1 // Copyright 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.
11 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
12 // file at the top-level directory of this distribution and at
13 // http://rust-lang.org/COPYRIGHT.
15 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
16 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
17 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
18 // option. This file may not be copied, modified, or distributed
19 // except according to those terms.
21 // the rustc crate store interface. This also includes types that
22 // are *mostly* used as a part of that interface, but these should
23 // probably get a better home if someone can find one.
26 use front::map as hir_map;
27 use middle::def::{self, Def};
28 use middle::lang_items;
29 use middle::ty::{self, Ty, VariantKind};
30 use middle::def_id::{DefId, DefIndex};
33 use session::search_paths::PathKind;
34 use util::nodemap::{FnvHashMap, NodeMap, NodeSet};
36 use std::cell::RefCell;
38 use std::path::PathBuf;
40 use syntax::ast_util::{IdVisitingOperation};
42 use syntax::codemap::Span;
44 use rustc_back::target::Target;
46 use rustc_front::intravisit::Visitor;
47 use rustc_front::util::IdVisitor;
49 pub use self::DefLike::{DlDef, DlField, DlImpl};
50 pub use self::NativeLibraryKind::{NativeStatic, NativeFramework, NativeUnknown};
52 // lonely orphan structs and enums looking for a better home
54 #[derive(Clone, Debug)]
56 pub crate_name: String,
60 // Where a crate came from on the local filesystem. One of these two options
62 #[derive(PartialEq, Clone, Debug)]
63 pub struct CrateSource {
64 pub dylib: Option<(PathBuf, PathKind)>,
65 pub rlib: Option<(PathBuf, PathKind)>,
66 pub cnum: ast::CrateNum,
69 #[derive(Copy, Debug, PartialEq, Clone)]
70 pub enum LinkagePreference {
76 #[derive(Copy, Clone, PartialEq)]
77 pub enum NativeLibraryKind {
78 NativeStatic, // native static library (.a archive)
79 NativeFramework, // OSX-specific
80 NativeUnknown, // default way to specify a dynamic library
84 // Something that a name can resolve to.
85 #[derive(Copy, Clone, Debug)]
92 /// The data we save and restore about an inlined item or method. This is not
93 /// part of the AST that we parse from a file, but it becomes part of the tree
95 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
96 pub enum InlinedItem {
98 TraitItem(DefId /* impl id */, P<hir::TraitItem>),
99 ImplItem(DefId /* impl id */, P<hir::ImplItem>),
100 Foreign(P<hir::ForeignItem>),
103 /// A borrowed version of `hir::InlinedItem`.
104 #[derive(Clone, Copy, PartialEq, Eq, Hash, Debug)]
105 pub enum InlinedItemRef<'a> {
107 TraitItem(DefId, &'a hir::TraitItem),
108 ImplItem(DefId, &'a hir::ImplItem),
109 Foreign(&'a hir::ForeignItem)
112 /// Item definitions in the currently-compiled crate would have the CrateNum
113 /// LOCAL_CRATE in their DefId.
114 pub const LOCAL_CRATE: ast::CrateNum = 0;
116 pub struct ChildItem {
119 pub vis: hir::Visibility
122 pub enum FoundAst<'ast> {
123 Found(&'ast InlinedItem),
124 FoundParent(DefId, &'ast InlinedItem),
128 /// A store of Rust crates, through with their metadata
131 /// The `: Any` bound is a temporary measure that allows access
132 /// to the backing `rustc_metadata::cstore::CStore` object. It
133 /// will be removed in the near future - if you need to access
134 /// internal APIs, please tell us.
