1 // Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
15 use rustc::middle::cstore::{LinkMeta, LinkagePreference, NativeLibrary,
16 EncodedMetadata, EncodedMetadataHash};
17 use rustc::hir::def_id::{CrateNum, CRATE_DEF_INDEX, DefIndex, DefId, LOCAL_CRATE};
18 use rustc::hir::map::definitions::DefPathTable;
19 use rustc::middle::dependency_format::Linkage;
20 use rustc::middle::lang_items;
22 use rustc::traits::specialization_graph;
23 use rustc::ty::{self, Ty, TyCtxt, ReprOptions};
25 use rustc::session::config::{self, CrateTypeProcMacro};
26 use rustc::util::nodemap::{FxHashMap, NodeSet};
28 use rustc_serialize::{Encodable, Encoder, SpecializedEncoder, opaque};
31 use std::io::prelude::*;
35 use syntax::ast::{self, CRATE_NODE_ID};
36 use syntax::codemap::Spanned;
38 use syntax::symbol::Symbol;
41 use rustc::hir::{self, PatKind};
42 use rustc::hir::itemlikevisit::ItemLikeVisitor;
43 use rustc::hir::intravisit::{Visitor, NestedVisitorMap};
44 use rustc::hir::intravisit;
46 use super::index_builder::{FromId, IndexBuilder, Untracked, EntryBuilder};
48 pub struct EncodeContext<'a, 'tcx: 'a> {
49 opaque: opaque::Encoder<'a>,
50 pub tcx: TyCtxt<'a, 'tcx, 'tcx>,
51 link_meta: &'a LinkMeta,
52 cstore: &'a cstore::CStore,
53 exported_symbols: &'a NodeSet,
55 lazy_state: LazyState,
56 type_shorthands: FxHashMap<Ty<'tcx>, usize>,
57 predicate_shorthands: FxHashMap<ty::Predicate<'tcx>, usize>,
59 pub metadata_hashes: Vec<EncodedMetadataHash>,
62 macro_rules! encoder_methods {
63 ($($name:ident($ty:ty);)*) => {
64 $(fn $name(&mut self, value: $ty) -> Result<(), Self::Error> {
65 self.opaque.$name(value)
70 impl<'a, 'tcx> Encoder for EncodeContext<'a, 'tcx> {
71 type Error = <opaque::Encoder<'a> as Encoder>::Error;
73 fn emit_nil(&mut self) -> Result<(), Self::Error> {
100 impl<'a, 'tcx, T> SpecializedEncoder<Lazy<T>> for EncodeContext<'a, 'tcx> {
101 fn specialized_encode(&mut self, lazy: &Lazy<T>) -> Result<(), Self::Error> {
102 self.emit_lazy_distance(lazy.position, Lazy::<T>::min_size())
106 impl<'a, 'tcx, T> SpecializedEncoder<LazySeq<T>> for EncodeContext<'a, 'tcx> {
107 fn specialized_encode(&mut self, seq: &LazySeq<T>) -> Result<(), Self::Error> {
108 self.emit_usize(seq.len)?;
112 self.emit_lazy_distance(seq.position, LazySeq::<T>::min_size(seq.len))
116 impl<'a, 'tcx> SpecializedEncoder<Ty<'tcx>> for EncodeContext<'a, 'tcx> {
117 fn specialized_encode(&mut self, ty: &Ty<'tcx>) -> Result<(), Self::Error> {
118 self.encode_with_shorthand(ty, &ty.sty, |ecx| &mut ecx.type_shorthands)
122 impl<'a, 'tcx> SpecializedEncoder<ty::GenericPredicates<'tcx>> for EncodeContext<'a, 'tcx> {
123 fn specialized_encode(&mut self,
124 predicates: &ty::GenericPredicates<'tcx>)
125 -> Result<(), Self::Error> {
126 predicates.parent.encode(self)?;
127 predicates.predicates.len().encode(self)?;
128 for predicate in &predicates.predicates {
129 self.encode_with_shorthand(predicate, predicate, |ecx| &mut ecx.predicate_shorthands)?
135 impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
136 pub fn position(&self) -> usize {
137 self.opaque.position()
140 fn emit_node<F: FnOnce(&mut Self, usize) -> R, R>(&mut self, f: F) -> R {
141 assert_eq!(self.lazy_state, LazyState::NoNode);
142 let pos = self.position();
143 self.lazy_state = LazyState::NodeStart(pos);
144 let r = f(self, pos);
145 self.lazy_state = LazyState::NoNode;
149 fn emit_lazy_distance(&mut self,
152 -> Result<(), <Self as Encoder>::Error> {
153 let min_end = position + min_size;
154 let distance = match self.lazy_state {
155 LazyState::NoNode => bug!("emit_lazy_distance: outside of a metadata node"),
156 LazyState::NodeStart(start) => {
157 assert!(min_end <= start);
160 LazyState::Previous(last_min_end) => {
161 assert!(last_min_end <= position);
162 position - last_min_end
165 self.lazy_state = LazyState::Previous(min_end);
166 self.emit_usize(distance)
169 pub fn lazy<T: Encodable>(&mut self, value: &T) -> Lazy<T> {
170 self.emit_node(|ecx, pos| {
171 value.encode(ecx).unwrap();
173 assert!(pos + Lazy::<T>::min_size() <= ecx.position());
174 Lazy::with_position(pos)
178 pub fn lazy_seq<I, T>(&mut self, iter: I) -> LazySeq<T>
179 where I: IntoIterator<Item = T>,
182 self.emit_node(|ecx, pos| {
183 let len = iter.into_iter().map(|value| value.encode(ecx).unwrap()).count();
185 assert!(pos + LazySeq::<T>::min_size(len) <= ecx.position());
186 LazySeq::with_position_and_length(pos, len)
190 pub fn lazy_seq_ref<'b, I, T>(&mut self, iter: I) -> LazySeq<T>
191 where I: IntoIterator<Item = &'b T>,
194 self.emit_node(|ecx, pos| {
195 let len = iter.into_iter().map(|value| value.encode(ecx).unwrap()).count();
197 assert!(pos + LazySeq::<T>::min_size(len) <= ecx.position());
198 LazySeq::with_position_and_length(pos, len)
202 /// Encode the given value or a previously cached shorthand.
203 fn encode_with_shorthand<T, U, M>(&mut self,
207 -> Result<(), <Self as Encoder>::Error>
208 where M: for<'b> Fn(&'b mut Self) -> &'b mut FxHashMap<T, usize>,
209 T: Clone + Eq + Hash,
212 let existing_shorthand = map(self).get(value).cloned();
213 if let Some(shorthand) = existing_shorthand {
214 return self.emit_usize(shorthand);
217 let start = self.position();
218 variant.encode(self)?;
219 let len = self.position() - start;
221 // The shorthand encoding uses the same usize as the
222 // discriminant, with an offset so they can't conflict.
