1 use crate::dep_graph::{DepNodeIndex, SerializedDepNodeIndex};
3 use crate::hir::def_id::{CrateNum, DefIndex, DefId, LocalDefId, LOCAL_CRATE};
4 use crate::hir::map::definitions::DefPathHash;
5 use crate::ich::{CachingSourceMapView, Fingerprint};
6 use crate::mir::{self, interpret};
7 use crate::mir::interpret::{AllocDecodingSession, AllocDecodingState};
8 use crate::rustc_serialize::{Decodable, Decoder, Encodable, Encoder, opaque,
9 SpecializedDecoder, SpecializedEncoder,
10 UseSpecializedDecodable, UseSpecializedEncodable};
11 use crate::session::{CrateDisambiguator, Session};
12 use crate::ty::{self, Ty};
13 use crate::ty::codec::{self as ty_codec, TyDecoder, TyEncoder};
14 use crate::ty::context::TyCtxt;
15 use crate::util::common::{time, time_ext};
17 use errors::Diagnostic;
18 use rustc_data_structures::fx::FxHashMap;
19 use rustc_data_structures::thin_vec::ThinVec;
20 use rustc_data_structures::sync::{Lrc, Lock, HashMapExt, Once};
21 use rustc_data_structures::indexed_vec::{IndexVec, Idx};
23 use syntax::ast::NodeId;
24 use syntax::source_map::{SourceMap, StableSourceFileId};
25 use syntax_pos::{BytePos, Span, DUMMY_SP, SourceFile};
26 use syntax_pos::hygiene::{Mark, SyntaxContext, ExpnInfo};
28 const TAG_FILE_FOOTER: u128 = 0xC0FFEE_C0FFEE_C0FFEE_C0FFEE_C0FFEE;
30 const TAG_CLEAR_CROSS_CRATE_CLEAR: u8 = 0;
31 const TAG_CLEAR_CROSS_CRATE_SET: u8 = 1;
33 const TAG_NO_EXPANSION_INFO: u8 = 0;
34 const TAG_EXPANSION_INFO_SHORTHAND: u8 = 1;
35 const TAG_EXPANSION_INFO_INLINE: u8 = 2;
37 const TAG_VALID_SPAN: u8 = 0;
38 const TAG_INVALID_SPAN: u8 = 1;
40 /// `OnDiskCache` provides an interface to incr. comp. data cached from the
41 /// previous compilation session. This data will eventually include the results
42 /// of a few selected queries (like `typeck_tables_of` and `mir_optimized`) and
43 /// any diagnostics that have been emitted during a query.
44 pub struct OnDiskCache<'sess> {
46 // The complete cache data in serialized form.
47 serialized_data: Vec<u8>,
49 // This field collects all Diagnostics emitted during the current
50 // compilation session.
51 current_diagnostics: Lock<FxHashMap<DepNodeIndex, Vec<Diagnostic>>>,
53 prev_cnums: Vec<(u32, String, CrateDisambiguator)>,
54 cnum_map: Once<IndexVec<CrateNum, Option<CrateNum>>>,
56 source_map: &'sess SourceMap,
57 file_index_to_stable_id: FxHashMap<SourceFileIndex, StableSourceFileId>,
59 // These two fields caches that are populated lazily during decoding.
60 file_index_to_file: Lock<FxHashMap<SourceFileIndex, Lrc<SourceFile>>>,
61 synthetic_expansion_infos: Lock<FxHashMap<AbsoluteBytePos, SyntaxContext>>,
63 // A map from dep-node to the position of the cached query result in
65 query_result_index: FxHashMap<SerializedDepNodeIndex, AbsoluteBytePos>,
67 // A map from dep-node to the position of any associated diagnostics in
69 prev_diagnostics_index: FxHashMap<SerializedDepNodeIndex, AbsoluteBytePos>,
71 alloc_decoding_state: AllocDecodingState,
74 // This type is used only for (de-)serialization.
75 #[derive(RustcEncodable, RustcDecodable)]
77 file_index_to_stable_id: FxHashMap<SourceFileIndex, StableSourceFileId>,
78 prev_cnums: Vec<(u32, String, CrateDisambiguator)>,
79 query_result_index: EncodedQueryResultIndex,
80 diagnostics_index: EncodedQueryResultIndex,
81 // the location of all allocations
82 interpret_alloc_index: Vec<u32>,
85 type EncodedQueryResultIndex = Vec<(SerializedDepNodeIndex, AbsoluteBytePos)>;
86 type EncodedDiagnosticsIndex = Vec<(SerializedDepNodeIndex, AbsoluteBytePos)>;
87 type EncodedDiagnostics = Vec<Diagnostic>;
89 #[derive(Copy, Clone, PartialEq, Eq, Hash, Debug, RustcEncodable, RustcDecodable)]
90 struct SourceFileIndex(u32);
92 #[derive(Copy, Clone, Debug, Hash, Eq, PartialEq, RustcEncodable, RustcDecodable)]
93 struct AbsoluteBytePos(u32);
95 impl AbsoluteBytePos {
96 fn new(pos: usize) -> AbsoluteBytePos {
97 debug_assert!(pos <= ::std::u32::MAX as usize);
98 AbsoluteBytePos(pos as u32)
101 fn to_usize(self) -> usize {
106 impl<'sess> OnDiskCache<'sess> {
107 /// Creates a new OnDiskCache instance from the serialized data in `data`.