135 pub trait CrateStore<'tcx> : Any {
137 fn stability(&self, def: DefId) -> Option<attr::Stability>;
138 fn deprecation(&self, def: DefId) -> Option<attr::Deprecation>;
139 fn closure_kind(&self, tcx: &ty::ctxt<'tcx>, def_id: DefId)
141 fn closure_ty(&self, tcx: &ty::ctxt<'tcx>, def_id: DefId)
142 -> ty::ClosureTy<'tcx>;
143 fn item_variances(&self, def: DefId) -> ty::ItemVariances;
144 fn repr_attrs(&self, def: DefId) -> Vec<attr::ReprAttr>;
145 fn item_type(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
146 -> ty::TypeScheme<'tcx>;
147 fn item_path(&self, def: DefId) -> Vec<hir_map::PathElem>;
148 fn extern_item_path(&self, def: DefId) -> Vec<hir_map::PathElem>;
149 fn item_name(&self, def: DefId) -> ast::Name;
150 fn item_predicates(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
151 -> ty::GenericPredicates<'tcx>;
152 fn item_super_predicates(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
153 -> ty::GenericPredicates<'tcx>;
154 fn item_attrs(&self, def_id: DefId) -> Vec<ast::Attribute>;
155 fn item_symbol(&self, def: DefId) -> String;
156 fn trait_def(&self, tcx: &ty::ctxt<'tcx>, def: DefId)-> ty::TraitDef<'tcx>;
157 fn adt_def(&self, tcx: &ty::ctxt<'tcx>, def: DefId) -> ty::AdtDefMaster<'tcx>;
158 fn method_arg_names(&self, did: DefId) -> Vec<String>;
159 fn inherent_implementations_for_type(&self, def_id: DefId) -> Vec<DefId>;
162 fn implementations_of_trait(&self, def_id: DefId) -> Vec<DefId>;
163 fn provided_trait_methods(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
164 -> Vec<Rc<ty::Method<'tcx>>>;
165 fn trait_item_def_ids(&self, def: DefId)
166 -> Vec<ty::ImplOrTraitItemId>;
169 fn impl_items(&self, impl_def_id: DefId) -> Vec<ty::ImplOrTraitItemId>;
170 fn impl_trait_ref(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
171 -> Option<ty::TraitRef<'tcx>>;
172 fn impl_polarity(&self, def: DefId) -> Option<hir::ImplPolarity>;
173 fn custom_coerce_unsized_kind(&self, def: DefId)
174 -> Option<ty::adjustment::CustomCoerceUnsized>;
175 fn associated_consts(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
176 -> Vec<Rc<ty::AssociatedConst<'tcx>>>;
178 // trait/impl-item info
179 fn trait_of_item(&self, tcx: &ty::ctxt<'tcx>, def_id: DefId)
181 fn impl_or_trait_item(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
182 -> ty::ImplOrTraitItem<'tcx>;
185 fn is_const_fn(&self, did: DefId) -> bool;
186 fn is_defaulted_trait(&self, did: DefId) -> bool;
187 fn is_impl(&self, did: DefId) -> bool;
188 fn is_default_impl(&self, impl_did: DefId) -> bool;
189 fn is_extern_fn(&self, tcx: &ty::ctxt<'tcx>, did: DefId) -> bool;
190 fn is_static(&self, did: DefId) -> bool;
191 fn is_static_method(&self, did: DefId) -> bool;
192 fn is_statically_included_foreign_item(&self, id: ast::NodeId) -> bool;
193 fn is_typedef(&self, did: DefId) -> bool;
196 fn dylib_dependency_formats(&self, cnum: ast::CrateNum)
197 -> Vec<(ast::CrateNum, LinkagePreference)>;
198 fn lang_items(&self, cnum: ast::CrateNum) -> Vec<(DefIndex, usize)>;
199 fn missing_lang_items(&self, cnum: ast::CrateNum) -> Vec<lang_items::LangItem>;
200 fn is_staged_api(&self, cnum: ast::CrateNum) -> bool;
201 fn is_explicitly_linked(&self, cnum: ast::CrateNum) -> bool;
202 fn is_allocator(&self, cnum: ast::CrateNum) -> bool;
203 fn crate_attrs(&self, cnum: ast::CrateNum) -> Vec<ast::Attribute>;
204 fn crate_name(&self, cnum: ast::CrateNum) -> String;
205 fn crate_hash(&self, cnum: ast::CrateNum) -> Svh;
206 fn crate_struct_field_attrs(&self, cnum: ast::CrateNum)
207 -> FnvHashMap<DefId, Vec<ast::Attribute>>;
208 fn plugin_registrar_fn(&self, cnum: ast::CrateNum) -> Option<DefId>;
209 fn native_libraries(&self, cnum: ast::CrateNum) -> Vec<(NativeLibraryKind, String)>;
210 fn reachable_ids(&self, cnum: ast::CrateNum) -> Vec<DefId>;
213 fn def_path(&self, def: DefId) -> hir_map::DefPath;
214 fn variant_kind(&self, def_id: DefId) -> Option<VariantKind>;
215 fn struct_ctor_def_id(&self, struct_def_id: DefId) -> Option<DefId>;
216 fn tuple_struct_definition_if_ctor(&self, did: DefId) -> Option<DefId>;
217 fn struct_field_names(&self, def: DefId) -> Vec<ast::Name>;
218 fn item_children(&self, did: DefId) -> Vec<ChildItem>;
219 fn crate_top_level_items(&self, cnum: ast::CrateNum) -> Vec<ChildItem>;
222 fn maybe_get_item_ast(&'tcx self, tcx: &ty::ctxt<'tcx>, def: DefId)
224 fn maybe_get_item_mir(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
225 -> Option<Mir<'tcx>>;
226 // This is basically a 1-based range of ints, which is a little
227 // silly - I may fix that.