223 let discriminant = unsafe { intrinsics::discriminant_value(variant) };
224 assert!(discriminant < SHORTHAND_OFFSET as u64);
225 let shorthand = start + SHORTHAND_OFFSET;
227 // Get the number of bits that leb128 could fit
228 // in the same space as the fully encoded type.
229 let leb128_bits = len * 7;
231 // Check that the shorthand is a not longer than the
232 // full encoding itself, i.e. it's an obvious win.
233 if leb128_bits >= 64 || (shorthand as u64) < (1 << leb128_bits) {
234 map(self).insert(value.clone(), shorthand);
241 impl<'a, 'b: 'a, 'tcx: 'b> EntryBuilder<'a, 'b, 'tcx> {
242 fn encode_item_variances(&mut self, def_id: DefId) -> LazySeq<ty::Variance> {
243 debug!("EntryBuilder::encode_item_variances({:?})", def_id);
245 self.lazy_seq_from_slice(&tcx.variances_of(def_id))
248 fn encode_item_type(&mut self, def_id: DefId) -> Lazy<Ty<'tcx>> {
250 let ty = tcx.type_of(def_id);
251 debug!("EntryBuilder::encode_item_type({:?}) => {:?}", def_id, ty);
255 /// Encode data for the given variant of the given ADT. The
256 /// index of the variant is untracked: this is ok because we
257 /// will have to lookup the adt-def by its id, and that gives us
258 /// the right to access any information in the adt-def (including,
259 /// e.g., the length of the various vectors).
260 fn encode_enum_variant_info(&mut self,
261 (enum_did, Untracked(index)): (DefId, Untracked<usize>))
264 let def = tcx.adt_def(enum_did);
265 let variant = &def.variants[index];
266 let def_id = variant.did;
267 debug!("EntryBuilder::encode_enum_variant_info({:?})", def_id);
269 let data = VariantData {
270 ctor_kind: variant.ctor_kind,
271 discr: variant.discr,
275 let enum_id = tcx.hir.as_local_node_id(enum_did).unwrap();
276 let enum_vis = &tcx.hir.expect_item(enum_id).vis;
279 kind: EntryKind::Variant(self.lazy(&data)),
280 visibility: self.lazy(&ty::Visibility::from_hir(enum_vis, enum_id, tcx)),
281 span: self.lazy(&tcx.def_span(def_id)),
282 attributes: self.encode_attributes(&tcx.get_attrs(def_id)),
283 children: self.lazy_seq(variant.fields.iter().map(|f| {
284 assert!(f.did.is_local());
287 stability: self.encode_stability(def_id),
288 deprecation: self.encode_deprecation(def_id),
290 ty: Some(self.encode_item_type(def_id)),
291 inherent_impls: LazySeq::empty(),
292 variances: LazySeq::empty(),
293 generics: Some(self.encode_generics(def_id)),
294 predicates: Some(self.encode_predicates(def_id)),
297 mir: self.encode_mir(def_id),
301 fn encode_info_for_mod(&mut self,
302 FromId(id, (md, attrs, vis)): FromId<(&hir::Mod,
307 let def_id = tcx.hir.local_def_id(id);
308 debug!("EntryBuilder::encode_info_for_mod({:?})", def_id);
311 reexports: match tcx.export_map.get(&id) {
312 Some(exports) if *vis == hir::Public => {
313 self.lazy_seq_from_slice(exports.as_slice())
315 _ => LazySeq::empty(),
320 kind: EntryKind::Mod(self.lazy(&data)),
321 visibility: self.lazy(&ty::Visibility::from_hir(vis, id, tcx)),
322 span: self.lazy(&md.inner),
323 attributes: self.encode_attributes(attrs),
324 children: self.lazy_seq(md.item_ids.iter().map(|item_id| {
325 tcx.hir.local_def_id(item_id.id).index
327 stability: self.encode_stability(def_id),
328 deprecation: self.encode_deprecation(def_id),
331 inherent_impls: LazySeq::empty(),
332 variances: LazySeq::empty(),
342 impl<'a, 'b, 'tcx> IndexBuilder<'a, 'b, 'tcx> {
343 fn encode_fields(&mut self, adt_def_id: DefId) {
344 let def = self.tcx.adt_def(adt_def_id);
345 for (variant_index, variant) in def.variants.iter().enumerate() {
346 for (field_index, field) in variant.fields.iter().enumerate() {
347 self.record(field.did,
348 EntryBuilder::encode_field,
349 (adt_def_id, Untracked((variant_index, field_index))));
355 impl<'a, 'b: 'a, 'tcx: 'b> EntryBuilder<'a, 'b, 'tcx> {
356 /// Encode data for the given field of the given variant of the
357 /// given ADT. The indices of the variant/field are untracked:
358 /// this is ok because we will have to lookup the adt-def by its
359 /// id, and that gives us the right to access any information in
360 /// the adt-def (including, e.g., the length of the various
362 fn encode_field(&mut self,
363 (adt_def_id, Untracked((variant_index, field_index))): (DefId,
368 let variant = &tcx.adt_def(adt_def_id).variants[variant_index];
369 let field = &variant.fields[field_index];
371 let def_id = field.did;
372 debug!("EntryBuilder::encode_field({:?})", def_id);
374 let variant_id = tcx.hir.as_local_node_id(variant.did).unwrap();
375 let variant_data = tcx.hir.expect_variant_data(variant_id);
378 kind: EntryKind::Field,
379 visibility: self.lazy(&field.vis),
380 span: self.lazy(&tcx.def_span(def_id)),
381 attributes: self.encode_attributes(&variant_data.fields()[field_index].attrs),
382 children: LazySeq::empty(),
383 stability: self.encode_stability(def_id),
384 deprecation: self.encode_deprecation(def_id),
386 ty: Some(self.encode_item_type(def_id)),
387 inherent_impls: LazySeq::empty(),
388 variances: LazySeq::empty(),
389 generics: Some(self.encode_generics(def_id)),
390 predicates: Some(self.encode_predicates(def_id)),
397 fn encode_struct_ctor(&mut self, (adt_def_id, def_id): (DefId, DefId)) -> Entry<'tcx> {
398 debug!("EntryBuilder::encode_struct_ctor({:?})", def_id);
400 let variant = tcx.adt_def(adt_def_id).struct_variant();
402 let data = VariantData {
403 ctor_kind: variant.ctor_kind,
404 discr: variant.discr,
405 struct_ctor: Some(def_id.index),
408 let struct_id = tcx.hir.as_local_node_id(adt_def_id).unwrap();
409 let struct_vis = &tcx.hir.expect_item(struct_id).vis;
410 let mut ctor_vis = ty::Visibility::from_hir(struct_vis, struct_id, tcx);
411 for field in &variant.fields {
412 if ctor_vis.is_at_least(field.vis, tcx) {
413 ctor_vis = field.vis;
417 let repr_options = get_repr_options(&tcx, adt_def_id);
420 kind: EntryKind::Struct(self.lazy(&data), repr_options),
421 visibility: self.lazy(&ctor_vis),
422 span: self.lazy(&tcx.def_span(def_id)),
423 attributes: LazySeq::empty(),
424 children: LazySeq::empty(),
425 stability: self.encode_stability(def_id),
