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;
46 pub(super) use cstore_impl::provide;
47 pub use cstore_impl::provide_extern;
48 use rustc_span::hygiene::HygieneDecodeContext;
52 /// A reference to the raw binary version of crate metadata.
53 /// A `MetadataBlob` internally is just a reference counted pointer to
54 /// the actual data, so cloning it is cheap.
56 pub(crate) struct MetadataBlob(Lrc<MetadataRef>);
58 // This is needed so we can create an OwningRef into the blob.
59 // The data behind a `MetadataBlob` has a stable address because it is
60 // contained within an Rc/Arc.
61 unsafe impl rustc_data_structures::owning_ref::StableAddress for MetadataBlob {}
63 // This is needed so we can create an OwningRef into the blob.
64 impl std::ops::Deref for MetadataBlob {
68 fn deref(&self) -> &[u8] {
73 // A map from external crate numbers (as decoded from some crate file) to
74 // local crate numbers (as generated during this session). Each external
75 // crate may refer to types in other external crates, and each has their
77 pub(crate) type CrateNumMap = IndexVec<CrateNum, CrateNum>;
79 pub(crate) struct CrateMetadata {
80 /// The primary crate data - binary metadata blob.
83 // --- Some data pre-decoded from the metadata blob, usually for performance ---
84 /// NOTE(eddyb) we pass `'static` to a `'tcx` parameter because this
85 /// lifetime is only used behind `LazyValue`, `LazyArray`, or `LazyTable`, and therefore acts like a
86 /// universal (`for<'tcx>`), that is paired up with whichever `TyCtxt`
87 /// is being used to decode those values.
90 /// FIXME: Used only from queries and can use query cache,
91 /// so pre-decoding can probably be avoided.
92 trait_impls: FxHashMap<(u32, DefIndex), LazyArray<(DefIndex, Option<SimplifiedType>)>>,
93 /// Inherent impls which do not follow the normal coherence rules.
95 /// These can be introduced using either `#![rustc_coherence_is_core]`
96 /// or `#[rustc_allow_incoherent_impl]`.
97 incoherent_impls: FxHashMap<SimplifiedType, LazyArray<DefIndex>>,
98 /// Proc macro descriptions for this crate, if it's a proc macro crate.
99 raw_proc_macros: Option<&'static [ProcMacro]>,
100 /// Source maps for code from the crate.
101 source_map_import_info: Lock<Vec<Option<ImportedSourceFile>>>,
102 /// For every definition in this crate, maps its `DefPathHash` to its `DefIndex`.
103 def_path_hash_map: DefPathHashMapRef<'static>,
104 /// Likewise for ExpnHash.
105 expn_hash_map: OnceCell<UnhashMap<ExpnHash, ExpnIndex>>,
106 /// Used for decoding interpret::AllocIds in a cached & thread-safe manner.
107 alloc_decoding_state: AllocDecodingState,
108 /// Caches decoded `DefKey`s.
109 def_key_cache: Lock<FxHashMap<DefIndex, DefKey>>,
110 /// Caches decoded `DefPathHash`es.
111 def_path_hash_cache: Lock<FxHashMap<DefIndex, DefPathHash>>,
113 // --- Other significant crate properties ---
114 /// ID of this crate, from the current compilation session's point of view.
116 /// Maps crate IDs as they are were seen from this crate's compilation sessions into
117 /// IDs as they are seen from the current compilation session.
118 cnum_map: CrateNumMap,
119 /// Same ID set as `cnum_map` plus maybe some injected crates like panic runtime.
120 dependencies: Lock<Vec<CrateNum>>,
121 /// How to link (or not link) this crate to the currently compiled crate.
122 dep_kind: Lock<CrateDepKind>,
123 /// Filesystem location of this crate.
124 source: Lrc<CrateSource>,
125 /// Whether or not this crate should be consider a private dependency
126 /// for purposes of the 'exported_private_dependencies' lint
128 /// The hash for the host proc macro. Used to support `-Z dual-proc-macro`.
129 host_hash: Option<Svh>,
131 /// Additional data used for decoding `HygieneData` (e.g. `SyntaxContext`
133 /// Note that we store a `HygieneDecodeContext` for each `CrateMetadat`. This is
134 /// because `SyntaxContext` ids are not globally unique, so we need
135 /// to track which ids we've decoded on a per-crate basis.
136 hygiene_context: HygieneDecodeContext,
138 // --- Data used only for improving diagnostics ---
139 /// Information about the `extern crate` item or path that caused this crate to be loaded.
140 /// If this is `None`, then the crate was injected (e.g., by the allocator).
141 extern_crate: Lock<Option<ExternCrate>>,
144 /// Holds information about a rustc_span::SourceFile imported from another crate.
145 /// See `imported_source_file()` 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 lazy_state: LazyState,
165 // Used for decoding interpret::AllocIds in a cached & thread-safe manner.
166 alloc_decoding_session: Option<AllocDecodingSession<'a>>,
169 /// Abstract over the various ways one can create metadata decoders.
