charon_driver/translate/
translate_meta.rs

1//! Translate information about items: name, attributes, etc.
2use itertools::Itertools;
3use rustc_middle::mir;
4use rustc_span::RemapPathScopeComponents;
5use std::cmp::Ord;
6use std::path::{Component, PathBuf};
7
8use super::translate_crate::RustcItem;
9use super::translate_ctx::*;
10use super::translate_generics::BindingLevel;
11use charon_lib::ast::*;
12use hax::{DefPathItem, SInto};
13
14// Spans
15impl<'tcx, 'ctx> TranslateCtx<'tcx> {
16    /// Register a file if it is a "real" file and was not already registered
17    /// `span` must be a span from which we obtained that filename.
18    fn register_file(&mut self, filename: FileName, span: rustc_span::Span) -> FileId {
19        // Lookup the file if it was already registered
20        match self.file_to_id.get(&filename) {
21            Some(id) => *id,
22            None => {
23                let source_file = self.tcx.sess.source_map().lookup_source_file(span.lo());
24                let crate_name = self.tcx.crate_name(source_file.cnum).to_string();
25                let file = File {
26                    name: filename.clone(),
27                    crate_name,
28                    contents: source_file.src.as_deref().cloned(),
29                };
30                let id = self.translated.files.push(file);
31                self.file_to_id.insert(filename, id);
32                id
33            }
34        }
35    }
36
37    pub fn translate_filename(&mut self, name: rustc_span::FileName) -> meta::FileName {
38        match name {
39            rustc_span::FileName::Real(name) => {
40                match name.local_path() {
41                    Some(path) => {
42                        let path = if let Ok(path) = path.strip_prefix(&self.sysroot) {
43                            // The path to files in the standard library may be full paths to somewhere
44                            // in the sysroot. This may depend on how the toolchain is installed
45                            // (rustup vs nix), so we normalize the paths here to avoid
46                            // inconsistencies in the translation.
47                            if let Ok(path) = path.strip_prefix("lib/rustlib/src/rust") {
48                                let mut rewritten_path: PathBuf = "/rustc".into();
49                                rewritten_path.extend(path);
50                                rewritten_path
51                            } else {
52                                // Unclear if this can happen, but just in case.
53                                let mut rewritten_path: PathBuf = "/toolchain".into();
54                                rewritten_path.extend(path);
55                                rewritten_path
56                            }
57                        } else {
58                            // Find the cargo home directory: according to cargo docs and having a
59                            // look at the cargo source, it's either the `$CARGO_HOME` var or
60                            // `$HOME/.cargo`
61                            let cargo_home = std::env::var("CARGO_HOME")
62                                .map(PathBuf::from)
63                                .ok()
64                                .or_else(|| std::env::home_dir().map(|p| p.join(".cargo")));
65                            if let Some(cargo_home) = cargo_home
66                                && let Ok(path) = path.strip_prefix(cargo_home)
67                            {
68                                // Avoid some more machine-dependent paths in the llbc output.
69                                let mut rewritten_path: PathBuf = "/cargo".into();
70                                rewritten_path.extend(path);
71                                rewritten_path
72                            } else {
73                                path.into()
74                            }
75                        };
76                        FileName::Local(path)
77                    }
78                    None => {
79                        // We use the virtual name because it is always available.
80                        // That name normally starts with `/rustc/<hash>/`. For our purposes we hide
81                        // the hash.
82                        let virtual_name = name.path(RemapPathScopeComponents::MACRO);
83                        let mut components_iter = virtual_name.components();
84                        if let Some(
85                            [
86                                Component::RootDir,
87                                Component::Normal(rustc),
88                                Component::Normal(hash),
89                            ],
90                        ) = components_iter.by_ref().array_chunks().next()
91                            && rustc.to_str() == Some("rustc")
92                            && hash.len() == 40
93                        {
94                            let path_without_hash = [Component::RootDir, Component::Normal(rustc)]
95                                .into_iter()
96                                .chain(components_iter)
97                                .collect();
98                            FileName::Virtual(path_without_hash)
99                        } else {
100                            FileName::Virtual(virtual_name.into())
101                        }
102                    }
103                }
104            }
105            // We use the debug formatter to generate a filename.