426 deprecation: self.encode_deprecation(def_id),
428 ty: Some(self.encode_item_type(def_id)),
429 inherent_impls: LazySeq::empty(),
430 variances: LazySeq::empty(),
431 generics: Some(self.encode_generics(def_id)),
432 predicates: Some(self.encode_predicates(def_id)),
435 mir: self.encode_mir(def_id),
439 fn encode_generics(&mut self, def_id: DefId) -> Lazy<ty::Generics> {
440 debug!("EntryBuilder::encode_generics({:?})", def_id);
442 self.lazy(tcx.generics_of(def_id))
445 fn encode_predicates(&mut self, def_id: DefId) -> Lazy<ty::GenericPredicates<'tcx>> {
446 debug!("EntryBuilder::encode_predicates({:?})", def_id);
448 self.lazy(&tcx.predicates_of(def_id))
451 fn encode_info_for_trait_item(&mut self, def_id: DefId) -> Entry<'tcx> {
452 debug!("EntryBuilder::encode_info_for_trait_item({:?})", def_id);
455 let node_id = tcx.hir.as_local_node_id(def_id).unwrap();
456 let ast_item = tcx.hir.expect_trait_item(node_id);
457 let trait_item = tcx.associated_item(def_id);
459 let container = match trait_item.defaultness {
460 hir::Defaultness::Default { has_value: true } =>
461 AssociatedContainer::TraitWithDefault,
462 hir::Defaultness::Default { has_value: false } =>
463 AssociatedContainer::TraitRequired,
464 hir::Defaultness::Final =>
465 span_bug!(ast_item.span, "traits cannot have final items"),
468 let kind = match trait_item.kind {
469 ty::AssociatedKind::Const => {
470 EntryKind::AssociatedConst(container, 0)
472 ty::AssociatedKind::Method => {
473 let fn_data = if let hir::TraitItemKind::Method(_, ref m) = ast_item.node {
474 let arg_names = match *m {
475 hir::TraitMethod::Required(ref names) => {
476 self.encode_fn_arg_names(names)
478 hir::TraitMethod::Provided(body) => {
479 self.encode_fn_arg_names_for_body(body)
483 constness: hir::Constness::NotConst,
489 EntryKind::Method(self.lazy(&MethodData {
491 container: container,
492 has_self: trait_item.method_has_self_argument,
495 ty::AssociatedKind::Type => EntryKind::AssociatedType(container),
500 visibility: self.lazy(&trait_item.vis),
501 span: self.lazy(&ast_item.span),
502 attributes: self.encode_attributes(&ast_item.attrs),
503 children: LazySeq::empty(),
504 stability: self.encode_stability(def_id),
505 deprecation: self.encode_deprecation(def_id),
507 ty: match trait_item.kind {
508 ty::AssociatedKind::Const |
509 ty::AssociatedKind::Method => {
510 Some(self.encode_item_type(def_id))
512 ty::AssociatedKind::Type => {
513 if trait_item.defaultness.has_value() {
514 Some(self.encode_item_type(def_id))
520 inherent_impls: LazySeq::empty(),
521 variances: LazySeq::empty(),
522 generics: Some(self.encode_generics(def_id)),
523 predicates: Some(self.encode_predicates(def_id)),
525 ast: if let hir::TraitItemKind::Const(_, Some(body)) = ast_item.node {
526 Some(self.encode_body(body))
530 mir: self.encode_mir(def_id),
534 fn encode_info_for_impl_item(&mut self, def_id: DefId) -> Entry<'tcx> {
535 debug!("EntryBuilder::encode_info_for_impl_item({:?})", def_id);
536 let node_id = self.tcx.hir.as_local_node_id(def_id).unwrap();
537 let ast_item = self.tcx.hir.expect_impl_item(node_id);
538 let impl_item = self.tcx.associated_item(def_id);
540 let container = match impl_item.defaultness {
541 hir::Defaultness::Default { has_value: true } => AssociatedContainer::ImplDefault,
542 hir::Defaultness::Final => AssociatedContainer::ImplFinal,
543 hir::Defaultness::Default { has_value: false } =>
544 span_bug!(ast_item.span, "impl items always have values (currently)"),
547 let kind = match impl_item.kind {
548 ty::AssociatedKind::Const => {
549 EntryKind::AssociatedConst(container,
550 self.tcx.at(ast_item.span).mir_const_qualif(def_id))
552 ty::AssociatedKind::Method => {
553 let fn_data = if let hir::ImplItemKind::Method(ref sig, body) = ast_item.node {
555 constness: sig.constness,
556 arg_names: self.encode_fn_arg_names_for_body(body),
561 EntryKind::Method(self.lazy(&MethodData {
563 container: container,
564 has_self: impl_item.method_has_self_argument,
567 ty::AssociatedKind::Type => EntryKind::AssociatedType(container)
570 let (ast, mir) = if let hir::ImplItemKind::Const(_, body) = ast_item.node {
572 } else if let hir::ImplItemKind::Method(ref sig, body) = ast_item.node {
573 let generics = self.tcx.generics_of(def_id);
574 let types = generics.parent_types as usize + generics.types.len();
575 let needs_inline = types > 0 || attr::requests_inline(&ast_item.attrs);
576 let is_const_fn = sig.constness == hir::Constness::Const;
577 let ast = if is_const_fn { Some(body) } else { None };
578 let always_encode_mir = self.tcx.sess.opts.debugging_opts.always_encode_mir;
579 (ast, needs_inline || is_const_fn || always_encode_mir)
586 visibility: self.lazy(&impl_item.vis),
587 span: self.lazy(&ast_item.span),
588 attributes: self.encode_attributes(&ast_item.attrs),
589 children: LazySeq::empty(),
590 stability: self.encode_stability(def_id),
591 deprecation: self.encode_deprecation(def_id),
593 ty: Some(self.encode_item_type(def_id)),
594 inherent_impls: LazySeq::empty(),
595 variances: LazySeq::empty(),
596 generics: Some(self.encode_generics(def_id)),
597 predicates: Some(self.encode_predicates(def_id)),
599 ast: ast.map(|body| self.encode_body(body)),
600 mir: if mir { self.encode_mir(def_id) } else { None },
604 fn encode_fn_arg_names_for_body(&mut self, body_id: hir::BodyId)
605 -> LazySeq<ast::Name> {
606 let _ignore = self.tcx.dep_graph.in_ignore();
607 let body = self.tcx.hir.body(body_id);
608 self.lazy_seq(body.arguments.iter().map(|arg| {
610 PatKind::Binding(_, _, name, _) => name.node,
611 _ => Symbol::intern("")
616 fn encode_fn_arg_names(&mut self, names: &[Spanned<ast::Name>])
617 -> LazySeq<ast::Name> {
618 self.lazy_seq(names.iter().map(|name| name.node))
621 fn encode_mir(&mut self, def_id: DefId) -> Option<Lazy<mir::Mir<'tcx>>> {
622 debug!("EntryBuilder::encode_mir({:?})", def_id);
623 self.tcx.maps.mir.borrow().get(&def_id).map(|mir| self.lazy(&*mir.borrow()))
626 // Encodes the inherent implementations of a structure, enumeration, or trait.
