1 use crate::errors::{FailCreateFileEncoder, FailSeekFile, FailWriteFile};
2 use crate::rmeta::def_path_hash_map::DefPathHashMapRef;
3 use crate::rmeta::table::TableBuilder;
6 use rustc_data_structures::fingerprint::Fingerprint;
7 use rustc_data_structures::fx::{FxHashMap, FxIndexSet};
8 use rustc_data_structures::memmap::{Mmap, MmapMut};
9 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
10 use rustc_data_structures::sync::{join, par_iter, Lrc, ParallelIterator};
11 use rustc_data_structures::temp_dir::MaybeTempDir;
13 use rustc_hir::def::DefKind;
14 use rustc_hir::def_id::{
15 CrateNum, DefId, DefIndex, LocalDefId, CRATE_DEF_ID, CRATE_DEF_INDEX, LOCAL_CRATE,
17 use rustc_hir::definitions::DefPathData;
18 use rustc_hir::intravisit::{self, Visitor};
19 use rustc_hir::lang_items;
20 use rustc_middle::hir::nested_filter;
21 use rustc_middle::middle::dependency_format::Linkage;
22 use rustc_middle::middle::exported_symbols::{
23 metadata_symbol_name, ExportedSymbol, SymbolExportInfo,
25 use rustc_middle::mir::interpret;
26 use rustc_middle::traits::specialization_graph;
27 use rustc_middle::ty::codec::TyEncoder;
28 use rustc_middle::ty::fast_reject::{self, SimplifiedType, TreatParams};
29 use rustc_middle::ty::query::Providers;
30 use rustc_middle::ty::{self, SymbolName, Ty, TyCtxt};
31 use rustc_serialize::{opaque, Decodable, Decoder, Encodable, Encoder};
32 use rustc_session::config::CrateType;
33 use rustc_session::cstore::{ForeignModule, LinkagePreference, NativeLib};
34 use rustc_span::hygiene::{ExpnIndex, HygieneEncodeContext, MacroKind};
35 use rustc_span::symbol::{sym, Symbol};
37 self, DebuggerVisualizerFile, ExternalSource, FileName, SourceFile, Span, SyntaxContext,
39 use rustc_target::abi::VariantIdx;
40 use std::borrow::Borrow;
41 use std::collections::hash_map::Entry;
43 use std::io::{Read, Seek, Write};
45 use std::num::NonZeroUsize;
46 use std::path::{Path, PathBuf};
48 pub(super) struct EncodeContext<'a, 'tcx> {
49 opaque: opaque::FileEncoder,
51 feat: &'tcx rustc_feature::Features,
53 tables: TableBuilders,
55 lazy_state: LazyState,
56 type_shorthands: FxHashMap<Ty<'tcx>, usize>,
57 predicate_shorthands: FxHashMap<ty::PredicateKind<'tcx>, usize>,
59 interpret_allocs: FxIndexSet<interpret::AllocId>,
61 // This is used to speed up Span encoding.
62 // The `usize` is an index into the `MonotonicVec`
63 // that stores the `SourceFile`
64 source_file_cache: (Lrc<SourceFile>, usize),
65 // The indices (into the `SourceMap`'s `MonotonicVec`)
66 // of all of the `SourceFiles` that we need to serialize.
67 // When we serialize a `Span`, we insert the index of its
68 // `SourceFile` into the `FxIndexSet`.
69 // The order inside the `FxIndexSet` is used as on-disk
70 // order of `SourceFiles`, and encoded inside `Span`s.
71 required_source_files: Option<FxIndexSet<usize>>,
73 hygiene_ctxt: &'a HygieneEncodeContext,
74 symbol_table: FxHashMap<Symbol, usize>,
77 /// If the current crate is a proc-macro, returns early with `Lazy:empty()`.
78 /// This is useful for skipping the encoding of things that aren't needed
79 /// for proc-macro crates.
80 macro_rules! empty_proc_macro {
82 if $self.is_proc_macro {
83 return LazyArray::empty();
88 macro_rules! encoder_methods {
89 ($($name:ident($ty:ty);)*) => {
90 $(fn $name(&mut self, value: $ty) {
91 self.opaque.$name(value)
96 impl<'a, 'tcx> Encoder for EncodeContext<'a, 'tcx> {
117 emit_raw_bytes(&[u8]);
121 impl<'a, 'tcx, T> Encodable<EncodeContext<'a, 'tcx>> for LazyValue<T> {
122 fn encode(&self, e: &mut EncodeContext<'a, 'tcx>) {
123 e.emit_lazy_distance(self.position);
127 impl<'a, 'tcx, T> Encodable<EncodeContext<'a, 'tcx>> for LazyArray<T> {
128 fn encode(&self, e: &mut EncodeContext<'a, 'tcx>) {
129 e.emit_usize(self.num_elems);
130 if self.num_elems > 0 {
131 e.emit_lazy_distance(self.position)
136 impl<'a, 'tcx, I, T> Encodable<EncodeContext<'a, 'tcx>> for LazyTable<I, T> {
137 fn encode(&self, e: &mut EncodeContext<'a, 'tcx>) {
138 e.emit_usize(self.encoded_size);
139 e.emit_lazy_distance(self.position);
143 impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for CrateNum {
144 fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
145 if *self != LOCAL_CRATE && s.is_proc_macro {
146 panic!("Attempted to encode non-local CrateNum {:?} for proc-macro crate", self);
148 s.emit_u32(self.as_u32());
152 impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for DefIndex {
153 fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
154 s.emit_u32(self.as_u32());
158 impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for ExpnIndex {
159 fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
160 s.emit_u32(self.as_u32());
164 impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for SyntaxContext {
165 fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
166 rustc_span::hygiene::raw_encode_syntax_context(*self, &s.hygiene_ctxt, s);
170 impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for ExpnId {
171 fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
172 if self.krate == LOCAL_CRATE {
173 // We will only write details for local expansions. Non-local expansions will fetch
174 // data from the corresponding crate's metadata.
175 // FIXME(#43047) FIXME(#74731) We may eventually want to avoid relying on external
176 // metadata from proc-macro crates.
177 s.hygiene_ctxt.schedule_expn_data_for_encoding(*self);
179 self.krate.encode(s);
180 self.local_id.encode(s);
184 impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for Span {
185 fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
186 let span = self.data();
188 // Don't serialize any `SyntaxContext`s from a proc-macro crate,
189 // since we don't load proc-macro dependencies during serialization.
190 // This means that any hygiene information from macros used *within*
191 // a proc-macro crate (e.g. invoking a macro that expands to a proc-macro
192 // definition) will be lost.
194 // This can show up in two ways:
196 // 1. Any hygiene information associated with identifier of
197 // a proc macro (e.g. `#[proc_macro] pub fn $name`) will be lost.
198 // Since proc-macros can only be invoked from a different crate,
199 // real code should never need to care about this.
201 // 2. Using `Span::def_site` or `Span::mixed_site` will not
202 // include any hygiene information associated with the definition
203 // site. This means that a proc-macro cannot emit a `$crate`
204 // identifier which resolves to one of its dependencies,
205 // which also should never come up in practice.
207 // Additionally, this affects `Span::parent`, and any other
208 // span inspection APIs that would otherwise allow traversing
209 // the `SyntaxContexts` associated with a span.
211 // None of these user-visible effects should result in any
212 // cross-crate inconsistencies (getting one behavior in the same
213 // crate, and a different behavior in another crate) due to the
214 // limited surface that proc-macros can expose.
216 // IMPORTANT: If this is ever changed, be sure to update
217 // `rustc_span::hygiene::raw_encode_expn_id` to handle
218 // encoding `ExpnData` for proc-macro crates.
220 SyntaxContext::root().encode(s);
226 return TAG_PARTIAL_SPAN.encode(s);
229 // The Span infrastructure should make sure that this invariant holds:
230 debug_assert!(span.lo <= span.hi);
232 if !s.source_file_cache.0.contains(span.lo) {
233 let source_map = s.tcx.sess.source_map();
234 let source_file_index = source_map.lookup_source_file_idx(span.lo);
235 s.source_file_cache =
236 (source_map.files()[source_file_index].clone(), source_file_index);
238 let (ref source_file, source_file_index) = s.source_file_cache;
239 debug_assert!(source_file.contains(span.lo));
241 if !source_file.contains(span.hi) {
242 // Unfortunately, macro expansion still sometimes generates Spans
243 // that malformed in this way.
244 return TAG_PARTIAL_SPAN.encode(s);
247 // There are two possible cases here:
248 // 1. This span comes from a 'foreign' crate - e.g. some crate upstream of the
249 // crate we are writing metadata for. When the metadata for *this* crate gets
250 // deserialized, the deserializer will need to know which crate it originally came
251 // from. We use `TAG_VALID_SPAN_FOREIGN` to indicate that a `CrateNum` should
252 // be deserialized after the rest of the span data, which tells the deserializer
253 // which crate contains the source map information.
254 // 2. This span comes from our own crate. No special handling is needed - we just
255 // write `TAG_VALID_SPAN_LOCAL` to let the deserializer know that it should use
256 // our own source map information.
258 // If we're a proc-macro crate, we always treat this as a local `Span`.
259 // In `encode_source_map`, we serialize foreign `SourceFile`s into our metadata
260 // if we're a proc-macro crate.
261 // This allows us to avoid loading the dependencies of proc-macro crates: all of
262 // the information we need to decode `Span`s is stored in the proc-macro crate.
263 let (tag, metadata_index) = if source_file.is_imported() && !s.is_proc_macro {
264 // To simplify deserialization, we 'rebase' this span onto the crate it originally came from
265 // (the crate that 'owns' the file it references. These rebased 'lo' and 'hi' values
266 // are relative to the source map information for the 'foreign' crate whose CrateNum
267 // we write into the metadata. This allows `imported_source_files` to binary
268 // search through the 'foreign' crate's source map information, using the
269 // deserialized 'lo' and 'hi' values directly.
271 // All of this logic ensures that the final result of deserialization is a 'normal'
272 // Span that can be used without any additional trouble.