106            // This is not ideal, but filenames are for debugging anyway.
107            _ => FileName::NotReal(format!("{name:?}")),
108        }
109    }
110
111    pub fn translate_span_data(&mut self, span: rustc_span::Span) -> meta::SpanData {
112        let smap: &rustc_span::source_map::SourceMap = self.tcx.sess.psess.source_map();
113        let filename = smap.span_to_filename(span);
114        let filename = self.translate_filename(filename);
115        let span = span;
116        let file_id = match &filename {
117            FileName::NotReal(_) => {
118                // For now we forbid not real filenames
119                unimplemented!();
120            }
121            FileName::Virtual(_) | FileName::Local(_) => self.register_file(filename, span),
122        };
123
124        let convert_loc = |pos: rustc_span::BytePos| -> Loc {
125            let loc = smap.lookup_char_pos(pos);
126            Loc {
127                line: loc.line,
128                col: loc.col_display,
129            }
130        };
131        let beg = convert_loc(span.lo());
132        let end = convert_loc(span.hi());
133
134        // Put together
135        meta::SpanData { file_id, beg, end }
136    }
137
138    /// Compute span data from a Rust source scope
139    pub fn translate_span_from_source_info(
140        &mut self,
141        source_scopes: &rustc_index::IndexVec<mir::SourceScope, mir::SourceScopeData>,
142        source_info: &mir::SourceInfo,
143    ) -> Span {
144        // Translate the span
145        let data = self.translate_span_data(source_info.span);
146
147        // Lookup the top-most inlined parent scope.
148        let mut parent_span = None;
149        let mut scope_data = &source_scopes[source_info.scope];
150        while let Some(parent_scope) = scope_data.inlined_parent_scope {
151            scope_data = &source_scopes[parent_scope];
152            parent_span = Some(scope_data.span);
153        }
154
155        if let Some(parent_span) = parent_span {
156            let parent_span = self.translate_span_data(parent_span);
157            Span {
158                data: parent_span,
159                generated_from_span: Some(data),
160            }
161        } else {
162            Span {
163                data,
164                generated_from_span: None,
165            }
166        }
167    }
168
169    pub(crate) fn translate_span(&mut self, span: &rustc_span::Span) -> Span {
170        Span {
171            data: self.translate_span_data(*span),
172            generated_from_span: None,
173        }
174    }
175
176    pub(crate) fn def_span(&mut self, def_id: &hax::DefId) -> Span {
177        let span = def_id.def_span(&self.hax_state);
178        self.translate_span(&span)
179    }
180}
181
182// Names
183impl<'tcx, 'ctx> TranslateCtx<'tcx> {
184    fn path_elem_for_def(
185        &mut self,
186        span: Span,
187        item: &RustcItem,
188    ) -> Result<Option<PathElem>, Error> {
189        let def_id = item.def_id();
190        let path_elem = def_id.path_item(&self.hax_state);
191        // Disambiguator disambiguates identically-named (but distinct) identifiers. This happens
192        // notably with macros and inherent impl blocks.
193        let disambiguator = Disambiguator::new(path_elem.disambiguator as usize);
194        // Match over the key data
195        let path_elem = match path_elem.data {
196            DefPathItem::CrateRoot { name, .. } => {
197                // Sanity check
198                error_assert!(self, span, path_elem.disambiguator == 0);
199                Some(PathElem::Ident(name.to_string(), disambiguator))
200            }
201            // We map the three namespaces onto a single one. We can always disambiguate by looking
202            // at the definition.
