1 // Decoding metadata from a single crate's metadata
3 use crate::creader::CrateMetadataRef;
4 use crate::rmeta::table::{FixedSizeEncoding, Table};
8 use rustc_attr as attr;
9 use rustc_data_structures::captures::Captures;
10 use rustc_data_structures::fx::FxHashMap;
11 use rustc_data_structures::svh::Svh;
12 use rustc_data_structures::sync::{Lock, LockGuard, Lrc, OnceCell};
13 use rustc_data_structures::unhash::UnhashMap;
14 use rustc_errors::ErrorReported;
15 use rustc_expand::base::{SyntaxExtension, SyntaxExtensionKind};
16 use rustc_expand::proc_macro::{AttrProcMacro, BangProcMacro, ProcMacroDerive};
18 use rustc_hir::def::{CtorKind, CtorOf, DefKind, Res};
19 use rustc_hir::def_id::{CrateNum, DefId, DefIndex, CRATE_DEF_INDEX, LOCAL_CRATE};
20 use rustc_hir::definitions::{DefKey, DefPath, DefPathData, DefPathHash};
21 use rustc_hir::lang_items;
22 use rustc_index::vec::{Idx, IndexVec};
23 use rustc_middle::hir::exports::Export;
24 use rustc_middle::middle::cstore::{CrateSource, ExternCrate};
25 use rustc_middle::middle::cstore::{ForeignModule, LinkagePreference, NativeLib};
26 use rustc_middle::middle::exported_symbols::{ExportedSymbol, SymbolExportLevel};
27 use rustc_middle::mir::interpret::{AllocDecodingSession, AllocDecodingState};
28 use rustc_middle::mir::{self, Body, Promoted};
29 use rustc_middle::thir;
30 use rustc_middle::ty::codec::TyDecoder;
31 use rustc_middle::ty::{self, Ty, TyCtxt, Visibility};
32 use rustc_serialize::{opaque, Decodable, Decoder};
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;
42 use std::num::NonZeroUsize;
46 pub use cstore_impl::{provide, provide_extern};
47 use rustc_span::hygiene::HygieneDecodeContext;
51 crate struct MetadataBlob(MetadataRef);
53 // A map from external crate numbers (as decoded from some crate file) to
54 // local crate numbers (as generated during this session). Each external
55 // crate may refer to types in other external crates, and each has their
57 crate type CrateNumMap = IndexVec<CrateNum, CrateNum>;
59 crate struct CrateMetadata {
60 /// The primary crate data - binary metadata blob.
63 // --- Some data pre-decoded from the metadata blob, usually for performance ---
64 /// Properties of the whole crate.
65 /// NOTE(eddyb) we pass `'static` to a `'tcx` parameter because this
66 /// lifetime is only used behind `Lazy`, and therefore acts like a
67 /// universal (`for<'tcx>`), that is paired up with whichever `TyCtxt`
68 /// is being used to decode those values.
69 root: CrateRoot<'static>,
71 /// FIXME: Used only from queries and can use query cache,
72 /// so pre-decoding can probably be avoided.
74 FxHashMap<(u32, DefIndex), Lazy<[(DefIndex, Option<ty::fast_reject::SimplifiedType>)]>>,
75 /// Proc macro descriptions for this crate, if it's a proc macro crate.
76 raw_proc_macros: Option<&'static [ProcMacro]>,
77 /// Source maps for code from the crate.
78 source_map_import_info: OnceCell<Vec<ImportedSourceFile>>,
79 /// For every definition in this crate, maps its `DefPathHash` to its
80 /// `DefIndex`. See `raw_def_id_to_def_id` for more details about how
82 def_path_hash_map: OnceCell<UnhashMap<DefPathHash, DefIndex>>,
83 /// Likewise for ExpnHash.
84 expn_hash_map: OnceCell<UnhashMap<ExpnHash, ExpnIndex>>,
85 /// Used for decoding interpret::AllocIds in a cached & thread-safe manner.
86 alloc_decoding_state: AllocDecodingState,
87 /// Caches decoded `DefKey`s.
88 def_key_cache: Lock<FxHashMap<DefIndex, DefKey>>,
89 /// Caches decoded `DefPathHash`es.
90 def_path_hash_cache: Lock<FxHashMap<DefIndex, DefPathHash>>,
92 // --- Other significant crate properties ---
93 /// ID of this crate, from the current compilation session's point of view.
95 /// Maps crate IDs as they are were seen from this crate's compilation sessions into
96 /// IDs as they are seen from the current compilation session.
97 cnum_map: CrateNumMap,
98 /// Same ID set as `cnum_map` plus maybe some injected crates like panic runtime.
99 dependencies: Lock<Vec<CrateNum>>,
100 /// How to link (or not link) this crate to the currently compiled crate.
101 dep_kind: Lock<CrateDepKind>,
102 /// Filesystem location of this crate.
104 /// Whether or not this crate should be consider a private dependency
105 /// for purposes of the 'exported_private_dependencies' lint
107 /// The hash for the host proc macro. Used to support `-Z dual-proc-macro`.
108 host_hash: Option<Svh>,
110 /// Additional data used for decoding `HygieneData` (e.g. `SyntaxContext`
112 /// Note that we store a `HygieneDecodeContext` for each `CrateMetadat`. This is
113 /// because `SyntaxContext` ids are not globally unique, so we need
114 /// to track which ids we've decoded on a per-crate basis.
115 hygiene_context: HygieneDecodeContext,
117 // --- Data used only for improving diagnostics ---
118 /// Information about the `extern crate` item or path that caused this crate to be loaded.
119 /// If this is `None`, then the crate was injected (e.g., by the allocator).
120 extern_crate: Lock<Option<ExternCrate>>,
123 /// Holds information about a rustc_span::SourceFile imported from another crate.
124 /// See `imported_source_files()` for more information.
125 struct ImportedSourceFile {
126 /// This SourceFile's byte-offset within the source_map of its original crate
127 original_start_pos: rustc_span::BytePos,
128 /// The end of this SourceFile within the source_map of its original crate
129 original_end_pos: rustc_span::BytePos,
130 /// The imported SourceFile's representation within the local source_map
131 translated_source_file: Lrc<rustc_span::SourceFile>,
134 pub(super) struct DecodeContext<'a, 'tcx> {
135 opaque: opaque::Decoder<'a>,
136 cdata: Option<CrateMetadataRef<'a>>,
137 sess: Option<&'tcx Session>,
138 tcx: Option<TyCtxt<'tcx>>,
140 // Cache the last used source_file for translating spans as an optimization.
141 last_source_file_index: usize,
143 lazy_state: LazyState,
145 // Used for decoding interpret::AllocIds in a cached & thread-safe manner.
146 alloc_decoding_session: Option<AllocDecodingSession<'a>>,
149 /// Abstract over the various ways one can create metadata decoders.