170 pub(super) trait Metadata<'a, 'tcx>: Copy {
171 fn blob(self) -> &'a MetadataBlob;
173 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
176 fn sess(self) -> Option<&'tcx Session> {
179 fn tcx(self) -> Option<TyCtxt<'tcx>> {
183 fn decoder(self, pos: usize) -> DecodeContext<'a, 'tcx> {
184 let tcx = self.tcx();
186 opaque: MemDecoder::new(self.blob(), pos),
189 sess: self.sess().or(tcx.map(|tcx| tcx.sess)),
191 lazy_state: LazyState::NoNode,
192 alloc_decoding_session: self
194 .map(|cdata| cdata.cdata.alloc_decoding_state.new_decoding_session()),
199 impl<'a, 'tcx> Metadata<'a, 'tcx> for &'a MetadataBlob {
201 fn blob(self) -> &'a MetadataBlob {
206 impl<'a, 'tcx> Metadata<'a, 'tcx> for (&'a MetadataBlob, &'tcx Session) {
208 fn blob(self) -> &'a MetadataBlob {
213 fn sess(self) -> Option<&'tcx Session> {
214 let (_, sess) = self;
219 impl<'a, 'tcx> Metadata<'a, 'tcx> for CrateMetadataRef<'a> {
221 fn blob(self) -> &'a MetadataBlob {
225 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
230 impl<'a, 'tcx> Metadata<'a, 'tcx> for (CrateMetadataRef<'a>, &'tcx Session) {
232 fn blob(self) -> &'a MetadataBlob {
236 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
240 fn sess(self) -> Option<&'tcx Session> {
245 impl<'a, 'tcx> Metadata<'a, 'tcx> for (CrateMetadataRef<'a>, TyCtxt<'tcx>) {
247 fn blob(self) -> &'a MetadataBlob {
251 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
255 fn tcx(self) -> Option<TyCtxt<'tcx>> {
260 impl<T: ParameterizedOverTcx> LazyValue<T> {
261 fn decode<'a, 'tcx, M: Metadata<'a, 'tcx>>(self, metadata: M) -> T::Value<'tcx>
263 T::Value<'tcx>: Decodable<DecodeContext<'a, 'tcx>>,
265 let mut dcx = metadata.decoder(self.position.get());
266 dcx.lazy_state = LazyState::NodeStart(self.position);
267 T::Value::decode(&mut dcx)
271 struct DecodeIterator<'a, 'tcx, T> {
272 elem_counter: std::ops::Range<usize>,
273 dcx: DecodeContext<'a, 'tcx>,
274 _phantom: PhantomData<fn() -> T>,
277 impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> Iterator for DecodeIterator<'a, 'tcx, T> {
281 fn next(&mut self) -> Option<Self::Item> {
282 self.elem_counter.next().map(|_| T::decode(&mut self.dcx))
286 fn size_hint(&self) -> (usize, Option<usize>) {
287 self.elem_counter.size_hint()
291 impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> ExactSizeIterator
292 for DecodeIterator<'a, 'tcx, T>
294 fn len(&self) -> usize {
295 self.elem_counter.len()
299 unsafe impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> TrustedLen
300 for DecodeIterator<'a, 'tcx, T>
304 impl<T: ParameterizedOverTcx> LazyArray<T> {
305 fn decode<'a, 'tcx, M: Metadata<'a, 'tcx>>(
308 ) -> DecodeIterator<'a, 'tcx, T::Value<'tcx>>
310 T::Value<'tcx>: Decodable<DecodeContext<'a, 'tcx>>,
312 let mut dcx = metadata.decoder(self.position.get());
313 dcx.lazy_state = LazyState::NodeStart(self.position);
314 DecodeIterator { elem_counter: (0..self.num_elems), dcx, _phantom: PhantomData }
318 impl<'a, 'tcx> DecodeContext<'a, 'tcx> {
320 fn tcx(&self) -> TyCtxt<'tcx> {
321 debug_assert!(self.tcx.is_some(), "missing TyCtxt in DecodeContext");
326 pub fn blob(&self) -> &'a MetadataBlob {
331 pub fn cdata(&self) -> CrateMetadataRef<'a> {
332 debug_assert!(self.cdata.is_some(), "missing CrateMetadata in DecodeContext");
337 fn map_encoded_cnum_to_current(&self, cnum: CrateNum) -> CrateNum {
338 self.cdata().map_encoded_cnum_to_current(cnum)
342 fn read_lazy_offset_then<T>(&mut self, f: impl Fn(NonZeroUsize) -> T) -> T {
343 let distance = self.read_usize();
344 let position = match self.lazy_state {
345 LazyState::NoNode => bug!("read_lazy_with_meta: outside of a metadata node"),
346 LazyState::NodeStart(start) => {
347 let start = start.get();
348 assert!(distance <= start);
351 LazyState::Previous(last_pos) => last_pos.get() + distance,
353 let position = NonZeroUsize::new(position).unwrap();
354 self.lazy_state = LazyState::Previous(position);
358 fn read_lazy<T>(&mut self) -> LazyValue<T> {
359 self.read_lazy_offset_then(|pos| LazyValue::from_position(pos))
362 fn read_lazy_array<T>(&mut self, len: usize) -> LazyArray<T> {
363 self.read_lazy_offset_then(|pos| LazyArray::from_position_and_num_elems(pos, len))
366 fn read_lazy_table<I, T>(&mut self, len: usize) -> LazyTable<I, T> {
367 self.read_lazy_offset_then(|pos| LazyTable::from_position_and_encoded_size(pos, len))
371 pub fn read_raw_bytes(&mut self, len: usize) -> &[u8] {
372 self.opaque.read_raw_bytes(len)
376 impl<'a, 'tcx> TyDecoder for DecodeContext<'a, 'tcx> {
377 const CLEAR_CROSS_CRATE: bool = true;
379 type I = TyCtxt<'tcx>;
382 fn interner(&self) -> Self::I {
387 fn peek_byte(&self) -> u8 {
388 self.opaque.data[self.opaque.position()]
392 fn position(&self) -> usize {
393 self.opaque.position()
396 fn cached_ty_for_shorthand<F>(&mut self, shorthand: usize, or_insert_with: F) -> Ty<'tcx>
398 F: FnOnce(&mut Self) -> Ty<'tcx>,
400 let tcx = self.tcx();
402 let key = ty::CReaderCacheKey { cnum: Some(self.cdata().cnum), pos: shorthand };
404 if let Some(&ty) = tcx.ty_rcache.borrow().get(&key) {
408 let ty = or_insert_with(self);
409 tcx.ty_rcache.borrow_mut().insert(key, ty);
413 fn with_position<F, R>(&mut self, pos: usize, f: F) -> R
415 F: FnOnce(&mut Self) -> R,
417 let new_opaque = MemDecoder::new(self.opaque.data, pos);
418 let old_opaque = mem::replace(&mut self.opaque, new_opaque);
419 let old_state = mem::replace(&mut self.lazy_state, LazyState::NoNode);
421 self.opaque = old_opaque;
422 self.lazy_state = old_state;
426 fn decode_alloc_id(&mut self) -> rustc_middle::mir::interpret::AllocId {
427 if let Some(alloc_decoding_session) = self.alloc_decoding_session {
428 alloc_decoding_session.decode_alloc_id(self)
430 bug!("Attempting to decode interpret::AllocId without CrateMetadata")
435 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for CrateNum {
436 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> CrateNum {
437 let cnum = CrateNum::from_u32(d.read_u32());
438 d.map_encoded_cnum_to_current(cnum)
442 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for DefIndex {
443 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> DefIndex {
444 DefIndex::from_u32(d.read_u32())
448 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for ExpnIndex {
449 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> ExpnIndex {
450 ExpnIndex::from_u32(d.read_u32())
454 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for SyntaxContext {
455 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> SyntaxContext {
456 let cdata = decoder.cdata();
457 let sess = decoder.sess.unwrap();
458 let cname = cdata.root.name;
459 rustc_span::hygiene::decode_syntax_context(decoder, &cdata.hygiene_context, |_, id| {
460 debug!("SpecializedDecoder<SyntaxContext>: decoding {}", id);
465 .unwrap_or_else(|| panic!("Missing SyntaxContext {:?} for crate {:?}", id, cname))
466 .decode((cdata, sess))
471 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for ExpnId {
472 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> ExpnId {
473 let local_cdata = decoder.cdata();
474 let sess = decoder.sess.unwrap();
476 let cnum = CrateNum::decode(decoder);
477 let index = u32::decode(decoder);
479 let expn_id = rustc_span::hygiene::decode_expn_id(cnum, index, |expn_id| {
480 let ExpnId { krate: cnum, local_id: index } = expn_id;
481 // Lookup local `ExpnData`s in our own crate data. Foreign `ExpnData`s
482 // are stored in the owning crate, to avoid duplication.