228 fn crates(&self) -> Vec<ast::CrateNum>;
229 fn used_libraries(&self) -> Vec<(String, NativeLibraryKind)>;
230 fn used_link_args(&self) -> Vec<String>;
233 fn metadata_filename(&self) -> &str;
234 fn metadata_section_name(&self, target: &Target) -> &str;
235 fn encode_type(&self, tcx: &ty::ctxt<'tcx>, ty: Ty<'tcx>) -> Vec<u8>;
236 fn used_crates(&self, prefer: LinkagePreference) -> Vec<(ast::CrateNum, Option<PathBuf>)>;
237 fn used_crate_source(&self, cnum: ast::CrateNum) -> CrateSource;
238 fn extern_mod_stmt_cnum(&self, emod_id: ast::NodeId) -> Option<ast::CrateNum>;
239 fn encode_metadata(&self,
240 tcx: &ty::ctxt<'tcx>,
241 reexports: &def::ExportMap,
242 item_symbols: &RefCell<NodeMap<String>>,
243 link_meta: &LinkMeta,
245 mir_map: &NodeMap<Mir<'tcx>>,
246 krate: &hir::Crate) -> Vec<u8>;
247 fn metadata_encoding_version(&self) -> &[u8];
251 pub fn visit<'ast,V>(&'ast self, visitor: &mut V)
252 where V: Visitor<'ast>
255 InlinedItem::Item(ref i) => visitor.visit_item(&**i),
256 InlinedItem::Foreign(ref i) => visitor.visit_foreign_item(&**i),
257 InlinedItem::TraitItem(_, ref ti) => visitor.visit_trait_item(ti),
258 InlinedItem::ImplItem(_, ref ii) => visitor.visit_impl_item(ii),
262 pub fn visit_ids<O: IdVisitingOperation>(&self, operation: &mut O) {
263 let mut id_visitor = IdVisitor::new(operation);
264 self.visit(&mut id_visitor);
268 // FIXME: find a better place for this?
269 pub fn validate_crate_name(sess: Option<&Session>, s: &str, sp: Option<Span>) {
270 let mut err_count = 0;
272 let mut say = |s: &str| {
274 (_, None) => panic!("{}", s),
275 (Some(sp), Some(sess)) => sess.span_err(sp, s),
276 (None, Some(sess)) => sess.err(s),
281 say("crate name must not be empty");
284 if c.is_alphanumeric() { continue }
285 if c == '_' { continue }
286 say(&format!("invalid character `{}` in crate name: `{}`", c, s));
291 sess.unwrap().abort_if_errors();
295 /// A dummy crate store that does not support any non-local crates,
296 /// for test purposes.