108 pub fn new(sess: &'sess Session, data: Vec<u8>, start_pos: usize) -> OnDiskCache<'sess> {
109 debug_assert!(sess.opts.incremental.is_some());
111 // Wrapping in a scope so we can borrow `data`
112 let footer: Footer = {
113 let mut decoder = opaque::Decoder::new(&data[..], start_pos);
115 // Decode the *position* of the footer which can be found in the
116 // last 8 bytes of the file.
117 decoder.set_position(data.len() - IntEncodedWithFixedSize::ENCODED_SIZE);
118 let query_result_index_pos = IntEncodedWithFixedSize::decode(&mut decoder)
119 .expect("Error while trying to decode query result index position.")
122 // Decoder the file footer which contains all the lookup tables, etc.
123 decoder.set_position(query_result_index_pos);
124 decode_tagged(&mut decoder, TAG_FILE_FOOTER)
125 .expect("Error while trying to decode query result index position.")
129 serialized_data: data,
130 file_index_to_stable_id: footer.file_index_to_stable_id,
131 file_index_to_file: Default::default(),
132 prev_cnums: footer.prev_cnums,
133 cnum_map: Once::new(),
134 source_map: sess.source_map(),
135 current_diagnostics: Default::default(),
136 query_result_index: footer.query_result_index.into_iter().collect(),
137 prev_diagnostics_index: footer.diagnostics_index.into_iter().collect(),
138 synthetic_expansion_infos: Default::default(),
139 alloc_decoding_state: AllocDecodingState::new(footer.interpret_alloc_index),
143 pub fn new_empty(source_map: &'sess SourceMap) -> OnDiskCache<'sess> {
145 serialized_data: Vec::new(),
146 file_index_to_stable_id: Default::default(),
147 file_index_to_file: Default::default(),
149 cnum_map: Once::new(),
151 current_diagnostics: Default::default(),
152 query_result_index: Default::default(),
153 prev_diagnostics_index: Default::default(),
154 synthetic_expansion_infos: Default::default(),
155 alloc_decoding_state: AllocDecodingState::new(Vec::new()),
159 pub fn serialize<'tcx, E>(
161 tcx: TyCtxt<'tcx, 'tcx>,
163 ) -> Result<(), E::Error>
165 E: ty_codec::TyEncoder,
167 // Serializing the DepGraph should not modify it:
168 tcx.dep_graph.with_ignore(|| {
169 // Allocate SourceFileIndices
170 let (file_to_file_index, file_index_to_stable_id) = {
171 let files = tcx.sess.source_map().files();
172 let mut file_to_file_index = FxHashMap::with_capacity_and_hasher(
173 files.len(), Default::default());
174 let mut file_index_to_stable_id = FxHashMap::with_capacity_and_hasher(
175 files.len(), Default::default());
177 for (index, file) in files.iter().enumerate() {
178 let index = SourceFileIndex(index as u32);
179 let file_ptr: *const SourceFile = &**file as *const _;
180 file_to_file_index.insert(file_ptr, index);
181 file_index_to_stable_id.insert(index, StableSourceFileId::new(&file));
184 (file_to_file_index, file_index_to_stable_id)
187 let mut encoder = CacheEncoder {
190 type_shorthands: Default::default(),
191 predicate_shorthands: Default::default(),
192 expn_info_shorthands: Default::default(),
193 interpret_allocs: Default::default(),
194 interpret_allocs_inverse: Vec::new(),
195 source_map: CachingSourceMapView::new(tcx.sess.source_map()),
199 // Load everything into memory so we can write it out to the on-disk
200 // cache. The vast majority of cacheable query results should already
201 // be in memory, so this should be a cheap operation.