483 debug_assert_ne!(cnum, LOCAL_CRATE);
484 let crate_data = if cnum == local_cdata.cnum {
487 local_cdata.cstore.get_crate_data(cnum)
489 let expn_data = crate_data
492 .get(crate_data, index)
494 .decode((crate_data, sess));
495 let expn_hash = crate_data
498 .get(crate_data, index)
500 .decode((crate_data, sess));
501 (expn_data, expn_hash)
507 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for Span {
508 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Span {
509 let ctxt = SyntaxContext::decode(decoder);
510 let tag = u8::decode(decoder);
512 if tag == TAG_PARTIAL_SPAN {
513 return DUMMY_SP.with_ctxt(ctxt);
516 debug_assert!(tag == TAG_VALID_SPAN_LOCAL || tag == TAG_VALID_SPAN_FOREIGN);
518 let lo = BytePos::decode(decoder);
519 let len = BytePos::decode(decoder);
522 let Some(sess) = decoder.sess else {
523 bug!("Cannot decode Span without Session.")
526 // Index of the file in the corresponding crate's list of encoded files.
527 let metadata_index = u32::decode(decoder);
529 // There are two possibilities here:
530 // 1. This is a 'local span', which is located inside a `SourceFile`
531 // that came from this crate. In this case, we use the source map data
532 // encoded in this crate. This branch should be taken nearly all of the time.
533 // 2. This is a 'foreign span', which is located inside a `SourceFile`
534 // that came from a *different* crate (some crate upstream of the one
535 // whose metadata we're looking at). For example, consider this dependency graph:
539 // Suppose that we're currently compiling crate A, and start deserializing
540 // metadata from crate B. When we deserialize a Span from crate B's metadata,
541 // there are two possibilities:
543 // 1. The span references a file from crate B. This makes it a 'local' span,
544 // which means that we can use crate B's serialized source map information.
545 // 2. The span references a file from crate C. This makes it a 'foreign' span,
546 // which means we need to use Crate *C* (not crate B) to determine the source
547 // map information. We only record source map information for a file in the
548 // crate that 'owns' it, so deserializing a Span may require us to look at
549 // a transitive dependency.
551 // When we encode a foreign span, we adjust its 'lo' and 'high' values
552 // to be based on the *foreign* crate (e.g. crate C), not the crate
553 // we are writing metadata for (e.g. crate B). This allows us to
554 // treat the 'local' and 'foreign' cases almost identically during deserialization:
555 // we can call `imported_source_file` for the proper crate, and binary search
556 // through the returned slice using our span.
557 let source_file = if tag == TAG_VALID_SPAN_LOCAL {
558 decoder.cdata().imported_source_file(metadata_index, sess)
560 // When we encode a proc-macro crate, all `Span`s should be encoded
561 // with `TAG_VALID_SPAN_LOCAL`
562 if decoder.cdata().root.is_proc_macro_crate() {
563 // Decode `CrateNum` as u32 - using `CrateNum::decode` will ICE
564 // since we don't have `cnum_map` populated.
565 let cnum = u32::decode(decoder);
567 "Decoding of crate {:?} tried to access proc-macro dep {:?}",
568 decoder.cdata().root.name,
572 // tag is TAG_VALID_SPAN_FOREIGN, checked by `debug_assert` above
573 let cnum = CrateNum::decode(decoder);
575 "SpecializedDecoder<Span>::specialized_decode: loading source files from cnum {:?}",
579 let foreign_data = decoder.cdata().cstore.get_crate_data(cnum);
580 foreign_data.imported_source_file(metadata_index, sess)
583 // Make sure our span is well-formed.
585 lo + source_file.original_start_pos <= source_file.original_end_pos,
586 "Malformed encoded span: lo={:?} source_file.original_start_pos={:?} source_file.original_end_pos={:?}",
588 source_file.original_start_pos,
589 source_file.original_end_pos
592 // Make sure we correctly filtered out invalid spans during encoding.
594 hi + source_file.original_start_pos <= source_file.original_end_pos,
595 "Malformed encoded span: hi={:?} source_file.original_start_pos={:?} source_file.original_end_pos={:?}",
597 source_file.original_start_pos,
598 source_file.original_end_pos
601 let lo = lo + source_file.translated_source_file.start_pos;
602 let hi = hi + source_file.translated_source_file.start_pos;
604 // Do not try to decode parent for foreign spans.
605 Span::new(lo, hi, ctxt, None)
609 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for Symbol {
610 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Self {
611 let tag = d.read_u8();
615 let s = d.read_str();
620 let pos = d.read_usize();
621 let old_pos = d.opaque.position();
623 // move to str ofset and read
624 d.opaque.set_position(pos);
625 let s = d.read_str();
626 let sym = Symbol::intern(s);
629 d.opaque.set_position(old_pos);
633 SYMBOL_PREINTERNED => {
634 let symbol_index = d.read_u32();
635 Symbol::new_from_decoded(symbol_index)
642 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for &'tcx [ty::abstract_const::Node<'tcx>] {
643 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Self {
644 ty::codec::RefDecodable::decode(d)
648 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for &'tcx [(ty::Predicate<'tcx>, Span)] {
649 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Self {
650 ty::codec::RefDecodable::decode(d)
654 impl<'a, 'tcx, T> Decodable<DecodeContext<'a, 'tcx>> for LazyValue<T> {
655 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self {
660 impl<'a, 'tcx, T> Decodable<DecodeContext<'a, 'tcx>> for LazyArray<T> {
661 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self {
662 let len = decoder.read_usize();
663 if len == 0 { LazyArray::empty() } else { decoder.read_lazy_array(len) }
667 impl<'a, 'tcx, I: Idx, T> Decodable<DecodeContext<'a, 'tcx>> for LazyTable<I, T> {
668 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self {
669 let len = decoder.read_usize();
670 decoder.read_lazy_table(len)
674 implement_ty_decoder!(DecodeContext<'a, 'tcx>);
677 pub(crate) fn new(metadata_ref: MetadataRef) -> MetadataBlob {
678 MetadataBlob(Lrc::new(metadata_ref))
681 pub(crate) fn is_compatible(&self) -> bool {
682 self.blob().starts_with(METADATA_HEADER)
685 pub(crate) fn get_rustc_version(&self) -> String {
686 LazyValue::<String>::from_position(NonZeroUsize::new(METADATA_HEADER.len() + 4).unwrap())
690 pub(crate) fn get_root(&self) -> CrateRoot {
691 let slice = &self.blob()[..];
692 let offset = METADATA_HEADER.len();
693 let pos = (((slice[offset + 0] as u32) << 24)
694 | ((slice[offset + 1] as u32) << 16)
695 | ((slice[offset + 2] as u32) << 8)
696 | ((slice[offset + 3] as u32) << 0)) as usize;
697 LazyValue::<CrateRoot>::from_position(NonZeroUsize::new(pos).unwrap()).decode(self)
700 pub(crate) fn list_crate_metadata(&self, out: &mut dyn io::Write) -> io::Result<()> {
701 let root = self.get_root();
702 writeln!(out, "Crate info:")?;
703 writeln!(out, "name {}{}", root.name, root.extra_filename)?;
704 writeln!(out, "hash {} stable_crate_id {:?}", root.hash, root.stable_crate_id)?;
705 writeln!(out, "proc_macro {:?}", root.proc_macro_data.is_some())?;
706 writeln!(out, "=External Dependencies=")?;
707 for (i, dep) in root.crate_deps.decode(self).enumerate() {
710 "{} {}{} hash {} host_hash {:?} kind {:?}",
725 pub(crate) fn is_proc_macro_crate(&self) -> bool {
726 self.proc_macro_data.is_some()
729 pub(crate) fn name(&self) -> Symbol {
733 pub(crate) fn hash(&self) -> Svh {
737 pub(crate) fn stable_crate_id(&self) -> StableCrateId {
741 pub(crate) fn triple(&self) -> &TargetTriple {
745 pub(crate) fn decode_crate_deps<'a>(
747 metadata: &'a MetadataBlob,
748 ) -> impl ExactSizeIterator<Item = CrateDep> + Captures<'a> {
749 self.crate_deps.decode(metadata)
753 impl<'a, 'tcx> CrateMetadataRef<'a> {
754 fn raw_proc_macro(self, id: DefIndex) -> &'a ProcMacro {
755 // DefIndex's in root.proc_macro_data have a one-to-one correspondence
756 // with items in 'raw_proc_macros'.
