4 use rustc::hir::def::{self, CtorKind};
5 use rustc::hir::def_id::{DefIndex, DefId, CrateNum};
6 use rustc::ich::StableHashingContext;
7 use rustc::middle::cstore::{DepKind, LinkagePreference, NativeLibrary, ForeignModule};
8 use rustc::middle::lang_items;
10 use rustc::session::CrateDisambiguator;
11 use rustc::ty::{self, Ty, ReprOptions};
12 use rustc_target::spec::{PanicStrategy, TargetTriple};
13 use rustc_data_structures::svh::Svh;
15 use rustc_serialize as serialize;
16 use syntax::{ast, attr};
17 use syntax::edition::Edition;
18 use syntax::symbol::Symbol;
19 use syntax_pos::{self, Span};
21 use std::marker::PhantomData;
24 use rustc_data_structures::stable_hasher::{StableHasher, HashStable,
27 pub fn rustc_version() -> String {
29 option_env!("CFG_VERSION").unwrap_or("unknown version"))
32 /// Metadata encoding version.
33 /// N.B., increment this if you change the format of metadata such that
34 /// the rustc version can't be found to compare with `rustc_version()`.
35 pub const METADATA_VERSION: u8 = 4;
37 /// Metadata header which includes `METADATA_VERSION`.
38 /// To get older versions of rustc to ignore this metadata,
39 /// there are 4 zero bytes at the start, which are treated
40 /// as a length of 0 by old compilers.
42 /// This header is followed by the position of the `CrateRoot`,
43 /// which is encoded as a 32-bit big-endian unsigned integer,
44 /// and further followed by the rustc version string.
45 pub const METADATA_HEADER: &[u8; 12] =
46 &[0, 0, 0, 0, b'r', b'u', b's', b't', 0, 0, 0, METADATA_VERSION];
48 /// A value of type T referred to by its absolute position
49 /// in the metadata, and which can be decoded lazily.
51 /// Metadata is effective a tree, encoded in post-order,
52 /// and with the root's position written next to the header.
53 /// That means every single `Lazy` points to some previous
54 /// location in the metadata and is part of a larger node.
56 /// The first `Lazy` in a node is encoded as the backwards
57 /// distance from the position where the containing node
58 /// starts and where the `Lazy` points to, while the rest
59 /// use the forward distance from the previous `Lazy`.
60 /// Distances start at 1, as 0-byte nodes are invalid.
61 /// Also invalid are nodes being referred in a different
62 /// order than they were encoded in.
66 _marker: PhantomData<T>,
70 pub fn with_position(position: usize) -> Lazy<T> {
77 /// Returns the minimum encoded size of a value of type `T`.
78 // FIXME(eddyb) Give better estimates for certain types.
79 pub fn min_size() -> usize {
84 impl<T> Copy for Lazy<T> {}
85 impl<T> Clone for Lazy<T> {
86 fn clone(&self) -> Self {
91 impl<T> serialize::UseSpecializedEncodable for Lazy<T> {}
92 impl<T> serialize::UseSpecializedDecodable for Lazy<T> {}
94 impl<CTX, T> HashStable<CTX> for Lazy<T> {
95 fn hash_stable<W: StableHasherResult>(&self,
97 _: &mut StableHasher<W>) {
98 // There's nothing to do. Whatever got encoded within this Lazy<>
99 // wrapper has already been hashed.
103 /// A sequence of type T referred to by its absolute position
104 /// in the metadata and length, and which can be decoded lazily.
105 /// The sequence is a single node for the purposes of `Lazy`.
107 /// Unlike `Lazy<Vec<T>>`, the length is encoded next to the
108 /// position, not at the position, which means that the length
109 /// doesn't need to be known before encoding all the elements.
111 /// If the length is 0, no position is encoded, but otherwise,
112 /// the encoding is that of `Lazy`, with the distinction that
113 /// the minimal distance the length of the sequence, i.e.
114 /// it's assumed there's no 0-byte element in the sequence.
116 pub struct LazySeq<T> {
119 _marker: PhantomData<T>,
123 pub fn empty() -> LazySeq<T> {
124 LazySeq::with_position_and_length(0, 0)
127 pub fn with_position_and_length(position: usize, len: usize) -> LazySeq<T> {
131 _marker: PhantomData,
135 /// Returns the minimum encoded size of `length` values of type `T`.