627 fn encode_inherent_implementations(&mut self, def_id: DefId) -> LazySeq<DefIndex> {
628 debug!("EntryBuilder::encode_inherent_implementations({:?})", def_id);
629 match self.tcx.maps.inherent_impls.borrow().get(&def_id) {
630 None => LazySeq::empty(),
631 Some(implementations) => {
632 self.lazy_seq(implementations.iter().map(|&def_id| {
633 assert!(def_id.is_local());
640 fn encode_stability(&mut self, def_id: DefId) -> Option<Lazy<attr::Stability>> {
641 debug!("EntryBuilder::encode_stability({:?})", def_id);
642 self.tcx.lookup_stability(def_id).map(|stab| self.lazy(stab))
645 fn encode_deprecation(&mut self, def_id: DefId) -> Option<Lazy<attr::Deprecation>> {
646 debug!("EntryBuilder::encode_deprecation({:?})", def_id);
647 self.tcx.lookup_deprecation(def_id).map(|depr| self.lazy(&depr))
650 fn encode_info_for_item(&mut self, (def_id, item): (DefId, &'tcx hir::Item)) -> Entry<'tcx> {
653 debug!("EntryBuilder::encode_info_for_item({:?})", def_id);
655 let kind = match item.node {
656 hir::ItemStatic(_, hir::MutMutable, _) => EntryKind::MutStatic,
657 hir::ItemStatic(_, hir::MutImmutable, _) => EntryKind::ImmStatic,
658 hir::ItemConst(..) => {
659 EntryKind::Const(tcx.at(item.span).mir_const_qualif(def_id))
661 hir::ItemFn(_, _, constness, .., body) => {
663 constness: constness,
664 arg_names: self.encode_fn_arg_names_for_body(body),
667 EntryKind::Fn(self.lazy(&data))
669 hir::ItemMod(ref m) => {
670 return self.encode_info_for_mod(FromId(item.id, (m, &item.attrs, &item.vis)));
672 hir::ItemForeignMod(_) => EntryKind::ForeignMod,
673 hir::ItemGlobalAsm(..) => EntryKind::GlobalAsm,
674 hir::ItemTy(..) => EntryKind::Type,
675 hir::ItemEnum(..) => EntryKind::Enum(get_repr_options(&tcx, def_id)),
676 hir::ItemStruct(ref struct_def, _) => {
677 let variant = tcx.adt_def(def_id).struct_variant();
679 // Encode def_ids for each field and method
680 // for methods, write all the stuff get_trait_method
682 let struct_ctor = if !struct_def.is_struct() {
683 Some(tcx.hir.local_def_id(struct_def.id()).index)
688 let repr_options = get_repr_options(&tcx, def_id);
690 EntryKind::Struct(self.lazy(&VariantData {
691 ctor_kind: variant.ctor_kind,
692 discr: variant.discr,
693 struct_ctor: struct_ctor,
696 hir::ItemUnion(..) => {
697 let variant = tcx.adt_def(def_id).struct_variant();
698 let repr_options = get_repr_options(&tcx, def_id);
700 EntryKind::Union(self.lazy(&VariantData {
701 ctor_kind: variant.ctor_kind,
702 discr: variant.discr,
706 hir::ItemDefaultImpl(..) => {
707 let data = ImplData {
708 polarity: hir::ImplPolarity::Positive,
709 defaultness: hir::Defaultness::Final,
711 coerce_unsized_info: None,
712 trait_ref: tcx.impl_trait_ref(def_id).map(|trait_ref| self.lazy(&trait_ref)),
715 EntryKind::DefaultImpl(self.lazy(&data))
717 hir::ItemImpl(_, polarity, defaultness, ..) => {
718 let trait_ref = tcx.impl_trait_ref(def_id);
719 let parent = if let Some(trait_ref) = trait_ref {
720 let trait_def = tcx.trait_def(trait_ref.def_id);
721 trait_def.ancestors(def_id).skip(1).next().and_then(|node| {
723 specialization_graph::Node::Impl(parent) => Some(parent),
731 // if this is an impl of `CoerceUnsized`, create its
732 // "unsized info", else just store None
733 let coerce_unsized_info =
734 trait_ref.and_then(|t| {
735 if Some(t.def_id) == tcx.lang_items.coerce_unsized_trait() {
736 Some(tcx.at(item.span).coerce_unsized_info(def_id))
742 let data = ImplData {
744 defaultness: defaultness,
746 coerce_unsized_info: coerce_unsized_info,
747 trait_ref: trait_ref.map(|trait_ref| self.lazy(&trait_ref)),
750 EntryKind::Impl(self.lazy(&data))
752 hir::ItemTrait(..) => {
753 let trait_def = tcx.trait_def(def_id);
754 let data = TraitData {
755 unsafety: trait_def.unsafety,
756 paren_sugar: trait_def.paren_sugar,
757 has_default_impl: tcx.trait_has_default_impl(def_id),
758 super_predicates: self.lazy(&tcx.super_predicates_of(def_id)),
761 EntryKind::Trait(self.lazy(&data))
763 hir::ItemExternCrate(_) |
764 hir::ItemUse(..) => bug!("cannot encode info for item {:?}", item),
769 visibility: self.lazy(&ty::Visibility::from_hir(&item.vis, item.id, tcx)),
770 span: self.lazy(&item.span),
771 attributes: self.encode_attributes(&item.attrs),
772 children: match item.node {
773 hir::ItemForeignMod(ref fm) => {
774 self.lazy_seq(fm.items
776 .map(|foreign_item| tcx.hir.local_def_id(foreign_item.id).index))
778 hir::ItemEnum(..) => {
779 let def = self.tcx.adt_def(def_id);
780 self.lazy_seq(def.variants.iter().map(|v| {
781 assert!(v.did.is_local());
785 hir::ItemStruct(..) |
786 hir::ItemUnion(..) => {
787 let def = self.tcx.adt_def(def_id);
788 self.lazy_seq(def.struct_variant().fields.iter().map(|f| {
789 assert!(f.did.is_local());
794 hir::ItemTrait(..) => {
795 self.lazy_seq(tcx.associated_item_def_ids(def_id).iter().map(|&def_id| {
796 assert!(def_id.is_local());
800 _ => LazySeq::empty(),
802 stability: self.encode_stability(def_id),
803 deprecation: self.encode_deprecation(def_id),
805 ty: match item.node {
806 hir::ItemStatic(..) |
811 hir::ItemStruct(..) |