764 .position(|i| i == id)
766 &self.raw_proc_macros.unwrap()[pos]
769 fn opt_item_name(self, item_index: DefIndex) -> Option<Symbol> {
770 self.def_key(item_index).disambiguated_data.data.get_opt_name()
773 fn item_name(self, item_index: DefIndex) -> Symbol {
774 self.opt_item_name(item_index).expect("no encoded ident for item")
777 fn opt_item_ident(self, item_index: DefIndex, sess: &Session) -> Option<Ident> {
778 let name = self.opt_item_name(item_index)?;
780 self.root.tables.def_ident_span.get(self, item_index).unwrap().decode((self, sess));
781 Some(Ident::new(name, span))
784 fn item_ident(self, item_index: DefIndex, sess: &Session) -> Ident {
785 self.opt_item_ident(item_index, sess).expect("no encoded ident for item")
788 fn maybe_kind(self, item_id: DefIndex) -> Option<EntryKind> {
789 self.root.tables.kind.get(self, item_id).map(|k| k.decode(self))
793 pub(super) fn map_encoded_cnum_to_current(self, cnum: CrateNum) -> CrateNum {
794 if cnum == LOCAL_CRATE { self.cnum } else { self.cnum_map[cnum] }
797 fn kind(self, item_id: DefIndex) -> EntryKind {
798 self.maybe_kind(item_id).unwrap_or_else(|| {
800 "CrateMetadata::kind({:?}): id not found, in crate {:?} with number {}",
808 fn def_kind(self, item_id: DefIndex) -> DefKind {
809 self.root.tables.opt_def_kind.get(self, item_id).unwrap_or_else(|| {
811 "CrateMetadata::def_kind({:?}): id not found, in crate {:?} with number {}",
819 fn get_span(self, index: DefIndex, sess: &Session) -> Span {
824 .unwrap_or_else(|| panic!("Missing span for {:?}", index))
825 .decode((self, sess))
828 fn load_proc_macro(self, id: DefIndex, sess: &Session) -> SyntaxExtension {
829 let (name, kind, helper_attrs) = match *self.raw_proc_macro(id) {
830 ProcMacro::CustomDerive { trait_name, attributes, client } => {
832 attributes.iter().cloned().map(Symbol::intern).collect::<Vec<_>>();
835 SyntaxExtensionKind::Derive(Box::new(DeriveProcMacro { client })),
839 ProcMacro::Attr { name, client } => {
840 (name, SyntaxExtensionKind::Attr(Box::new(AttrProcMacro { client })), Vec::new())
842 ProcMacro::Bang { name, client } => {
843 (name, SyntaxExtensionKind::Bang(Box::new(BangProcMacro { client })), Vec::new())
847 let attrs: Vec<_> = self.get_item_attrs(id, sess).collect();
848 SyntaxExtension::new(
851 self.get_span(id, sess),
854 Symbol::intern(name),
859 fn get_variant(self, kind: &EntryKind, index: DefIndex, parent_did: DefId) -> ty::VariantDef {
860 let data = match kind {
861 EntryKind::Variant(data) | EntryKind::Struct(data) | EntryKind::Union(data) => {
867 let adt_kind = match kind {
868 EntryKind::Variant(_) => ty::AdtKind::Enum,
869 EntryKind::Struct(..) => ty::AdtKind::Struct,
870 EntryKind::Union(..) => ty::AdtKind::Union,
875 if adt_kind == ty::AdtKind::Enum { Some(self.local_def_id(index)) } else { None };
876 let ctor_did = data.ctor.map(|index| self.local_def_id(index));
879 self.item_name(index),
887 .unwrap_or_else(LazyArray::empty)
889 .map(|index| ty::FieldDef {
890 did: self.local_def_id(index),
891 name: self.item_name(index),
892 vis: self.get_visibility(index),
899 data.is_non_exhaustive,
903 fn get_adt_def(self, item_id: DefIndex, tcx: TyCtxt<'tcx>) -> ty::AdtDef<'tcx> {
904 let kind = self.kind(item_id);
905 let did = self.local_def_id(item_id);
907 let adt_kind = match kind {
908 EntryKind::Enum => ty::AdtKind::Enum,
909 EntryKind::Struct(_) => ty::AdtKind::Struct,
910 EntryKind::Union(_) => ty::AdtKind::Union,
911 _ => bug!("get_adt_def called on a non-ADT {:?}", did),
913 let repr = self.root.tables.repr_options.get(self, item_id).unwrap().decode(self);
915 let variants = if let ty::AdtKind::Enum = adt_kind {
920 .unwrap_or_else(LazyArray::empty)
922 .map(|index| self.get_variant(&self.kind(index), index, did))
925 std::iter::once(self.get_variant(&kind, item_id, did)).collect()
928 tcx.alloc_adt_def(did, adt_kind, variants, repr)
931 fn get_generics(self, item_id: DefIndex, sess: &Session) -> ty::Generics {
932 self.root.tables.generics_of.get(self, item_id).unwrap().decode((self, sess))
935 fn get_visibility(self, id: DefIndex) -> ty::Visibility {
936 self.root.tables.visibility.get(self, id).unwrap().decode(self)
939 fn get_trait_item_def_id(self, id: DefIndex) -> Option<DefId> {
940 self.root.tables.trait_item_def_id.get(self, id).map(|d| d.decode_from_cdata(self))
943 fn get_expn_that_defined(self, id: DefIndex, sess: &Session) -> ExpnId {
944 self.root.tables.expn_that_defined.get(self, id).unwrap().decode((self, sess))
947 fn get_debugger_visualizers(self) -> Vec<rustc_span::DebuggerVisualizerFile> {
948 self.root.debugger_visualizers.decode(self).collect::<Vec<_>>()
951 /// Iterates over all the stability attributes in the given crate.