202 tcx.dep_graph.exec_cache_promotions(tcx);
204 // Encode query results
205 let mut query_result_index = EncodedQueryResultIndex::new();
207 time(tcx.sess, "encode query results", || {
208 use crate::ty::query::queries::*;
209 let enc = &mut encoder;
210 let qri = &mut query_result_index;
212 encode_query_results::<type_of<'_>, _>(tcx, enc, qri)?;
213 encode_query_results::<generics_of<'_>, _>(tcx, enc, qri)?;
214 encode_query_results::<predicates_of<'_>, _>(tcx, enc, qri)?;
215 encode_query_results::<used_trait_imports<'_>, _>(tcx, enc, qri)?;
216 encode_query_results::<typeck_tables_of<'_>, _>(tcx, enc, qri)?;
217 encode_query_results::<codegen_fulfill_obligation<'_>, _>(tcx, enc, qri)?;
218 encode_query_results::<optimized_mir<'_>, _>(tcx, enc, qri)?;
219 encode_query_results::<unsafety_check_result<'_>, _>(tcx, enc, qri)?;
220 encode_query_results::<borrowck<'_>, _>(tcx, enc, qri)?;
221 encode_query_results::<mir_borrowck<'_>, _>(tcx, enc, qri)?;
222 encode_query_results::<mir_const_qualif<'_>, _>(tcx, enc, qri)?;
223 encode_query_results::<const_is_rvalue_promotable_to_static<'_>, _>(tcx, enc, qri)?;
224 encode_query_results::<symbol_name<'_>, _>(tcx, enc, qri)?;
225 encode_query_results::<check_match<'_>, _>(tcx, enc, qri)?;
226 encode_query_results::<codegen_fn_attrs<'_>, _>(tcx, enc, qri)?;
227 encode_query_results::<specialization_graph_of<'_>, _>(tcx, enc, qri)?;
229 // const eval is special, it only encodes successfully evaluated constants
230 use crate::ty::query::QueryAccessors;
231 let cache = const_eval::query_cache(tcx).borrow();
232 assert!(cache.active.is_empty());
233 for (key, entry) in cache.results.iter() {
234 use crate::ty::query::config::QueryDescription;
235 if const_eval::cache_on_disk(tcx, key.clone()) {
236 if let Ok(ref value) = entry.value {
237 let dep_node = SerializedDepNodeIndex::new(entry.index.index());
239 // Record position of the cache entry
240 qri.push((dep_node, AbsoluteBytePos::new(enc.position())));
242 // Encode the type check tables with the SerializedDepNodeIndex
244 enc.encode_tagged(dep_node, value)?;
252 // Encode diagnostics
253 let diagnostics_index: EncodedDiagnosticsIndex = self.current_diagnostics.borrow()
255 .map(|(dep_node_index, diagnostics)|
257 let pos = AbsoluteBytePos::new(encoder.position());
258 // Let's make sure we get the expected type here:
259 let diagnostics: &EncodedDiagnostics = diagnostics;
260 let dep_node_index = SerializedDepNodeIndex::new(dep_node_index.index());
261 encoder.encode_tagged(dep_node_index, diagnostics)?;
263 Ok((dep_node_index, pos))
265 .collect::<Result<_, _>>()?;
267 let interpret_alloc_index = {
268 let mut interpret_alloc_index = Vec::new();
271 let new_n = encoder.interpret_allocs_inverse.len();
272 // if we have found new ids, serialize those, too
277 interpret_alloc_index.reserve(new_n - n);
278 for idx in n..new_n {
279 let id = encoder.interpret_allocs_inverse[idx];
280 let pos = encoder.position() as u32;
281 interpret_alloc_index.push(pos);
282 interpret::specialized_encode_alloc_id(
290 interpret_alloc_index
293 let sorted_cnums = sorted_cnums_including_local_crate(tcx);
294 let prev_cnums: Vec<_> = sorted_cnums.iter().map(|&cnum| {
295 let crate_name = tcx.original_crate_name(cnum).as_str().to_string();
296 let crate_disambiguator = tcx.crate_disambiguator(cnum);
297 (cnum.as_u32(), crate_name, crate_disambiguator)
300 // Encode the file footer
301 let footer_pos = encoder.position() as u64;
302 encoder.encode_tagged(TAG_FILE_FOOTER, &Footer {
303 file_index_to_stable_id,
307 interpret_alloc_index,
310 // Encode the position of the footer as the last 8 bytes of the
311 // file so we know where to look for it.
312 IntEncodedWithFixedSize(footer_pos).encode(encoder.encoder)?;
314 // DO NOT WRITE ANYTHING TO THE ENCODER AFTER THIS POINT! The address
315 // of the footer must be the last thing in the data stream.
319 fn sorted_cnums_including_local_crate(tcx: TyCtxt<'_, '_>) -> Vec<CrateNum> {
320 let mut cnums = vec![LOCAL_CRATE];
321 cnums.extend_from_slice(&tcx.crates()[..]);
322 cnums.sort_unstable();
323 // Just to be sure...
330 /// Loads a diagnostic emitted during the previous compilation session.
331 pub fn load_diagnostics<'tcx>(
333 tcx: TyCtxt<'tcx, 'tcx>,
334 dep_node_index: SerializedDepNodeIndex,
335 ) -> Vec<Diagnostic> {
336 let diagnostics: Option<EncodedDiagnostics> = self.load_indexed(
339 &self.prev_diagnostics_index,
342 diagnostics.unwrap_or_default()
345 /// Stores a diagnostic emitted during the current compilation session.
346 /// Anything stored like this will be available via `load_diagnostics` in
347 /// the next compilation session.
350 pub fn store_diagnostics(&self,
351 dep_node_index: DepNodeIndex,
352 diagnostics: ThinVec<Diagnostic>) {
353 let mut current_diagnostics = self.current_diagnostics.borrow_mut();
354 let prev = current_diagnostics.insert(dep_node_index, diagnostics.into());
355 debug_assert!(prev.is_none());
358 /// Returns the cached query result if there is something in the cache for
359 /// the given `SerializedDepNodeIndex`; otherwise returns `None`.