150 pub(super) trait Metadata<'a, 'tcx>: Copy {
151 fn raw_bytes(self) -> &'a [u8];
152 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
155 fn sess(self) -> Option<&'tcx Session> {
158 fn tcx(self) -> Option<TyCtxt<'tcx>> {
162 fn decoder(self, pos: usize) -> DecodeContext<'a, 'tcx> {
163 let tcx = self.tcx();
165 opaque: opaque::Decoder::new(self.raw_bytes(), pos),
167 sess: self.sess().or(tcx.map(|tcx| tcx.sess)),
169 last_source_file_index: 0,
170 lazy_state: LazyState::NoNode,
171 alloc_decoding_session: self
173 .map(|cdata| cdata.cdata.alloc_decoding_state.new_decoding_session()),
178 impl<'a, 'tcx> Metadata<'a, 'tcx> for &'a MetadataBlob {
179 fn raw_bytes(self) -> &'a [u8] {
184 impl<'a, 'tcx> Metadata<'a, 'tcx> for (&'a MetadataBlob, &'tcx Session) {
185 fn raw_bytes(self) -> &'a [u8] {
186 let (blob, _) = self;
190 fn sess(self) -> Option<&'tcx Session> {
191 let (_, sess) = self;
196 impl<'a, 'tcx> Metadata<'a, 'tcx> for &'a CrateMetadataRef<'a> {
197 fn raw_bytes(self) -> &'a [u8] {
198 self.blob.raw_bytes()
200 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
205 impl<'a, 'tcx> Metadata<'a, 'tcx> for (&'a CrateMetadataRef<'a>, &'tcx Session) {
206 fn raw_bytes(self) -> &'a [u8] {
209 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
212 fn sess(self) -> Option<&'tcx Session> {
217 impl<'a, 'tcx> Metadata<'a, 'tcx> for (&'a CrateMetadataRef<'a>, TyCtxt<'tcx>) {
218 fn raw_bytes(self) -> &'a [u8] {
221 fn cdata(self) -> Option<CrateMetadataRef<'a>> {
224 fn tcx(self) -> Option<TyCtxt<'tcx>> {
229 impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> Lazy<T> {
230 fn decode<M: Metadata<'a, 'tcx>>(self, metadata: M) -> T {
231 let mut dcx = metadata.decoder(self.position.get());
232 dcx.lazy_state = LazyState::NodeStart(self.position);
233 T::decode(&mut dcx).unwrap()
237 impl<'a: 'x, 'tcx: 'x, 'x, T: Decodable<DecodeContext<'a, 'tcx>>> Lazy<[T]> {
238 fn decode<M: Metadata<'a, 'tcx>>(
241 ) -> impl ExactSizeIterator<Item = T> + Captures<'a> + Captures<'tcx> + 'x {
242 let mut dcx = metadata.decoder(self.position.get());
243 dcx.lazy_state = LazyState::NodeStart(self.position);
244 (0..self.meta).map(move |_| T::decode(&mut dcx).unwrap())
248 impl<'a, 'tcx> DecodeContext<'a, 'tcx> {
249 fn tcx(&self) -> TyCtxt<'tcx> {
250 self.tcx.expect("missing TyCtxt in DecodeContext")
253 fn cdata(&self) -> CrateMetadataRef<'a> {
254 self.cdata.expect("missing CrateMetadata in DecodeContext")
257 fn map_encoded_cnum_to_current(&self, cnum: CrateNum) -> CrateNum {
258 if cnum == LOCAL_CRATE { self.cdata().cnum } else { self.cdata().cnum_map[cnum] }
261 fn read_lazy_with_meta<T: ?Sized + LazyMeta>(
264 ) -> Result<Lazy<T>, <Self as Decoder>::Error> {
265 let min_size = T::min_size(meta);
266 let distance = self.read_usize()?;
267 let position = match self.lazy_state {
268 LazyState::NoNode => bug!("read_lazy_with_meta: outside of a metadata node"),
269 LazyState::NodeStart(start) => {
270 let start = start.get();
271 assert!(distance + min_size <= start);
272 start - distance - min_size
274 LazyState::Previous(last_min_end) => last_min_end.get() + distance,
276 self.lazy_state = LazyState::Previous(NonZeroUsize::new(position + min_size).unwrap());
277 Ok(Lazy::from_position_and_meta(NonZeroUsize::new(position).unwrap(), meta))
281 impl<'a, 'tcx> TyDecoder<'tcx> for DecodeContext<'a, 'tcx> {
282 const CLEAR_CROSS_CRATE: bool = true;
285 fn tcx(&self) -> TyCtxt<'tcx> {
286 self.tcx.expect("missing TyCtxt in DecodeContext")
290 fn peek_byte(&self) -> u8 {
291 self.opaque.data[self.opaque.position()]
295 fn position(&self) -> usize {
296 self.opaque.position()
299 fn cached_ty_for_shorthand<F>(
303 ) -> Result<Ty<'tcx>, Self::Error>
305 F: FnOnce(&mut Self) -> Result<Ty<'tcx>, Self::Error>,
307 let tcx = self.tcx();
309 let key = ty::CReaderCacheKey { cnum: Some(self.cdata().cnum), pos: shorthand };
311 if let Some(&ty) = tcx.ty_rcache.borrow().get(&key) {
315 let ty = or_insert_with(self)?;
316 tcx.ty_rcache.borrow_mut().insert(key, ty);
320 fn with_position<F, R>(&mut self, pos: usize, f: F) -> R
322 F: FnOnce(&mut Self) -> R,
324 let new_opaque = opaque::Decoder::new(self.opaque.data, pos);
325 let old_opaque = mem::replace(&mut self.opaque, new_opaque);
326 let old_state = mem::replace(&mut self.lazy_state, LazyState::NoNode);
328 self.opaque = old_opaque;
329 self.lazy_state = old_state;
333 fn decode_alloc_id(&mut self) -> Result<rustc_middle::mir::interpret::AllocId, Self::Error> {
334 if let Some(alloc_decoding_session) = self.alloc_decoding_session {
335 alloc_decoding_session.decode_alloc_id(self)
337 bug!("Attempting to decode interpret::AllocId without CrateMetadata")
342 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for CrateNum {
343 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Result<CrateNum, String> {
344 let cnum = CrateNum::from_u32(d.read_u32()?);
345 Ok(d.map_encoded_cnum_to_current(cnum))
349 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for DefIndex {
350 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Result<DefIndex, String> {
351 Ok(DefIndex::from_u32(d.read_u32()?))
355 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for ExpnIndex {
356 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Result<ExpnIndex, String> {
357 Ok(ExpnIndex::from_u32(d.read_u32()?))
361 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for SyntaxContext {
362 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Result<SyntaxContext, String> {
363 let cdata = decoder.cdata();
364 let sess = decoder.sess.unwrap();
365 let cname = cdata.root.name;
366 rustc_span::hygiene::decode_syntax_context(decoder, &cdata.hygiene_context, |_, id| {
367 debug!("SpecializedDecoder<SyntaxContext>: decoding {}", id);
372 .unwrap_or_else(|| panic!("Missing SyntaxContext {:?} for crate {:?}", id, cname))
373 .decode((&cdata, sess)))
378 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for ExpnId {
379 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Result<ExpnId, String> {
380 let local_cdata = decoder.cdata();
381 let sess = decoder.sess.unwrap();
383 let cnum = CrateNum::decode(decoder)?;
384 let index = u32::decode(decoder)?;
386 let expn_id = rustc_span::hygiene::decode_expn_id(cnum, index, |expn_id| {
387 let ExpnId { krate: cnum, local_id: index } = expn_id;
388 // Lookup local `ExpnData`s in our own crate data. Foreign `ExpnData`s
389 // are stored in the owning crate, to avoid duplication.
390 debug_assert_ne!(cnum, LOCAL_CRATE);
391 let crate_data = if cnum == local_cdata.cnum {
394 local_cdata.cstore.get_crate_data(cnum)
396 let expn_data = crate_data
399 .get(&crate_data, index)
401 .decode((&crate_data, sess));
402 let expn_hash = crate_data
405 .get(&crate_data, index)
407 .decode((&crate_data, sess));
408 (expn_data, expn_hash)
414 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for Span {
415 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Result<Span, String> {
416 let ctxt = SyntaxContext::decode(decoder)?;
417 let tag = u8::decode(decoder)?;
419 if tag == TAG_PARTIAL_SPAN {
420 return Ok(DUMMY_SP.with_ctxt(ctxt));
423 debug_assert!(tag == TAG_VALID_SPAN_LOCAL || tag == TAG_VALID_SPAN_FOREIGN);
425 let lo = BytePos::decode(decoder)?;
426 let len = BytePos::decode(decoder)?;
429 let sess = if let Some(sess) = decoder.sess {
432 bug!("Cannot decode Span without Session.")
435 // There are two possibilities here:
436 // 1. This is a 'local span', which is located inside a `SourceFile`
437 // that came from this crate. In this case, we use the source map data
438 // encoded in this crate. This branch should be taken nearly all of the time.
439 // 2. This is a 'foreign span', which is located inside a `SourceFile`
440 // that came from a *different* crate (some crate upstream of the one
441 // whose metadata we're looking at). For example, consider this dependency graph:
445 // Suppose that we're currently compiling crate A, and start deserializing
446 // metadata from crate B. When we deserialize a Span from crate B's metadata,
447 // there are two posibilites:
449 // 1. The span references a file from crate B. This makes it a 'local' span,
450 // which means that we can use crate B's serialized source map information.