136 pub fn min_size(length: usize) -> usize {
141 impl<T> Copy for LazySeq<T> {}
142 impl<T> Clone for LazySeq<T> {
143 fn clone(&self) -> Self {
148 impl<T> serialize::UseSpecializedEncodable for LazySeq<T> {}
149 impl<T> serialize::UseSpecializedDecodable for LazySeq<T> {}
151 impl<CTX, T> HashStable<CTX> for LazySeq<T> {
152 fn hash_stable<W: StableHasherResult>(&self,
154 _: &mut StableHasher<W>) {
155 // There's nothing to do. Whatever got encoded within this Lazy<>
156 // wrapper has already been hashed.
160 /// Encoding / decoding state for `Lazy` and `LazySeq`.
161 #[derive(Copy, Clone, PartialEq, Eq, Debug)]
163 /// Outside of a metadata node.
166 /// Inside a metadata node, and before any `Lazy` or `LazySeq`.
167 /// The position is that of the node itself.
170 /// Inside a metadata node, with a previous `Lazy` or `LazySeq`.
171 /// The position is a conservative estimate of where that
172 /// previous `Lazy` / `LazySeq` would end (see their comments).
176 #[derive(RustcEncodable, RustcDecodable)]
177 pub struct CrateRoot {
179 pub triple: TargetTriple,
180 pub extra_filename: String,
182 pub disambiguator: CrateDisambiguator,
183 pub panic_strategy: PanicStrategy,
184 pub edition: Edition,
185 pub has_global_allocator: bool,
186 pub has_panic_handler: bool,
187 pub has_default_lib_allocator: bool,
188 pub plugin_registrar_fn: Option<DefIndex>,
189 pub proc_macro_decls_static: Option<DefIndex>,
191 pub crate_deps: LazySeq<CrateDep>,
192 pub dylib_dependency_formats: LazySeq<Option<LinkagePreference>>,
193 pub lib_features: LazySeq<(Symbol, Option<Symbol>)>,
194 pub lang_items: LazySeq<(DefIndex, usize)>,
195 pub lang_items_missing: LazySeq<lang_items::LangItem>,
196 pub native_libraries: LazySeq<NativeLibrary>,
197 pub foreign_modules: LazySeq<ForeignModule>,
198 pub source_map: LazySeq<syntax_pos::SourceFile>,
199 pub def_path_table: Lazy<hir::map::definitions::DefPathTable>,
200 pub impls: LazySeq<TraitImpls>,
201 pub exported_symbols: EncodedExportedSymbols,
202 pub interpret_alloc_index: LazySeq<u32>,
204 pub index: LazySeq<index::Index>,
206 pub compiler_builtins: bool,
207 pub needs_allocator: bool,
208 pub needs_panic_runtime: bool,
209 pub no_builtins: bool,
210 pub panic_runtime: bool,
211 pub profiler_runtime: bool,
212 pub sanitizer_runtime: bool,
215 #[derive(RustcEncodable, RustcDecodable)]
216 pub struct CrateDep {
220 pub extra_filename: String,
223 impl_stable_hash_for!(struct CrateDep {
230 #[derive(RustcEncodable, RustcDecodable)]
231 pub struct TraitImpls {
232 pub trait_id: (u32, DefIndex),
233 pub impls: LazySeq<DefIndex>,
236 impl<'a, 'gcx> HashStable<StableHashingContext<'a>> for TraitImpls {
237 fn hash_stable<W: StableHasherResult>(&self,
238 hcx: &mut StableHashingContext<'a>,
239 hasher: &mut StableHasher<W>) {
241 trait_id: (krate, def_index),
246 krate: CrateNum::from_u32(krate),
248 }.hash_stable(hcx, hasher);
249 impls.hash_stable(hcx, hasher);
253 #[derive(RustcEncodable, RustcDecodable)]
254 pub struct Entry<'tcx> {
255 pub kind: EntryKind<'tcx>,
256 pub visibility: Lazy<ty::Visibility>,
257 pub span: Lazy<Span>,
258 pub attributes: LazySeq<ast::Attribute>,
259 pub children: LazySeq<DefIndex>,
260 pub stability: Option<Lazy<attr::Stability>>,
261 pub deprecation: Option<Lazy<attr::Deprecation>>,
263 pub ty: Option<Lazy<Ty<'tcx>>>,
264 pub inherent_impls: LazySeq<DefIndex>,
265 pub variances: LazySeq<ty::Variance>,