360 pub fn try_load_query_result<'tcx, T>(
362 tcx: TyCtxt<'tcx, 'tcx>,
363 dep_node_index: SerializedDepNodeIndex,
368 self.load_indexed(tcx,
370 &self.query_result_index,
374 /// Stores a diagnostic emitted during computation of an anonymous query.
375 /// Since many anonymous queries can share the same `DepNode`, we aggregate
376 /// them -- as opposed to regular queries where we assume that there is a
377 /// 1:1 relationship between query-key and `DepNode`.
380 pub fn store_diagnostics_for_anon_node(&self,
381 dep_node_index: DepNodeIndex,
382 diagnostics: ThinVec<Diagnostic>) {
383 let mut current_diagnostics = self.current_diagnostics.borrow_mut();
385 let x = current_diagnostics.entry(dep_node_index).or_insert(Vec::new());
387 x.extend(Into::<Vec<_>>::into(diagnostics));
390 fn load_indexed<'tcx, T>(
392 tcx: TyCtxt<'tcx, 'tcx>,
393 dep_node_index: SerializedDepNodeIndex,
394 index: &FxHashMap<SerializedDepNodeIndex, AbsoluteBytePos>,
395 debug_tag: &'static str,
400 let pos = index.get(&dep_node_index).cloned()?;
402 // Initialize the cnum_map using the value from the thread which finishes the closure first
403 self.cnum_map.init_nonlocking_same(|| {
404 Self::compute_cnum_map(tcx, &self.prev_cnums[..])
407 let mut decoder = CacheDecoder {
409 opaque: opaque::Decoder::new(&self.serialized_data[..], pos.to_usize()),
410 source_map: self.source_map,
411 cnum_map: self.cnum_map.get(),
412 file_index_to_file: &self.file_index_to_file,
413 file_index_to_stable_id: &self.file_index_to_stable_id,
414 synthetic_expansion_infos: &self.synthetic_expansion_infos,
415 alloc_decoding_session: self.alloc_decoding_state.new_decoding_session(),
418 match decode_tagged(&mut decoder, dep_node_index) {
423 bug!("Could not decode cached {}: {}", debug_tag, e)
428 // This function builds mapping from previous-session-CrateNum to
429 // current-session-CrateNum. There might be CrateNums from the previous
430 // Session that don't occur in the current one. For these, the mapping
434 prev_cnums: &[(u32, String, CrateDisambiguator)],
435 ) -> IndexVec<CrateNum, Option<CrateNum>> {
436 tcx.dep_graph.with_ignore(|| {
437 let current_cnums = tcx.all_crate_nums(LOCAL_CRATE).iter().map(|&cnum| {
438 let crate_name = tcx.original_crate_name(cnum)
440 let crate_disambiguator = tcx.crate_disambiguator(cnum);
441 ((crate_name, crate_disambiguator), cnum)
442 }).collect::<FxHashMap<_,_>>();
444 let map_size = prev_cnums.iter()
445 .map(|&(cnum, ..)| cnum)
448 let mut map = IndexVec::from_elem_n(None, map_size as usize);
450 for &(prev_cnum, ref crate_name, crate_disambiguator) in prev_cnums {
451 let key = (crate_name.clone(), crate_disambiguator);
452 map[CrateNum::from_u32(prev_cnum)] = current_cnums.get(&key).cloned();
455 map[LOCAL_CRATE] = Some(LOCAL_CRATE);
461 //- DECODING -------------------------------------------------------------------
463 /// A decoder that can read the incr. comp. cache. It is similar to the one
464 /// we use for crate metadata decoding in that it can rebase spans and
465 /// eventually will also handle things that contain `Ty` instances.
466 struct CacheDecoder<'a, 'tcx> {
467 tcx: TyCtxt<'tcx, 'tcx>,
468 opaque: opaque::Decoder<'a>,
469 source_map: &'a SourceMap,
470 cnum_map: &'a IndexVec<CrateNum, Option<CrateNum>>,
471 synthetic_expansion_infos: &'a Lock<FxHashMap<AbsoluteBytePos, SyntaxContext>>,
472 file_index_to_file: &'a Lock<FxHashMap<SourceFileIndex, Lrc<SourceFile>>>,
473 file_index_to_stable_id: &'a FxHashMap<SourceFileIndex, StableSourceFileId>,
474 alloc_decoding_session: AllocDecodingSession<'a>,
477 impl<'a, 'tcx> CacheDecoder<'a, 'tcx> {
478 fn file_index_to_file(&self, index: SourceFileIndex) -> Lrc<SourceFile> {
480 ref file_index_to_file,
481 ref file_index_to_stable_id,
486 file_index_to_file.borrow_mut().entry(index).or_insert_with(|| {
487 let stable_id = file_index_to_stable_id[&index];
488 source_map.source_file_by_stable_id(stable_id)
489 .expect("Failed to lookup SourceFile in new context.")
494 trait DecoderWithPosition: Decoder {
495 fn position(&self) -> usize;
498 impl<'a> DecoderWithPosition for opaque::Decoder<'a> {
499 fn position(&self) -> usize {
504 impl<'a, 'tcx> DecoderWithPosition for CacheDecoder<'a, 'tcx> {
505 fn position(&self) -> usize {
506 self.opaque.position()
510 // Decode something that was encoded with encode_tagged() and verify that the
511 // tag matches and the correct amount of bytes was read.