813 hir::ItemImpl(..) => Some(self.encode_item_type(def_id)),
816 inherent_impls: self.encode_inherent_implementations(def_id),
817 variances: match item.node {
819 hir::ItemStruct(..) |
821 hir::ItemTrait(..) => self.encode_item_variances(def_id),
822 _ => LazySeq::empty(),
824 generics: match item.node {
825 hir::ItemStatic(..) |
830 hir::ItemStruct(..) |
833 hir::ItemTrait(..) => Some(self.encode_generics(def_id)),
836 predicates: match item.node {
837 hir::ItemStatic(..) |
842 hir::ItemStruct(..) |
845 hir::ItemTrait(..) => Some(self.encode_predicates(def_id)),
849 ast: match item.node {
850 hir::ItemConst(_, body) |
851 hir::ItemFn(_, _, hir::Constness::Const, _, _, body) => {
852 Some(self.encode_body(body))
856 mir: match item.node {
857 hir::ItemStatic(..) if self.tcx.sess.opts.debugging_opts.always_encode_mir => {
858 self.encode_mir(def_id)
860 hir::ItemConst(..) => self.encode_mir(def_id),
861 hir::ItemFn(_, _, constness, _, ref generics, _) => {
862 let tps_len = generics.ty_params.len();
863 let needs_inline = tps_len > 0 || attr::requests_inline(&item.attrs);
864 let always_encode_mir = self.tcx.sess.opts.debugging_opts.always_encode_mir;
865 if needs_inline || constness == hir::Constness::Const || always_encode_mir {
866 self.encode_mir(def_id)
876 /// Serialize the text of exported macros
877 fn encode_info_for_macro_def(&mut self, macro_def: &hir::MacroDef) -> Entry<'tcx> {
878 use syntax::print::pprust;
880 kind: EntryKind::MacroDef(self.lazy(&MacroDef {
881 body: pprust::tts_to_string(¯o_def.body.trees().collect::<Vec<_>>()),
883 visibility: self.lazy(&ty::Visibility::Public),
884 span: self.lazy(¯o_def.span),
886 attributes: self.encode_attributes(¯o_def.attrs),
887 children: LazySeq::empty(),
891 inherent_impls: LazySeq::empty(),
892 variances: LazySeq::empty(),
901 impl<'a, 'b, 'tcx> IndexBuilder<'a, 'b, 'tcx> {
902 /// In some cases, along with the item itself, we also
903 /// encode some sub-items. Usually we want some info from the item
904 /// so it's easier to do that here then to wait until we would encounter
905 /// normally in the visitor walk.
906 fn encode_addl_info_for_item(&mut self, item: &hir::Item) {
907 let def_id = self.tcx.hir.local_def_id(item.id);
909 hir::ItemStatic(..) |
913 hir::ItemForeignMod(..) |
914 hir::ItemGlobalAsm(..) |
915 hir::ItemExternCrate(..) |
917 hir::ItemDefaultImpl(..) |
919 // no sub-item recording needed in these cases
921 hir::ItemEnum(..) => {
922 self.encode_fields(def_id);
924 let def = self.tcx.adt_def(def_id);
925 for (i, variant) in def.variants.iter().enumerate() {
926 self.record(variant.did,
927 EntryBuilder::encode_enum_variant_info,
928 (def_id, Untracked(i)));
931 hir::ItemStruct(ref struct_def, _) => {
932 self.encode_fields(def_id);
934 // If the struct has a constructor, encode it.
935 if !struct_def.is_struct() {
936 let ctor_def_id = self.tcx.hir.local_def_id(struct_def.id());
937 self.record(ctor_def_id,
938 EntryBuilder::encode_struct_ctor,
939 (def_id, ctor_def_id));
942 hir::ItemUnion(..) => {
943 self.encode_fields(def_id);
945 hir::ItemImpl(..) => {
946 for &trait_item_def_id in self.tcx.associated_item_def_ids(def_id).iter() {
947 self.record(trait_item_def_id,
948 EntryBuilder::encode_info_for_impl_item,
952 hir::ItemTrait(..) => {
953 for &item_def_id in self.tcx.associated_item_def_ids(def_id).iter() {
954 self.record(item_def_id,
955 EntryBuilder::encode_info_for_trait_item,
963 impl<'a, 'b: 'a, 'tcx: 'b> EntryBuilder<'a, 'b, 'tcx> {
964 fn encode_info_for_foreign_item(&mut self,
965 (def_id, nitem): (DefId, &hir::ForeignItem))
969 debug!("EntryBuilder::encode_info_for_foreign_item({:?})", def_id);
971 let kind = match nitem.node {
972 hir::ForeignItemFn(_, ref names, _) => {
974 constness: hir::Constness::NotConst,
975 arg_names: self.encode_fn_arg_names(names),
977 EntryKind::ForeignFn(self.lazy(&data))
979 hir::ForeignItemStatic(_, true) => EntryKind::ForeignMutStatic,
980 hir::ForeignItemStatic(_, false) => EntryKind::ForeignImmStatic,
985 visibility: self.lazy(&ty::Visibility::from_hir(&nitem.vis, nitem.id, tcx)),
986 span: self.lazy(&nitem.span),
987 attributes: self.encode_attributes(&nitem.attrs),
988 children: LazySeq::empty(),
989 stability: self.encode_stability(def_id),
990 deprecation: self.encode_deprecation(def_id),
992 ty: Some(self.encode_item_type(def_id)),
993 inherent_impls: LazySeq::empty(),
994 variances: LazySeq::empty(),
995 generics: Some(self.encode_generics(def_id)),
996 predicates: Some(self.encode_predicates(def_id)),
1004 struct EncodeVisitor<'a, 'b: 'a, 'tcx: 'b> {
1005 index: IndexBuilder<'a, 'b, 'tcx>,
1008 impl<'a, 'b, 'tcx> Visitor<'tcx> for EncodeVisitor<'a, 'b, 'tcx> {
1009 fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'tcx> {
1010 NestedVisitorMap::OnlyBodies(&self.index.tcx.hir)
1012 fn visit_expr(&mut self, ex: &'tcx hir::Expr) {
1013 intravisit::walk_expr(self, ex);
1014 self.index.encode_info_for_expr(ex);
1016 fn visit_item(&mut self, item: &'tcx hir::Item) {
1017 intravisit::walk_item(self, item);