273 let metadata_index = {
274 // Introduce a new scope so that we drop the 'lock()' temporary
275 match &*source_file.external_src.lock() {
276 ExternalSource::Foreign { metadata_index, .. } => *metadata_index,
277 src => panic!("Unexpected external source {:?}", src),
281 (TAG_VALID_SPAN_FOREIGN, metadata_index)
283 // Record the fact that we need to encode the data for this `SourceFile`
285 s.required_source_files.as_mut().expect("Already encoded SourceMap!");
286 let (metadata_index, _) = source_files.insert_full(source_file_index);
287 let metadata_index: u32 =
288 metadata_index.try_into().expect("cannot export more than U32_MAX files");
290 (TAG_VALID_SPAN_LOCAL, metadata_index)
293 // Encode the start position relative to the file start, so we profit more from the
294 // variable-length integer encoding.
295 let lo = span.lo - source_file.start_pos;
297 // Encode length which is usually less than span.hi and profits more
298 // from the variable-length integer encoding that we use.
299 let len = span.hi - span.lo;
305 // Encode the index of the `SourceFile` for the span, in order to make decoding faster.
306 metadata_index.encode(s);
308 if tag == TAG_VALID_SPAN_FOREIGN {
309 // This needs to be two lines to avoid holding the `s.source_file_cache`
310 // while calling `cnum.encode(s)`
311 let cnum = s.source_file_cache.0.cnum;
317 impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for Symbol {
318 fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
319 // if symbol preinterned, emit tag and symbol index
320 if self.is_preinterned() {
321 s.opaque.emit_u8(SYMBOL_PREINTERNED);
322 s.opaque.emit_u32(self.as_u32());
324 // otherwise write it as string or as offset to it
325 match s.symbol_table.entry(*self) {
326 Entry::Vacant(o) => {
327 s.opaque.emit_u8(SYMBOL_STR);
328 let pos = s.opaque.position();
330 s.emit_str(self.as_str());
332 Entry::Occupied(o) => {
333 let x = o.get().clone();
334 s.emit_u8(SYMBOL_OFFSET);
342 impl<'a, 'tcx> TyEncoder for EncodeContext<'a, 'tcx> {
343 const CLEAR_CROSS_CRATE: bool = true;
345 type I = TyCtxt<'tcx>;
347 fn position(&self) -> usize {
348 self.opaque.position()
351 fn type_shorthands(&mut self) -> &mut FxHashMap<Ty<'tcx>, usize> {
352 &mut self.type_shorthands
355 fn predicate_shorthands(&mut self) -> &mut FxHashMap<ty::PredicateKind<'tcx>, usize> {
356 &mut self.predicate_shorthands
359 fn encode_alloc_id(&mut self, alloc_id: &rustc_middle::mir::interpret::AllocId) {
360 let (index, _) = self.interpret_allocs.insert_full(*alloc_id);
366 // Shorthand for `$self.$tables.$table.set($def_id.index, $self.lazy_value($value))`, which would
367 // normally need extra variables to avoid errors about multiple mutable borrows.
368 macro_rules! record {
369 ($self:ident.$tables:ident.$table:ident[$def_id:expr] <- $value:expr) => {{
372 let lazy = $self.lazy(value);
373 $self.$tables.$table.set($def_id.index, lazy);
378 // Shorthand for `$self.$tables.$table.set($def_id.index, $self.lazy_value($value))`, which would
379 // normally need extra variables to avoid errors about multiple mutable borrows.
380 macro_rules! record_array {
381 ($self:ident.$tables:ident.$table:ident[$def_id:expr] <- $value:expr) => {{
384 let lazy = $self.lazy_array(value);
385 $self.$tables.$table.set($def_id.index, lazy);
390 impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
391 fn emit_lazy_distance(&mut self, position: NonZeroUsize) {
392 let pos = position.get();
393 let distance = match self.lazy_state {
394 LazyState::NoNode => bug!("emit_lazy_distance: outside of a metadata node"),
395 LazyState::NodeStart(start) => {
396 let start = start.get();
397 assert!(pos <= start);
400 LazyState::Previous(last_pos) => {
402 last_pos <= position,
403 "make sure that the calls to `lazy*` \
404 are in the same order as the metadata fields",
406 position.get() - last_pos.get()
409 self.lazy_state = LazyState::Previous(NonZeroUsize::new(pos).unwrap());
410 self.emit_usize(distance);
413 fn lazy<T: ParameterizedOverTcx, B: Borrow<T::Value<'tcx>>>(&mut self, value: B) -> LazyValue<T>
415 T::Value<'tcx>: Encodable<EncodeContext<'a, 'tcx>>,
417 let pos = NonZeroUsize::new(self.position()).unwrap();
419 assert_eq!(self.lazy_state, LazyState::NoNode);
420 self.lazy_state = LazyState::NodeStart(pos);
421 value.borrow().encode(self);
422 self.lazy_state = LazyState::NoNode;
424 assert!(pos.get() <= self.position());
426 LazyValue::from_position(pos)
429 fn lazy_array<T: ParameterizedOverTcx, I: IntoIterator<Item = B>, B: Borrow<T::Value<'tcx>>>(
434 T::Value<'tcx>: Encodable<EncodeContext<'a, 'tcx>>,
436 let pos = NonZeroUsize::new(self.position()).unwrap();
438 assert_eq!(self.lazy_state, LazyState::NoNode);
439 self.lazy_state = LazyState::NodeStart(pos);
440 let len = values.into_iter().map(|value| value.borrow().encode(self)).count();
441 self.lazy_state = LazyState::NoNode;
443 assert!(pos.get() <= self.position());
445 LazyArray::from_position_and_num_elems(pos, len)
448 fn encode_info_for_items(&mut self) {
449 self.encode_info_for_mod(CRATE_DEF_ID, self.tcx.hir().root_module());
451 // Proc-macro crates only export proc-macro items, which are looked
452 // up using `proc_macro_data`
453 if self.is_proc_macro {
457 self.tcx.hir().visit_all_item_likes_in_crate(self);
460 fn encode_def_path_table(&mut self) {
461 let table = self.tcx.def_path_table();
462 if self.is_proc_macro {
463 for def_index in std::iter::once(CRATE_DEF_INDEX)
464 .chain(self.tcx.resolutions(()).proc_macros.iter().map(|p| p.local_def_index))
466 let def_key = self.lazy(table.def_key(def_index));
467 let def_path_hash = table.def_path_hash(def_index);
468 self.tables.def_keys.set(def_index, def_key);
469 self.tables.def_path_hashes.set(def_index, def_path_hash);
472 for (def_index, def_key, def_path_hash) in table.enumerated_keys_and_path_hashes() {
473 let def_key = self.lazy(def_key);
474 self.tables.def_keys.set(def_index, def_key);
475 self.tables.def_path_hashes.set(def_index, *def_path_hash);
480 fn encode_def_path_hash_map(&mut self) -> LazyValue<DefPathHashMapRef<'static>> {
481 self.lazy(DefPathHashMapRef::BorrowedFromTcx(self.tcx.def_path_hash_to_def_index_map()))
484 fn encode_source_map(&mut self) -> LazyTable<u32, LazyValue<rustc_span::SourceFile>> {
485 let source_map = self.tcx.sess.source_map();
486 let all_source_files = source_map.files();
488 // By replacing the `Option` with `None`, we ensure that we can't
489 // accidentally serialize any more `Span`s after the source map encoding
491 let required_source_files = self.required_source_files.take().unwrap();
493 let working_directory = &self.tcx.sess.opts.working_dir;
495 let mut adapted = TableBuilder::default();
497 // Only serialize `SourceFile`s that were used during the encoding of a `Span`.
499 // The order in which we encode source files is important here: the on-disk format for
500 // `Span` contains the index of the corresponding `SourceFile`.
501 for (on_disk_index, &source_file_index) in required_source_files.iter().enumerate() {
502 let source_file = &all_source_files[source_file_index];
503 // Don't serialize imported `SourceFile`s, unless we're in a proc-macro crate.
504 assert!(!source_file.is_imported() || self.is_proc_macro);
506 // At export time we expand all source file paths to absolute paths because
507 // downstream compilation sessions can have a different compiler working
508 // directory, so relative paths from this or any other upstream crate
509 // won't be valid anymore.
511 // At this point we also erase the actual on-disk path and only keep
512 // the remapped version -- as is necessary for reproducible builds.
513 let mut source_file = match source_file.name {
514 FileName::Real(ref original_file_name) => {
515 let adapted_file_name = source_map
517 .to_embeddable_absolute_path(original_file_name.clone(), working_directory);
519 if adapted_file_name != *original_file_name {
520 let mut adapted: SourceFile = (**source_file).clone();
521 adapted.name = FileName::Real(adapted_file_name);
522 adapted.name_hash = {
523 let mut hasher: StableHasher = StableHasher::new();
524 adapted.name.hash(&mut hasher);
525 hasher.finish::<u128>()
533 // expanded code, not from a file
534 _ => source_file.clone(),
537 // We're serializing this `SourceFile` into our crate metadata,
538 // so mark it as coming from this crate.
539 // This also ensures that we don't try to deserialize the
540 // `CrateNum` for a proc-macro dependency - since proc macro
541 // dependencies aren't loaded when we deserialize a proc-macro,
542 // trying to remap the `CrateNum` would fail.
543 if self.is_proc_macro {
544 Lrc::make_mut(&mut source_file).cnum = LOCAL_CRATE;
547 let on_disk_index: u32 =
548 on_disk_index.try_into().expect("cannot export more than U32_MAX files");
549 adapted.set(on_disk_index, self.lazy(source_file));
552 adapted.encode(&mut self.opaque)
555 fn encode_crate_root(&mut self) -> LazyValue<CrateRoot> {
558 let preamble_bytes = self.position() - i;
560 // Encode the crate deps
562 let crate_deps = self.encode_crate_deps();
563 let dylib_dependency_formats = self.encode_dylib_dependency_formats();
564 let dep_bytes = self.position() - i;
566 // Encode the lib features.
568 let lib_features = self.encode_lib_features();
569 let lib_feature_bytes = self.position() - i;
571 // Encode the stability implications.