203            DefPathItem::TypeNs(symbol)
204            | DefPathItem::ValueNs(symbol)
205            | DefPathItem::MacroNs(symbol) => {
206                Some(PathElem::Ident(symbol.to_string(), disambiguator))
207            }
208            DefPathItem::Impl => {
209                let full_def = self.hax_def_for_item(item)?;
210                // Two cases, depending on whether the impl block is
211                // a "regular" impl block (`impl Foo { ... }`) or a trait
212                // implementation (`impl Bar for Foo { ... }`).
213                let impl_elem = match full_def.kind() {
214                    // Inherent impl ("regular" impl)
215                    hax::FullDefKind::InherentImpl { ty, .. } => {
216                        // We need to convert the type, which may contain quantified
217                        // substs and bounds. In order to properly do so, we introduce
218                        // a body translation context.
219                        let item_src =
220                            TransItemSource::new(item.clone(), TransItemSourceKind::InherentImpl);
221                        let mut bt_ctx = ItemTransCtx::new(item_src, None, self);
222                        bt_ctx.translate_item_generics(
223                            span,
224                            &full_def,
225                            &TransItemSourceKind::InherentImpl,
226                        )?;
227                        let ty = bt_ctx.translate_ty(span, &ty)?;
228                        ImplElem::Ty(Binder {
229                            kind: BinderKind::InherentImplBlock,
230                            params: bt_ctx.into_generics(),
231                            skip_binder: ty,
232                        })
233                    }
234                    // Trait implementation
235                    hax::FullDefKind::TraitImpl { .. } => {
236                        let impl_id = {
237                            let item_src = TransItemSource::new(
238                                item.clone(),
239                                TransItemSourceKind::TraitImpl(TraitImplSource::Normal),
240                            );
241                            self.register_and_enqueue(&None, item_src).unwrap()
242                        };
243                        ImplElem::Trait(impl_id)
244                    }
245                    _ => unreachable!(),
246                };
247
248                Some(PathElem::Impl(impl_elem))
249            }
250            // TODO: do nothing for now
251            DefPathItem::OpaqueTy => None,
252            // TODO: this is not very satisfactory, but on the other hand
253            // we should be able to extract closures in local let-bindings
254            // (i.e., we shouldn't have to introduce top-level let-bindings).
255            DefPathItem::Closure => Some(PathElem::Ident("closure".to_string(), disambiguator)),
256            // Do nothing, functions in `extern` blocks are in the same namespace as the
257            // block.
258            DefPathItem::ForeignMod => None,
259            // Do nothing, the constructor of a struct/variant has the same name as the
260            // struct/variant.
261            DefPathItem::Ctor => None,
262            DefPathItem::Use => Some(PathElem::Ident("{use}".to_string(), disambiguator)),
263            DefPathItem::AnonConst => Some(PathElem::Ident("{const}".to_string(), disambiguator)),
264            DefPathItem::PromotedConst => Some(PathElem::Ident(
265                "{promoted_const}".to_string(),
266                disambiguator,
267            )),
268            _ => {
269                raise_error!(
270                    self,
271                    span,
272                    "Unexpected DefPathItem for `{def_id:?}`: {path_elem:?}"
273                );
274            }
275        };
276        Ok(path_elem)
277    }
278
279    /// Retrieve the name for this [`hax::DefId`]. Because a given `DefId` may give rise to several
280    /// charon items, prefer to use `translate_name` when possible.
281    ///
282    /// We lookup the path associated to an id, and convert it to a name.
283    /// Paths very precisely identify where an item is. There are important
284    /// subcases, like the items in an `Impl` block:
285    /// ```ignore
286    /// impl<T> List<T> {
287    ///   fn new() ...
288    /// }
289    /// ```
290    ///
291    /// One issue here is that "List" *doesn't appear* in the path, which would
292    /// look like the following:
293    ///
294    ///   `TypeNS("Crate") :: Impl :: ValueNs("new")`
295    ///                       ^^^
296    ///           This is where "List" should be
297    ///
298    /// For this reason, whenever we find an `Impl` path element, we actually
299    /// lookup the type of the sub-path, from which we can derive a name.