297 pub struct DummyCrateStore;
298 #[allow(unused_variables)]
299 impl<'tcx> CrateStore<'tcx> for DummyCrateStore {
301 fn stability(&self, def: DefId) -> Option<attr::Stability> { unimplemented!() }
302 fn deprecation(&self, def: DefId) -> Option<attr::Deprecation> { unimplemented!() }
303 fn closure_kind(&self, tcx: &ty::ctxt<'tcx>, def_id: DefId)
304 -> ty::ClosureKind { unimplemented!() }
305 fn closure_ty(&self, tcx: &ty::ctxt<'tcx>, def_id: DefId)
306 -> ty::ClosureTy<'tcx> { unimplemented!() }
307 fn item_variances(&self, def: DefId) -> ty::ItemVariances { unimplemented!() }
308 fn repr_attrs(&self, def: DefId) -> Vec<attr::ReprAttr> { unimplemented!() }
309 fn item_type(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
310 -> ty::TypeScheme<'tcx> { unimplemented!() }
311 fn item_path(&self, def: DefId) -> Vec<hir_map::PathElem> { unimplemented!() }
312 fn extern_item_path(&self, def: DefId) -> Vec<hir_map::PathElem> { unimplemented!() }
313 fn item_name(&self, def: DefId) -> ast::Name { unimplemented!() }
314 fn item_predicates(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
315 -> ty::GenericPredicates<'tcx> { unimplemented!() }
316 fn item_super_predicates(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
317 -> ty::GenericPredicates<'tcx> { unimplemented!() }
318 fn item_attrs(&self, def_id: DefId) -> Vec<ast::Attribute> { unimplemented!() }
319 fn item_symbol(&self, def: DefId) -> String { unimplemented!() }
320 fn trait_def(&self, tcx: &ty::ctxt<'tcx>, def: DefId)-> ty::TraitDef<'tcx>
322 fn adt_def(&self, tcx: &ty::ctxt<'tcx>, def: DefId) -> ty::AdtDefMaster<'tcx>
324 fn method_arg_names(&self, did: DefId) -> Vec<String> { unimplemented!() }
325 fn inherent_implementations_for_type(&self, def_id: DefId) -> Vec<DefId> { vec![] }
328 fn implementations_of_trait(&self, def_id: DefId) -> Vec<DefId> { vec![] }
329 fn provided_trait_methods(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
330 -> Vec<Rc<ty::Method<'tcx>>> { unimplemented!() }
331 fn trait_item_def_ids(&self, def: DefId)
332 -> Vec<ty::ImplOrTraitItemId> { unimplemented!() }
335 fn impl_items(&self, impl_def_id: DefId) -> Vec<ty::ImplOrTraitItemId>
337 fn impl_trait_ref(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
338 -> Option<ty::TraitRef<'tcx>> { unimplemented!() }
339 fn impl_polarity(&self, def: DefId) -> Option<hir::ImplPolarity> { unimplemented!() }
340 fn custom_coerce_unsized_kind(&self, def: DefId)
341 -> Option<ty::adjustment::CustomCoerceUnsized>
343 fn associated_consts(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
344 -> Vec<Rc<ty::AssociatedConst<'tcx>>> { unimplemented!() }
346 // trait/impl-item info
347 fn trait_of_item(&self, tcx: &ty::ctxt<'tcx>, def_id: DefId)
348 -> Option<DefId> { unimplemented!() }
349 fn impl_or_trait_item(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
350 -> ty::ImplOrTraitItem<'tcx> { unimplemented!() }
353 fn is_const_fn(&self, did: DefId) -> bool { unimplemented!() }
354 fn is_defaulted_trait(&self, did: DefId) -> bool { unimplemented!() }
355 fn is_impl(&self, did: DefId) -> bool { unimplemented!() }
356 fn is_default_impl(&self, impl_did: DefId) -> bool { unimplemented!() }
357 fn is_extern_fn(&self, tcx: &ty::ctxt<'tcx>, did: DefId) -> bool { unimplemented!() }
358 fn is_static(&self, did: DefId) -> bool { unimplemented!() }
359 fn is_static_method(&self, did: DefId) -> bool { unimplemented!() }
360 fn is_statically_included_foreign_item(&self, id: ast::NodeId) -> bool { false }
361 fn is_typedef(&self, did: DefId) -> bool { unimplemented!() }
364 fn dylib_dependency_formats(&self, cnum: ast::CrateNum)
365 -> Vec<(ast::CrateNum, LinkagePreference)>
367 fn lang_items(&self, cnum: ast::CrateNum) -> Vec<(DefIndex, usize)>
369 fn missing_lang_items(&self, cnum: ast::CrateNum) -> Vec<lang_items::LangItem>
371 fn is_staged_api(&self, cnum: ast::CrateNum) -> bool { unimplemented!() }
372 fn is_explicitly_linked(&self, cnum: ast::CrateNum) -> bool { unimplemented!() }