952 fn get_lib_features(self, tcx: TyCtxt<'tcx>) -> &'tcx [(Symbol, Option<Symbol>)] {
953 tcx.arena.alloc_from_iter(self.root.lib_features.decode(self))
956 /// Iterates over the stability implications in the given crate (when a `#[unstable]` attribute
957 /// has an `implied_by` meta item, then the mapping from the implied feature to the actual
958 /// feature is a stability implication).
959 fn get_stability_implications(self, tcx: TyCtxt<'tcx>) -> &'tcx [(Symbol, Symbol)] {
960 tcx.arena.alloc_from_iter(self.root.stability_implications.decode(self))
963 /// Iterates over the language items in the given crate.
964 fn get_lang_items(self, tcx: TyCtxt<'tcx>) -> &'tcx [(DefId, usize)] {
965 tcx.arena.alloc_from_iter(
969 .map(move |(def_index, index)| (self.local_def_id(def_index), index)),
973 /// Iterates over the diagnostic items in the given crate.
974 fn get_diagnostic_items(self) -> DiagnosticItems {
975 let mut id_to_name = FxHashMap::default();
976 let name_to_id = self
980 .map(|(name, def_index)| {
981 let id = self.local_def_id(def_index);
982 id_to_name.insert(id, name);
986 DiagnosticItems { id_to_name, name_to_id }
989 /// Iterates over all named children of the given module,
990 /// including both proper items and reexports.
991 /// Module here is understood in name resolution sense - it can be a `mod` item,
992 /// or a crate root, or an enum, or a trait.
993 fn for_each_module_child(
996 mut callback: impl FnMut(ModChild),
999 if let Some(data) = &self.root.proc_macro_data {
1000 // If we are loading as a proc macro, we want to return
1001 // the view of this crate as a proc macro crate.
1002 if id == CRATE_DEF_INDEX {
1003 for def_index in data.macros.decode(self) {
1004 let raw_macro = self.raw_proc_macro(def_index);
1006 DefKind::Macro(macro_kind(raw_macro)),
1007 self.local_def_id(def_index),
1009 let ident = self.item_ident(def_index, sess);
1013 vis: ty::Visibility::Public,
1022 // Iterate over all children.
1023 if let Some(children) = self.root.tables.children.get(self, id) {
1024 for child_index in children.decode((self, sess)) {
1025 let ident = self.item_ident(child_index, sess);
1026 let kind = self.def_kind(child_index);
1027 let def_id = self.local_def_id(child_index);
1028 let res = Res::Def(kind, def_id);
1029 let vis = self.get_visibility(child_index);
1030 let span = self.get_span(child_index, sess);
1031 let macro_rules = match kind {
1032 DefKind::Macro(..) => match self.kind(child_index) {
1033 EntryKind::MacroDef(_, macro_rules) => macro_rules,
1034 _ => unreachable!(),
1039 callback(ModChild { ident, res, vis, span, macro_rules });
1041 // For non-re-export structs and variants add their constructors to children.
1042 // Re-export lists automatically contain constructors when necessary.
1044 DefKind::Struct => {
1045 if let Some((ctor_def_id, ctor_kind)) =
1046 self.get_ctor_def_id_and_kind(child_index)
1049 Res::Def(DefKind::Ctor(CtorOf::Struct, ctor_kind), ctor_def_id);
1050 let vis = self.get_visibility(ctor_def_id.index);
1060 DefKind::Variant => {
1061 // Braced variants, unlike structs, generate unusable names in
1062 // value namespace, they are reserved for possible future use.
1063 // It's ok to use the variant's id as a ctor id since an
1064 // error will be reported on any use of such resolution anyway.
1065 let (ctor_def_id, ctor_kind) = self
1066 .get_ctor_def_id_and_kind(child_index)
1067 .unwrap_or((def_id, CtorKind::Fictive));
1069 Res::Def(DefKind::Ctor(CtorOf::Variant, ctor_kind), ctor_def_id);
1070 let mut vis = self.get_visibility(ctor_def_id.index);
1071 if ctor_def_id == def_id && vis.is_public() {
1072 // For non-exhaustive variants lower the constructor visibility to
1073 // within the crate. We only need this for fictive constructors,
1074 // for other constructors correct visibilities
1075 // were already encoded in metadata.
1076 let mut attrs = self.get_item_attrs(def_id.index, sess);
1077 if attrs.any(|item| item.has_name(sym::non_exhaustive)) {
1078 let crate_def_id = self.local_def_id(CRATE_DEF_INDEX);
1079 vis = ty::Visibility::Restricted(crate_def_id);
1082 callback(ModChild { ident, res: ctor_res, vis, span, macro_rules: false });
1089 match self.kind(id) {
1090 EntryKind::Mod(exports) => {
1091 for exp in exports.decode((self, sess)) {
1095 EntryKind::Enum | EntryKind::Trait => {}
1096 _ => bug!("`for_each_module_child` is called on a non-module: {:?}", self.def_kind(id)),
1100 fn is_ctfe_mir_available(self, id: DefIndex) -> bool {
1101 self.root.tables.mir_for_ctfe.get(self, id).is_some()
1104 fn is_item_mir_available(self, id: DefIndex) -> bool {
1105 self.root.tables.optimized_mir.get(self, id).is_some()
1108 fn module_expansion(self, id: DefIndex, sess: &Session) -> ExpnId {
1109 match self.kind(id) {
1110 EntryKind::Mod(_) | EntryKind::Enum | EntryKind::Trait => {
1111 self.get_expn_that_defined(id, sess)
1113 _ => panic!("Expected module, found {:?}", self.local_def_id(id)),
1117 fn get_fn_has_self_parameter(self, id: DefIndex) -> bool {
1118 match self.kind(id) {
1119 EntryKind::AssocFn { has_self, .. } => has_self,
1124 fn get_associated_item_def_ids(
1128 ) -> impl Iterator<Item = DefId> + 'a {
1133 .unwrap_or_else(LazyArray::empty)
1134 .decode((self, sess))
1135 .map(move |child_index| self.local_def_id(child_index))
1138 fn get_associated_item(self, id: DefIndex) -> ty::AssocItem {
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 { container, has_self } => (ty::AssocKind::Fn, container, has_self),
1144 EntryKind::AssocType(container) => (ty::AssocKind::Type, container, false),
1145 _ => bug!("cannot get associated-item of `{:?}`", id),
1151 def_id: self.local_def_id(id),
1152 trait_item_def_id: self.get_trait_item_def_id(id),
1154 fn_has_self_parameter: has_self,
1158 fn get_ctor_def_id_and_kind(self, node_id: DefIndex) -> Option<(DefId, CtorKind)> {
1159 match self.kind(node_id) {
1160 EntryKind::Struct(data) | EntryKind::Variant(data) => {
1161 let vdata = data.decode(self);
1162 vdata.ctor.map(|index| (self.local_def_id(index), vdata.ctor_kind))
1172 ) -> impl Iterator<Item = ast::Attribute> + 'a {
1177 .unwrap_or_else(|| {
1178 // Structure and variant constructors don't have any attributes encoded for them,
1179 // but we assume that someone passing a constructor ID actually wants to look at
1180 // the attributes on the corresponding struct or variant.