300    ///
301    /// Besides, as there may be several "impl" blocks for one type, each impl
302    /// block is identified by a unique number (rustc calls this a
303    /// "disambiguator"), which we grab.
304    ///
305    /// Example:
306    /// ========
307    /// For instance, if we write the following code in crate `test` and module
308    /// `bla`:
309    /// ```ignore
310    /// impl<T> Foo<T> {
311    ///   fn foo() { ... }
312    /// }
313    ///
314    /// impl<T> Foo<T> {
315    ///   fn bar() { ... }
316    /// }
317    /// ```
318    ///
319    /// The names we will generate for `foo` and `bar` are:
320    /// `[Ident("test"), Ident("bla"), Ident("Foo"), Impl(impl<T> Ty<T>, Disambiguator(0)), Ident("foo")]`
321    /// `[Ident("test"), Ident("bla"), Ident("Foo"), Impl(impl<T> Ty<T>, Disambiguator(1)), Ident("bar")]`
322    fn name_for_item(&mut self, item: &RustcItem) -> Result<Name, Error> {
323        if let Some(name) = self.cached_names.get(item) {
324            return Ok(name.clone());
325        }
326        let def_id = item.def_id();
327        trace!("Computing name for `{def_id:?}`");
328
329        let parent_name = if let Some(parent_id) = def_id.parent(&self.hax_state) {
330            let def = self.hax_def_for_item(item)?;
331            if matches!(item, RustcItem::Mono(..))
332                && let Some(parent_item) = def.typing_parent(&self.hax_state)
333            {
334                self.name_for_item(&RustcItem::Mono(parent_item.clone()))?
335            } else {
336                self.name_for_item(&RustcItem::Poly(parent_id.clone()))?
337            }
338        } else {
339            Name { name: Vec::new() }
340        };
341        let span = self.def_span(def_id);
342        let mut name = parent_name;
343        if let Some(path_elem) = self.path_elem_for_def(span, item)? {
344            name.name.push(path_elem);
345        }
346
347        trace!("Computed name for `{def_id:?}`: `{name:?}`");
348        self.cached_names.insert(item.clone(), name.clone());
349        Ok(name)
350    }
351
352    /// Compute the name for an item.
353    /// Internal function, use `translate_name`.
354    pub fn name_for_src(&mut self, src: &TransItemSource) -> Result<Name, Error> {
355        let mut name = if let Some(parent) = src.parent() {
356            self.name_for_src(&parent)?
357        } else {
358            self.name_for_item(&src.item)?
359        };
360        match &src.kind {
361            // Nothing to do for the real items.
362            TransItemSourceKind::Type
363            | TransItemSourceKind::Fun
364            | TransItemSourceKind::Global
365            | TransItemSourceKind::TraitImpl(TraitImplSource::Normal)
366            | TransItemSourceKind::TraitDecl
367            | TransItemSourceKind::InherentImpl
368            | TransItemSourceKind::Module => {}
369
370            TransItemSourceKind::TraitImpl(
371                kind @ (TraitImplSource::Closure(..)
372                | TraitImplSource::ImplicitDestruct
373                | TraitImplSource::TraitAlias),
374            ) => {
375                if let TraitImplSource::Closure(..) = kind {
376                    let _ = name.name.pop(); // Pop the `{closure}`
377                }
378                let impl_id = self.register_and_enqueue(&None, src.clone()).unwrap();
379                name.name.push(PathElem::Impl(ImplElem::Trait(impl_id)));
380            }
381            TransItemSourceKind::DefaultedMethod(_, method_name) => {
382                name.name.push(PathElem::Ident(
383                    method_name.to_string(),
384                    Disambiguator::ZERO,
385                ));
386            }
387            TransItemSourceKind::ClosureMethod(kind) => {
388                let fn_name = kind.method_name().to_string();
389                name.name
390                    .push(PathElem::Ident(fn_name, Disambiguator::ZERO));
391            }
392            TransItemSourceKind::DropInPlaceMethod(..) => {
393                name.name.push(PathElem::Ident(
394                    "drop_in_place".to_string(),
395                    Disambiguator::ZERO,
396                ));
397            }
398            TransItemSourceKind::ClosureAsFnCast => {
399                name.name
400                    .push(PathElem::Ident("as_fn".into(), Disambiguator::ZERO));
401            }
402            TransItemSourceKind::VTable
403            | TransItemSourceKind::VTableInstance(..)