573 let stability_implications = self.encode_stability_implications();
574 let stability_implications_bytes = self.position() - i;
576 // Encode the language items.
578 let lang_items = self.encode_lang_items();
579 let lang_items_missing = self.encode_lang_items_missing();
580 let lang_item_bytes = self.position() - i;
582 // Encode the diagnostic items.
584 let diagnostic_items = self.encode_diagnostic_items();
585 let diagnostic_item_bytes = self.position() - i;
587 // Encode the native libraries used
589 let native_libraries = self.encode_native_libraries();
590 let native_lib_bytes = self.position() - i;
593 let foreign_modules = self.encode_foreign_modules();
594 let foreign_modules_bytes = self.position() - i;
596 // Encode DefPathTable
598 self.encode_def_path_table();
599 let def_path_table_bytes = self.position() - i;
601 // Encode the def IDs of traits, for rustdoc and diagnostics.
603 let traits = self.encode_traits();
604 let traits_bytes = self.position() - i;
606 // Encode the def IDs of impls, for coherence checking.
608 let impls = self.encode_impls();
609 let impls_bytes = self.position() - i;
612 let incoherent_impls = self.encode_incoherent_impls();
613 let incoherent_impls_bytes = self.position() - i;
618 let mir_bytes = self.position() - i;
622 self.encode_def_ids();
623 self.encode_info_for_items();
624 let item_bytes = self.position() - i;
626 // Encode the allocation index
628 let interpret_alloc_index = {
629 let mut interpret_alloc_index = Vec::new();
631 trace!("beginning to encode alloc ids");
633 let new_n = self.interpret_allocs.len();
634 // if we have found new ids, serialize those, too
639 trace!("encoding {} further alloc ids", new_n - n);
640 for idx in n..new_n {
641 let id = self.interpret_allocs[idx];
642 let pos = self.position() as u32;
643 interpret_alloc_index.push(pos);
644 interpret::specialized_encode_alloc_id(self, tcx, id);
648 self.lazy_array(interpret_alloc_index)
650 let interpret_alloc_index_bytes = self.position() - i;
652 // Encode the proc macro data. This affects 'tables',
653 // so we need to do this before we encode the tables.
654 // This overwrites def_keys, so it must happen after encode_def_path_table.
656 let proc_macro_data = self.encode_proc_macros();
657 let proc_macro_data_bytes = self.position() - i;
660 let tables = self.tables.encode(&mut self.opaque);
661 let tables_bytes = self.position() - i;
664 let debugger_visualizers = self.encode_debugger_visualizers();
665 let debugger_visualizers_bytes = self.position() - i;
667 // Encode exported symbols info. This is prefetched in `encode_metadata` so we encode
668 // this as late as possible to give the prefetching as much time as possible to complete.
670 let exported_symbols = tcx.exported_symbols(LOCAL_CRATE);
671 let exported_symbols = self.encode_exported_symbols(&exported_symbols);
672 let exported_symbols_bytes = self.position() - i;
674 // Encode the hygiene data,
675 // IMPORTANT: this *must* be the last thing that we encode (other than `SourceMap`). The process
676 // of encoding other items (e.g. `optimized_mir`) may cause us to load
677 // data from the incremental cache. If this causes us to deserialize a `Span`,
678 // then we may load additional `SyntaxContext`s into the global `HygieneData`.
679 // Therefore, we need to encode the hygiene data last to ensure that we encode
680 // any `SyntaxContext`s that might be used.
682 let (syntax_contexts, expn_data, expn_hashes) = self.encode_hygiene();
683 let hygiene_bytes = self.position() - i;
686 let def_path_hash_map = self.encode_def_path_hash_map();
687 let def_path_hash_map_bytes = self.position() - i;
689 // Encode source_map. This needs to be done last,
690 // since encoding `Span`s tells us which `SourceFiles` we actually
693 let source_map = self.encode_source_map();
694 let source_map_bytes = self.position() - i;
697 let attrs = tcx.hir().krate_attrs();
698 let has_default_lib_allocator = tcx.sess.contains_name(&attrs, sym::default_lib_allocator);
699 let root = self.lazy(CrateRoot {
700 name: tcx.crate_name(LOCAL_CRATE),
701 extra_filename: tcx.sess.opts.cg.extra_filename.clone(),
702 triple: tcx.sess.opts.target_triple.clone(),
703 hash: tcx.crate_hash(LOCAL_CRATE),
704 stable_crate_id: tcx.def_path_hash(LOCAL_CRATE.as_def_id()).stable_crate_id(),
705 required_panic_strategy: tcx.required_panic_strategy(LOCAL_CRATE),
706 panic_in_drop_strategy: tcx.sess.opts.unstable_opts.panic_in_drop,
707 edition: tcx.sess.edition(),
708 has_global_allocator: tcx.has_global_allocator(LOCAL_CRATE),
709 has_panic_handler: tcx.has_panic_handler(LOCAL_CRATE),
710 has_default_lib_allocator,
712 debugger_visualizers,
713 compiler_builtins: tcx.sess.contains_name(&attrs, sym::compiler_builtins),
714 needs_allocator: tcx.sess.contains_name(&attrs, sym::needs_allocator),
715 needs_panic_runtime: tcx.sess.contains_name(&attrs, sym::needs_panic_runtime),
716 no_builtins: tcx.sess.contains_name(&attrs, sym::no_builtins),
717 panic_runtime: tcx.sess.contains_name(&attrs, sym::panic_runtime),
718 profiler_runtime: tcx.sess.contains_name(&attrs, sym::profiler_runtime),
719 symbol_mangling_version: tcx.sess.opts.get_symbol_mangling_version(),
722 dylib_dependency_formats,
724 stability_implications,
735 interpret_alloc_index,
742 let final_bytes = self.position() - i;
744 let total_bytes = self.position();
746 let computed_total_bytes = preamble_bytes
749 + stability_implications_bytes
751 + diagnostic_item_bytes
753 + foreign_modules_bytes
754 + def_path_table_bytes
757 + incoherent_impls_bytes
760 + interpret_alloc_index_bytes
761 + proc_macro_data_bytes
763 + debugger_visualizers_bytes
764 + exported_symbols_bytes
766 + def_path_hash_map_bytes
769 assert_eq!(total_bytes, computed_total_bytes);
771 if tcx.sess.meta_stats() {
774 // Rewind and re-read all the metadata to count the zero bytes we wrote.
775 let pos_before_rewind = self.opaque.file().stream_position().unwrap();
776 let mut zero_bytes = 0;
777 self.opaque.file().rewind().unwrap();
778 let file = std::io::BufReader::new(self.opaque.file());
779 for e in file.bytes() {
784 assert_eq!(self.opaque.file().stream_position().unwrap(), pos_before_rewind);
786 let perc = |bytes| (bytes * 100) as f64 / total_bytes as f64;
787 let p = |label, bytes| {
788 eprintln!("{:>21}: {:>8} bytes ({:4.1}%)", label, bytes, perc(bytes));
793 "{} metadata bytes, of which {} bytes ({:.1}%) are zero",
798 p("preamble", preamble_bytes);
800 p("lib feature", lib_feature_bytes);
801 p("stability_implications", stability_implications_bytes);
802 p("lang item", lang_item_bytes);
803 p("diagnostic item", diagnostic_item_bytes);
804 p("native lib", native_lib_bytes);
805 p("foreign modules", foreign_modules_bytes);
806 p("def-path table", def_path_table_bytes);
807 p("traits", traits_bytes);
808 p("impls", impls_bytes);
809 p("incoherent_impls", incoherent_impls_bytes);
811 p("item", item_bytes);
812 p("interpret_alloc_index", interpret_alloc_index_bytes);
813 p("proc-macro-data", proc_macro_data_bytes);
814 p("tables", tables_bytes);
815 p("debugger visualizers", debugger_visualizers_bytes);
816 p("exported symbols", exported_symbols_bytes);
817 p("hygiene", hygiene_bytes);
818 p("def-path hashes", def_path_hash_map_bytes);
819 p("source_map", source_map_bytes);
820 p("final", final_bytes);
828 fn should_encode_visibility(def_kind: DefKind) -> bool {
838 | DefKind::TraitAlias
842 | DefKind::Static(..)
845 | DefKind::AssocConst
848 | DefKind::ForeignMod
851 | DefKind::Field => true,
853 | DefKind::ConstParam
854 | DefKind::LifetimeParam
856 | DefKind::InlineConst
860 | DefKind::ExternCrate => false,
864 fn should_encode_stability(def_kind: DefKind) -> bool {
873 | DefKind::AssocConst
875 | DefKind::ConstParam
876 | DefKind::Static(..)
879 | DefKind::ForeignMod
886 | DefKind::TraitAlias
888 | DefKind::ForeignTy => true,
890 | DefKind::LifetimeParam
892 | DefKind::InlineConst
896 | DefKind::ExternCrate => false,
900 /// Whether we should encode MIR.
902 /// Computing, optimizing and encoding the MIR is a relatively expensive operation.
903 /// We want to avoid this work when not required. Therefore:
904 /// - we only compute `mir_for_ctfe` on items with const-eval semantics;
905 /// - we skip `optimized_mir` for check runs.
907 /// Return a pair, resp. for CTFE and for LLVM.
908 fn should_encode_mir(tcx: TyCtxt<'_>, def_id: LocalDefId) -> (bool, bool) {
909 match tcx.def_kind(def_id) {
911 DefKind::Ctor(_, _) => {
912 let mir_opt_base = tcx.sess.opts.output_types.should_codegen()
913 || tcx.sess.opts.unstable_opts.always_encode_mir;
918 | DefKind::InlineConst
919 | DefKind::AssocConst
920 | DefKind::Static(..)
921 | DefKind::Const => (true, false),
922 // Full-fledged functions
923 DefKind::AssocFn | DefKind::Fn => {
924 let generics = tcx.generics_of(def_id);
925 let needs_inline = (generics.requires_monomorphization(tcx)
926 || tcx.codegen_fn_attrs(def_id).requests_inline())
927 && tcx.sess.opts.output_types.should_codegen();
928 // The function has a `const` modifier or is in a `#[const_trait]`.