1181 let def_key = self.def_key(id);
1182 assert_eq!(def_key.disambiguated_data.data, DefPathData::Ctor);
1183 let parent_id = def_key.parent.expect("no parent for a constructor");
1187 .get(self, parent_id)
1188 .expect("no encoded attributes for a structure or variant")
1190 .decode((self, sess))
1193 fn get_struct_field_names(
1197 ) -> impl Iterator<Item = Spanned<Symbol>> + 'a {
1202 .unwrap_or_else(LazyArray::empty)
1204 .map(move |index| respan(self.get_span(index, sess), self.item_name(index)))
1207 fn get_struct_field_visibilities(self, id: DefIndex) -> impl Iterator<Item = Visibility> + 'a {
1212 .unwrap_or_else(LazyArray::empty)
1214 .map(move |field_index| self.get_visibility(field_index))
1217 fn get_inherent_implementations_for_type(
1221 ) -> &'tcx [DefId] {
1222 tcx.arena.alloc_from_iter(
1227 .unwrap_or_else(LazyArray::empty)
1229 .map(|index| self.local_def_id(index)),
1233 /// Decodes all inherent impls in the crate (for rustdoc).
1234 fn get_inherent_impls(self) -> impl Iterator<Item = (DefId, DefId)> + 'a {
1235 (0..self.root.tables.inherent_impls.size()).flat_map(move |i| {
1236 let ty_index = DefIndex::from_usize(i);
1237 let ty_def_id = self.local_def_id(ty_index);
1241 .get(self, ty_index)
1242 .unwrap_or_else(LazyArray::empty)
1244 .map(move |impl_index| (ty_def_id, self.local_def_id(impl_index)))
1248 /// Decodes all traits in the crate (for rustdoc and rustc diagnostics).
1249 fn get_traits(self) -> impl Iterator<Item = DefId> + 'a {
1250 self.root.traits.decode(self).map(move |index| self.local_def_id(index))
1253 /// Decodes all trait impls in the crate (for rustdoc).
1254 fn get_trait_impls(self) -> impl Iterator<Item = (DefId, DefId, Option<SimplifiedType>)> + 'a {
1255 self.cdata.trait_impls.iter().flat_map(move |(&(trait_cnum_raw, trait_index), impls)| {
1256 let trait_def_id = DefId {
1257 krate: self.cnum_map[CrateNum::from_u32(trait_cnum_raw)],
1260 impls.decode(self).map(move |(impl_index, simplified_self_ty)| {
1261 (trait_def_id, self.local_def_id(impl_index), simplified_self_ty)
1266 fn get_all_incoherent_impls(self) -> impl Iterator<Item = DefId> + 'a {
1270 .flat_map(move |impls| impls.decode(self).map(move |idx| self.local_def_id(idx)))
1273 fn get_incoherent_impls(self, tcx: TyCtxt<'tcx>, simp: SimplifiedType) -> &'tcx [DefId] {
1274 if let Some(impls) = self.cdata.incoherent_impls.get(&simp) {
1275 tcx.arena.alloc_from_iter(impls.decode(self).map(|idx| self.local_def_id(idx)))
1281 fn get_implementations_of_trait(
1284 trait_def_id: DefId,
1285 ) -> &'tcx [(DefId, Option<SimplifiedType>)] {
1286 if self.trait_impls.is_empty() {
1290 // Do a reverse lookup beforehand to avoid touching the crate_num
1291 // hash map in the loop below.
1292 let key = match self.reverse_translate_def_id(trait_def_id) {
1293 Some(def_id) => (def_id.krate.as_u32(), def_id.index),
1297 if let Some(impls) = self.trait_impls.get(&key) {
1298 tcx.arena.alloc_from_iter(
1301 .map(|(idx, simplified_self_ty)| (self.local_def_id(idx), simplified_self_ty)),
1308 fn get_native_libraries(self, sess: &'a Session) -> impl Iterator<Item = NativeLib> + 'a {
1309 self.root.native_libraries.decode((self, sess))
1312 fn get_proc_macro_quoted_span(self, index: usize, sess: &Session) -> Span {
1315 .proc_macro_quoted_spans
1317 .unwrap_or_else(|| panic!("Missing proc macro quoted span: {:?}", index))
1318 .decode((self, sess))
1321 fn get_foreign_modules(self, sess: &'a Session) -> impl Iterator<Item = ForeignModule> + '_ {
1322 self.root.foreign_modules.decode((self, sess))
1325 fn get_dylib_dependency_formats(
1328 ) -> &'tcx [(CrateNum, LinkagePreference)] {
1329 tcx.arena.alloc_from_iter(
1330 self.root.dylib_dependency_formats.decode(self).enumerate().flat_map(|(i, link)| {
1331 let cnum = CrateNum::new(i + 1);
1332 link.map(|link| (self.cnum_map[cnum], link))
1337 fn get_missing_lang_items(self, tcx: TyCtxt<'tcx>) -> &'tcx [lang_items::LangItem] {
1338 tcx.arena.alloc_from_iter(self.root.lang_items_missing.decode(self))
1341 fn exported_symbols(
1344 ) -> &'tcx [(ExportedSymbol<'tcx>, SymbolExportInfo)] {
1345 tcx.arena.alloc_from_iter(self.root.exported_symbols.decode((self, tcx)))
1348 fn get_macro(self, id: DefIndex, sess: &Session) -> ast::MacroDef {
1349 match self.kind(id) {
1350 EntryKind::MacroDef(mac_args, macro_rules) => {
1351 ast::MacroDef { body: P(mac_args.decode((self, sess))), macro_rules }
1357 fn is_foreign_item(self, id: DefIndex) -> bool {
1358 match self.kind(id) {
1359 EntryKind::ForeignStatic | EntryKind::ForeignFn => true,
1365 fn def_key(self, index: DefIndex) -> DefKey {
1370 .or_insert_with(|| self.root.tables.def_keys.get(self, index).unwrap().decode(self))
1373 // Returns the path leading to the thing with this `id`.