404            | TransItemSourceKind::VTableInstanceInitializer(..) => {
405                name.name
406                    .push(PathElem::Ident("{vtable}".into(), Disambiguator::ZERO));
407            }
408            TransItemSourceKind::VTableMethod => {
409                name.name.push(PathElem::Ident(
410                    "{vtable_method}".into(),
411                    Disambiguator::ZERO,
412                ));
413            }
414            TransItemSourceKind::VTableDropShim => {
415                name.name.push(PathElem::Ident(
416                    "{vtable_drop_shim}".into(),
417                    Disambiguator::ZERO,
418                ));
419            }
420            TransItemSourceKind::VTableDropPreShim => {
421                name.name.push(PathElem::Ident(
422                    "{vtable_drop_preshim}".into(),
423                    Disambiguator::ZERO,
424                ));
425            }
426            TransItemSourceKind::VTableMethodPreShim(_, method_name) => {
427                name.name.push(PathElem::Ident(
428                    method_name.to_string(),
429                    Disambiguator::ZERO,
430                ));
431                name.name.push(PathElem::Ident(
432                    "{vtable_method_preshim}".into(),
433                    Disambiguator::ZERO,
434                ));
435            }
436        }
437        Ok(name)
438    }
439
440    /// Retrieve the name for an item.
441    pub fn translate_name(&mut self, src: &TransItemSource) -> Result<Name, Error> {
442        let mut name = self.name_for_src(src)?;
443        // Push the generics used for monomorphization, if any.
444        if let RustcItem::Mono(item_ref) = &src.item
445            && !item_ref.generic_args.is_empty()
446        {
447            // For preshim functions in Mono mode, we compute their generic and associative arguments,
448            // which are appended to the name of these functions.
449            let is_preshim = matches!(
450                src.kind,
451                TransItemSourceKind::VTableDropPreShim
452                    | TransItemSourceKind::VTableMethodPreShim(..)
453            );
454
455            let trans_id = self.register_no_enqueue(&None, src).unwrap();
456            let span = self.def_span(&item_ref.def_id);
457            let mut bt_ctx = ItemTransCtx::new(src.clone(), trans_id, self);
458            bt_ctx.binding_levels.push(BindingLevel::new());
459
460            let trait_def = bt_ctx.t_ctx.hax_def_for_item(&src.item)?;
461            let mut assoc_types = None;
462
463            // fetch associative arguments
464            if let hax::FullDefKind::Trait { items, .. } = trait_def.kind() {
465                for item in items {
466                    if matches!(item.kind, hax::AssocKind::Type { .. }) {
467                        let item_def_id = &item.def_id;
468                        // This is ok because dyn-compatible methods don't have generics.
469                        let item_def = bt_ctx.hax_def(
470                            &trait_def
471                                .this()
472                                .with_def_id(bt_ctx.hax_state(), item_def_id),
473                        )?;
474                        if let hax::FullDefKind::AssocTy {
475                            implied_predicates, ..
476                        } = item_def.kind()
477                        {
478                            if let Some(pred) = implied_predicates.predicates.first() {
479                                if let hax::ClauseKind::Trait(p) = &pred.clause.kind.value {
480                                    assoc_types = Some(p.trait_ref.generic_args.clone());
481                                    break;
482                                }
483                            }
484                        }
485                    }
486                }
487            }
488            // fetch generic arguments
489            let mut substs = item_ref.generic_args.clone();
490
491            if !(is_preshim && item_ref.generic_args.len() == 1 && matches!(assoc_types, None)) {
492                // For preshim functions, skip the first argument, which is the dyn trait type.