929 let is_const_fn = tcx.is_const_fn_raw(def_id.to_def_id())
930 || tcx.is_const_default_method(def_id.to_def_id());
931 let always_encode_mir = tcx.sess.opts.unstable_opts.always_encode_mir;
932 (is_const_fn, needs_inline || always_encode_mir)
934 // Closures can't be const fn.
935 DefKind::Closure => {
936 let generics = tcx.generics_of(def_id);
937 let needs_inline = (generics.requires_monomorphization(tcx)
938 || tcx.codegen_fn_attrs(def_id).requests_inline())
939 && tcx.sess.opts.output_types.should_codegen();
940 let always_encode_mir = tcx.sess.opts.unstable_opts.always_encode_mir;
941 (false, needs_inline || always_encode_mir)
943 // Generators require optimized MIR to compute layout.
944 DefKind::Generator => (false, true),
945 // The others don't have MIR.
950 fn should_encode_variances(def_kind: DefKind) -> bool {
958 | DefKind::AssocFn => true,
962 | DefKind::AssocConst
964 | DefKind::ConstParam
965 | DefKind::Static(..)
967 | DefKind::ForeignMod
972 | DefKind::TraitAlias
976 | DefKind::LifetimeParam
978 | DefKind::InlineConst
982 | DefKind::ExternCrate => false,
986 fn should_encode_generics(def_kind: DefKind) -> bool {
995 | DefKind::TraitAlias
999 | DefKind::Static(..)
1002 | DefKind::AssocConst
1003 | DefKind::AnonConst
1004 | DefKind::InlineConst
1010 | DefKind::Generator => true,
1012 | DefKind::ForeignMod
1013 | DefKind::ConstParam
1014 | DefKind::Macro(..)
1016 | DefKind::LifetimeParam
1017 | DefKind::GlobalAsm
1018 | DefKind::ExternCrate => false,
1022 fn should_encode_type(tcx: TyCtxt<'_>, def_id: LocalDefId, def_kind: DefKind) -> bool {
1032 | DefKind::Static(..)
1035 | DefKind::ForeignTy
1038 | DefKind::AssocConst
1040 | DefKind::Generator
1041 | DefKind::ConstParam
1042 | DefKind::AnonConst
1043 | DefKind::InlineConst => true,
1045 DefKind::AssocTy => {
1046 let assoc_item = tcx.associated_item(def_id);
1047 match assoc_item.container {
1048 ty::AssocItemContainer::ImplContainer => true,
1049 ty::AssocItemContainer::TraitContainer => assoc_item.defaultness(tcx).has_value(),
1052 DefKind::TyParam => {
1053 let hir::Node::GenericParam(param) = tcx.hir().get_by_def_id(def_id) else { bug!() };
1054 let hir::GenericParamKind::Type { default, .. } = param.kind else { bug!() };
1059 | DefKind::TraitAlias
1061 | DefKind::ForeignMod
1062 | DefKind::Macro(..)
1064 | DefKind::LifetimeParam
1065 | DefKind::GlobalAsm
1066 | DefKind::ExternCrate => false,
1070 fn should_encode_const(def_kind: DefKind) -> bool {
1072 DefKind::Const | DefKind::AssocConst | DefKind::AnonConst => true,
1081 | DefKind::Static(..)
1084 | DefKind::ForeignTy
1088 | DefKind::Generator
1089 | DefKind::ConstParam
1090 | DefKind::InlineConst
1094 | DefKind::TraitAlias
1096 | DefKind::ForeignMod
1097 | DefKind::Macro(..)
1099 | DefKind::LifetimeParam
1100 | DefKind::GlobalAsm
1101 | DefKind::ExternCrate => false,
1105 impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
1106 fn encode_attrs(&mut self, def_id: LocalDefId) {
1107 let mut attrs = self
1110 .attrs(self.tcx.hir().local_def_id_to_hir_id(def_id))
1112 .filter(|attr| !rustc_feature::is_builtin_only_local(attr.name_or_empty()));
1114 record_array!(self.tables.attributes[def_id.to_def_id()] <- attrs.clone());
1115 if attrs.any(|attr| attr.may_have_doc_links()) {
1116 self.tables.may_have_doc_links.set(def_id.local_def_index, ());
1120 fn encode_def_ids(&mut self) {
1121 if self.is_proc_macro {
1125 for local_id in tcx.iter_local_def_id() {
1126 let def_id = local_id.to_def_id();
1127 let def_kind = tcx.opt_def_kind(local_id);
1128 let Some(def_kind) = def_kind else { continue };
1129 self.tables.opt_def_kind.set(def_id.index, def_kind);
1130 let def_span = tcx.def_span(local_id);
1131 record!(self.tables.def_span[def_id] <- def_span);
1132 self.encode_attrs(local_id);
1133 record!(self.tables.expn_that_defined[def_id] <- self.tcx.expn_that_defined(def_id));
1134 if let Some(ident_span) = tcx.def_ident_span(def_id) {
1135 record!(self.tables.def_ident_span[def_id] <- ident_span);
1137 if def_kind.has_codegen_attrs() {
1138 record!(self.tables.codegen_fn_attrs[def_id] <- self.tcx.codegen_fn_attrs(def_id));
1140 if should_encode_visibility(def_kind) {
1141 record!(self.tables.visibility[def_id] <- self.tcx.visibility(def_id));
1143 if should_encode_stability(def_kind) {
1144 self.encode_stability(def_id);
1145 self.encode_const_stability(def_id);
1146 self.encode_default_body_stability(def_id);
1147 self.encode_deprecation(def_id);
1149 if should_encode_variances(def_kind) {
1150 let v = self.tcx.variances_of(def_id);
1151 record_array!(self.tables.variances_of[def_id] <- v);
1153 if should_encode_generics(def_kind) {
1154 let g = tcx.generics_of(def_id);
1155 record!(self.tables.generics_of[def_id] <- g);
1156 record!(self.tables.explicit_predicates_of[def_id] <- self.tcx.explicit_predicates_of(def_id));
1157 let inferred_outlives = self.tcx.inferred_outlives_of(def_id);
1158 if !inferred_outlives.is_empty() {
1159 record_array!(self.tables.inferred_outlives_of[def_id] <- inferred_outlives);
1162 if should_encode_type(tcx, local_id, def_kind) {
1163 record!(self.tables.type_of[def_id] <- self.tcx.type_of(def_id));
1165 if let DefKind::TyParam = def_kind {
1166 let default = self.tcx.object_lifetime_default(def_id);
1167 record!(self.tables.object_lifetime_default[def_id] <- default);
1169 if let DefKind::Trait | DefKind::TraitAlias = def_kind {
1170 record!(self.tables.super_predicates_of[def_id] <- self.tcx.super_predicates_of(def_id));
1173 let inherent_impls = tcx.crate_inherent_impls(());
1174 for (def_id, implementations) in inherent_impls.inherent_impls.iter() {
1175 if implementations.is_empty() {
1178 record_array!(self.tables.inherent_impls[def_id.to_def_id()] <- implementations.iter().map(|&def_id| {
1179 assert!(def_id.is_local());
1185 fn encode_enum_variant_info(&mut self, def: ty::AdtDef<'tcx>, index: VariantIdx) {
1187 let variant = &def.variant(index);
1188 let def_id = variant.def_id;
1189 debug!("EncodeContext::encode_enum_variant_info({:?})", def_id);
1191 let data = VariantData {
1192 ctor_kind: variant.ctor_kind,
1193 discr: variant.discr,
1194 ctor: variant.ctor_def_id.map(|did| did.index),
1195 is_non_exhaustive: variant.is_field_list_non_exhaustive(),
1198 record!(self.tables.variant_data[def_id] <- data);
1199 self.tables.constness.set(def_id.index, hir::Constness::Const);
1200 record_array!(self.tables.children[def_id] <- variant.fields.iter().map(|f| {
1201 assert!(f.did.is_local());
1204 if variant.ctor_kind == CtorKind::Fn {
1205 // FIXME(eddyb) encode signature only in `encode_enum_variant_ctor`.
1206 if let Some(ctor_def_id) = variant.ctor_def_id {
1207 record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(ctor_def_id));
1212 fn encode_enum_variant_ctor(&mut self, def: ty::AdtDef<'tcx>, index: VariantIdx) {
1214 let variant = &def.variant(index);
1215 let def_id = variant.ctor_def_id.unwrap();
1216 debug!("EncodeContext::encode_enum_variant_ctor({:?})", def_id);
1218 // FIXME(eddyb) encode only the `CtorKind` for constructors.
1219 let data = VariantData {
1220 ctor_kind: variant.ctor_kind,
1221 discr: variant.discr,
1222 ctor: Some(def_id.index),
1223 is_non_exhaustive: variant.is_field_list_non_exhaustive(),
1226 record!(self.tables.variant_data[def_id] <- data);
1227 self.tables.constness.set(def_id.index, hir::Constness::Const);
1228 if variant.ctor_kind == CtorKind::Fn {
1229 record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
1233 fn encode_info_for_mod(&mut self, local_def_id: LocalDefId, md: &hir::Mod<'_>) {
1235 let def_id = local_def_id.to_def_id();
1236 debug!("EncodeContext::encode_info_for_mod({:?})", def_id);
1238 // If we are encoding a proc-macro crates, `encode_info_for_mod` will
1239 // only ever get called for the crate root. We still want to encode
1240 // the crate root for consistency with other crates (some of the resolver
1241 // code uses it). However, we skip encoding anything relating to child
1242 // items - we encode information about proc-macros later on.
1243 let reexports = if !self.is_proc_macro {
1244 tcx.module_reexports(local_def_id).unwrap_or(&[])
1249 record_array!(self.tables.module_reexports[def_id] <- reexports);
1250 if self.is_proc_macro {
1251 // Encode this here because we don't do it in encode_def_ids.
1252 record!(self.tables.expn_that_defined[def_id] <- tcx.expn_that_defined(local_def_id));
1254 record_array!(self.tables.children[def_id] <- iter::from_generator(|| {
1255 for item_id in md.item_ids {
1256 match tcx.hir().item(*item_id).kind {
1257 // Foreign items are planted into their parent modules
1258 // from name resolution point of view.