451 // 2. The span references a file from crate C. This makes it a 'foreign' span,
452 // which means we need to use Crate *C* (not crate B) to determine the source
453 // map information. We only record source map information for a file in the
454 // crate that 'owns' it, so deserializing a Span may require us to look at
455 // a transitive dependency.
457 // When we encode a foreign span, we adjust its 'lo' and 'high' values
458 // to be based on the *foreign* crate (e.g. crate C), not the crate
459 // we are writing metadata for (e.g. crate B). This allows us to
460 // treat the 'local' and 'foreign' cases almost identically during deserialization:
461 // we can call `imported_source_files` for the proper crate, and binary search
462 // through the returned slice using our span.
463 let imported_source_files = if tag == TAG_VALID_SPAN_LOCAL {
464 decoder.cdata().imported_source_files(sess)
466 // When we encode a proc-macro crate, all `Span`s should be encoded
467 // with `TAG_VALID_SPAN_LOCAL`
468 if decoder.cdata().root.is_proc_macro_crate() {
469 // Decode `CrateNum` as u32 - using `CrateNum::decode` will ICE
470 // since we don't have `cnum_map` populated.
471 let cnum = u32::decode(decoder)?;
473 "Decoding of crate {:?} tried to access proc-macro dep {:?}",
474 decoder.cdata().root.name,
478 // tag is TAG_VALID_SPAN_FOREIGN, checked by `debug_assert` above
479 let cnum = CrateNum::decode(decoder)?;
481 "SpecializedDecoder<Span>::specialized_decode: loading source files from cnum {:?}",
485 // Decoding 'foreign' spans should be rare enough that it's
486 // not worth it to maintain a per-CrateNum cache for `last_source_file_index`.
487 // We just set it to 0, to ensure that we don't try to access something out
488 // of bounds for our initial 'guess'
489 decoder.last_source_file_index = 0;
491 let foreign_data = decoder.cdata().cstore.get_crate_data(cnum);
492 foreign_data.imported_source_files(sess)
496 // Optimize for the case that most spans within a translated item
497 // originate from the same source_file.
498 let last_source_file = &imported_source_files[decoder.last_source_file_index];
500 if lo >= last_source_file.original_start_pos && lo <= last_source_file.original_end_pos
504 let index = imported_source_files
505 .binary_search_by_key(&lo, |source_file| source_file.original_start_pos)
506 .unwrap_or_else(|index| index - 1);
508 // Don't try to cache the index for foreign spans,
509 // as this would require a map from CrateNums to indices
510 if tag == TAG_VALID_SPAN_LOCAL {
511 decoder.last_source_file_index = index;
513 &imported_source_files[index]
517 // Make sure our binary search above is correct.
519 lo >= source_file.original_start_pos && lo <= source_file.original_end_pos,
520 "Bad binary search: lo={:?} source_file.original_start_pos={:?} source_file.original_end_pos={:?}",
522 source_file.original_start_pos,
523 source_file.original_end_pos
526 // Make sure we correctly filtered out invalid spans during encoding
528 hi >= source_file.original_start_pos && hi <= source_file.original_end_pos,
529 "Bad binary search: hi={:?} source_file.original_start_pos={:?} source_file.original_end_pos={:?}",
531 source_file.original_start_pos,
532 source_file.original_end_pos
536 (lo + source_file.translated_source_file.start_pos) - source_file.original_start_pos;
538 (hi + source_file.translated_source_file.start_pos) - source_file.original_start_pos;
540 // Do not try to decode parent for foreign spans.
541 Ok(Span::new(lo, hi, ctxt, None))
545 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for &'tcx [thir::abstract_const::Node<'tcx>] {
546 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Result<Self, String> {
547 ty::codec::RefDecodable::decode(d)
551 impl<'a, 'tcx> Decodable<DecodeContext<'a, 'tcx>> for &'tcx [(ty::Predicate<'tcx>, Span)] {
552 fn decode(d: &mut DecodeContext<'a, 'tcx>) -> Result<Self, String> {
553 ty::codec::RefDecodable::decode(d)
557 impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> Decodable<DecodeContext<'a, 'tcx>>
560 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Result<Self, String> {
561 decoder.read_lazy_with_meta(())
565 impl<'a, 'tcx, T: Decodable<DecodeContext<'a, 'tcx>>> Decodable<DecodeContext<'a, 'tcx>>
568 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Result<Self, String> {
569 let len = decoder.read_usize()?;
570 if len == 0 { Ok(Lazy::empty()) } else { decoder.read_lazy_with_meta(len) }
574 impl<'a, 'tcx, I: Idx, T: Decodable<DecodeContext<'a, 'tcx>>> Decodable<DecodeContext<'a, 'tcx>>
575 for Lazy<Table<I, T>>
577 Option<T>: FixedSizeEncoding,
579 fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Result<Self, String> {
580 let len = decoder.read_usize()?;
581 decoder.read_lazy_with_meta(len)
585 implement_ty_decoder!(DecodeContext<'a, 'tcx>);
588 crate fn new(metadata_ref: MetadataRef) -> MetadataBlob {
589 MetadataBlob(metadata_ref)
592 crate fn is_compatible(&self) -> bool {
593 self.raw_bytes().starts_with(METADATA_HEADER)
596 crate fn get_rustc_version(&self) -> String {
597 Lazy::<String>::from_position(NonZeroUsize::new(METADATA_HEADER.len() + 4).unwrap())
601 crate fn get_root(&self) -> CrateRoot<'tcx> {
602 let slice = self.raw_bytes();
603 let offset = METADATA_HEADER.len();
604 let pos = (((slice[offset + 0] as u32) << 24)
605 | ((slice[offset + 1] as u32) << 16)
606 | ((slice[offset + 2] as u32) << 8)
607 | ((slice[offset + 3] as u32) << 0)) as usize;
608 Lazy::<CrateRoot<'tcx>>::from_position(NonZeroUsize::new(pos).unwrap()).decode(self)
611 crate fn list_crate_metadata(&self, out: &mut dyn io::Write) -> io::Result<()> {
612 let root = self.get_root();
613 writeln!(out, "Crate info:")?;
614 writeln!(out, "name {}{}", root.name, root.extra_filename)?;
615 writeln!(out, "hash {} stable_crate_id {:?}", root.hash, root.stable_crate_id)?;
616 writeln!(out, "proc_macro {:?}", root.proc_macro_data.is_some())?;
617 writeln!(out, "=External Dependencies=")?;
618 for (i, dep) in root.crate_deps.decode(self).enumerate() {
621 "{} {}{} hash {} host_hash {:?} kind {:?}",
636 crate fn is_proc_macro_crate(&self) -> bool {
637 self.proc_macro_data.is_some()
640 crate fn name(&self) -> Symbol {
644 crate fn hash(&self) -> Svh {
648 crate fn stable_crate_id(&self) -> StableCrateId {
652 crate fn triple(&self) -> &TargetTriple {
656 crate fn decode_crate_deps(
658 metadata: &'a MetadataBlob,
659 ) -> impl ExactSizeIterator<Item = CrateDep> + Captures<'a> {
660 self.crate_deps.decode(metadata)
664 impl<'a, 'tcx> CrateMetadataRef<'a> {
665 fn raw_proc_macro(&self, id: DefIndex) -> &ProcMacro {
666 // DefIndex's in root.proc_macro_data have a one-to-one correspondence
667 // with items in 'raw_proc_macros'.
675 .position(|i| i == id)
677 &self.raw_proc_macros.unwrap()[pos]
680 fn try_item_ident(&self, item_index: DefIndex, sess: &Session) -> Result<Ident, String> {
686 .ok_or_else(|| format!("Missing opt name for {:?}", item_index))?;
691 .get(self, item_index)
692 .ok_or_else(|| format!("Missing ident span for {:?} ({:?})", name, item_index))?