512 fn decode_tagged<'a, 'tcx, D, T, V>(decoder: &mut D,
514 -> Result<V, D::Error>
515 where T: Decodable + Eq + ::std::fmt::Debug,
517 D: DecoderWithPosition,
520 let start_pos = decoder.position();
522 let actual_tag = T::decode(decoder)?;
523 assert_eq!(actual_tag, expected_tag);
524 let value = V::decode(decoder)?;
525 let end_pos = decoder.position();
527 let expected_len: u64 = Decodable::decode(decoder)?;
528 assert_eq!((end_pos - start_pos) as u64, expected_len);
533 impl<'a, 'tcx> ty_codec::TyDecoder<'tcx> for CacheDecoder<'a, 'tcx> {
535 fn tcx(&self) -> TyCtxt<'tcx, 'tcx> {
540 fn position(&self) -> usize {
541 self.opaque.position()
545 fn peek_byte(&self) -> u8 {
546 self.opaque.data[self.opaque.position()]
549 fn cached_ty_for_shorthand<F>(&mut self,
552 -> Result<Ty<'tcx>, Self::Error>
553 where F: FnOnce(&mut Self) -> Result<Ty<'tcx>, Self::Error>
555 let tcx = self.tcx();
557 let cache_key = ty::CReaderCacheKey {
558 cnum: CrateNum::ReservedForIncrCompCache,
562 if let Some(&ty) = tcx.rcache.borrow().get(&cache_key) {
566 let ty = or_insert_with(self)?;
567 // This may overwrite the entry, but it should overwrite with the same value
568 tcx.rcache.borrow_mut().insert_same(cache_key, ty);
572 fn with_position<F, R>(&mut self, pos: usize, f: F) -> R
573 where F: FnOnce(&mut Self) -> R
575 debug_assert!(pos < self.opaque.data.len());
577 let new_opaque = opaque::Decoder::new(self.opaque.data, pos);
578 let old_opaque = mem::replace(&mut self.opaque, new_opaque);
580 self.opaque = old_opaque;
584 fn map_encoded_cnum_to_current(&self, cnum: CrateNum) -> CrateNum {
585 self.cnum_map[cnum].unwrap_or_else(|| {
586 bug!("Could not find new CrateNum for {:?}", cnum)
591 implement_ty_decoder!(CacheDecoder<'a, 'tcx>);
593 impl<'a, 'tcx> SpecializedDecoder<interpret::AllocId> for CacheDecoder<'a, 'tcx> {
594 fn specialized_decode(&mut self) -> Result<interpret::AllocId, Self::Error> {
595 let alloc_decoding_session = self.alloc_decoding_session;
596 alloc_decoding_session.decode_alloc_id(self)
600 impl<'a, 'tcx> SpecializedDecoder<Span> for CacheDecoder<'a, 'tcx> {
601 fn specialized_decode(&mut self) -> Result<Span, Self::Error> {
602 let tag: u8 = Decodable::decode(self)?;
604 if tag == TAG_INVALID_SPAN {
607 debug_assert_eq!(tag, TAG_VALID_SPAN);
610 let file_lo_index = SourceFileIndex::decode(self)?;
611 let line_lo = usize::decode(self)?;
612 let col_lo = BytePos::decode(self)?;
613 let len = BytePos::decode(self)?;
615 let file_lo = self.file_index_to_file(file_lo_index);
616 let lo = file_lo.lines[line_lo - 1] + col_lo;
619 let expn_info_tag = u8::decode(self)?;
621 let ctxt = match expn_info_tag {
622 TAG_NO_EXPANSION_INFO => {
623 SyntaxContext::empty()
625 TAG_EXPANSION_INFO_INLINE => {
626 let pos = AbsoluteBytePos::new(self.opaque.position());
627 let expn_info: ExpnInfo = Decodable::decode(self)?;
628 let ctxt = SyntaxContext::allocate_directly(expn_info);
629 self.synthetic_expansion_infos.borrow_mut().insert(pos, ctxt);
632 TAG_EXPANSION_INFO_SHORTHAND => {
633 let pos = AbsoluteBytePos::decode(self)?;
634 let cached_ctxt = self.synthetic_expansion_infos
639 if let Some(ctxt) = cached_ctxt {
642 let expn_info = self.with_position(pos.to_usize(), |this| {
643 ExpnInfo::decode(this)
645 let ctxt = SyntaxContext::allocate_directly(expn_info);
646 self.synthetic_expansion_infos.borrow_mut().insert(pos, ctxt);
655 Ok(Span::new(lo, hi, ctxt))
659 // This impl makes sure that we get a runtime error when we try decode a
660 // DefIndex that is not contained in a DefId. Such a case would be problematic
661 // because we would not know how to transform the DefIndex to the current
663 impl<'a, 'tcx> SpecializedDecoder<DefIndex> for CacheDecoder<'a, 'tcx> {
664 fn specialized_decode(&mut self) -> Result<DefIndex, Self::Error> {
665 bug!("Trying to decode DefIndex outside the context of a DefId")
669 // Both the CrateNum and the DefIndex of a DefId can change in between two
670 // compilation sessions. We use the DefPathHash, which is stable across
671 // sessions, to map the old DefId to the new one.