266 pub generics: Option<Lazy<ty::Generics>>,
267 pub predicates: Option<Lazy<ty::GenericPredicates<'tcx>>>,
268 pub predicates_defined_on: Option<Lazy<ty::GenericPredicates<'tcx>>>,
270 pub mir: Option<Lazy<mir::Mir<'tcx>>>,
273 impl_stable_hash_for!(struct Entry<'tcx> {
286 predicates_defined_on,
290 #[derive(Copy, Clone, RustcEncodable, RustcDecodable)]
291 pub enum EntryKind<'tcx> {
292 Const(ConstQualif, Lazy<RenderedConst>),
304 Variant(Lazy<VariantData<'tcx>>),
305 Struct(Lazy<VariantData<'tcx>>, ReprOptions),
306 Union(Lazy<VariantData<'tcx>>, ReprOptions),
307 Fn(Lazy<FnData<'tcx>>),
308 ForeignFn(Lazy<FnData<'tcx>>),
310 MacroDef(Lazy<MacroDef>),
311 Closure(Lazy<ClosureData<'tcx>>),
312 Generator(Lazy<GeneratorData<'tcx>>),
313 Trait(Lazy<TraitData<'tcx>>),
314 Impl(Lazy<ImplData<'tcx>>),
315 Method(Lazy<MethodData<'tcx>>),
316 AssociatedType(AssociatedContainer),
317 AssociatedExistential(AssociatedContainer),
318 AssociatedConst(AssociatedContainer, ConstQualif, Lazy<RenderedConst>),
321 impl<'a, 'gcx> HashStable<StableHashingContext<'a>> for EntryKind<'gcx> {
322 fn hash_stable<W: StableHasherResult>(&self,
323 hcx: &mut StableHashingContext<'a>,
324 hasher: &mut StableHasher<W>) {
325 mem::discriminant(self).hash_stable(hcx, hasher);
327 EntryKind::ImmStatic |
328 EntryKind::MutStatic |
329 EntryKind::ForeignImmStatic |
330 EntryKind::ForeignMutStatic |
331 EntryKind::ForeignMod |
332 EntryKind::GlobalAsm |
333 EntryKind::ForeignType |
335 EntryKind::Existential |
337 // Nothing else to hash here.
339 EntryKind::Const(qualif, ref const_data) => {
340 qualif.hash_stable(hcx, hasher);
341 const_data.hash_stable(hcx, hasher);
343 EntryKind::Enum(ref repr_options) => {
344 repr_options.hash_stable(hcx, hasher);
346 EntryKind::Variant(ref variant_data) => {
347 variant_data.hash_stable(hcx, hasher);
349 EntryKind::Struct(ref variant_data, ref repr_options) |
350 EntryKind::Union(ref variant_data, ref repr_options) => {
351 variant_data.hash_stable(hcx, hasher);
352 repr_options.hash_stable(hcx, hasher);
354 EntryKind::Fn(ref fn_data) |
355 EntryKind::ForeignFn(ref fn_data) => {
356 fn_data.hash_stable(hcx, hasher);
358 EntryKind::Mod(ref mod_data) => {
359 mod_data.hash_stable(hcx, hasher);
361 EntryKind::MacroDef(ref macro_def) => {
362 macro_def.hash_stable(hcx, hasher);
364 EntryKind::Generator(data) => {
365 data.hash_stable(hcx, hasher);
367 EntryKind::Closure(closure_data) => {
368 closure_data.hash_stable(hcx, hasher);
370 EntryKind::Trait(ref trait_data) => {
371 trait_data.hash_stable(hcx, hasher);
373 EntryKind::Impl(ref impl_data) => {
374 impl_data.hash_stable(hcx, hasher);
376 EntryKind::Method(ref method_data) => {
377 method_data.hash_stable(hcx, hasher);
379 EntryKind::AssociatedExistential(associated_container) |
380 EntryKind::AssociatedType(associated_container) => {
381 associated_container.hash_stable(hcx, hasher);
383 EntryKind::AssociatedConst(associated_container, qualif, ref const_data) => {
384 associated_container.hash_stable(hcx, hasher);
385 qualif.hash_stable(hcx, hasher);
386 const_data.hash_stable(hcx, hasher);
392 /// Additional data for EntryKind::Const and EntryKind::AssociatedConst
393 #[derive(Clone, Copy, RustcEncodable, RustcDecodable)]
394 pub struct ConstQualif {
396 pub ast_promotable: bool,
399 impl_stable_hash_for!(struct ConstQualif { mir, ast_promotable });
401 /// Contains a constant which has been rendered to a String.