693 .decode((self, sess));
694 Ok(Ident::new(name, span))
697 fn item_ident(&self, item_index: DefIndex, sess: &Session) -> Ident {
698 self.try_item_ident(item_index, sess).unwrap()
701 fn maybe_kind(&self, item_id: DefIndex) -> Option<EntryKind> {
702 self.root.tables.kind.get(self, item_id).map(|k| k.decode(self))
705 fn kind(&self, item_id: DefIndex) -> EntryKind {
706 self.maybe_kind(item_id).unwrap_or_else(|| {
708 "CrateMetadata::kind({:?}): id not found, in crate {:?} with number {}",
716 fn def_kind(&self, item_id: DefIndex) -> DefKind {
717 self.root.tables.def_kind.get(self, item_id).map(|k| k.decode(self)).unwrap_or_else(|| {
719 "CrateMetadata::def_kind({:?}): id not found, in crate {:?} with number {}",
727 fn get_span(&self, index: DefIndex, sess: &Session) -> Span {
732 .unwrap_or_else(|| panic!("Missing span for {:?}", index))
733 .decode((self, sess))
736 fn load_proc_macro(&self, id: DefIndex, sess: &Session) -> SyntaxExtension {
737 let (name, kind, helper_attrs) = match *self.raw_proc_macro(id) {
738 ProcMacro::CustomDerive { trait_name, attributes, client } => {
740 attributes.iter().cloned().map(Symbol::intern).collect::<Vec<_>>();
743 SyntaxExtensionKind::Derive(Box::new(ProcMacroDerive { client })),
747 ProcMacro::Attr { name, client } => {
748 (name, SyntaxExtensionKind::Attr(Box::new(AttrProcMacro { client })), Vec::new())
750 ProcMacro::Bang { name, client } => {
751 (name, SyntaxExtensionKind::Bang(Box::new(BangProcMacro { client })), Vec::new())
755 let attrs: Vec<_> = self.get_item_attrs(id, sess).collect();
756 SyntaxExtension::new(
759 self.get_span(id, sess),
762 Symbol::intern(name),
767 fn get_trait_def(&self, item_id: DefIndex, sess: &Session) -> ty::TraitDef {
768 match self.kind(item_id) {
769 EntryKind::Trait(data) => {
770 let data = data.decode((self, sess));
772 self.local_def_id(item_id),
777 data.skip_array_during_method_dispatch,
778 data.specialization_kind,
779 self.def_path_hash(item_id),
782 EntryKind::TraitAlias => ty::TraitDef::new(
783 self.local_def_id(item_id),
784 hir::Unsafety::Normal,
789 ty::trait_def::TraitSpecializationKind::None,
790 self.def_path_hash(item_id),
792 _ => bug!("def-index does not refer to trait or trait alias"),
802 ) -> ty::VariantDef {
803 let data = match kind {
804 EntryKind::Variant(data) | EntryKind::Struct(data, _) | EntryKind::Union(data, _) => {
810 let adt_kind = match kind {
811 EntryKind::Variant(_) => ty::AdtKind::Enum,
812 EntryKind::Struct(..) => ty::AdtKind::Struct,
813 EntryKind::Union(..) => ty::AdtKind::Union,
818 if adt_kind == ty::AdtKind::Enum { Some(self.local_def_id(index)) } else { None };
819 let ctor_did = data.ctor.map(|index| self.local_def_id(index));
822 self.item_ident(index, sess),
830 .unwrap_or_else(Lazy::empty)
832 .map(|index| ty::FieldDef {
833 did: self.local_def_id(index),
834 ident: self.item_ident(index, sess),
835 vis: self.get_visibility(index),
842 data.is_non_exhaustive,
846 fn get_adt_def(&self, item_id: DefIndex, tcx: TyCtxt<'tcx>) -> &'tcx ty::AdtDef {
847 let kind = self.kind(item_id);
848 let did = self.local_def_id(item_id);
850 let (adt_kind, repr) = match kind {
851 EntryKind::Enum(repr) => (ty::AdtKind::Enum, repr),
852 EntryKind::Struct(_, repr) => (ty::AdtKind::Struct, repr),
853 EntryKind::Union(_, repr) => (ty::AdtKind::Union, repr),
854 _ => bug!("get_adt_def called on a non-ADT {:?}", did),
857 let variants = if let ty::AdtKind::Enum = adt_kind {
862 .unwrap_or_else(Lazy::empty)
864 .map(|index| self.get_variant(&self.kind(index), index, did, tcx.sess))
867 std::iter::once(self.get_variant(&kind, item_id, did, tcx.sess)).collect()
870 tcx.alloc_adt_def(did, adt_kind, variants, repr)
873 fn get_explicit_predicates(
877 ) -> ty::GenericPredicates<'tcx> {
878 self.root.tables.explicit_predicates.get(self, item_id).unwrap().decode((self, tcx))
881 fn get_inferred_outlives(
885 ) -> &'tcx [(ty::Predicate<'tcx>, Span)] {
890 .map(|predicates| tcx.arena.alloc_from_iter(predicates.decode((self, tcx))))
894 fn get_super_predicates(
898 ) -> ty::GenericPredicates<'tcx> {
899 self.root.tables.super_predicates.get(self, item_id).unwrap().decode((self, tcx))
902 fn get_explicit_item_bounds(
906 ) -> &'tcx [(ty::Predicate<'tcx>, Span)] {
909 .explicit_item_bounds
911 .map(|bounds| tcx.arena.alloc_from_iter(bounds.decode((self, tcx))))
915 fn get_generics(&self, item_id: DefIndex, sess: &Session) -> ty::Generics {
916 self.root.tables.generics.get(self, item_id).unwrap().decode((self, sess))
919 fn get_type(&self, id: DefIndex, tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
924 .unwrap_or_else(|| panic!("Not a type: {:?}", id))
928 fn get_stability(&self, id: DefIndex) -> Option<attr::Stability> {
929 self.root.tables.stability.get(self, id).map(|stab| stab.decode(self))
932 fn get_const_stability(&self, id: DefIndex) -> Option<attr::ConstStability> {
933 self.root.tables.const_stability.get(self, id).map(|stab| stab.decode(self))
936 fn get_deprecation(&self, id: DefIndex) -> Option<attr::Deprecation> {
937 self.root.tables.deprecation.get(self, id).map(|depr| depr.decode(self))
940 fn get_visibility(&self, id: DefIndex) -> ty::Visibility {
941 self.root.tables.visibility.get(self, id).unwrap().decode(self)
944 fn get_impl_data(&self, id: DefIndex) -> ImplData {
945 match self.kind(id) {
946 EntryKind::Impl(data) => data.decode(self),
951 fn get_parent_impl(&self, id: DefIndex) -> Option<DefId> {
952 self.get_impl_data(id).parent_impl
955 fn get_impl_polarity(&self, id: DefIndex) -> ty::ImplPolarity {
956 self.get_impl_data(id).polarity
959 fn get_impl_defaultness(&self, id: DefIndex) -> hir::Defaultness {
960 self.get_impl_data(id).defaultness
963 fn get_impl_constness(&self, id: DefIndex) -> hir::Constness {
964 self.get_impl_data(id).constness
967 fn get_coerce_unsized_info(&self, id: DefIndex) -> Option<ty::adjustment::CoerceUnsizedInfo> {
968 self.get_impl_data(id).coerce_unsized_info
971 fn get_impl_trait(&self, id: DefIndex, tcx: TyCtxt<'tcx>) -> Option<ty::TraitRef<'tcx>> {
972 self.root.tables.impl_trait_ref.get(self, id).map(|tr| tr.decode((self, tcx)))
975 fn get_expn_that_defined(&self, id: DefIndex, sess: &Session) -> ExpnId {
976 self.root.tables.expn_that_defined.get(self, id).unwrap().decode((self, sess))
979 fn get_const_param_default(
983 ) -> rustc_middle::ty::Const<'tcx> {
984 self.root.tables.const_defaults.get(self, id).unwrap().decode((self, tcx))
987 /// Iterates over all the stability attributes in the given crate.
988 fn get_lib_features(&self, tcx: TyCtxt<'tcx>) -> &'tcx [(Symbol, Option<Symbol>)] {
989 // FIXME: For a proc macro crate, not sure whether we should return the "host"
990 // features or an empty Vec. Both don't cause ICEs.
991 tcx.arena.alloc_from_iter(self.root.lib_features.decode(self))
994 /// Iterates over the language items in the given crate.
995 fn get_lang_items(&self, tcx: TyCtxt<'tcx>) -> &'tcx [(DefId, usize)] {
996 if self.root.is_proc_macro_crate() {
997 // Proc macro crates do not export any lang-items to the target.