672 impl<'a, 'tcx> SpecializedDecoder<DefId> for CacheDecoder<'a, 'tcx> {
674 fn specialized_decode(&mut self) -> Result<DefId, Self::Error> {
675 // Load the DefPathHash which is was we encoded the DefId as.
676 let def_path_hash = DefPathHash::decode(self)?;
678 // Using the DefPathHash, we can lookup the new DefId
679 Ok(self.tcx().def_path_hash_to_def_id.as_ref().unwrap()[&def_path_hash])
683 impl<'a, 'tcx> SpecializedDecoder<LocalDefId> for CacheDecoder<'a, 'tcx> {
685 fn specialized_decode(&mut self) -> Result<LocalDefId, Self::Error> {
686 Ok(LocalDefId::from_def_id(DefId::decode(self)?))
690 impl<'a, 'tcx> SpecializedDecoder<hir::HirId> for CacheDecoder<'a, 'tcx> {
691 fn specialized_decode(&mut self) -> Result<hir::HirId, Self::Error> {
692 // Load the DefPathHash which is was we encoded the DefIndex as.
693 let def_path_hash = DefPathHash::decode(self)?;
695 // Use the DefPathHash to map to the current DefId.
696 let def_id = self.tcx()
697 .def_path_hash_to_def_id
699 .unwrap()[&def_path_hash];
701 debug_assert!(def_id.is_local());
703 // The ItemLocalId needs no remapping.
704 let local_id = hir::ItemLocalId::decode(self)?;
706 // Reconstruct the HirId and look up the corresponding NodeId in the
707 // context of the current session.
715 // NodeIds are not stable across compilation sessions, so we store them in their
716 // HirId representation. This allows use to map them to the current NodeId.
717 impl<'a, 'tcx> SpecializedDecoder<NodeId> for CacheDecoder<'a, 'tcx> {
719 fn specialized_decode(&mut self) -> Result<NodeId, Self::Error> {
720 let hir_id = hir::HirId::decode(self)?;
721 Ok(self.tcx().hir().hir_to_node_id(hir_id))
725 impl<'a, 'tcx> SpecializedDecoder<Fingerprint> for CacheDecoder<'a, 'tcx> {
726 fn specialized_decode(&mut self) -> Result<Fingerprint, Self::Error> {
727 Fingerprint::decode_opaque(&mut self.opaque)
731 impl<'a, 'tcx, T: Decodable> SpecializedDecoder<mir::ClearCrossCrate<T>>
732 for CacheDecoder<'a, 'tcx>
735 fn specialized_decode(&mut self) -> Result<mir::ClearCrossCrate<T>, Self::Error> {
736 let discr = u8::decode(self)?;
739 TAG_CLEAR_CROSS_CRATE_CLEAR => Ok(mir::ClearCrossCrate::Clear),
740 TAG_CLEAR_CROSS_CRATE_SET => {
741 let val = T::decode(self)?;
742 Ok(mir::ClearCrossCrate::Set(val))
751 //- ENCODING -------------------------------------------------------------------
753 struct CacheEncoder<'a, 'tcx, E: ty_codec::TyEncoder> {
754 tcx: TyCtxt<'tcx, 'tcx>,
756 type_shorthands: FxHashMap<Ty<'tcx>, usize>,
757 predicate_shorthands: FxHashMap<ty::Predicate<'tcx>, usize>,
758 expn_info_shorthands: FxHashMap<Mark, AbsoluteBytePos>,
759 interpret_allocs: FxHashMap<interpret::AllocId, usize>,
760 interpret_allocs_inverse: Vec<interpret::AllocId>,
761 source_map: CachingSourceMapView<'tcx>,
762 file_to_file_index: FxHashMap<*const SourceFile, SourceFileIndex>,
765 impl<'a, 'tcx, E> CacheEncoder<'a, 'tcx, E>
767 E: 'a + ty_codec::TyEncoder,
769 fn source_file_index(&mut self, source_file: Lrc<SourceFile>) -> SourceFileIndex {
770 self.file_to_file_index[&(&*source_file as *const SourceFile)]
773 /// Encode something with additional information that allows to do some
774 /// sanity checks when decoding the data again. This method will first
775 /// encode the specified tag, then the given value, then the number of
776 /// bytes taken up by tag and value. On decoding, we can then verify that
777 /// we get the expected tag and read the expected number of bytes.