1259 hir::ItemKind::ForeignMod { items, .. } => {
1260 for foreign_item in items {
1261 yield foreign_item.id.def_id.local_def_index;
1264 // Only encode named non-reexport children, reexports are encoded
1265 // separately and unnamed items are not used by name resolution.
1266 hir::ItemKind::ExternCrate(..) => continue,
1267 _ if tcx.def_key(item_id.def_id.to_def_id()).get_opt_name().is_some() => {
1268 yield item_id.def_id.local_def_index;
1277 fn encode_struct_ctor(&mut self, adt_def: ty::AdtDef<'tcx>, def_id: DefId) {
1278 debug!("EncodeContext::encode_struct_ctor({:?})", def_id);
1280 let variant = adt_def.non_enum_variant();
1282 let data = VariantData {
1283 ctor_kind: variant.ctor_kind,
1284 discr: variant.discr,
1285 ctor: Some(def_id.index),
1286 is_non_exhaustive: variant.is_field_list_non_exhaustive(),
1289 record!(self.tables.repr_options[def_id] <- adt_def.repr());
1290 record!(self.tables.variant_data[def_id] <- data);
1291 self.tables.constness.set(def_id.index, hir::Constness::Const);
1292 if variant.ctor_kind == CtorKind::Fn {
1293 record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
1297 fn encode_explicit_item_bounds(&mut self, def_id: DefId) {
1298 debug!("EncodeContext::encode_explicit_item_bounds({:?})", def_id);
1299 let bounds = self.tcx.explicit_item_bounds(def_id);
1300 if !bounds.is_empty() {
1301 record_array!(self.tables.explicit_item_bounds[def_id] <- bounds);
1305 fn encode_info_for_trait_item(&mut self, def_id: DefId) {
1306 debug!("EncodeContext::encode_info_for_trait_item({:?})", def_id);
1309 let ast_item = tcx.hir().expect_trait_item(def_id.expect_local());
1310 self.tables.impl_defaultness.set(def_id.index, ast_item.defaultness);
1311 let trait_item = tcx.associated_item(def_id);
1312 self.tables.assoc_container.set(def_id.index, trait_item.container);
1314 match trait_item.kind {
1315 ty::AssocKind::Const => {}
1316 ty::AssocKind::Fn => {
1317 let hir::TraitItemKind::Fn(m_sig, m) = &ast_item.kind else { bug!() };
1319 hir::TraitFn::Required(ref names) => {
1320 record_array!(self.tables.fn_arg_names[def_id] <- *names)
1322 hir::TraitFn::Provided(body) => {
1323 record_array!(self.tables.fn_arg_names[def_id] <- self.tcx.hir().body_param_names(body))
1326 self.tables.asyncness.set(def_id.index, m_sig.header.asyncness);
1327 self.tables.constness.set(def_id.index, hir::Constness::NotConst);
1329 ty::AssocKind::Type => {
1330 self.encode_explicit_item_bounds(def_id);
1333 if trait_item.kind == ty::AssocKind::Fn {
1334 record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
1338 fn encode_info_for_impl_item(&mut self, def_id: DefId) {
1339 debug!("EncodeContext::encode_info_for_impl_item({:?})", def_id);
1342 let ast_item = self.tcx.hir().expect_impl_item(def_id.expect_local());
1343 self.tables.impl_defaultness.set(def_id.index, ast_item.defaultness);
1344 let impl_item = self.tcx.associated_item(def_id);
1345 self.tables.assoc_container.set(def_id.index, impl_item.container);
1347 match impl_item.kind {
1348 ty::AssocKind::Fn => {
1349 let hir::ImplItemKind::Fn(ref sig, body) = ast_item.kind else { bug!() };
1350 self.tables.asyncness.set(def_id.index, sig.header.asyncness);
1351 record_array!(self.tables.fn_arg_names[def_id] <- self.tcx.hir().body_param_names(body));
1352 // Can be inside `impl const Trait`, so using sig.header.constness is not reliable
1353 let constness = if self.tcx.is_const_fn_raw(def_id) {
1354 hir::Constness::Const
1356 hir::Constness::NotConst
1358 self.tables.constness.set(def_id.index, constness);
1360 ty::AssocKind::Const | ty::AssocKind::Type => {}
1362 if let Some(trait_item_def_id) = impl_item.trait_item_def_id {
1363 self.tables.trait_item_def_id.set(def_id.index, trait_item_def_id.into());
1365 if impl_item.kind == ty::AssocKind::Fn {
1366 record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
1367 if tcx.is_intrinsic(def_id) {
1368 self.tables.is_intrinsic.set(def_id.index, ());
1373 fn encode_mir(&mut self) {
1374 if self.is_proc_macro {
1380 let keys_and_jobs = tcx.mir_keys(()).iter().filter_map(|&def_id| {
1381 let (encode_const, encode_opt) = should_encode_mir(tcx, def_id);
1382 if encode_const || encode_opt { Some((def_id, encode_const, encode_opt)) } else { None }
1384 for (def_id, encode_const, encode_opt) in keys_and_jobs {
1385 debug_assert!(encode_const || encode_opt);
1387 debug!("EntryBuilder::encode_mir({:?})", def_id);
1389 record!(self.tables.optimized_mir[def_id.to_def_id()] <- tcx.optimized_mir(def_id));
1392 record!(self.tables.mir_for_ctfe[def_id.to_def_id()] <- tcx.mir_for_ctfe(def_id));
1394 // FIXME(generic_const_exprs): this feels wrong to have in `encode_mir`
1395 let abstract_const = tcx.thir_abstract_const(def_id);
1396 if let Ok(Some(abstract_const)) = abstract_const {
1397 record!(self.tables.thir_abstract_const[def_id.to_def_id()] <- abstract_const);
1400 if should_encode_const(tcx.def_kind(def_id)) {
1401 let qualifs = tcx.mir_const_qualif(def_id);
1402 record!(self.tables.mir_const_qualif[def_id.to_def_id()] <- qualifs);
1403 let body_id = tcx.hir().maybe_body_owned_by(def_id);
1404 if let Some(body_id) = body_id {
1405 let const_data = self.encode_rendered_const_for_body(body_id);
1406 record!(self.tables.rendered_const[def_id.to_def_id()] <- const_data);
1410 record!(self.tables.promoted_mir[def_id.to_def_id()] <- tcx.promoted_mir(def_id));
1413 ty::InstanceDef::Item(ty::WithOptConstParam::unknown(def_id.to_def_id()));
1414 let unused = tcx.unused_generic_params(instance);
1415 if !unused.is_empty() {
1416 record!(self.tables.unused_generic_params[def_id.to_def_id()] <- unused);
1421 fn encode_stability(&mut self, def_id: DefId) {
1422 debug!("EncodeContext::encode_stability({:?})", def_id);
1424 // The query lookup can take a measurable amount of time in crates with many items. Check if
1425 // the stability attributes are even enabled before using their queries.
1426 if self.feat.staged_api || self.tcx.sess.opts.unstable_opts.force_unstable_if_unmarked {
1427 if let Some(stab) = self.tcx.lookup_stability(def_id) {
1428 record!(self.tables.lookup_stability[def_id] <- stab)
1433 fn encode_const_stability(&mut self, def_id: DefId) {
1434 debug!("EncodeContext::encode_const_stability({:?})", def_id);
1436 // The query lookup can take a measurable amount of time in crates with many items. Check if
1437 // the stability attributes are even enabled before using their queries.
1438 if self.feat.staged_api || self.tcx.sess.opts.unstable_opts.force_unstable_if_unmarked {
1439 if let Some(stab) = self.tcx.lookup_const_stability(def_id) {
1440 record!(self.tables.lookup_const_stability[def_id] <- stab)
1445 fn encode_default_body_stability(&mut self, def_id: DefId) {
1446 debug!("EncodeContext::encode_default_body_stability({:?})", def_id);
1448 // The query lookup can take a measurable amount of time in crates with many items. Check if
1449 // the stability attributes are even enabled before using their queries.