1000 tcx.arena.alloc_from_iter(
1004 .map(|(def_index, index)| (self.local_def_id(def_index), index)),
1009 /// Iterates over the diagnostic items in the given crate.
1010 fn get_diagnostic_items(&self) -> FxHashMap<Symbol, DefId> {
1011 if self.root.is_proc_macro_crate() {
1012 // Proc macro crates do not export any diagnostic-items to the target.
1018 .map(|(name, def_index)| (name, self.local_def_id(def_index)))
1023 /// Iterates over each child of the given item.
1024 fn each_child_of_item(&self, id: DefIndex, mut callback: impl FnMut(Export), sess: &Session) {
1025 if let Some(data) = &self.root.proc_macro_data {
1026 /* If we are loading as a proc macro, we want to return the view of this crate
1027 * as a proc macro crate.
1029 if id == CRATE_DEF_INDEX {
1030 let macros = data.macros.decode(self);
1031 for def_index in macros {
1032 let raw_macro = self.raw_proc_macro(def_index);
1034 DefKind::Macro(macro_kind(raw_macro)),
1035 self.local_def_id(def_index),
1037 let ident = self.item_ident(def_index, sess);
1038 callback(Export { ident, res, vis: ty::Visibility::Public, span: ident.span });
1045 let kind = match self.maybe_kind(id) {
1050 // Iterate over all children.
1051 let macros_only = self.dep_kind.lock().macros_only();
1053 let children = self.root.tables.children.get(self, id).unwrap_or_else(Lazy::empty);
1055 for child_index in children.decode((self, sess)) {
1057 let child_kind = match self.maybe_kind(child_index) {
1058 Some(child_kind) => child_kind,
1062 // Hand off the item to the callback.
1064 // FIXME(eddyb) Don't encode these in children.
1065 EntryKind::ForeignMod => {
1066 let child_children = self
1070 .get(self, child_index)
1071 .unwrap_or_else(Lazy::empty);
1072 for child_index in child_children.decode((self, sess)) {
1073 let kind = self.def_kind(child_index);
1075 res: Res::Def(kind, self.local_def_id(child_index)),
1076 ident: self.item_ident(child_index, sess),
1077 vis: self.get_visibility(child_index),
1082 .get(self, child_index)
1084 .decode((self, sess)),
1089 EntryKind::Impl(_) => continue,
1094 let def_key = self.def_key(child_index);
1095 if def_key.disambiguated_data.data.get_opt_name().is_some() {
1096 let span = self.get_span(child_index, sess);
1097 let kind = self.def_kind(child_index);
1098 let ident = self.item_ident(child_index, sess);
1099 let vis = self.get_visibility(child_index);
1100 let def_id = self.local_def_id(child_index);
1101 let res = Res::Def(kind, def_id);
1103 // FIXME: Macros are currently encoded twice, once as items and once as
1104 // reexports. We ignore the items here and only use the reexports.
1105 if !matches!(kind, DefKind::Macro(..)) {
1106 callback(Export { res, ident, vis, span });
1109 // For non-re-export structs and variants add their constructors to children.
1110 // Re-export lists automatically contain constructors when necessary.
1112 DefKind::Struct => {
1113 if let Some(ctor_def_id) = self.get_ctor_def_id(child_index) {
1114 let ctor_kind = self.get_ctor_kind(child_index);
1116 Res::Def(DefKind::Ctor(CtorOf::Struct, ctor_kind), ctor_def_id);
1117 let vis = self.get_visibility(ctor_def_id.index);
1118 callback(Export { res: ctor_res, vis, ident, span });
1121 DefKind::Variant => {
1122 // Braced variants, unlike structs, generate unusable names in
1123 // value namespace, they are reserved for possible future use.
1124 // It's ok to use the variant's id as a ctor id since an
1125 // error will be reported on any use of such resolution anyway.
1126 let ctor_def_id = self.get_ctor_def_id(child_index).unwrap_or(def_id);
1127 let ctor_kind = self.get_ctor_kind(child_index);
1129 Res::Def(DefKind::Ctor(CtorOf::Variant, ctor_kind), ctor_def_id);
1130 let mut vis = self.get_visibility(ctor_def_id.index);
1131 if ctor_def_id == def_id && vis == ty::Visibility::Public {
1132 // For non-exhaustive variants lower the constructor visibility to
1133 // within the crate. We only need this for fictive constructors,
1134 // for other constructors correct visibilities
1135 // were already encoded in metadata.
1136 let mut attrs = self.get_item_attrs(def_id.index, sess);
1137 if attrs.any(|item| item.has_name(sym::non_exhaustive)) {
1138 let crate_def_id = self.local_def_id(CRATE_DEF_INDEX);
1139 vis = ty::Visibility::Restricted(crate_def_id);
1142 callback(Export { res: ctor_res, ident, vis, span });
1150 if let EntryKind::Mod(data) = kind {
1151 for exp in data.decode((self, sess)).reexports.decode((self, sess)) {
1153 Res::Def(DefKind::Macro(..), _) => {}
1154 _ if macros_only => continue,
1162 fn is_ctfe_mir_available(&self, id: DefIndex) -> bool {
1163 self.root.tables.mir_for_ctfe.get(self, id).is_some()
1166 fn is_item_mir_available(&self, id: DefIndex) -> bool {
1167 self.root.tables.mir.get(self, id).is_some()
1170 fn module_expansion(&self, id: DefIndex, sess: &Session) -> ExpnId {
1171 if let EntryKind::Mod(m) = self.kind(id) {
1172 m.decode((self, sess)).expansion
1174 panic!("Expected module, found {:?}", self.local_def_id(id))
1178 fn get_optimized_mir(&self, tcx: TyCtxt<'tcx>, id: DefIndex) -> Body<'tcx> {
1183 .unwrap_or_else(|| {
1184 bug!("get_optimized_mir: missing MIR for `{:?}`", self.local_def_id(id))
1186 .decode((self, tcx))
1189 fn get_mir_for_ctfe(&self, tcx: TyCtxt<'tcx>, id: DefIndex) -> Body<'tcx> {
1194 .unwrap_or_else(|| {
1195 bug!("get_mir_for_ctfe: missing MIR for `{:?}`", self.local_def_id(id))
1197 .decode((self, tcx))
1200 fn get_thir_abstract_const(
1204 ) -> Result<Option<&'tcx [thir::abstract_const::Node<'tcx>]>, ErrorReported> {
1207 .thir_abstract_consts
1209 .map_or(Ok(None), |v| Ok(Some(v.decode((self, tcx)))))
1212 fn get_unused_generic_params(&self, id: DefIndex) -> FiniteBitSet<u32> {
1215 .unused_generic_params
1217 .map(|params| params.decode(self))
1218 .unwrap_or_default()
1221 fn get_promoted_mir(&self, tcx: TyCtxt<'tcx>, id: DefIndex) -> IndexVec<Promoted, Body<'tcx>> {
1226 .unwrap_or_else(|| {
1227 bug!("get_promoted_mir: missing MIR for `{:?}`", self.local_def_id(id))
1229 .decode((self, tcx))
1232 fn mir_const_qualif(&self, id: DefIndex) -> mir::ConstQualifs {
1233 match self.kind(id) {
1234 EntryKind::AnonConst(qualif, _)
1235 | EntryKind::Const(qualif, _)
1236 | EntryKind::AssocConst(
1237 AssocContainer::ImplDefault
1238 | AssocContainer::ImplFinal
1239 | AssocContainer::TraitWithDefault,
1243 _ => bug!("mir_const_qualif: unexpected kind"),
1247 fn get_associated_item(&self, id: DefIndex, sess: &Session) -> ty::AssocItem {