493                let args = if is_preshim {
494                    if let Some(mut assoc_types) = assoc_types {
495                        substs.append(&mut assoc_types);
496                    }
497                    bt_ctx.translate_generic_args(span, &substs[1..], &item_ref.impl_exprs)?
498                } else {
499                    bt_ctx.translate_generic_args(span, &substs, &item_ref.impl_exprs)?
500                };
501                name.name.push(PathElem::Instantiated(Box::new(Binder {
502                    params: GenericParams::empty(),
503                    skip_binder: args,
504                    kind: BinderKind::Other,
505                })));
506            }
507        }
508        Ok(name)
509    }
510
511    /// Remark: this **doesn't** register the def id (on purpose)
512    pub(crate) fn translate_trait_item_name(
513        &mut self,
514        def_id: &hax::DefId,
515    ) -> Result<TraitItemName, Error> {
516        let def = self.poly_hax_def(def_id)?;
517        let assoc = match def.kind() {
518            hax::FullDefKind::AssocTy {
519                associated_item, ..
520            }
521            | hax::FullDefKind::AssocConst {
522                associated_item, ..
523            }
524            | hax::FullDefKind::AssocFn {
525                associated_item, ..
526            } => associated_item,
527            _ => panic!("Unexpected def for associated item: {def:?}"),
528        };
529        Ok(TraitItemName(
530            assoc
531                .name
532                .as_ref()
533                .map(|n| n.to_string().into())
534                .unwrap_or_default(),
535        ))
536    }
537
538    pub(crate) fn opacity_for_name(&self, name: &Name) -> ItemOpacity {
539        self.options.opacity_for_name(&self.translated, name)
540    }
541}
542
543// Attributes
544impl<'tcx, 'ctx> TranslateCtx<'tcx> {
545    /// Parse a raw attribute to recognize our special `charon::*`, `aeneas::*` and `verify::*` attributes.
546    fn parse_attr_from_raw(
547        &mut self,
548        def_id: &hax::DefId,
549        raw_attr: RawAttribute,
550    ) -> Result<Attribute, String> {
551        // If the attribute path has two components, the first of which is `charon` or `aeneas`, we
552        // try to parse it. Otherwise we return `Unknown`.
553        let path = raw_attr.path.split("::").collect_vec();
554        let attr_name = if let &[path_start, attr_name] = path.as_slice()
555            && (path_start == "charon" || path_start == "aeneas" || path_start == "verify")
556        {
557            attr_name
558        } else {
559            return Ok(Attribute::Unknown(raw_attr));
560        };
561
562        match self.parse_special_attr(def_id, attr_name, &raw_attr)? {
563            Some(parsed) => Ok(parsed),
564            None => Err(format!(
565                "Unrecognized attribute: `{}`",
566                raw_attr.to_string()
567            )),
568        }
569    }
570
571    /// Parse a `charon::*`, `aeneas::*` or `verify::*` attribute.
572    fn parse_special_attr(
573        &mut self,
574        def_id: &hax::DefId,
575        attr_name: &str,
576        raw_attr: &RawAttribute,
577    ) -> Result<Option<Attribute>, String> {
578        let args = raw_attr.args.as_deref();
579        let parsed = match attr_name {
580            // `#[charon::opaque]`
581            "opaque" if args.is_none() => Attribute::Opaque,
582            // `#[charon::opaque]`
583            "exclude" if args.is_none() => Attribute::Exclude,
584            // `#[charon::rename("new_name")]`
585            "rename" if let Some(attr) = args => {
586                let Some(attr) = attr
587                    .strip_prefix("\"")
588                    .and_then(|attr| attr.strip_suffix("\""))
589                else {
590                    return Err(format!(
591                        "the new name should be between quotes: `rename(\"{attr}\")`."