778 fn encode_tagged<T: Encodable, V: Encodable>(&mut self,
781 -> Result<(), E::Error>
783 let start_pos = self.position();
788 let end_pos = self.position();
789 ((end_pos - start_pos) as u64).encode(self)
793 impl<'a, 'tcx, E> SpecializedEncoder<interpret::AllocId> for CacheEncoder<'a, 'tcx, E>
795 E: 'a + ty_codec::TyEncoder,
797 fn specialized_encode(&mut self, alloc_id: &interpret::AllocId) -> Result<(), Self::Error> {
798 use std::collections::hash_map::Entry;
799 let index = match self.interpret_allocs.entry(*alloc_id) {
800 Entry::Occupied(e) => *e.get(),
801 Entry::Vacant(e) => {
802 let idx = self.interpret_allocs_inverse.len();
803 self.interpret_allocs_inverse.push(*alloc_id);
813 impl<'a, 'tcx, E> SpecializedEncoder<Span> for CacheEncoder<'a, 'tcx, E>
815 E: 'a + ty_codec::TyEncoder,
817 fn specialized_encode(&mut self, span: &Span) -> Result<(), Self::Error> {
819 if *span == DUMMY_SP {
820 return TAG_INVALID_SPAN.encode(self);
823 let span_data = span.data();
825 if span_data.hi < span_data.lo {
826 return TAG_INVALID_SPAN.encode(self);
829 let (file_lo, line_lo, col_lo) = match self.source_map
830 .byte_pos_to_line_and_col(span_data.lo) {
832 None => return TAG_INVALID_SPAN.encode(self)
835 if !file_lo.contains(span_data.hi) {
836 return TAG_INVALID_SPAN.encode(self);
839 let len = span_data.hi - span_data.lo;
841 let source_file_index = self.source_file_index(file_lo);
843 TAG_VALID_SPAN.encode(self)?;
844 source_file_index.encode(self)?;
845 line_lo.encode(self)?;
846 col_lo.encode(self)?;
849 if span_data.ctxt == SyntaxContext::empty() {
850 TAG_NO_EXPANSION_INFO.encode(self)
852 let (mark, expn_info) = span_data.ctxt.outer_and_expn_info();
853 if let Some(expn_info) = expn_info {
854 if let Some(pos) = self.expn_info_shorthands.get(&mark).cloned() {
855 TAG_EXPANSION_INFO_SHORTHAND.encode(self)?;
858 TAG_EXPANSION_INFO_INLINE.encode(self)?;
859 let pos = AbsoluteBytePos::new(self.position());
860 self.expn_info_shorthands.insert(mark, pos);
861 expn_info.encode(self)
864 TAG_NO_EXPANSION_INFO.encode(self)
870 impl<'a, 'tcx, E> ty_codec::TyEncoder for CacheEncoder<'a, 'tcx, E>
872 E: 'a + ty_codec::TyEncoder,
875 fn position(&self) -> usize {
876 self.encoder.position()
880 impl<'a, 'tcx, E> SpecializedEncoder<CrateNum> for CacheEncoder<'a, 'tcx, E>
882 E: 'a + ty_codec::TyEncoder,
885 fn specialized_encode(&mut self, cnum: &CrateNum) -> Result<(), Self::Error> {
886 self.emit_u32(cnum.as_u32())
890 impl<'a, 'tcx, E> SpecializedEncoder<Ty<'tcx>> for CacheEncoder<'a, 'tcx, E>
892 E: 'a + ty_codec::TyEncoder,
895 fn specialized_encode(&mut self, ty: &Ty<'tcx>) -> Result<(), Self::Error> {
896 ty_codec::encode_with_shorthand(self, ty,
897 |encoder| &mut encoder.type_shorthands)
901 impl<'a, 'tcx, E> SpecializedEncoder<ty::GenericPredicates<'tcx>> for CacheEncoder<'a, 'tcx, E>
903 E: 'a + ty_codec::TyEncoder,
906 fn specialized_encode(&mut self,
907 predicates: &ty::GenericPredicates<'tcx>)
908 -> Result<(), Self::Error> {
909 ty_codec::encode_predicates(self, predicates,
910 |encoder| &mut encoder.predicate_shorthands)
914 impl<'a, 'tcx, E> SpecializedEncoder<hir::HirId> for CacheEncoder<'a, 'tcx, E>
916 E: 'a + ty_codec::TyEncoder,
919 fn specialized_encode(&mut self, id: &hir::HirId) -> Result<(), Self::Error> {
925 let def_path_hash = self.tcx.hir().definitions().def_path_hash(owner);
927 def_path_hash.encode(self)?;
928 local_id.encode(self)
932 impl<'a, 'tcx, E> SpecializedEncoder<DefId> for CacheEncoder<'a, 'tcx, E>
934 E: 'a + ty_codec::TyEncoder,
937 fn specialized_encode(&mut self, id: &DefId) -> Result<(), Self::Error> {
938 let def_path_hash = self.tcx.def_path_hash(*id);
939 def_path_hash.encode(self)
943 impl<'a, 'tcx, E> SpecializedEncoder<LocalDefId> for CacheEncoder<'a, 'tcx, E>
945 E: 'a + ty_codec::TyEncoder,
948 fn specialized_encode(&mut self, id: &LocalDefId) -> Result<(), Self::Error> {
949 id.to_def_id().encode(self)
953 impl<'a, 'tcx, E> SpecializedEncoder<DefIndex> for CacheEncoder<'a, 'tcx, E>
955 E: 'a + ty_codec::TyEncoder,
957 fn specialized_encode(&mut self, _: &DefIndex) -> Result<(), Self::Error> {
958 bug!("Encoding DefIndex without context.")