1248 let def_key = self.def_key(id);
1249 let parent = self.local_def_id(def_key.parent.unwrap());
1250 let ident = self.item_ident(id, sess);
1252 let (kind, container, has_self) = match self.kind(id) {
1253 EntryKind::AssocConst(container, _, _) => (ty::AssocKind::Const, container, false),
1254 EntryKind::AssocFn(data) => {
1255 let data = data.decode(self);
1256 (ty::AssocKind::Fn, data.container, data.has_self)
1258 EntryKind::AssocType(container) => (ty::AssocKind::Type, container, false),
1259 _ => bug!("cannot get associated-item of `{:?}`", def_key),
1265 vis: self.get_visibility(id),
1266 defaultness: container.defaultness(),
1267 def_id: self.local_def_id(id),
1268 container: container.with_def_id(parent),
1269 fn_has_self_parameter: has_self,
1273 fn get_item_variances(&'a self, id: DefIndex) -> impl Iterator<Item = ty::Variance> + 'a {
1274 self.root.tables.variances.get(self, id).unwrap_or_else(Lazy::empty).decode(self)
1277 fn get_ctor_kind(&self, node_id: DefIndex) -> CtorKind {
1278 match self.kind(node_id) {
1279 EntryKind::Struct(data, _) | EntryKind::Union(data, _) | EntryKind::Variant(data) => {
1280 data.decode(self).ctor_kind
1282 _ => CtorKind::Fictive,
1286 fn get_ctor_def_id(&self, node_id: DefIndex) -> Option<DefId> {
1287 match self.kind(node_id) {
1288 EntryKind::Struct(data, _) => {
1289 data.decode(self).ctor.map(|index| self.local_def_id(index))
1291 EntryKind::Variant(data) => {
1292 data.decode(self).ctor.map(|index| self.local_def_id(index))
1302 ) -> impl Iterator<Item = ast::Attribute> + 'a {
1303 // The attributes for a tuple struct/variant are attached to the definition, not the ctor;
1304 // we assume that someone passing in a tuple struct ctor is actually wanting to
1305 // look at the definition
1306 let def_key = self.def_key(node_id);
1307 let item_id = if def_key.disambiguated_data.data == DefPathData::Ctor {
1308 def_key.parent.unwrap()
1317 .unwrap_or_else(Lazy::empty)
1318 .decode((self, sess))
1321 fn get_struct_field_names(&self, id: DefIndex, sess: &Session) -> Vec<Spanned<Symbol>> {
1326 .unwrap_or_else(Lazy::empty)
1328 .map(|index| respan(self.get_span(index, sess), self.item_ident(index, sess).name))
1332 fn get_struct_field_visibilities(&self, id: DefIndex) -> Vec<Visibility> {
1337 .unwrap_or_else(Lazy::empty)
1339 .map(|field_index| self.get_visibility(field_index))
1343 fn get_inherent_implementations_for_type(
1347 ) -> &'tcx [DefId] {
1348 tcx.arena.alloc_from_iter(
1353 .unwrap_or_else(Lazy::empty)
1355 .map(|index| self.local_def_id(index)),
1359 fn get_implementations_for_trait(
1362 filter: Option<DefId>,
1363 ) -> &'tcx [(DefId, Option<ty::fast_reject::SimplifiedType>)] {
1364 if self.root.is_proc_macro_crate() {
1365 // proc-macro crates export no trait impls.
1369 if let Some(def_id) = filter {
1370 // Do a reverse lookup beforehand to avoid touching the crate_num
1371 // hash map in the loop below.
1372 let filter = match self.reverse_translate_def_id(def_id) {
1373 Some(def_id) => (def_id.krate.as_u32(), def_id.index),
1377 if let Some(impls) = self.trait_impls.get(&filter) {
1378 tcx.arena.alloc_from_iter(
1379 impls.decode(self).map(|(idx, simplified_self_ty)| {
1380 (self.local_def_id(idx), simplified_self_ty)
1387 tcx.arena.alloc_from_iter(self.trait_impls.values().flat_map(|impls| {
1390 .map(|(idx, simplified_self_ty)| (self.local_def_id(idx), simplified_self_ty))
1395 fn get_trait_of_item(&self, id: DefIndex) -> Option<DefId> {
1396 let def_key = self.def_key(id);
1397 match def_key.disambiguated_data.data {
1398 DefPathData::TypeNs(..) | DefPathData::ValueNs(..) => (),
1399 // Not an associated item
1402 def_key.parent.and_then(|parent_index| match self.kind(parent_index) {
1403 EntryKind::Trait(_) | EntryKind::TraitAlias => Some(self.local_def_id(parent_index)),
1408 fn get_native_libraries(&self, sess: &Session) -> Vec<NativeLib> {
1409 if self.root.is_proc_macro_crate() {
1410 // Proc macro crates do not have any *target* native libraries.
1413 self.root.native_libraries.decode((self, sess)).collect()
1417 fn get_proc_macro_quoted_span(&self, index: usize, sess: &Session) -> Span {
1420 .proc_macro_quoted_spans
1422 .unwrap_or_else(|| panic!("Missing proc macro quoted span: {:?}", index))
1423 .decode((self, sess))
1426 fn get_foreign_modules(&self, tcx: TyCtxt<'tcx>) -> Lrc<FxHashMap<DefId, ForeignModule>> {
1427 if self.root.is_proc_macro_crate() {
1428 // Proc macro crates do not have any *target* foreign modules.
1429 Lrc::new(FxHashMap::default())
1431 let modules: FxHashMap<DefId, ForeignModule> =
1432 self.root.foreign_modules.decode((self, tcx.sess)).map(|m| (m.def_id, m)).collect();
1437 fn get_dylib_dependency_formats(
1440 ) -> &'tcx [(CrateNum, LinkagePreference)] {
1441 tcx.arena.alloc_from_iter(
1442 self.root.dylib_dependency_formats.decode(self).enumerate().flat_map(|(i, link)| {
1443 let cnum = CrateNum::new(i + 1);
1444 link.map(|link| (self.cnum_map[cnum], link))
1449 fn get_missing_lang_items(&self, tcx: TyCtxt<'tcx>) -> &'tcx [lang_items::LangItem] {
1450 if self.root.is_proc_macro_crate() {
1451 // Proc macro crates do not depend on any target weak lang-items.
1454 tcx.arena.alloc_from_iter(self.root.lang_items_missing.decode(self))
1458 fn get_fn_param_names(&self, tcx: TyCtxt<'tcx>, id: DefIndex) -> &'tcx [Ident] {
1459 let param_names = match self.kind(id) {
1460 EntryKind::Fn(data) | EntryKind::ForeignFn(data) => data.decode(self).param_names,
1461 EntryKind::AssocFn(data) => data.decode(self).fn_data.param_names,
1464 tcx.arena.alloc_from_iter(param_names.decode((self, tcx)))
1467 fn exported_symbols(
1470 ) -> &'tcx [(ExportedSymbol<'tcx>, SymbolExportLevel)] {
1471 if self.root.is_proc_macro_crate() {
1472 // If this crate is a custom derive crate, then we're not even going to
1473 // link those in so we skip those crates.
1476 tcx.arena.alloc_from_iter(self.root.exported_symbols.decode((self, tcx)))
1480 fn get_rendered_const(&self, id: DefIndex) -> String {
1481 match self.kind(id) {
1482 EntryKind::AnonConst(_, data)
1483 | EntryKind::Const(_, data)
1484 | EntryKind::AssocConst(_, _, data) => data.decode(self).0,
1489 fn get_macro(&self, id: DefIndex, sess: &Session) -> MacroDef {
1490 match self.kind(id) {
1491 EntryKind::MacroDef(macro_def) => macro_def.decode((self, sess)),
1496 // This replicates some of the logic of the crate-local `is_const_fn_raw` query, because we
1497 // don't serialize constness for tuple variant and tuple struct constructors.