1450 if self.feat.staged_api || self.tcx.sess.opts.unstable_opts.force_unstable_if_unmarked {
1451 if let Some(stab) = self.tcx.lookup_default_body_stability(def_id) {
1452 record!(self.tables.lookup_default_body_stability[def_id] <- stab)
1457 fn encode_deprecation(&mut self, def_id: DefId) {
1458 debug!("EncodeContext::encode_deprecation({:?})", def_id);
1459 if let Some(depr) = self.tcx.lookup_deprecation(def_id) {
1460 record!(self.tables.lookup_deprecation_entry[def_id] <- depr);
1464 fn encode_rendered_const_for_body(&mut self, body_id: hir::BodyId) -> String {
1465 let hir = self.tcx.hir();
1466 let body = hir.body(body_id);
1467 rustc_hir_pretty::to_string(&(&hir as &dyn intravisit::Map<'_>), |s| {
1468 s.print_expr(&body.value)
1472 fn encode_info_for_item(&mut self, def_id: DefId, item: &'tcx hir::Item<'tcx>) {
1475 debug!("EncodeContext::encode_info_for_item({:?})", def_id);
1478 hir::ItemKind::Fn(ref sig, .., body) => {
1479 self.tables.asyncness.set(def_id.index, sig.header.asyncness);
1480 record_array!(self.tables.fn_arg_names[def_id] <- self.tcx.hir().body_param_names(body));
1481 self.tables.constness.set(def_id.index, sig.header.constness);
1483 hir::ItemKind::Macro(ref macro_def, _) => {
1484 if macro_def.macro_rules {
1485 self.tables.macro_rules.set(def_id.index, ());
1487 record!(self.tables.macro_definition[def_id] <- &*macro_def.body);
1489 hir::ItemKind::Mod(ref m) => {
1490 return self.encode_info_for_mod(item.def_id, m);
1492 hir::ItemKind::OpaqueTy(..) => {
1493 self.encode_explicit_item_bounds(def_id);
1495 hir::ItemKind::Enum(..) => {
1496 let adt_def = self.tcx.adt_def(def_id);
1497 record!(self.tables.repr_options[def_id] <- adt_def.repr());
1499 hir::ItemKind::Struct(ref struct_def, _) => {
1500 let adt_def = self.tcx.adt_def(def_id);
1501 record!(self.tables.repr_options[def_id] <- adt_def.repr());
1502 self.tables.constness.set(def_id.index, hir::Constness::Const);
1504 // Encode def_ids for each field and method
1505 // for methods, write all the stuff get_trait_method
1507 let ctor = struct_def
1509 .map(|ctor_hir_id| self.tcx.hir().local_def_id(ctor_hir_id).local_def_index);
1511 let variant = adt_def.non_enum_variant();
1512 record!(self.tables.variant_data[def_id] <- VariantData {
1513 ctor_kind: variant.ctor_kind,
1514 discr: variant.discr,
1516 is_non_exhaustive: variant.is_field_list_non_exhaustive(),
1519 hir::ItemKind::Union(..) => {
1520 let adt_def = self.tcx.adt_def(def_id);
1521 record!(self.tables.repr_options[def_id] <- adt_def.repr());
1523 let variant = adt_def.non_enum_variant();
1524 record!(self.tables.variant_data[def_id] <- VariantData {
1525 ctor_kind: variant.ctor_kind,
1526 discr: variant.discr,
1528 is_non_exhaustive: variant.is_field_list_non_exhaustive(),
1531 hir::ItemKind::Impl(hir::Impl { defaultness, constness, .. }) => {
1532 self.tables.impl_defaultness.set(def_id.index, *defaultness);
1533 self.tables.constness.set(def_id.index, *constness);
1535 let trait_ref = self.tcx.impl_trait_ref(def_id);
1536 if let Some(trait_ref) = trait_ref {
1537 let trait_def = self.tcx.trait_def(trait_ref.def_id);
1538 if let Some(mut an) = trait_def.ancestors(self.tcx, def_id).ok() {
1539 if let Some(specialization_graph::Node::Impl(parent)) = an.nth(1) {
1540 self.tables.impl_parent.set(def_id.index, parent.into());
1544 // if this is an impl of `CoerceUnsized`, create its
1545 // "unsized info", else just store None
1546 if Some(trait_ref.def_id) == self.tcx.lang_items().coerce_unsized_trait() {
1547 let coerce_unsized_info =
1548 self.tcx.at(item.span).coerce_unsized_info(def_id);
1549 record!(self.tables.coerce_unsized_info[def_id] <- coerce_unsized_info);
1553 let polarity = self.tcx.impl_polarity(def_id);
1554 self.tables.impl_polarity.set(def_id.index, polarity);
1556 hir::ItemKind::Trait(..) => {
1557 let trait_def = self.tcx.trait_def(def_id);
1558 record!(self.tables.trait_def[def_id] <- trait_def);
1560 hir::ItemKind::TraitAlias(..) => {
1561 let trait_def = self.tcx.trait_def(def_id);
1562 record!(self.tables.trait_def[def_id] <- trait_def);
1564 hir::ItemKind::ExternCrate(_) | hir::ItemKind::Use(..) => {
1565 bug!("cannot encode info for item {:?}", item)
1567 hir::ItemKind::Static(..)
1568 | hir::ItemKind::Const(..)
1569 | hir::ItemKind::ForeignMod { .. }
1570 | hir::ItemKind::GlobalAsm(..)
1571 | hir::ItemKind::TyAlias(..) => {}
1573 // FIXME(eddyb) there should be a nicer way to do this.
1575 hir::ItemKind::Enum(..) => record_array!(self.tables.children[def_id] <-
1576 self.tcx.adt_def(def_id).variants().iter().map(|v| {
1577 assert!(v.def_id.is_local());
1581 hir::ItemKind::Struct(..) | hir::ItemKind::Union(..) => {
1582 record_array!(self.tables.children[def_id] <-
1583 self.tcx.adt_def(def_id).non_enum_variant().fields.iter().map(|f| {
1584 assert!(f.did.is_local());
1589 hir::ItemKind::Impl { .. } | hir::ItemKind::Trait(..) => {
1590 let associated_item_def_ids = self.tcx.associated_item_def_ids(def_id);
1591 record_array!(self.tables.children[def_id] <-
1592 associated_item_def_ids.iter().map(|&def_id| {
1593 assert!(def_id.is_local());
1600 if let hir::ItemKind::Fn(..) = item.kind {
1601 record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
1602 if tcx.is_intrinsic(def_id) {
1603 self.tables.is_intrinsic.set(def_id.index, ());
1606 if let hir::ItemKind::Impl { .. } = item.kind {
1607 if let Some(trait_ref) = self.tcx.impl_trait_ref(def_id) {
1608 record!(self.tables.impl_trait_ref[def_id] <- trait_ref);
1611 // In some cases, along with the item itself, we also
1612 // encode some sub-items. Usually we want some info from the item
1613 // so it's easier to do that here then to wait until we would encounter
1614 // normally in the visitor walk.
1616 hir::ItemKind::Enum(..) => {
1617 let def = self.tcx.adt_def(item.def_id.to_def_id());
1618 for (i, variant) in def.variants().iter_enumerated() {
1619 self.encode_enum_variant_info(def, i);
1621 if let Some(_ctor_def_id) = variant.ctor_def_id {
1622 self.encode_enum_variant_ctor(def, i);
1626 hir::ItemKind::Struct(ref struct_def, _) => {
1627 let def = self.tcx.adt_def(item.def_id.to_def_id());
1628 // If the struct has a constructor, encode it.
1629 if let Some(ctor_hir_id) = struct_def.ctor_hir_id() {
1630 let ctor_def_id = self.tcx.hir().local_def_id(ctor_hir_id);
1631 self.encode_struct_ctor(def, ctor_def_id.to_def_id());
1634 hir::ItemKind::Impl { .. } => {
1635 for &trait_item_def_id in
1636 self.tcx.associated_item_def_ids(item.def_id.to_def_id()).iter()
1638 self.encode_info_for_impl_item(trait_item_def_id);
1641 hir::ItemKind::Trait(..) => {
1642 for &item_def_id in self.tcx.associated_item_def_ids(item.def_id.to_def_id()).iter()
1644 self.encode_info_for_trait_item(item_def_id);
1651 fn encode_info_for_closure(&mut self, hir_id: hir::HirId) {
1652 let def_id = self.tcx.hir().local_def_id(hir_id);
1653 debug!("EncodeContext::encode_info_for_closure({:?})", def_id);
1654 // NOTE(eddyb) `tcx.type_of(def_id)` isn't used because it's fully generic,
1655 // including on the signature, which is inferred in `typeck.
1656 let typeck_result: &'tcx ty::TypeckResults<'tcx> = self.tcx.typeck(def_id);
1657 let ty = typeck_result.node_type(hir_id);
1659 ty::Generator(..) => {
1660 let data = self.tcx.generator_kind(def_id).unwrap();
1661 let generator_diagnostic_data = typeck_result.get_generator_diagnostic_data();
1662 record!(self.tables.generator_kind[def_id.to_def_id()] <- data);
1663 record!(self.tables.generator_diagnostic_data[def_id.to_def_id()] <- generator_diagnostic_data);
1666 ty::Closure(_, substs) => {
1667 record!(self.tables.fn_sig[def_id.to_def_id()] <- substs.as_closure().sig());
1670 _ => bug!("closure that is neither generator nor closure"),
1674 fn encode_native_libraries(&mut self) -> LazyArray<NativeLib> {
1675 empty_proc_macro!(self);
1676 let used_libraries = self.tcx.native_libraries(LOCAL_CRATE);
1677 self.lazy_array(used_libraries.iter())
1680 fn encode_foreign_modules(&mut self) -> LazyArray<ForeignModule> {
1681 empty_proc_macro!(self);
1682 let foreign_modules = self.tcx.foreign_modules(LOCAL_CRATE);
1683 self.lazy_array(foreign_modules.iter().map(|(_, m)| m).cloned())
1686 fn encode_hygiene(&mut self) -> (SyntaxContextTable, ExpnDataTable, ExpnHashTable) {
1687 let mut syntax_contexts: TableBuilder<_, _> = Default::default();
1688 let mut expn_data_table: TableBuilder<_, _> = Default::default();
1689 let mut expn_hash_table: TableBuilder<_, _> = Default::default();
1691 self.hygiene_ctxt.encode(
1692 &mut (&mut *self, &mut syntax_contexts, &mut expn_data_table, &mut expn_hash_table),
1693 |(this, syntax_contexts, _, _), index, ctxt_data| {
1694 syntax_contexts.set(index, this.lazy(ctxt_data));
1696 |(this, _, expn_data_table, expn_hash_table), index, expn_data, hash| {
1697 if let Some(index) = index.as_local() {
1698 expn_data_table.set(index.as_raw(), this.lazy(expn_data));
1699 expn_hash_table.set(index.as_raw(), this.lazy(hash));
1705 syntax_contexts.encode(&mut self.opaque),
1706 expn_data_table.encode(&mut self.opaque),
1707 expn_hash_table.encode(&mut self.opaque),
1711 fn encode_proc_macros(&mut self) -> Option<ProcMacroData> {
1712 let is_proc_macro = self.tcx.sess.crate_types().contains(&CrateType::ProcMacro);
1715 let hir = tcx.hir();
1717 let proc_macro_decls_static = tcx.proc_macro_decls_static(()).unwrap().local_def_index;
1718 let stability = tcx.lookup_stability(CRATE_DEF_ID);
1720 self.lazy_array(tcx.resolutions(()).proc_macros.iter().map(|p| p.local_def_index));
1721 let spans = self.tcx.sess.parse_sess.proc_macro_quoted_spans();
1722 for (i, span) in spans.into_iter().enumerate() {
1723 let span = self.lazy(span);
1724 self.tables.proc_macro_quoted_spans.set(i, span);
1727 self.tables.opt_def_kind.set(LOCAL_CRATE.as_def_id().index, DefKind::Mod);
1728 record!(self.tables.def_span[LOCAL_CRATE.as_def_id()] <- tcx.def_span(LOCAL_CRATE.as_def_id()));
1729 self.encode_attrs(LOCAL_CRATE.as_def_id().expect_local());
1730 record!(self.tables.visibility[LOCAL_CRATE.as_def_id()] <- tcx.visibility(LOCAL_CRATE.as_def_id()));
1731 if let Some(stability) = stability {
1732 record!(self.tables.lookup_stability[LOCAL_CRATE.as_def_id()] <- stability);
1734 self.encode_deprecation(LOCAL_CRATE.as_def_id());
1736 // Normally, this information is encoded when we walk the items
1737 // defined in this crate. However, we skip doing that for proc-macro crates,
1738 // so we manually encode just the information that we need
1739 for &proc_macro in &tcx.resolutions(()).proc_macros {
1740 let id = proc_macro;
1741 let proc_macro = hir.local_def_id_to_hir_id(proc_macro);
1742 let mut name = hir.name(proc_macro);
1743 let span = hir.span(proc_macro);
1744 // Proc-macros may have attributes like `#[allow_internal_unstable]`,
1745 // so downstream crates need access to them.