373 fn is_allocator(&self, cnum: ast::CrateNum) -> bool { unimplemented!() }
374 fn crate_attrs(&self, cnum: ast::CrateNum) -> Vec<ast::Attribute>
376 fn crate_name(&self, cnum: ast::CrateNum) -> String { unimplemented!() }
377 fn crate_hash(&self, cnum: ast::CrateNum) -> Svh { unimplemented!() }
378 fn crate_struct_field_attrs(&self, cnum: ast::CrateNum)
379 -> FnvHashMap<DefId, Vec<ast::Attribute>>
381 fn plugin_registrar_fn(&self, cnum: ast::CrateNum) -> Option<DefId>
383 fn native_libraries(&self, cnum: ast::CrateNum) -> Vec<(NativeLibraryKind, String)>
385 fn reachable_ids(&self, cnum: ast::CrateNum) -> Vec<DefId> { unimplemented!() }
388 fn def_path(&self, def: DefId) -> hir_map::DefPath { unimplemented!() }
389 fn variant_kind(&self, def_id: DefId) -> Option<VariantKind> { unimplemented!() }
390 fn struct_ctor_def_id(&self, struct_def_id: DefId) -> Option<DefId>
392 fn tuple_struct_definition_if_ctor(&self, did: DefId) -> Option<DefId>
394 fn struct_field_names(&self, def: DefId) -> Vec<ast::Name> { unimplemented!() }
395 fn item_children(&self, did: DefId) -> Vec<ChildItem> { unimplemented!() }
396 fn crate_top_level_items(&self, cnum: ast::CrateNum) -> Vec<ChildItem>
400 fn maybe_get_item_ast(&'tcx self, tcx: &ty::ctxt<'tcx>, def: DefId)
401 -> FoundAst<'tcx> { unimplemented!() }
402 fn maybe_get_item_mir(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
403 -> Option<Mir<'tcx>> { unimplemented!() }
405 // This is basically a 1-based range of ints, which is a little
406 // silly - I may fix that.
407 fn crates(&self) -> Vec<ast::CrateNum> { vec![] }
408 fn used_libraries(&self) -> Vec<(String, NativeLibraryKind)> { vec![] }
409 fn used_link_args(&self) -> Vec<String> { vec![] }
412 fn metadata_filename(&self) -> &str { unimplemented!() }
413 fn metadata_section_name(&self, target: &Target) -> &str { unimplemented!() }
414 fn encode_type(&self, tcx: &ty::ctxt<'tcx>, ty: Ty<'tcx>) -> Vec<u8>
416 fn used_crates(&self, prefer: LinkagePreference) -> Vec<(ast::CrateNum, Option<PathBuf>)>
418 fn used_crate_source(&self, cnum: ast::CrateNum) -> CrateSource { unimplemented!() }
419 fn extern_mod_stmt_cnum(&self, emod_id: ast::NodeId) -> Option<ast::CrateNum> { None }
420 fn encode_metadata(&self,
421 tcx: &ty::ctxt<'tcx>,
422 reexports: &def::ExportMap,
423 item_symbols: &RefCell<NodeMap<String>>,
424 link_meta: &LinkMeta,
426 mir_map: &NodeMap<Mir<'tcx>>,
427 krate: &hir::Crate) -> Vec<u8> { vec![] }
428 fn metadata_encoding_version(&self) -> &[u8] { unimplemented!() }
432 /// Metadata encoding and decoding can make use of thread-local encoding and
433 /// decoding contexts. These allow implementers of serialize::Encodable and
434 /// Decodable to access information and datastructures that would otherwise not
435 /// be available to them. For example, we can automatically translate def-id and
436 /// span information during decoding because the decoding context knows which
437 /// crate the data is decoded from. Or it allows to make ty::Ty decodable
438 /// because the context has access to the ty::ctxt that is needed for creating
439 /// ty::Ty instances.
441 /// Note, however, that this only works for RBML-based encoding and decoding at
444 use rbml::opaque::Encoder as OpaqueEncoder;
445 use rbml::opaque::Decoder as OpaqueDecoder;
448 use middle::ty::{self, Ty};
449 use middle::subst::Substs;
450 use middle::def_id::DefId;
452 pub trait EncodingContext<'tcx> {
453 fn tcx<'a>(&'a self) -> &'a ty::ctxt<'tcx>;
454 fn encode_ty(&self, encoder: &mut OpaqueEncoder, t: Ty<'tcx>);
455 fn encode_substs(&self, encoder: &mut OpaqueEncoder, substs: &Substs<'tcx>);
458 /// Marker type used for the scoped TLS slot.
459 /// The type context cannot be used directly because the scoped TLS
460 /// in libstd doesn't allow types generic over lifetimes.
463 scoped_thread_local!(static TLS_ENCODING: TlsPayload);
465 /// Execute f after pushing the given EncodingContext onto the TLS stack.