1498 fn is_const_fn_raw(&self, id: DefIndex) -> bool {
1499 let constness = match self.kind(id) {
1500 EntryKind::AssocFn(data) => data.decode(self).fn_data.constness,
1501 EntryKind::Fn(data) => data.decode(self).constness,
1502 EntryKind::ForeignFn(data) => data.decode(self).constness,
1503 EntryKind::Variant(..) | EntryKind::Struct(..) => hir::Constness::Const,
1504 _ => hir::Constness::NotConst,
1506 constness == hir::Constness::Const
1509 fn asyncness(&self, id: DefIndex) -> hir::IsAsync {
1510 match self.kind(id) {
1511 EntryKind::Fn(data) => data.decode(self).asyncness,
1512 EntryKind::AssocFn(data) => data.decode(self).fn_data.asyncness,
1513 EntryKind::ForeignFn(data) => data.decode(self).asyncness,
1514 _ => bug!("asyncness: expected function kind"),
1518 fn is_foreign_item(&self, id: DefIndex) -> bool {
1519 match self.kind(id) {
1520 EntryKind::ForeignImmStatic | EntryKind::ForeignMutStatic | EntryKind::ForeignFn(_) => {
1527 fn static_mutability(&self, id: DefIndex) -> Option<hir::Mutability> {
1528 match self.kind(id) {
1529 EntryKind::ImmStatic | EntryKind::ForeignImmStatic => Some(hir::Mutability::Not),
1530 EntryKind::MutStatic | EntryKind::ForeignMutStatic => Some(hir::Mutability::Mut),
1535 fn generator_kind(&self, id: DefIndex) -> Option<hir::GeneratorKind> {
1536 match self.kind(id) {
1537 EntryKind::Generator(data) => Some(data),
1542 fn fn_sig(&self, id: DefIndex, tcx: TyCtxt<'tcx>) -> ty::PolyFnSig<'tcx> {
1543 self.root.tables.fn_sig.get(self, id).unwrap().decode((self, tcx))
1547 fn def_key(&self, index: DefIndex) -> DefKey {
1552 .or_insert_with(|| self.root.tables.def_keys.get(self, index).unwrap().decode(self))
1555 /// Finds the corresponding `DefId` for the provided `DefPathHash`, if it exists.
1556 /// This is used by incremental compilation to map a serialized `DefPathHash` to
1557 /// its `DefId` in the current session.
1558 /// Normally, only one 'main' crate will change between incremental compilation sessions:
1559 /// all dependencies will be completely unchanged. In this case, we can avoid
1560 /// decoding every `DefPathHash` in the crate, since the `DefIndex` from the previous
1561 /// session will still be valid. If our 'guess' is wrong (the `DefIndex` no longer exists,
1562 /// or has a different `DefPathHash`, then we need to decode all `DefPathHashes` to determine
1563 /// the correct mapping).
1564 fn def_path_hash_to_def_id(
1569 ) -> Option<DefId> {
1570 let def_index_guess = DefIndex::from_u32(index_guess);
1575 .get(self, def_index_guess)
1576 .map(|lazy| lazy.decode(self));
1578 // Fast path: the definition and its index is unchanged from the
1579 // previous compilation session. There is no need to decode anything
1581 if old_hash == Some(hash) {
1582 return Some(DefId { krate, index: def_index_guess });
1585 let is_proc_macro = self.is_proc_macro_crate();
1587 // Slow path: We need to find out the new `DefIndex` of the provided
1588 // `DefPathHash`, if its still exists. This requires decoding every `DefPathHash`
1589 // stored in this crate.
1590 let map = self.cdata.def_path_hash_map.get_or_init(|| {
1591 let end_id = self.root.tables.def_path_hashes.size() as u32;
1592 let mut map = UnhashMap::with_capacity_and_hasher(end_id as usize, Default::default());
1593 for i in 0..end_id {
1594 let def_index = DefIndex::from_u32(i);
1595 // There may be gaps in the encoded table if we're decoding a proc-macro crate
1596 if let Some(hash) = self.root.tables.def_path_hashes.get(self, def_index) {
1597 map.insert(hash.decode(self), def_index);
1598 } else if !is_proc_macro {
1599 panic!("Missing def_path_hashes entry for {:?}", def_index);
1604 map.get(&hash).map(|index| DefId { krate, index: *index })
1607 // Returns the path leading to the thing with this `id`.
1608 fn def_path(&self, id: DefIndex) -> DefPath {
1609 debug!("def_path(cnum={:?}, id={:?})", self.cnum, id);
1610 DefPath::make(self.cnum, id, |parent| self.def_key(parent))
1613 fn def_path_hash_unlocked(
1616 def_path_hashes: &mut FxHashMap<DefIndex, DefPathHash>,
1618 *def_path_hashes.entry(index).or_insert_with(|| {
1619 self.root.tables.def_path_hashes.get(self, index).unwrap().decode(self)
1624 fn def_path_hash(&self, index: DefIndex) -> DefPathHash {
1625 let mut def_path_hashes = self.def_path_hash_cache.lock();
1626 self.def_path_hash_unlocked(index, &mut def_path_hashes)
1629 fn expn_hash_to_expn_id(&self, index_guess: u32, hash: ExpnHash) -> ExpnId {
1630 debug_assert_eq!(ExpnId::from_hash(hash), None);
1631 let index_guess = ExpnIndex::from_u32(index_guess);
1632 let old_hash = self.root.expn_hashes.get(self, index_guess).map(|lazy| lazy.decode(self));
1634 let index = if old_hash == Some(hash) {
1635 // Fast path: the expn and its index is unchanged from the
1636 // previous compilation session. There is no need to decode anything
1640 // Slow path: We need to find out the new `DefIndex` of the provided
1641 // `DefPathHash`, if its still exists. This requires decoding every `DefPathHash`
1642 // stored in this crate.
1643 let map = self.cdata.expn_hash_map.get_or_init(|| {
1644 let end_id = self.root.expn_hashes.size() as u32;
1646 UnhashMap::with_capacity_and_hasher(end_id as usize, Default::default());
1647 for i in 0..end_id {
1648 let i = ExpnIndex::from_u32(i);
1649 if let Some(hash) = self.root.expn_hashes.get(self, i) {
1650 map.insert(hash.decode(self), i);
1652 panic!("Missing expn_hash entry for {:?}", i);
1660 let data = self.root.expn_data.get(self, index).unwrap().decode(self);
1661 rustc_span::hygiene::register_expn_id(self.cnum, index, data, hash)
1664 /// Imports the source_map from an external crate into the source_map of the crate
1665 /// currently being compiled (the "local crate").
1667 /// The import algorithm works analogous to how AST items are inlined from an
1668 /// external crate's metadata:
1669 /// For every SourceFile in the external source_map an 'inline' copy is created in the
1670 /// local source_map. The correspondence relation between external and local
1671 /// SourceFiles is recorded in the `ImportedSourceFile` objects returned from this
1672 /// function. When an item from an external crate is later inlined into this
1673 /// crate, this correspondence information is used to translate the span
1674 /// information of the inlined item so that it refers the correct positions in
1675 /// the local source_map (see `<decoder::DecodeContext as SpecializedDecoder<Span>>`).
1677 /// The import algorithm in the function below will reuse SourceFiles already
1678 /// existing in the local source_map. For example, even if the SourceFile of some
1679 /// source file of libstd gets imported many times, there will only ever be
1680 /// one SourceFile object for the corresponding file in the local source_map.
1682 /// Note that imported SourceFiles do not actually contain the source code of the
1683 /// file they represent, just information about length, line breaks, and
1684 /// multibyte characters. This information is enough to generate valid debuginfo
1685 /// for items inlined from other crates.
1687 /// Proc macro crates don't currently export spans, so this function does not have
1688 /// to work for them.
1689 fn imported_source_files(&self, sess: &Session) -> &'a [ImportedSourceFile] {
1690 // Translate the virtual `/rustc/$hash` prefix back to a real directory
1691 // that should hold actual sources, where possible.
1693 // NOTE: if you update this, you might need to also update bootstrap's code for generating
1694 // the `rust-src` component in `Src::run` in `src/bootstrap/dist.rs`.
1695 let virtual_rust_source_base_dir = option_env!("CFG_VIRTUAL_RUST_SOURCE_BASE_DIR")
1698 // Only spend time on further checks if we have what to translate *to*.
1699 sess.opts.real_rust_source_base_dir.is_some()
1701 .filter(|virtual_dir| {
1702 // Don't translate away `/rustc/$hash` if we're still remapping to it,
1703 // since that means we're still building `std`/`rustc` that need it,
1704 // and we don't want the real path to leak into codegen/debuginfo.