1374 fn def_path(self, id: DefIndex) -> DefPath {
1375 debug!("def_path(cnum={:?}, id={:?})", self.cnum, id);
1376 DefPath::make(self.cnum, id, |parent| self.def_key(parent))
1379 fn def_path_hash_unlocked(
1382 def_path_hashes: &mut FxHashMap<DefIndex, DefPathHash>,
1386 .or_insert_with(|| self.root.tables.def_path_hashes.get(self, index).unwrap())
1390 fn def_path_hash(self, index: DefIndex) -> DefPathHash {
1391 let mut def_path_hashes = self.def_path_hash_cache.lock();
1392 self.def_path_hash_unlocked(index, &mut def_path_hashes)
1396 fn def_path_hash_to_def_index(self, hash: DefPathHash) -> DefIndex {
1397 self.def_path_hash_map.def_path_hash_to_def_index(&hash)
1400 fn expn_hash_to_expn_id(self, sess: &Session, index_guess: u32, hash: ExpnHash) -> ExpnId {
1401 debug_assert_eq!(ExpnId::from_hash(hash), None);
1402 let index_guess = ExpnIndex::from_u32(index_guess);
1403 let old_hash = self.root.expn_hashes.get(self, index_guess).map(|lazy| lazy.decode(self));
1405 let index = if old_hash == Some(hash) {
1406 // Fast path: the expn and its index is unchanged from the
1407 // previous compilation session. There is no need to decode anything
1411 // Slow path: We need to find out the new `DefIndex` of the provided
1412 // `DefPathHash`, if its still exists. This requires decoding every `DefPathHash`
1413 // stored in this crate.
1414 let map = self.cdata.expn_hash_map.get_or_init(|| {
1415 let end_id = self.root.expn_hashes.size() as u32;
1417 UnhashMap::with_capacity_and_hasher(end_id as usize, Default::default());
1418 for i in 0..end_id {
1419 let i = ExpnIndex::from_u32(i);
1420 if let Some(hash) = self.root.expn_hashes.get(self, i) {
1421 map.insert(hash.decode(self), i);
1429 let data = self.root.expn_data.get(self, index).unwrap().decode((self, sess));
1430 rustc_span::hygiene::register_expn_id(self.cnum, index, data, hash)
1433 /// Imports the source_map from an external crate into the source_map of the crate
1434 /// currently being compiled (the "local crate").
1436 /// The import algorithm works analogous to how AST items are inlined from an
1437 /// external crate's metadata:
1438 /// For every SourceFile in the external source_map an 'inline' copy is created in the
1439 /// local source_map. The correspondence relation between external and local
1440 /// SourceFiles is recorded in the `ImportedSourceFile` objects returned from this
1441 /// function. When an item from an external crate is later inlined into this
1442 /// crate, this correspondence information is used to translate the span
1443 /// information of the inlined item so that it refers the correct positions in
1444 /// the local source_map (see `<decoder::DecodeContext as SpecializedDecoder<Span>>`).
1446 /// The import algorithm in the function below will reuse SourceFiles already
1447 /// existing in the local source_map. For example, even if the SourceFile of some
1448 /// source file of libstd gets imported many times, there will only ever be
1449 /// one SourceFile object for the corresponding file in the local source_map.
1451 /// Note that imported SourceFiles do not actually contain the source code of the
1452 /// file they represent, just information about length, line breaks, and
1453 /// multibyte characters. This information is enough to generate valid debuginfo
1454 /// for items inlined from other crates.
1456 /// Proc macro crates don't currently export spans, so this function does not have
1457 /// to work for them.
1458 fn imported_source_file(self, source_file_index: u32, sess: &Session) -> ImportedSourceFile {
1459 fn filter<'a>(sess: &Session, path: Option<&'a Path>) -> Option<&'a Path> {
1461 // Only spend time on further checks if we have what to translate *to*.
1462 sess.opts.real_rust_source_base_dir.is_some()
1463 // Some tests need the translation to be always skipped.
1464 && sess.opts.unstable_opts.translate_remapped_path_to_local_path
1466 .filter(|virtual_dir| {
1467 // Don't translate away `/rustc/$hash` if we're still remapping to it,
1468 // since that means we're still building `std`/`rustc` that need it,
1469 // and we don't want the real path to leak into codegen/debuginfo.
1470 !sess.opts.remap_path_prefix.iter().any(|(_from, to)| to == virtual_dir)
1474 // Translate the virtual `/rustc/$hash` prefix back to a real directory
1475 // that should hold actual sources, where possible.
1477 // NOTE: if you update this, you might need to also update bootstrap's code for generating
1478 // the `rust-src` component in `Src::run` in `src/bootstrap/dist.rs`.
1479 let virtual_rust_source_base_dir = [
1480 filter(sess, option_env!("CFG_VIRTUAL_RUST_SOURCE_BASE_DIR").map(Path::new)),
1481 filter(sess, sess.opts.unstable_opts.simulate_remapped_rust_src_base.as_deref()),
1484 let try_to_translate_virtual_to_real = |name: &mut rustc_span::FileName| {
1486 "try_to_translate_virtual_to_real(name={:?}): \
1487 virtual_rust_source_base_dir={:?}, real_rust_source_base_dir={:?}",
1488 name, virtual_rust_source_base_dir, sess.opts.real_rust_source_base_dir,
1491 for virtual_dir in virtual_rust_source_base_dir.iter().flatten() {
1492 if let Some(real_dir) = &sess.opts.real_rust_source_base_dir {
1493 if let rustc_span::FileName::Real(old_name) = name {
1494 if let rustc_span::RealFileName::Remapped { local_path: _, virtual_name } =
1497 if let Ok(rest) = virtual_name.strip_prefix(virtual_dir) {
1498 let virtual_name = virtual_name.clone();
1500 // The std library crates are in
1501 // `$sysroot/lib/rustlib/src/rust/library`, whereas other crates
1502 // may be in `$sysroot/lib/rustlib/src/rust/` directly. So we
1503 // detect crates from the std libs and handle them specially.
1504 const STD_LIBS: &[&str] = &[
1514 "profiler_builtins",
1516 "rustc-std-workspace-core",
1517 "rustc-std-workspace-alloc",
1518 "rustc-std-workspace-std",
1521 let is_std_lib = STD_LIBS.iter().any(|l| rest.starts_with(l));
1523 let new_path = if is_std_lib {
1524 real_dir.join("library").join(rest)
1530 "try_to_translate_virtual_to_real: `{}` -> `{}`",
1531 virtual_name.display(),
1534 let new_name = rustc_span::RealFileName::Remapped {
1535 local_path: Some(new_path),
1538 *old_name = new_name;
1546 let mut import_info = self.cdata.source_map_import_info.lock();
1547 for _ in import_info.len()..=(source_file_index as usize) {
1548 import_info.push(None);
1550 import_info[source_file_index as usize]
1551 .get_or_insert_with(|| {
1552 let source_file_to_import = self
1555 .get(self, source_file_index)
1556 .expect("missing source file")
1559 // We can't reuse an existing SourceFile, so allocate a new one
1560 // containing the information we need.
1561 let rustc_span::SourceFile {
1572 } = source_file_to_import;
1574 // If this file is under $sysroot/lib/rustlib/src/ but has not been remapped
1575 // during rust bootstrapping by `remap-debuginfo = true`, and the user
1576 // wish to simulate that behaviour by -Z simulate-remapped-rust-src-base,
1577 // then we change `name` to a similar state as if the rust was bootstrapped
1578 // with `remap-debuginfo = true`.
1579 // This is useful for testing so that tests about the effects of
1580 // `try_to_translate_virtual_to_real` don't have to worry about how the
1581 // compiler is bootstrapped.