592                    ));
593                };
594
595                if attr.is_empty() {
596                    return Err(format!("attribute `rename` should not be empty"));
597                }
598
599                let first_char = attr.chars().nth(0).unwrap();
600                let is_identifier = (first_char.is_alphabetic() || first_char == '_')
601                    && attr.chars().all(|c| c.is_alphanumeric() || c == '_');
602                if !is_identifier {
603                    return Err(format!(
604                        "attribute `rename` should contain a valid identifier"
605                    ));
606                }
607
608                Attribute::Rename(attr.to_string())
609            }
610            // `#[charon::variants_prefix("T")]`
611            "variants_prefix" if let Some(attr) = args => {
612                let Some(attr) = attr
613                    .strip_prefix("\"")
614                    .and_then(|attr| attr.strip_suffix("\""))
615                else {
616                    return Err(format!(
617                        "the name should be between quotes: `variants_prefix(\"{attr}\")`."
618                    ));
619                };
620
621                Attribute::VariantsPrefix(attr.to_string())
622            }
623            // `#[charon::variants_suffix("T")]`
624            "variants_suffix" if let Some(attr) = args => {
625                let Some(attr) = attr
626                    .strip_prefix("\"")
627                    .and_then(|attr| attr.strip_suffix("\""))
628                else {
629                    return Err(format!(
630                        "the name should be between quotes: `variants_suffix(\"{attr}\")`."
631                    ));
632                };
633
634                Attribute::VariantsSuffix(attr.to_string())
635            }
636            // `#[verify::start_from]`
637            "start_from" => {
638                if matches!(def_id.kind, hax::DefKind::Mod) {
639                    return Err(format!("`start_from` on modules has no effect"));
640                }
641                Attribute::Unknown(raw_attr.clone())
642            }
643            // `#[verify::test]`: mark a function for test extraction
644            "test" if args.is_none() => Attribute::Unknown(raw_attr.clone()),
645            _ => return Ok(None),
646        };
647        Ok(Some(parsed))
648    }
649
650    /// Translates a rust attribute. Returns `None` if the attribute is a doc comment (rustc
651    /// encodes them as attributes). For now we use `String`s for `Attributes`.
652    pub(crate) fn translate_attribute(
653        &mut self,
654        def_id: &hax::DefId,
655        attr: &rustc_hir::Attribute,
656    ) -> Option<Attribute> {
657        use rustc_hir as hir;
658        use rustc_hir::attrs as hir_attrs;
659        match attr {
660            hir::Attribute::Parsed(hir_attrs::AttributeKind::DocComment { comment, .. }) => {
661                Some(Attribute::DocComment(comment.to_string()))
662            }
663            hir::Attribute::Parsed(_) => None,
664            hir::Attribute::Unparsed(attr) => {
665                let raw_attr = RawAttribute {
666                    path: attr.path.to_string(),
667                    args: match &attr.args {
668                        hir::AttrArgs::Empty => None,
669                        hir::AttrArgs::Delimited(args) => {
670                            Some(rustc_ast_pretty::pprust::tts_to_string(&args.tokens))
671                        }
672                        hir::AttrArgs::Eq { expr, .. } => {
673                            self.tcx.sess.source_map().span_to_snippet(expr.span).ok()
674                        }
675                    },
676                };
677                match self.parse_attr_from_raw(def_id, raw_attr) {
678                    Ok(a) => Some(a),
679                    Err(msg) => {
680                        let span = self.translate_span(&attr.span.sinto(&self.hax_state));
681                        register_error!(self, span, "Error parsing attribute: {msg}");
682                        None
683                    }
684                }
685            }
686        }
687    }
688
689    pub(crate) fn translate_inline(&self, def: &hax::FullDef) -> Option<InlineAttr> {
690        match def.kind() {
691            hax::FullDefKind::Fn { inline, .. }
692            | hax::FullDefKind::AssocFn { inline, .. }
693            | hax::FullDefKind::Closure { inline, .. } => match inline {
694                hax::InlineAttr::None => None,
695                hax::InlineAttr::Hint => Some(InlineAttr::Hint),
696                hax::InlineAttr::Never => Some(InlineAttr::Never),
697                hax::InlineAttr::Always => Some(InlineAttr::Always),
698                hax::InlineAttr::Force { .. } => Some(InlineAttr::Always),
699            },
700            _ => None,
701        }
702    }
703
704    pub(crate) fn translate_attr_info(&mut self, def: &hax::FullDef) -> AttrInfo {
705        // Default to `false` for impl blocks and closures.