962 // NodeIds are not stable across compilation sessions, so we store them in their
963 // HirId representation. This allows use to map them to the current NodeId.
964 impl<'a, 'tcx, E> SpecializedEncoder<NodeId> for CacheEncoder<'a, 'tcx, E>
966 E: 'a + ty_codec::TyEncoder,
969 fn specialized_encode(&mut self, node_id: &NodeId) -> Result<(), Self::Error> {
970 let hir_id = self.tcx.hir().node_to_hir_id(*node_id);
975 impl<'a, 'tcx> SpecializedEncoder<Fingerprint> for CacheEncoder<'a, 'tcx, opaque::Encoder> {
976 fn specialized_encode(&mut self, f: &Fingerprint) -> Result<(), Self::Error> {
977 f.encode_opaque(&mut self.encoder)
981 impl<'a, 'tcx, E, T> SpecializedEncoder<mir::ClearCrossCrate<T>> for CacheEncoder<'a, 'tcx, E>
983 E: 'a + ty_codec::TyEncoder,
987 fn specialized_encode(&mut self,
988 val: &mir::ClearCrossCrate<T>)
989 -> Result<(), Self::Error> {
991 mir::ClearCrossCrate::Clear => {
992 TAG_CLEAR_CROSS_CRATE_CLEAR.encode(self)
994 mir::ClearCrossCrate::Set(ref val) => {
995 TAG_CLEAR_CROSS_CRATE_SET.encode(self)?;
1002 macro_rules! encoder_methods {
1003 ($($name:ident($ty:ty);)*) => {
1004 $(fn $name(&mut self, value: $ty) -> Result<(), Self::Error> {
1005 self.encoder.$name(value)
1010 impl<'a, 'tcx, E> Encoder for CacheEncoder<'a, 'tcx, E>
1012 E: 'a + ty_codec::TyEncoder,
1014 type Error = E::Error;
1016 fn emit_unit(&mut self) -> Result<(), Self::Error> {
1043 // An integer that will always encode to 8 bytes.
1044 struct IntEncodedWithFixedSize(u64);
1046 impl IntEncodedWithFixedSize {
1047 pub const ENCODED_SIZE: usize = 8;
1050 impl UseSpecializedEncodable for IntEncodedWithFixedSize {}
1051 impl UseSpecializedDecodable for IntEncodedWithFixedSize {}
1053 impl SpecializedEncoder<IntEncodedWithFixedSize> for opaque::Encoder {
1054 fn specialized_encode(&mut self, x: &IntEncodedWithFixedSize) -> Result<(), Self::Error> {
1055 let start_pos = self.position();
1056 for i in 0 .. IntEncodedWithFixedSize::ENCODED_SIZE {
1057 ((x.0 >> i * 8) as u8).encode(self)?;
1059 let end_pos = self.position();
1060 assert_eq!((end_pos - start_pos), IntEncodedWithFixedSize::ENCODED_SIZE);
1065 impl<'a> SpecializedDecoder<IntEncodedWithFixedSize> for opaque::Decoder<'a> {
1066 fn specialized_decode(&mut self) -> Result<IntEncodedWithFixedSize, Self::Error> {
1067 let mut value: u64 = 0;
1068 let start_pos = self.position();
1070 for i in 0 .. IntEncodedWithFixedSize::ENCODED_SIZE {
1071 let byte: u8 = Decodable::decode(self)?;
1072 value |= (byte as u64) << (i * 8);
1075 let end_pos = self.position();
1076 assert_eq!((end_pos - start_pos), IntEncodedWithFixedSize::ENCODED_SIZE);
1078 Ok(IntEncodedWithFixedSize(value))
1082 fn encode_query_results<'a, 'tcx, Q, E>(
1083 tcx: TyCtxt<'tcx, 'tcx>,
1084 encoder: &mut CacheEncoder<'a, 'tcx, E>,
1085 query_result_index: &mut EncodedQueryResultIndex,
1086 ) -> Result<(), E::Error>
1088 Q: super::config::QueryDescription<'tcx>,
1090 Q::Value: Encodable,
1092 let desc = &format!("encode_query_results for {}",
1093 unsafe { ::std::intrinsics::type_name::<Q>() });
1095 time_ext(tcx.sess.time_extended(), Some(tcx.sess), desc, || {
1096 let map = Q::query_cache(tcx).borrow();
1097 assert!(map.active.is_empty());
1098 for (key, entry) in map.results.iter() {
1099 if Q::cache_on_disk(tcx, key.clone()) {
1100 let dep_node = SerializedDepNodeIndex::new(entry.index.index());
1102 // Record position of the cache entry
1103 query_result_index.push((dep_node, AbsoluteBytePos::new(encoder.position())));
1105 // Encode the type check tables with the SerializedDepNodeIndex
1107 encoder.encode_tagged(dep_node, &entry.value)?;