1018 let def_id = self.index.tcx.hir.local_def_id(item.id);
1020 hir::ItemExternCrate(_) |
1021 hir::ItemUse(..) => (), // ignore these
1022 _ => self.index.record(def_id, EntryBuilder::encode_info_for_item, (def_id, item)),
1024 self.index.encode_addl_info_for_item(item);
1026 fn visit_foreign_item(&mut self, ni: &'tcx hir::ForeignItem) {
1027 intravisit::walk_foreign_item(self, ni);
1028 let def_id = self.index.tcx.hir.local_def_id(ni.id);
1029 self.index.record(def_id,
1030 EntryBuilder::encode_info_for_foreign_item,
1033 fn visit_variant(&mut self,
1034 v: &'tcx hir::Variant,
1035 g: &'tcx hir::Generics,
1037 intravisit::walk_variant(self, v, g, id);
1039 if let Some(discr) = v.node.disr_expr {
1040 let def_id = self.index.tcx.hir.body_owner_def_id(discr);
1041 self.index.record(def_id, EntryBuilder::encode_info_for_embedded_const, def_id);
1044 fn visit_generics(&mut self, generics: &'tcx hir::Generics) {
1045 intravisit::walk_generics(self, generics);
1046 self.index.encode_info_for_generics(generics);
1048 fn visit_ty(&mut self, ty: &'tcx hir::Ty) {
1049 intravisit::walk_ty(self, ty);
1050 self.index.encode_info_for_ty(ty);
1052 fn visit_macro_def(&mut self, macro_def: &'tcx hir::MacroDef) {
1053 let def_id = self.index.tcx.hir.local_def_id(macro_def.id);
1054 self.index.record(def_id, EntryBuilder::encode_info_for_macro_def, macro_def);
1058 impl<'a, 'b, 'tcx> IndexBuilder<'a, 'b, 'tcx> {
1059 fn encode_info_for_generics(&mut self, generics: &hir::Generics) {
1060 for ty_param in &generics.ty_params {
1061 let def_id = self.tcx.hir.local_def_id(ty_param.id);
1062 let has_default = Untracked(ty_param.default.is_some());
1063 self.record(def_id, EntryBuilder::encode_info_for_ty_param, (def_id, has_default));
1067 fn encode_info_for_ty(&mut self, ty: &hir::Ty) {
1068 if let hir::TyImplTrait(_) = ty.node {
1069 let def_id = self.tcx.hir.local_def_id(ty.id);
1070 self.record(def_id, EntryBuilder::encode_info_for_anon_ty, def_id);
1074 fn encode_info_for_expr(&mut self, expr: &hir::Expr) {
1076 hir::ExprClosure(..) => {
1077 let def_id = self.tcx.hir.local_def_id(expr.id);
1078 self.record(def_id, EntryBuilder::encode_info_for_closure, def_id);
1085 impl<'a, 'b: 'a, 'tcx: 'b> EntryBuilder<'a, 'b, 'tcx> {
1086 fn encode_info_for_ty_param(&mut self,
1087 (def_id, Untracked(has_default)): (DefId, Untracked<bool>))
1089 debug!("EntryBuilder::encode_info_for_ty_param({:?})", def_id);
1092 kind: EntryKind::Type,
1093 visibility: self.lazy(&ty::Visibility::Public),
1094 span: self.lazy(&tcx.def_span(def_id)),
1095 attributes: LazySeq::empty(),
1096 children: LazySeq::empty(),
1100 ty: if has_default {
1101 Some(self.encode_item_type(def_id))
1105 inherent_impls: LazySeq::empty(),
1106 variances: LazySeq::empty(),
1115 fn encode_info_for_anon_ty(&mut self, def_id: DefId) -> Entry<'tcx> {
1116 debug!("EntryBuilder::encode_info_for_anon_ty({:?})", def_id);
1119 kind: EntryKind::Type,
1120 visibility: self.lazy(&ty::Visibility::Public),
1121 span: self.lazy(&tcx.def_span(def_id)),
1122 attributes: LazySeq::empty(),
1123 children: LazySeq::empty(),
1127 ty: Some(self.encode_item_type(def_id)),
1128 inherent_impls: LazySeq::empty(),
1129 variances: LazySeq::empty(),
1130 generics: Some(self.encode_generics(def_id)),
1131 predicates: Some(self.encode_predicates(def_id)),
1138 fn encode_info_for_closure(&mut self, def_id: DefId) -> Entry<'tcx> {
1139 debug!("EntryBuilder::encode_info_for_closure({:?})", def_id);
1142 let data = ClosureData {
1143 kind: tcx.closure_kind(def_id),
1144 ty: self.lazy(&tcx.closure_type(def_id)),
1148 kind: EntryKind::Closure(self.lazy(&data)),
1149 visibility: self.lazy(&ty::Visibility::Public),
1150 span: self.lazy(&tcx.def_span(def_id)),
1151 attributes: self.encode_attributes(&tcx.get_attrs(def_id)),
1152 children: LazySeq::empty(),
1156 ty: Some(self.encode_item_type(def_id)),
1157 inherent_impls: LazySeq::empty(),
1158 variances: LazySeq::empty(),
1159 generics: Some(self.encode_generics(def_id)),
1163 mir: self.encode_mir(def_id),
1167 fn encode_info_for_embedded_const(&mut self, def_id: DefId) -> Entry<'tcx> {
1168 debug!("EntryBuilder::encode_info_for_embedded_const({:?})", def_id);
1170 let id = tcx.hir.as_local_node_id(def_id).unwrap();
1171 let body = tcx.hir.body_owned_by(id);
1174 kind: EntryKind::Const(tcx.mir_const_qualif(def_id)),
1175 visibility: self.lazy(&ty::Visibility::Public),
1176 span: self.lazy(&tcx.def_span(def_id)),
1177 attributes: LazySeq::empty(),
1178 children: LazySeq::empty(),
1182 ty: Some(self.encode_item_type(def_id)),
1183 inherent_impls: LazySeq::empty(),
1184 variances: LazySeq::empty(),
1185 generics: Some(self.encode_generics(def_id)),
1186 predicates: Some(self.encode_predicates(def_id)),
1188 ast: Some(self.encode_body(body)),
1189 mir: self.encode_mir(def_id),
1193 fn encode_attributes(&mut self, attrs: &[ast::Attribute]) -> LazySeq<ast::Attribute> {
1194 // NOTE: This must use lazy_seq_from_slice(), not lazy_seq() because
1195 // we really on the HashStable specialization for [Attribute]
1196 // to properly filter things out.