706        let public = def.visibility.unwrap_or(false);
707        let inline = self.translate_inline(def);
708        let attributes = def
709            .attributes
710            .iter()
711            .filter_map(|attr| self.translate_attribute(def.def_id(), &attr))
712            .collect_vec();
713
714        let rename = {
715            let mut renames = attributes.iter().filter_map(|a| a.as_rename()).cloned();
716            let rename = renames.next();
717            if renames.next().is_some() {
718                let span = self.translate_span(&def.span);
719                register_error!(
720                    self,
721                    span,
722                    "There should be at most one `charon::rename(\"...\")` \
723                    or `aeneas::rename(\"...\")` attribute per declaration",
724                );
725            }
726            rename
727        };
728
729        AttrInfo {
730            attributes,
731            inline,
732            public,
733            rename,
734        }
735    }
736}
737
738// `ItemMeta`
739impl<'tcx, 'ctx> TranslateCtx<'tcx> {
740    /// Whether this item is in an `extern { .. }` block, in which case it has no body.
741    pub(crate) fn is_extern_item(&mut self, def: &hax::FullDef) -> bool {
742        def.def_id()
743            .parent(&self.hax_state)
744            .is_some_and(|parent| matches!(parent.kind, hax::DefKind::ForeignMod { .. }))
745    }
746
747    /// Compute the meta information for a Rust item.
748    pub(crate) fn translate_item_meta(
749        &mut self,
750        def: &hax::FullDef,
751        item_src: &TransItemSource,
752        name: Name,
753        name_opacity: ItemOpacity,
754    ) -> ItemMeta {
755        if let Some(item_meta) = self.cached_item_metas.get(&item_src) {
756            return item_meta.clone();
757        }
758        let span = def.source_span.as_ref().unwrap_or(&def.span);
759        let span = self.translate_span(span);
760        let is_local = def.def_id().is_local();
761        let (attr_info, lang_item) = if !item_src.is_derived_item()
762            || matches!(item_src.kind, TransItemSourceKind::ClosureMethod(..))
763        {
764            let attr_info = self.translate_attr_info(def);
765            let lang_item = def
766                .lang_item
767                .clone()
768                .or_else(|| def.diagnostic_item.clone())
769                .map(|s| s.to_string());
770            (attr_info, lang_item)
771        } else {
772            (AttrInfo::default(), None)
773        };
774
775        let opacity = if attr_info.attributes.iter().any(|attr| attr.is_exclude()) {
776            ItemOpacity::Invisible.max(name_opacity)
777        } else if self.is_extern_item(def)
778            || attr_info.attributes.iter().any(|attr| attr.is_opaque())
779        {
780            // Force opaque in these cases.
781            ItemOpacity::Opaque.max(name_opacity)
782        } else {
783            name_opacity
784        };
785
786        let item_meta = ItemMeta {
787            name,
788            span,
789            source_text: def.source_text.clone(),
790            attr_info,
791            is_local,
792            opacity,
793            lang_item,
794        };
795        self.cached_item_metas
796            .insert(item_src.clone(), item_meta.clone());
797        item_meta
798    }
799}
charon_driver/translate/translate_meta.rs

charon_driver/translate/
translate_meta.rs