1705 !sess.opts.remap_path_prefix.iter().any(|(_from, to)| to == virtual_dir)
1707 let try_to_translate_virtual_to_real = |name: &mut rustc_span::FileName| {
1709 "try_to_translate_virtual_to_real(name={:?}): \
1710 virtual_rust_source_base_dir={:?}, real_rust_source_base_dir={:?}",
1711 name, virtual_rust_source_base_dir, sess.opts.real_rust_source_base_dir,
1714 if let Some(virtual_dir) = virtual_rust_source_base_dir {
1715 if let Some(real_dir) = &sess.opts.real_rust_source_base_dir {
1716 if let rustc_span::FileName::Real(old_name) = name {
1717 if let rustc_span::RealFileName::Remapped { local_path: _, virtual_name } =
1720 if let Ok(rest) = virtual_name.strip_prefix(virtual_dir) {
1721 let virtual_name = virtual_name.clone();
1723 // The std library crates are in
1724 // `$sysroot/lib/rustlib/src/rust/library`, whereas other crates
1725 // may be in `$sysroot/lib/rustlib/src/rust/` directly. So we
1726 // detect crates from the std libs and handle them specially.
1727 const STD_LIBS: &[&str] = &[
1737 "profiler_builtins",
1739 "rustc-std-workspace-core",
1740 "rustc-std-workspace-alloc",
1741 "rustc-std-workspace-std",
1744 let is_std_lib = STD_LIBS.iter().any(|l| rest.starts_with(l));
1746 let new_path = if is_std_lib {
1747 real_dir.join("library").join(rest)
1753 "try_to_translate_virtual_to_real: `{}` -> `{}`",
1754 virtual_name.display(),
1757 let new_name = rustc_span::RealFileName::Remapped {
1758 local_path: Some(new_path),
1761 *old_name = new_name;
1769 self.cdata.source_map_import_info.get_or_init(|| {
1770 let external_source_map = self.root.source_map.decode(self);
1773 .map(|source_file_to_import| {
1774 // We can't reuse an existing SourceFile, so allocate a new one
1775 // containing the information we need.
1776 let rustc_span::SourceFile {
1782 mut multibyte_chars,
1783 mut non_narrow_chars,
1787 } = source_file_to_import;
1789 // If this file is under $sysroot/lib/rustlib/src/ but has not been remapped
1790 // during rust bootstrapping by `remap-debuginfo = true`, and the user
1791 // wish to simulate that behaviour by -Z simulate-remapped-rust-src-base,
1792 // then we change `name` to a similar state as if the rust was bootstrapped
1793 // with `remap-debuginfo = true`.
1794 // This is useful for testing so that tests about the effects of
1795 // `try_to_translate_virtual_to_real` don't have to worry about how the
1796 // compiler is bootstrapped.
1797 if let Some(virtual_dir) =
1798 &sess.opts.debugging_opts.simulate_remapped_rust_src_base
1800 if let Some(real_dir) = &sess.opts.real_rust_source_base_dir {
1801 if let rustc_span::FileName::Real(ref mut old_name) = name {
1802 if let rustc_span::RealFileName::LocalPath(local) = old_name {
1803 if let Ok(rest) = local.strip_prefix(real_dir) {
1804 *old_name = rustc_span::RealFileName::Remapped {
1806 virtual_name: virtual_dir.join(rest),
1814 // If this file's path has been remapped to `/rustc/$hash`,
1815 // we might be able to reverse that (also see comments above,
1816 // on `try_to_translate_virtual_to_real`).
1817 try_to_translate_virtual_to_real(&mut name);
1819 let source_length = (end_pos - start_pos).to_usize();
1821 // Translate line-start positions and multibyte character
1822 // position into frame of reference local to file.
1823 // `SourceMap::new_imported_source_file()` will then translate those
1824 // coordinates to their new global frame of reference when the
1825 // offset of the SourceFile is known.
1826 for pos in &mut lines {
1827 *pos = *pos - start_pos;
1829 for mbc in &mut multibyte_chars {
1830 mbc.pos = mbc.pos - start_pos;
1832 for swc in &mut non_narrow_chars {
1833 *swc = *swc - start_pos;
1835 for np in &mut normalized_pos {
1836 np.pos = np.pos - start_pos;
1839 let local_version = sess.source_map().new_imported_source_file(
1853 "CrateMetaData::imported_source_files alloc \
1854 source_file {:?} original (start_pos {:?} end_pos {:?}) \
1855 translated (start_pos {:?} end_pos {:?})",
1859 local_version.start_pos,
1860 local_version.end_pos
1863 ImportedSourceFile {
1864 original_start_pos: start_pos,
1865 original_end_pos: end_pos,
1866 translated_source_file: local_version,
1874 impl CrateMetadata {
1878 root: CrateRoot<'static>,
1879 raw_proc_macros: Option<&'static [ProcMacro]>,
1881 cnum_map: CrateNumMap,
1882 dep_kind: CrateDepKind,
1883 source: CrateSource,
1885 host_hash: Option<Svh>,
1886 ) -> CrateMetadata {
1887 let trait_impls = root
1889 .decode((&blob, sess))
1890 .map(|trait_impls| (trait_impls.trait_id, trait_impls.impls))
1892 let alloc_decoding_state =
1893 AllocDecodingState::new(root.interpret_alloc_index.decode(&blob).collect());
1894 let dependencies = Lock::new(cnum_map.iter().cloned().collect());
1900 source_map_import_info: OnceCell::new(),
1901 def_path_hash_map: Default::default(),
1902 expn_hash_map: Default::default(),
1903 alloc_decoding_state,
1907 dep_kind: Lock::new(dep_kind),
1911 extern_crate: Lock::new(None),
1912 hygiene_context: Default::default(),
1913 def_key_cache: Default::default(),
1914 def_path_hash_cache: Default::default(),
1918 crate fn dependencies(&self) -> LockGuard<'_, Vec<CrateNum>> {
1919 self.dependencies.borrow()
1922 crate fn add_dependency(&self, cnum: CrateNum) {
1923 self.dependencies.borrow_mut().push(cnum);
1926 crate fn update_extern_crate(&self, new_extern_crate: ExternCrate) -> bool {
1927 let mut extern_crate = self.extern_crate.borrow_mut();
1928 let update = Some(new_extern_crate.rank()) > extern_crate.as_ref().map(ExternCrate::rank);
1930 *extern_crate = Some(new_extern_crate);
1935 crate fn source(&self) -> &CrateSource {
1939 crate fn dep_kind(&self) -> CrateDepKind {
1940 *self.dep_kind.lock()
1943 crate fn update_dep_kind(&self, f: impl FnOnce(CrateDepKind) -> CrateDepKind) {
1944 self.dep_kind.with_lock(|dep_kind| *dep_kind = f(*dep_kind))
1947 crate fn panic_strategy(&self) -> PanicStrategy {
1948 self.root.panic_strategy
1951 crate fn needs_panic_runtime(&self) -> bool {
1952 self.root.needs_panic_runtime
1955 crate fn is_panic_runtime(&self) -> bool {
1956 self.root.panic_runtime
1959 crate fn is_profiler_runtime(&self) -> bool {
1960 self.root.profiler_runtime
1963 crate fn needs_allocator(&self) -> bool {
1964 self.root.needs_allocator
1967 crate fn has_global_allocator(&self) -> bool {
1968 self.root.has_global_allocator
1971 crate fn has_default_lib_allocator(&self) -> bool {
1972 self.root.has_default_lib_allocator
1975 crate fn is_proc_macro_crate(&self) -> bool {
1976 self.root.is_proc_macro_crate()
1979 crate fn name(&self) -> Symbol {
1983 crate fn stable_crate_id(&self) -> StableCrateId {
1984 self.root.stable_crate_id
1987 crate fn hash(&self) -> Svh {
1991 fn num_def_ids(&self) -> usize {
1992 self.root.tables.def_keys.size()
1995 fn local_def_id(&self, index: DefIndex) -> DefId {
1996 DefId { krate: self.cnum, index }
1999 // Translate a DefId from the current compilation environment to a DefId
2000 // for an external crate.
2001 fn reverse_translate_def_id(&self, did: DefId) -> Option<DefId> {
2002 for (local, &global) in self.cnum_map.iter_enumerated() {
2003 if global == did.krate {
2004 return Some(DefId { krate: local, index: did.index });
2012 // Cannot be implemented on 'ProcMacro', as libproc_macro
2013 // does not depend on librustc_ast
2014 fn macro_kind(raw: &ProcMacro) -> MacroKind {
2016 ProcMacro::CustomDerive { .. } => MacroKind::Derive,
2017 ProcMacro::Attr { .. } => MacroKind::Attr,
2018 ProcMacro::Bang { .. } => MacroKind::Bang,