoherent_impls = cdata
1726 .decode(CrateMetadataRef { cdata: &cdata, cstore })
1727 .map(|incoherent_impls| (incoherent_impls.self_ty, incoherent_impls.impls))
1733 pub(crate) fn dependencies(&self) -> LockGuard<'_, Vec<CrateNum>> {
1734 self.dependencies.borrow()
1737 pub(crate) fn add_dependency(&self, cnum: CrateNum) {
1738 self.dependencies.borrow_mut().push(cnum);
1741 pub(crate) fn update_extern_crate(&self, new_extern_crate: ExternCrate) -> bool {
1742 let mut extern_crate = self.extern_crate.borrow_mut();
1743 let update = Some(new_extern_crate.rank()) > extern_crate.as_ref().map(ExternCrate::rank);
1745 *extern_crate = Some(new_extern_crate);
1750 pub(crate) fn source(&self) -> &CrateSource {
1754 pub(crate) fn dep_kind(&self) -> CrateDepKind {
1755 *self.dep_kind.lock()
1758 pub(crate) fn update_dep_kind(&self, f: impl FnOnce(CrateDepKind) -> CrateDepKind) {
1759 self.dep_kind.with_lock(|dep_kind| *dep_kind = f(*dep_kind))
1762 pub(crate) fn panic_strategy(&self) -> PanicStrategy {
1763 self.root.panic_strategy
1766 pub(crate) fn needs_panic_runtime(&self) -> bool {
1767 self.root.needs_panic_runtime
1770 pub(crate) fn is_panic_runtime(&self) -> bool {
1771 self.root.panic_runtime
1774 pub(crate) fn is_profiler_runtime(&self) -> bool {
1775 self.root.profiler_runtime
1778 pub(crate) fn needs_allocator(&self) -> bool {
1779 self.root.needs_allocator
1782 pub(crate) fn has_global_allocator(&self) -> bool {
1783 self.root.has_global_allocator
1786 pub(crate) fn has_default_lib_allocator(&self) -> bool {
1787 self.root.has_default_lib_allocator
1790 pub(crate) fn is_proc_macro_crate(&self) -> bool {
1791 self.root.is_proc_macro_crate()
1794 pub(crate) fn name(&self) -> Symbol {
1798 pub(crate) fn stable_crate_id(&self) -> StableCrateId {
1799 self.root.stable_crate_id
1802 pub(crate) fn hash(&self) -> Svh {
1806 fn num_def_ids(&self) -> usize {
1807 self.root.tables.def_keys.size()
1810 fn local_def_id(&self, index: DefIndex) -> DefId {
1811 DefId { krate: self.cnum, index }
1814 // Translate a DefId from the current compilation environment to a DefId
1815 // for an external crate.
1816 fn reverse_translate_def_id(&self, did: DefId) -> Option<DefId> {
1817 for (local, &global) in self.cnum_map.iter_enumerated() {
1818 if global == did.krate {
1819 return Some(DefId { krate: local, index: did.index });
1827 // Cannot be implemented on 'ProcMacro', as libproc_macro
1828 // does not depend on librustc_ast
1829 fn macro_kind(raw: &ProcMacro) -> MacroKind {
1831 ProcMacro::CustomDerive { .. } => MacroKind::Derive,
1832 ProcMacro::Attr { .. } => MacroKind::Attr,
1833 ProcMacro::Bang { .. } => MacroKind::Bang,