1746 let attrs = hir.attrs(proc_macro);
1747 let macro_kind = if tcx.sess.contains_name(attrs, sym::proc_macro) {
1749 } else if tcx.sess.contains_name(attrs, sym::proc_macro_attribute) {
1751 } else if let Some(attr) = tcx.sess.find_by_name(attrs, sym::proc_macro_derive) {
1752 // This unwrap chain should have been checked by the proc-macro harness.
1753 name = attr.meta_item_list().unwrap()[0]
1761 bug!("Unknown proc-macro type for item {:?}", id);
1764 let mut def_key = self.tcx.hir().def_key(id);
1765 def_key.disambiguated_data.data = DefPathData::MacroNs(name);
1767 let def_id = id.to_def_id();
1768 self.tables.opt_def_kind.set(def_id.index, DefKind::Macro(macro_kind));
1769 self.tables.proc_macro.set(def_id.index, macro_kind);
1770 self.encode_attrs(id);
1771 record!(self.tables.def_keys[def_id] <- def_key);
1772 record!(self.tables.def_ident_span[def_id] <- span);
1773 record!(self.tables.def_span[def_id] <- span);
1774 record!(self.tables.visibility[def_id] <- ty::Visibility::Public);
1775 if let Some(stability) = stability {
1776 record!(self.tables.lookup_stability[def_id] <- stability);
1780 Some(ProcMacroData { proc_macro_decls_static, stability, macros })
1786 fn encode_debugger_visualizers(&mut self) -> LazyArray<DebuggerVisualizerFile> {
1787 empty_proc_macro!(self);
1788 self.lazy_array(self.tcx.debugger_visualizers(LOCAL_CRATE).iter())
1791 fn encode_crate_deps(&mut self) -> LazyArray<CrateDep> {
1792 empty_proc_macro!(self);
1799 let dep = CrateDep {
1800 name: self.tcx.crate_name(cnum),
1801 hash: self.tcx.crate_hash(cnum),
1802 host_hash: self.tcx.crate_host_hash(cnum),
1803 kind: self.tcx.dep_kind(cnum),
1804 extra_filename: self.tcx.extra_filename(cnum).clone(),
1808 .collect::<Vec<_>>();
1811 // Sanity-check the crate numbers
1812 let mut expected_cnum = 1;
1813 for &(n, _) in &deps {
1814 assert_eq!(n, CrateNum::new(expected_cnum));
1819 // We're just going to write a list of crate 'name-hash-version's, with
1820 // the assumption that they are numbered 1 to n.
1821 // FIXME (#2166): This is not nearly enough to support correct versioning
1822 // but is enough to get transitive crate dependencies working.
1823 self.lazy_array(deps.iter().map(|&(_, ref dep)| dep))
1826 fn encode_lib_features(&mut self) -> LazyArray<(Symbol, Option<Symbol>)> {
1827 empty_proc_macro!(self);
1829 let lib_features = tcx.lib_features(());
1830 self.lazy_array(lib_features.to_vec())
1833 fn encode_stability_implications(&mut self) -> LazyArray<(Symbol, Symbol)> {
1834 empty_proc_macro!(self);
1836 let implications = tcx.stability_implications(LOCAL_CRATE);
1837 self.lazy_array(implications.iter().map(|(k, v)| (*k, *v)))
1840 fn encode_diagnostic_items(&mut self) -> LazyArray<(Symbol, DefIndex)> {
1841 empty_proc_macro!(self);
1843 let diagnostic_items = &tcx.diagnostic_items(LOCAL_CRATE).name_to_id;
1844 self.lazy_array(diagnostic_items.iter().map(|(&name, def_id)| (name, def_id.index)))
1847 fn encode_lang_items(&mut self) -> LazyArray<(DefIndex, usize)> {
1848 empty_proc_macro!(self);
1850 let lang_items = tcx.lang_items();
1851 let lang_items = lang_items.items().iter();
1852 self.lazy_array(lang_items.enumerate().filter_map(|(i, &opt_def_id)| {
1853 if let Some(def_id) = opt_def_id {
1854 if def_id.is_local() {
1855 return Some((def_id.index, i));
1862 fn encode_lang_items_missing(&mut self) -> LazyArray<lang_items::LangItem> {
1863 empty_proc_macro!(self);
1865 self.lazy_array(&tcx.lang_items().missing)
1868 fn encode_traits(&mut self) -> LazyArray<DefIndex> {
1869 empty_proc_macro!(self);
1870 self.lazy_array(self.tcx.traits_in_crate(LOCAL_CRATE).iter().map(|def_id| def_id.index))
1873 /// Encodes an index, mapping each trait to its (local) implementations.
1874 fn encode_impls(&mut self) -> LazyArray<TraitImpls> {
1875 debug!("EncodeContext::encode_traits_and_impls()");
1876 empty_proc_macro!(self);
1878 let mut fx_hash_map: FxHashMap<DefId, Vec<(DefIndex, Option<SimplifiedType>)>> =
1879 FxHashMap::default();
1881 for id in tcx.hir().items() {
1882 if matches!(tcx.def_kind(id.def_id), DefKind::Impl) {
1883 if let Some(trait_ref) = tcx.impl_trait_ref(id.def_id.to_def_id()) {
1884 let simplified_self_ty = fast_reject::simplify_type(
1886 trait_ref.self_ty(),
1887 TreatParams::AsInfer,
1891 .entry(trait_ref.def_id)
1893 .push((id.def_id.local_def_index, simplified_self_ty));
1898 let mut all_impls: Vec<_> = fx_hash_map.into_iter().collect();
1900 // Bring everything into deterministic order for hashing
1901 all_impls.sort_by_cached_key(|&(trait_def_id, _)| tcx.def_path_hash(trait_def_id));
1903 let all_impls: Vec<_> = all_impls
1905 .map(|(trait_def_id, mut impls)| {
1906 // Bring everything into deterministic order for hashing
1907 impls.sort_by_cached_key(|&(index, _)| {
1908 tcx.hir().def_path_hash(LocalDefId { local_def_index: index })
1912 trait_id: (trait_def_id.krate.as_u32(), trait_def_id.index),
1913 impls: self.lazy_array(&impls),
1918 self.lazy_array(&all_impls)
1921 fn encode_incoherent_impls(&mut self) -> LazyArray<IncoherentImpls> {
1922 debug!("EncodeContext::encode_traits_and_impls()");
1923 empty_proc_macro!(self);
1925 let mut all_impls: Vec<_> = tcx.crate_inherent_impls(()).incoherent_impls.iter().collect();
1926 tcx.with_stable_hashing_context(|mut ctx| {
1927 all_impls.sort_by_cached_key(|&(&simp, _)| {
1928 let mut hasher = StableHasher::new();
1929 simp.hash_stable(&mut ctx, &mut hasher);
1930 hasher.finish::<Fingerprint>()
1933 let all_impls: Vec<_> = all_impls
1935 .map(|(&simp, impls)| {
1936 let mut impls: Vec<_> =
1937 impls.into_iter().map(|def_id| def_id.local_def_index).collect();
1938 impls.sort_by_cached_key(|&local_def_index| {
1939 tcx.hir().def_path_hash(LocalDefId { local_def_index })
1942 IncoherentImpls { self_ty: simp, impls: self.lazy_array(impls) }
1946 self.lazy_array(&all_impls)
1949 // Encodes all symbols exported from this crate into the metadata.
1951 // This pass is seeded off the reachability list calculated in the
1952 // middle::reachable module but filters out items that either don't have a
1953 // symbol associated with them (they weren't translated) or if they're an FFI
1954 // definition (as that's not defined in this crate).
1955 fn encode_exported_symbols(
1957 exported_symbols: &[(ExportedSymbol<'tcx>, SymbolExportInfo)],
1958 ) -> LazyArray<(ExportedSymbol<'static>, SymbolExportInfo)> {
1959 empty_proc_macro!(self);
1960 // The metadata symbol name is special. It should not show up in
1961 // downstream crates.
1962 let metadata_symbol_name = SymbolName::new(self.tcx, &metadata_symbol_name(self.tcx));
1967 .filter(|&&(ref exported_symbol, _)| match *exported_symbol {
1968 ExportedSymbol::NoDefId(symbol_name) => symbol_name != metadata_symbol_name,
1975 fn encode_dylib_dependency_formats(&mut self) -> LazyArray<Option<LinkagePreference>> {
1976 empty_proc_macro!(self);
1977 let formats = self.tcx.dependency_formats(());
1978 for (ty, arr) in formats.iter() {
1979 if *ty != CrateType::Dylib {
1982 return self.lazy_array(arr.iter().map(|slot| match *slot {
1983 Linkage::NotLinked | Linkage::IncludedFromDylib => None,
1985 Linkage::Dynamic => Some(LinkagePreference::RequireDynamic),
1986 Linkage::Static => Some(LinkagePreference::RequireStatic),
1992 fn encode_info_for_foreign_item(&mut self, def_id: DefId, nitem: &hir::ForeignItem<'_>) {
1995 debug!("EncodeContext::encode_info_for_foreign_item({:?})", def_id);
1998 hir::ForeignItemKind::Fn(_, ref names, _) => {
1999 self.tables.asyncness.set(def_id.index, hir::IsAsync::NotAsync);
2000 record_array!(self.tables.fn_arg_names[def_id] <- *names);
2001 let constness = if self.tcx.is_const_fn_raw(def_id) {
2002 hir::Constness::Const
2004 hir::Constness::NotConst
2006 self.tables.constness.set(def_id.index, constness);
2007 record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
2009 hir::ForeignItemKind::Static(..) | hir::ForeignItemKind::Type => {}
2011 if let hir::ForeignItemKind::Fn(..) = nitem.kind {
2012 if tcx.is_intrinsic(def_id) {
2013 self.tables.is_intrinsic.set(def_id.index, ());
2019 // FIXME(eddyb) make metadata encoding walk over all definitions, instead of HIR.