1197 self.lazy_seq_from_slice(attrs)
1201 impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
1202 fn encode_info_for_items(&mut self) -> Index {
1203 let krate = self.tcx.hir.krate();
1204 let mut index = IndexBuilder::new(self);
1205 index.record(DefId::local(CRATE_DEF_INDEX),
1206 EntryBuilder::encode_info_for_mod,
1207 FromId(CRATE_NODE_ID, (&krate.module, &krate.attrs, &hir::Public)));
1208 let mut visitor = EncodeVisitor { index: index };
1209 krate.visit_all_item_likes(&mut visitor.as_deep_visitor());
1210 for macro_def in &krate.exported_macros {
1211 visitor.visit_macro_def(macro_def);
1213 visitor.index.into_items()
1216 fn encode_crate_deps(&mut self) -> LazySeq<CrateDep> {
1217 fn get_ordered_deps(cstore: &cstore::CStore) -> Vec<(CrateNum, Rc<cstore::CrateMetadata>)> {
1218 // Pull the cnums and name,vers,hash out of cstore
1219 let mut deps = Vec::new();
1220 cstore.iter_crate_data(|cnum, val| {
1221 deps.push((cnum, val.clone()));
1225 deps.sort_by(|kv1, kv2| kv1.0.cmp(&kv2.0));
1227 // Sanity-check the crate numbers
1228 let mut expected_cnum = 1;
1229 for &(n, _) in &deps {
1230 assert_eq!(n, CrateNum::new(expected_cnum));
1237 // We're just going to write a list of crate 'name-hash-version's, with
1238 // the assumption that they are numbered 1 to n.
1239 // FIXME (#2166): This is not nearly enough to support correct versioning
1240 // but is enough to get transitive crate dependencies working.
1241 let deps = get_ordered_deps(self.cstore);
1242 self.lazy_seq(deps.iter().map(|&(_, ref dep)| {
1246 kind: dep.dep_kind.get(),
1251 fn encode_lang_items(&mut self) -> (LazySeq<(DefIndex, usize)>, LazySeq<lang_items::LangItem>) {
1253 let lang_items = tcx.lang_items.items().iter();
1254 (self.lazy_seq(lang_items.enumerate().filter_map(|(i, &opt_def_id)| {
1255 if let Some(def_id) = opt_def_id {
1256 if def_id.is_local() {
1257 return Some((def_id.index, i));
1262 self.lazy_seq_ref(&tcx.lang_items.missing))
1265 fn encode_native_libraries(&mut self) -> LazySeq<NativeLibrary> {
1266 let used_libraries = self.tcx.sess.cstore.used_libraries();
1267 self.lazy_seq(used_libraries)
1270 fn encode_codemap(&mut self) -> LazySeq<syntax_pos::FileMap> {
1271 let codemap = self.tcx.sess.codemap();
1272 let all_filemaps = codemap.files.borrow();
1273 self.lazy_seq_ref(all_filemaps.iter()
1275 // No need to re-export imported filemaps, as any downstream
1276 // crate will import them from their original source.
1277 !filemap.is_imported()
1279 .map(|filemap| &**filemap))
1282 fn encode_def_path_table(&mut self) -> Lazy<DefPathTable> {
1283 let definitions = self.tcx.hir.definitions();
1284 self.lazy(definitions.def_path_table())
1288 struct ImplVisitor<'a, 'tcx: 'a> {
1289 tcx: TyCtxt<'a, 'tcx, 'tcx>,
1290 impls: FxHashMap<DefId, Vec<DefIndex>>,
1293 impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for ImplVisitor<'a, 'tcx> {
1294 fn visit_item(&mut self, item: &hir::Item) {
1295 if let hir::ItemImpl(..) = item.node {
1296 let impl_id = self.tcx.hir.local_def_id(item.id);
1297 if let Some(trait_ref) = self.tcx.impl_trait_ref(impl_id) {
1299 .entry(trait_ref.def_id)
1301 .push(impl_id.index);
1306 fn visit_trait_item(&mut self, _trait_item: &'v hir::TraitItem) {}
1308 fn visit_impl_item(&mut self, _impl_item: &'v hir::ImplItem) {
1309 // handled in `visit_item` above
1313 impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
1314 /// Encodes an index, mapping each trait to its (local) implementations.
1315 fn encode_impls(&mut self) -> LazySeq<TraitImpls> {
1316 let mut visitor = ImplVisitor {
1320 self.tcx.hir.krate().visit_all_item_likes(&mut visitor);
1322 let all_impls: Vec<_> = visitor.impls
1324 .map(|(trait_def_id, impls)| {
1326 trait_id: (trait_def_id.krate.as_u32(), trait_def_id.index),
1327 impls: self.lazy_seq(impls),
1332 self.lazy_seq(all_impls)
1335 // Encodes all symbols exported from this crate into the metadata.
1337 // This pass is seeded off the reachability list calculated in the
1338 // middle::reachable module but filters out items that either don't have a
1339 // symbol associated with them (they weren't translated) or if they're an FFI
1340 // definition (as that's not defined in this crate).
1341 fn encode_exported_symbols(&mut self) -> LazySeq<DefIndex> {
1342 let exported_symbols = self.exported_symbols;
1344 self.lazy_seq(exported_symbols.iter().map(|&id| tcx.hir.local_def_id(id).index))
1347 fn encode_dylib_dependency_formats(&mut self) -> LazySeq<Option<LinkagePreference>> {
1348 match self.tcx.sess.dependency_formats.borrow().get(&config::CrateTypeDylib) {
1350 self.lazy_seq(arr.iter().map(|slot| {
1352 Linkage::NotLinked |
1353 Linkage::IncludedFromDylib => None,
1355 Linkage::Dynamic => Some(LinkagePreference::RequireDynamic),
1356 Linkage::Static => Some(LinkagePreference::RequireStatic),
1360 None => LazySeq::empty(),
1365 impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
1366 fn encode_crate_root(&mut self) -> Lazy<CrateRoot> {
1367 let mut i = self.position();
1368 let crate_deps = self.encode_crate_deps();
1369 let dylib_dependency_formats = self.encode_dylib_dependency_formats();
1370 let dep_bytes = self.position() - i;
1372 // Encode the language items.