1582 if let Some(virtual_dir) = &sess.opts.unstable_opts.simulate_remapped_rust_src_base
1584 if let Some(real_dir) = &sess.opts.real_rust_source_base_dir {
1585 if let rustc_span::FileName::Real(ref mut old_name) = name {
1586 if let rustc_span::RealFileName::LocalPath(local) = old_name {
1587 if let Ok(rest) = local.strip_prefix(real_dir) {
1588 *old_name = rustc_span::RealFileName::Remapped {
1590 virtual_name: virtual_dir.join(rest),
1598 // If this file's path has been remapped to `/rustc/$hash`,
1599 // we might be able to reverse that (also see comments above,
1600 // on `try_to_translate_virtual_to_real`).
1601 try_to_translate_virtual_to_real(&mut name);
1603 let source_length = (end_pos - start_pos).to_usize();
1605 let local_version = sess.source_map().new_imported_source_file(
1619 "CrateMetaData::imported_source_files alloc \
1620 source_file {:?} original (start_pos {:?} end_pos {:?}) \
1621 translated (start_pos {:?} end_pos {:?})",
1625 local_version.start_pos,
1626 local_version.end_pos
1629 ImportedSourceFile {
1630 original_start_pos: start_pos,
1631 original_end_pos: end_pos,
1632 translated_source_file: local_version,
1638 fn get_generator_diagnostic_data(
1642 ) -> Option<GeneratorDiagnosticData<'tcx>> {
1645 .generator_diagnostic_data
1647 .map(|param| param.decode((self, tcx)))
1648 .map(|generator_data| GeneratorDiagnosticData {
1649 generator_interior_types: generator_data.generator_interior_types,
1650 hir_owner: generator_data.hir_owner,
1651 nodes_types: generator_data.nodes_types,
1652 adjustments: generator_data.adjustments,
1656 fn get_may_have_doc_links(self, index: DefIndex) -> bool {
1657 self.root.tables.may_have_doc_links.get(self, index).is_some()
1660 fn get_is_intrinsic(self, index: DefIndex) -> bool {
1661 self.root.tables.is_intrinsic.get(self, index).is_some()
1665 impl CrateMetadata {
1671 raw_proc_macros: Option<&'static [ProcMacro]>,
1673 cnum_map: CrateNumMap,
1674 dep_kind: CrateDepKind,
1675 source: CrateSource,
1677 host_hash: Option<Svh>,
1678 ) -> CrateMetadata {
1679 let trait_impls = root
1681 .decode((&blob, sess))
1682 .map(|trait_impls| (trait_impls.trait_id, trait_impls.impls))
1684 let alloc_decoding_state =
1685 AllocDecodingState::new(root.interpret_alloc_index.decode(&blob).collect());
1686 let dependencies = Lock::new(cnum_map.iter().cloned().collect());
1688 // Pre-decode the DefPathHash->DefIndex table. This is a cheap operation
1689 // that does not copy any data. It just does some data verification.
1690 let def_path_hash_map = root.def_path_hash_map.decode(&blob);
1692 let mut cdata = CrateMetadata {
1696 incoherent_impls: Default::default(),
1698 source_map_import_info: Lock::new(Vec::new()),
1700 expn_hash_map: Default::default(),
1701 alloc_decoding_state,
1705 dep_kind: Lock::new(dep_kind),
1706 source: Lrc::new(source),
1709 extern_crate: Lock::new(None),
1710 hygiene_context: Default::default(),
1711 def_key_cache: Default::default(),
1712 def_path_hash_cache: Default::default(),
1715 // Need `CrateMetadataRef` to decode `DefId`s in simplified types.
1716 cdata.incoherent_impls = cdata
1719 .decode(CrateMetadataRef { cdata: &cdata, cstore })
1720 .map(|incoherent_impls| (incoherent_impls.self_ty, incoherent_impls.impls))
1726 pub(crate) fn dependencies(&self) -> LockGuard<'_, Vec<CrateNum>> {
1727 self.dependencies.borrow()
1730 pub(crate) fn add_dependency(&self, cnum: CrateNum) {
1731 self.dependencies.borrow_mut().push(cnum);
1734 pub(crate) fn update_extern_crate(&self, new_extern_crate: ExternCrate) -> bool {
1735 let mut extern_crate = self.extern_crate.borrow_mut();
1736 let update = Some(new_extern_crate.rank()) > extern_crate.as_ref().map(ExternCrate::rank);
1738 *extern_crate = Some(new_extern_crate);
1743 pub(crate) fn source(&self) -> &CrateSource {
1747 pub(crate) fn dep_kind(&self) -> CrateDepKind {
1748 *self.dep_kind.lock()
1751 pub(crate) fn update_dep_kind(&self, f: impl FnOnce(CrateDepKind) -> CrateDepKind) {
1752 self.dep_kind.with_lock(|dep_kind| *dep_kind = f(*dep_kind))
1755 pub(crate) fn required_panic_strategy(&self) -> Option<PanicStrategy> {
1756 self.root.required_panic_strategy
1759 pub(crate) fn needs_panic_runtime(&self) -> bool {
1760 self.root.needs_panic_runtime
1763 pub(crate) fn is_panic_runtime(&self) -> bool {
1764 self.root.panic_runtime
1767 pub(crate) fn is_profiler_runtime(&self) -> bool {
1768 self.root.profiler_runtime
1771 pub(crate) fn needs_allocator(&self) -> bool {
1772 self.root.needs_allocator
1775 pub(crate) fn has_global_allocator(&self) -> bool {
1776 self.root.has_global_allocator
1779 pub(crate) fn has_default_lib_allocator(&self) -> bool {
1780 self.root.has_default_lib_allocator
1783 pub(crate) fn is_proc_macro_crate(&self) -> bool {
1784 self.root.is_proc_macro_crate()
1787 pub(crate) fn name(&self) -> Symbol {
1791 pub(crate) fn stable_crate_id(&self) -> StableCrateId {
1792 self.root.stable_crate_id
1795 pub(crate) fn hash(&self) -> Svh {
1799 fn num_def_ids(&self) -> usize {
1800 self.root.tables.def_keys.size()
1803 fn local_def_id(&self, index: DefIndex) -> DefId {
1804 DefId { krate: self.cnum, index }
1807 // Translate a DefId from the current compilation environment to a DefId
1808 // for an external crate.
1809 fn reverse_translate_def_id(&self, did: DefId) -> Option<DefId> {
1810 for (local, &global) in self.cnum_map.iter_enumerated() {
1811 if global == did.krate {
1812 return Some(DefId { krate: local, index: did.index });
1820 // Cannot be implemented on 'ProcMacro', as libproc_macro
1821 // does not depend on librustc_ast
1822 fn macro_kind(raw: &ProcMacro) -> MacroKind {
1824 ProcMacro::CustomDerive { .. } => MacroKind::Derive,
1825 ProcMacro::Attr { .. } => MacroKind::Attr,
1826 ProcMacro::Bang { .. } => MacroKind::Bang,