2020 impl<'a, 'tcx> Visitor<'tcx> for EncodeContext<'a, 'tcx> {
2021 type NestedFilter = nested_filter::OnlyBodies;
2023 fn nested_visit_map(&mut self) -> Self::Map {
2026 fn visit_expr(&mut self, ex: &'tcx hir::Expr<'tcx>) {
2027 intravisit::walk_expr(self, ex);
2028 self.encode_info_for_expr(ex);
2030 fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
2031 intravisit::walk_item(self, item);
2033 hir::ItemKind::ExternCrate(_) | hir::ItemKind::Use(..) => {} // ignore these
2034 _ => self.encode_info_for_item(item.def_id.to_def_id(), item),
2037 fn visit_foreign_item(&mut self, ni: &'tcx hir::ForeignItem<'tcx>) {
2038 intravisit::walk_foreign_item(self, ni);
2039 self.encode_info_for_foreign_item(ni.def_id.to_def_id(), ni);
2041 fn visit_generics(&mut self, generics: &'tcx hir::Generics<'tcx>) {
2042 intravisit::walk_generics(self, generics);
2043 self.encode_info_for_generics(generics);
2047 impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
2048 fn encode_info_for_generics(&mut self, generics: &hir::Generics<'tcx>) {
2049 for param in generics.params {
2050 let def_id = self.tcx.hir().local_def_id(param.hir_id);
2052 hir::GenericParamKind::Lifetime { .. } | hir::GenericParamKind::Type { .. } => {}
2053 hir::GenericParamKind::Const { ref default, .. } => {
2054 let def_id = def_id.to_def_id();
2055 if default.is_some() {
2056 record!(self.tables.const_param_default[def_id] <- self.tcx.const_param_default(def_id))
2063 fn encode_info_for_expr(&mut self, expr: &hir::Expr<'_>) {
2064 if let hir::ExprKind::Closure { .. } = expr.kind {
2065 self.encode_info_for_closure(expr.hir_id);
2070 /// Used to prefetch queries which will be needed later by metadata encoding.
2071 /// Only a subset of the queries are actually prefetched to keep this code smaller.
2072 fn prefetch_mir(tcx: TyCtxt<'_>) {
2073 if !tcx.sess.opts.output_types.should_codegen() {
2074 // We won't emit MIR, so don't prefetch it.
2078 par_iter(tcx.mir_keys(())).for_each(|&def_id| {
2079 let (encode_const, encode_opt) = should_encode_mir(tcx, def_id);
2082 tcx.ensure().mir_for_ctfe(def_id);
2085 tcx.ensure().optimized_mir(def_id);
2087 if encode_opt || encode_const {
2088 tcx.ensure().promoted_mir(def_id);
2093 // NOTE(eddyb) The following comment was preserved for posterity, even
2094 // though it's no longer relevant as EBML (which uses nested & tagged
2095 // "documents") was replaced with a scheme that can't go out of bounds.
2097 // And here we run into yet another obscure archive bug: in which metadata
2098 // loaded from archives may have trailing garbage bytes. Awhile back one of
2099 // our tests was failing sporadically on the macOS 64-bit builders (both nopt
2100 // and opt) by having ebml generate an out-of-bounds panic when looking at
2103 // Upon investigation it turned out that the metadata file inside of an rlib
2104 // (and ar archive) was being corrupted. Some compilations would generate a
2105 // metadata file which would end in a few extra bytes, while other
2106 // compilations would not have these extra bytes appended to the end. These
2107 // extra bytes were interpreted by ebml as an extra tag, so they ended up
2108 // being interpreted causing the out-of-bounds.
2110 // The root cause of why these extra bytes were appearing was never
2111 // discovered, and in the meantime the solution we're employing is to insert
2112 // the length of the metadata to the start of the metadata. Later on this
2113 // will allow us to slice the metadata to the precise length that we just
2114 // generated regardless of trailing bytes that end up in it.
2116 pub struct EncodedMetadata {
2117 // The declaration order matters because `mmap` should be dropped before `_temp_dir`.
2119 // We need to carry MaybeTempDir to avoid deleting the temporary
2120 // directory while accessing the Mmap.
2121 _temp_dir: Option<MaybeTempDir>,
2124 impl EncodedMetadata {
2126 pub fn from_path(path: PathBuf, temp_dir: Option<MaybeTempDir>) -> std::io::Result<Self> {
2127 let file = std::fs::File::open(&path)?;
2128 let file_metadata = file.metadata()?;
2129 if file_metadata.len() == 0 {
2130 return Ok(Self { mmap: None, _temp_dir: None });
2132 let mmap = unsafe { Some(Mmap::map(file)?) };
2133 Ok(Self { mmap, _temp_dir: temp_dir })
2137 pub fn raw_data(&self) -> &[u8] {
2138 self.mmap.as_ref().map(|mmap| mmap.as_ref()).unwrap_or_default()
2142 impl<S: Encoder> Encodable<S> for EncodedMetadata {
2143 fn encode(&self, s: &mut S) {
2144 let slice = self.raw_data();
2149 impl<D: Decoder> Decodable<D> for EncodedMetadata {
2150 fn decode(d: &mut D) -> Self {
2151 let len = d.read_usize();
2152 let mmap = if len > 0 {
2153 let mut mmap = MmapMut::map_anon(len).unwrap();
2155 (&mut mmap[..]).write(&[d.read_u8()]).unwrap();
2157 mmap.flush().unwrap();
2158 Some(mmap.make_read_only().unwrap())
2163 Self { mmap, _temp_dir: None }
2167 pub fn encode_metadata(tcx: TyCtxt<'_>, path: &Path) {
2168 let _prof_timer = tcx.prof.verbose_generic_activity("generate_crate_metadata");
2170 // Since encoding metadata is not in a query, and nothing is cached,
2171 // there's no need to do dep-graph tracking for any of it.
2172 tcx.dep_graph.assert_ignored();
2175 || encode_metadata_impl(tcx, path),
2177 if tcx.sess.threads() == 1 {
2180 // Prefetch some queries used by metadata encoding.
2181 // This is not necessary for correctness, but is only done for performance reasons.
2182 // It can be removed if it turns out to cause trouble or be detrimental to performance.
2183 join(|| prefetch_mir(tcx), || tcx.exported_symbols(LOCAL_CRATE));
2188 fn encode_metadata_impl(tcx: TyCtxt<'_>, path: &Path) {
2189 let mut encoder = opaque::FileEncoder::new(path)
2190 .unwrap_or_else(|err| tcx.sess.emit_fatal(FailCreateFileEncoder { err }));
2191 encoder.emit_raw_bytes(METADATA_HEADER);
2193 // Will be filled with the root position after encoding everything.
2194 encoder.emit_raw_bytes(&[0, 0, 0, 0]);
2196 let source_map_files = tcx.sess.source_map().files();
2197 let source_file_cache = (source_map_files[0].clone(), 0);
2198 let required_source_files = Some(FxIndexSet::default());
2199 drop(source_map_files);
2201 let hygiene_ctxt = HygieneEncodeContext::default();
2203 let mut ecx = EncodeContext {
2206 feat: tcx.features(),
2207 tables: Default::default(),
2208 lazy_state: LazyState::NoNode,
2209 type_shorthands: Default::default(),
2210 predicate_shorthands: Default::default(),
2212 interpret_allocs: Default::default(),
2213 required_source_files,
2214 is_proc_macro: tcx.sess.crate_types().contains(&CrateType::ProcMacro),
2215 hygiene_ctxt: &hygiene_ctxt,
2216 symbol_table: Default::default(),
2219 // Encode the rustc version string in a predictable location.
2220 rustc_version().encode(&mut ecx);
2222 // Encode all the entries and extra information in the crate,
2223 // culminating in the `CrateRoot` which points to all of it.
2224 let root = ecx.encode_crate_root();
2228 let mut file = ecx.opaque.file();
2229 // We will return to this position after writing the root position.
2230 let pos_before_seek = file.stream_position().unwrap();
2232 // Encode the root position.
2233 let header = METADATA_HEADER.len();
2234 file.seek(std::io::SeekFrom::Start(header as u64))
2235 .unwrap_or_else(|err| tcx.sess.emit_fatal(FailSeekFile { err }));
2236 let pos = root.position.get();
2237 file.write_all(&[(pos >> 24) as u8, (pos >> 16) as u8, (pos >> 8) as u8, (pos >> 0) as u8])
2238 .unwrap_or_else(|err| tcx.sess.emit_fatal(FailWriteFile { err }));
2240 // Return to the position where we are before writing the root position.
2241 file.seek(std::io::SeekFrom::Start(pos_before_seek)).unwrap();
2243 // Record metadata size for self-profiling
2244 tcx.prof.artifact_size(
2247 file.metadata().unwrap().len() as u64,
2251 pub fn provide(providers: &mut Providers) {
2252 *providers = Providers {
2253 traits_in_crate: |tcx, cnum| {
2254 assert_eq!(cnum, LOCAL_CRATE);
2256 let mut traits = Vec::new();
2257 for id in tcx.hir().items() {
2258 if matches!(tcx.def_kind(id.def_id), DefKind::Trait | DefKind::TraitAlias) {
2259 traits.push(id.def_id.to_def_id())
2263 // Bring everything into deterministic order.
2264 traits.sort_by_cached_key(|&def_id| tcx.def_path_hash(def_id));
2265 tcx.arena.alloc_slice(&traits)