1373 i = self.position();
1374 let (lang_items, lang_items_missing) = self.encode_lang_items();
1375 let lang_item_bytes = self.position() - i;
1377 // Encode the native libraries used
1378 i = self.position();
1379 let native_libraries = self.encode_native_libraries();
1380 let native_lib_bytes = self.position() - i;
1383 i = self.position();
1384 let codemap = self.encode_codemap();
1385 let codemap_bytes = self.position() - i;
1387 // Encode DefPathTable
1388 i = self.position();
1389 let def_path_table = self.encode_def_path_table();
1390 let def_path_table_bytes = self.position() - i;
1392 // Encode the def IDs of impls, for coherence checking.
1393 i = self.position();
1394 let impls = self.encode_impls();
1395 let impl_bytes = self.position() - i;
1397 // Encode exported symbols info.
1398 i = self.position();
1399 let exported_symbols = self.encode_exported_symbols();
1400 let exported_symbols_bytes = self.position() - i;
1402 // Encode and index the items.
1403 i = self.position();
1404 let items = self.encode_info_for_items();
1405 let item_bytes = self.position() - i;
1407 i = self.position();
1408 let index = items.write_index(&mut self.opaque.cursor);
1409 let index_bytes = self.position() - i;
1412 let link_meta = self.link_meta;
1413 let is_proc_macro = tcx.sess.crate_types.borrow().contains(&CrateTypeProcMacro);
1414 let root = self.lazy(&CrateRoot {
1415 name: tcx.crate_name(LOCAL_CRATE),
1416 triple: tcx.sess.opts.target_triple.clone(),
1417 hash: link_meta.crate_hash,
1418 disambiguator: tcx.sess.local_crate_disambiguator(),
1419 panic_strategy: tcx.sess.panic_strategy(),
1420 plugin_registrar_fn: tcx.sess
1421 .plugin_registrar_fn
1423 .map(|id| tcx.hir.local_def_id(id).index),
1424 macro_derive_registrar: if is_proc_macro {
1425 let id = tcx.sess.derive_registrar_fn.get().unwrap();
1426 Some(tcx.hir.local_def_id(id).index)
1431 crate_deps: crate_deps,
1432 dylib_dependency_formats: dylib_dependency_formats,
1433 lang_items: lang_items,
1434 lang_items_missing: lang_items_missing,
1435 native_libraries: native_libraries,
1437 def_path_table: def_path_table,
1439 exported_symbols: exported_symbols,
1443 let total_bytes = self.position();
1445 if self.tcx.sess.meta_stats() {
1446 let mut zero_bytes = 0;
1447 for e in self.opaque.cursor.get_ref() {
1453 println!("metadata stats:");
1454 println!(" dep bytes: {}", dep_bytes);
1455 println!(" lang item bytes: {}", lang_item_bytes);
1456 println!(" native bytes: {}", native_lib_bytes);
1457 println!(" codemap bytes: {}", codemap_bytes);
1458 println!(" impl bytes: {}", impl_bytes);
1459 println!(" exp. symbols bytes: {}", exported_symbols_bytes);
1460 println!(" def-path table bytes: {}", def_path_table_bytes);
1461 println!(" item bytes: {}", item_bytes);
1462 println!(" index bytes: {}", index_bytes);
1463 println!(" zero bytes: {}", zero_bytes);
1464 println!(" total bytes: {}", total_bytes);
1471 // NOTE(eddyb) The following comment was preserved for posterity, even
1472 // though it's no longer relevant as EBML (which uses nested & tagged
1473 // "documents") was replaced with a scheme that can't go out of bounds.
1475 // And here we run into yet another obscure archive bug: in which metadata
1476 // loaded from archives may have trailing garbage bytes. Awhile back one of
1477 // our tests was failing sporadically on the macOS 64-bit builders (both nopt
1478 // and opt) by having ebml generate an out-of-bounds panic when looking at
1481 // Upon investigation it turned out that the metadata file inside of an rlib
1482 // (and ar archive) was being corrupted. Some compilations would generate a
1483 // metadata file which would end in a few extra bytes, while other
1484 // compilations would not have these extra bytes appended to the end. These
1485 // extra bytes were interpreted by ebml as an extra tag, so they ended up
1486 // being interpreted causing the out-of-bounds.
1488 // The root cause of why these extra bytes were appearing was never
1489 // discovered, and in the meantime the solution we're employing is to insert
1490 // the length of the metadata to the start of the metadata. Later on this
1491 // will allow us to slice the metadata to the precise length that we just
1492 // generated regardless of trailing bytes that end up in it.
1494 pub fn encode_metadata<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
1495 cstore: &cstore::CStore,
1496 link_meta: &LinkMeta,
1497 exported_symbols: &NodeSet)
1500 let mut cursor = Cursor::new(vec![]);
1501 cursor.write_all(METADATA_HEADER).unwrap();
1503 // Will be filed with the root position after encoding everything.
1504 cursor.write_all(&[0, 0, 0, 0]).unwrap();
1506 let (root, metadata_hashes) = {
1507 let mut ecx = EncodeContext {
1508 opaque: opaque::Encoder::new(&mut cursor),
1510 link_meta: link_meta,
1512 exported_symbols: exported_symbols,
1513 lazy_state: LazyState::NoNode,
1514 type_shorthands: Default::default(),
1515 predicate_shorthands: Default::default(),
1516 metadata_hashes: Vec::new(),
1519 // Encode the rustc version string in a predictable location.
1520 rustc_version().encode(&mut ecx).unwrap();
1522 // Encode all the entries and extra information in the crate,
1523 // culminating in the `CrateRoot` which points to all of it.
1524 let root = ecx.encode_crate_root();
1525 (root, ecx.metadata_hashes)
1527 let mut result = cursor.into_inner();
1529 // Encode the root position.
1530 let header = METADATA_HEADER.len();
1531 let pos = root.position;
1532 result[header + 0] = (pos >> 24) as u8;
1533 result[header + 1] = (pos >> 16) as u8;
1534 result[header + 2] = (pos >> 8) as u8;
1535 result[header + 3] = (pos >> 0) as u8;
1539 hashes: metadata_hashes,
1543 pub fn get_repr_options<'a, 'tcx, 'gcx>(tcx: &TyCtxt<'a, 'tcx, 'gcx>, did: DefId) -> ReprOptions {
1544 let ty = tcx.type_of(did);
1546 ty::TyAdt(ref def, _) => return def.repr,
1547 _ => bug!("{} is not an ADT", ty),