466 pub fn enter_encoding_context<'tcx, F, R>(ecx: &EncodingContext<'tcx>,
467 encoder: &mut OpaqueEncoder,
469 where F: FnOnce(&EncodingContext<'tcx>, &mut OpaqueEncoder) -> R
471 let tls_payload = (ecx as *const _, encoder as *mut _);
472 let tls_ptr = &tls_payload as *const _ as *const TlsPayload;
473 TLS_ENCODING.set(unsafe { &*tls_ptr }, || f(ecx, encoder))
476 /// Execute f with access to the thread-local encoding context and
477 /// rbml encoder. This function will panic if the encoder passed in and the
478 /// context encoder are not the same.
480 /// Note that this method is 'practically' safe due to its checking that the
481 /// encoder passed in is the same as the one in TLS, but it would still be
482 /// possible to construct cases where the EncodingContext is exchanged
483 /// while the same encoder is used, thus working with a wrong context.
484 pub fn with_encoding_context<'tcx, E, F, R>(encoder: &mut E, f: F) -> R
485 where F: FnOnce(&EncodingContext<'tcx>, &mut OpaqueEncoder) -> R,
486 E: serialize::Encoder
489 unsafe_with_encoding_context(|ecx, tls_encoder| {
490 assert!(encoder as *mut _ as usize == tls_encoder as *mut _ as usize);
492 let ecx: &EncodingContext<'tcx> = mem::transmute(ecx);
499 /// Execute f with access to the thread-local encoding context and
501 pub unsafe fn unsafe_with_encoding_context<F, R>(f: F) -> R
502 where F: FnOnce(&EncodingContext, &mut OpaqueEncoder) -> R
504 TLS_ENCODING.with(|tls| {
505 let tls_payload = (tls as *const TlsPayload)
506 as *mut (&EncodingContext, &mut OpaqueEncoder);
507 f((*tls_payload).0, (*tls_payload).1)
511 pub trait DecodingContext<'tcx> {
512 fn tcx<'a>(&'a self) -> &'a ty::ctxt<'tcx>;
513 fn decode_ty(&self, decoder: &mut OpaqueDecoder) -> ty::Ty<'tcx>;
514 fn decode_substs(&self, decoder: &mut OpaqueDecoder) -> Substs<'tcx>;
515 fn translate_def_id(&self, def_id: DefId) -> DefId;
518 scoped_thread_local!(static TLS_DECODING: TlsPayload);
520 /// Execute f after pushing the given DecodingContext onto the TLS stack.
521 pub fn enter_decoding_context<'tcx, F, R>(dcx: &DecodingContext<'tcx>,
522 decoder: &mut OpaqueDecoder,
524 where F: FnOnce(&DecodingContext<'tcx>, &mut OpaqueDecoder) -> R
526 let tls_payload = (dcx as *const _, decoder as *mut _);
527 let tls_ptr = &tls_payload as *const _ as *const TlsPayload;
528 TLS_DECODING.set(unsafe { &*tls_ptr }, || f(dcx, decoder))
531 /// Execute f with access to the thread-local decoding context and
532 /// rbml decoder. This function will panic if the decoder passed in and the
533 /// context decoder are not the same.
535 /// Note that this method is 'practically' safe due to its checking that the
536 /// decoder passed in is the same as the one in TLS, but it would still be
537 /// possible to construct cases where the DecodingContext is exchanged
538 /// while the same decoder is used, thus working with a wrong context.
539 pub fn with_decoding_context<'decoder, 'tcx, D, F, R>(d: &'decoder mut D, f: F) -> R
540 where D: serialize::Decoder,
541 F: FnOnce(&DecodingContext<'tcx>,
542 &mut OpaqueDecoder) -> R,
546 unsafe_with_decoding_context(|dcx, decoder| {
547 assert!((d as *mut _ as usize) == (decoder as *mut _ as usize));
549 let dcx: &DecodingContext<'tcx> = mem::transmute(dcx);
556 /// Execute f with access to the thread-local decoding context and
558 pub unsafe fn unsafe_with_decoding_context<F, R>(f: F) -> R
559 where F: FnOnce(&DecodingContext, &mut OpaqueDecoder) -> R
561 TLS_DECODING.with(|tls| {
562 let tls_payload = (tls as *const TlsPayload)
563 as *mut (&DecodingContext, &mut OpaqueDecoder);
564 f((*tls_payload).0, (*tls_payload).1)