403 #[derive(RustcEncodable, RustcDecodable)]
404 pub struct RenderedConst(pub String);
406 impl<'a> HashStable<StableHashingContext<'a>> for RenderedConst {
408 fn hash_stable<W: StableHasherResult>(&self,
409 hcx: &mut StableHashingContext<'a>,
410 hasher: &mut StableHasher<W>) {
411 self.0.hash_stable(hcx, hasher);
415 #[derive(RustcEncodable, RustcDecodable)]
417 pub reexports: LazySeq<def::Export>,
420 impl_stable_hash_for!(struct ModData { reexports });
422 #[derive(RustcEncodable, RustcDecodable)]
423 pub struct MacroDef {
428 impl_stable_hash_for!(struct MacroDef { body, legacy });
430 #[derive(RustcEncodable, RustcDecodable)]
431 pub struct FnData<'tcx> {
432 pub constness: hir::Constness,
433 pub arg_names: LazySeq<ast::Name>,
434 pub sig: Lazy<ty::PolyFnSig<'tcx>>,
437 impl_stable_hash_for!(struct FnData<'tcx> { constness, arg_names, sig });
439 #[derive(RustcEncodable, RustcDecodable)]
440 pub struct VariantData<'tcx> {
441 pub ctor_kind: CtorKind,
442 pub discr: ty::VariantDiscr,
444 /// If this is a struct's only variant, this
445 /// is the index of the "struct ctor" item.
446 pub struct_ctor: Option<DefIndex>,
448 /// If this is a tuple struct or variant
449 /// ctor, this is its "function" signature.
450 pub ctor_sig: Option<Lazy<ty::PolyFnSig<'tcx>>>,
453 impl_stable_hash_for!(struct VariantData<'tcx> {
460 #[derive(RustcEncodable, RustcDecodable)]
461 pub struct TraitData<'tcx> {
462 pub unsafety: hir::Unsafety,
463 pub paren_sugar: bool,
464 pub has_auto_impl: bool,
466 pub super_predicates: Lazy<ty::GenericPredicates<'tcx>>,
469 impl_stable_hash_for!(struct TraitData<'tcx> {
477 #[derive(RustcEncodable, RustcDecodable)]
478 pub struct ImplData<'tcx> {
479 pub polarity: hir::ImplPolarity,
480 pub defaultness: hir::Defaultness,
481 pub parent_impl: Option<DefId>,
483 /// This is `Some` only for impls of `CoerceUnsized`.
484 pub coerce_unsized_info: Option<ty::adjustment::CoerceUnsizedInfo>,
485 pub trait_ref: Option<Lazy<ty::TraitRef<'tcx>>>,
488 impl_stable_hash_for!(struct ImplData<'tcx> {
497 /// Describes whether the container of an associated item
498 /// is a trait or an impl and whether, in a trait, it has
499 /// a default, or an in impl, whether it's marked "default".
500 #[derive(Copy, Clone, RustcEncodable, RustcDecodable)]
501 pub enum AssociatedContainer {
508 impl_stable_hash_for!(enum ::schema::AssociatedContainer {
515 impl AssociatedContainer {
516 pub fn with_def_id(&self, def_id: DefId) -> ty::AssociatedItemContainer {
518 AssociatedContainer::TraitRequired |
519 AssociatedContainer::TraitWithDefault => ty::TraitContainer(def_id),
521 AssociatedContainer::ImplDefault |
522 AssociatedContainer::ImplFinal => ty::ImplContainer(def_id),
526 pub fn defaultness(&self) -> hir::Defaultness {
528 AssociatedContainer::TraitRequired => hir::Defaultness::Default {
532 AssociatedContainer::TraitWithDefault |
533 AssociatedContainer::ImplDefault => hir::Defaultness::Default {
537 AssociatedContainer::ImplFinal => hir::Defaultness::Final,
542 #[derive(RustcEncodable, RustcDecodable)]
543 pub struct MethodData<'tcx> {
544 pub fn_data: FnData<'tcx>,
545 pub container: AssociatedContainer,
548 impl_stable_hash_for!(struct MethodData<'tcx> { fn_data, container, has_self });
550 #[derive(RustcEncodable, RustcDecodable)]
551 pub struct ClosureData<'tcx> {
552 pub sig: Lazy<ty::PolyFnSig<'tcx>>,
554 impl_stable_hash_for!(struct ClosureData<'tcx> { sig });
556 #[derive(RustcEncodable, RustcDecodable)]
557 pub struct GeneratorData<'tcx> {
558 pub layout: mir::GeneratorLayout<'tcx>,
560 impl_stable_hash_for!(struct GeneratorData<'tcx> { layout });
562 // Tags used for encoding Spans:
563 pub const TAG_VALID_SPAN: u8 = 0;
564 pub const TAG_INVALID_SPAN: u8 = 1;
566 #[derive(RustcEncodable, RustcDecodable)]
567 pub struct EncodedExportedSymbols {