src/librustc_metadata/cstore.rs

   1 // Copyright 2012-2014 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.
   4 //
   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.
  10
  11 // The crate store - a central repo for information collected about external
  12 // crates and libraries
  13
  14 use locator;
  15 use schema;
  16
  17 use rustc::dep_graph::DepGraph;
  18 use rustc::hir::def_id::{CRATE_DEF_INDEX, LOCAL_CRATE, CrateNum, DefIndex, DefId};
  19 use rustc::hir::map::definitions::DefPathTable;
  20 use rustc::hir::svh::Svh;
  21 use rustc::middle::cstore::{DepKind, ExternCrate};
  22 use rustc_back::PanicStrategy;
  23 use rustc_data_structures::indexed_vec::IndexVec;
  24 use rustc::util::nodemap::{FxHashMap, FxHashSet, NodeMap, DefIdMap};
  25
  26 use std::cell::{RefCell, Cell};
  27 use std::rc::Rc;
  28 use flate::Bytes;
  29 use syntax::{ast, attr};
  30 use syntax::ext::base::SyntaxExtension;
  31 use syntax::symbol::Symbol;
  32 use syntax_pos;
  33
  34 pub use rustc::middle::cstore::{NativeLibrary, NativeLibraryKind, LinkagePreference};
  35 pub use rustc::middle::cstore::NativeLibraryKind::*;
  36 pub use rustc::middle::cstore::{CrateSource, LinkMeta, LibSource};
  37
  38 pub use cstore_impl::provide;
  39
  40 // A map from external crate numbers (as decoded from some crate file) to
  41 // local crate numbers (as generated during this session). Each external
  42 // crate may refer to types in other external crates, and each has their
  43 // own crate numbers.
  44 pub type CrateNumMap = IndexVec<CrateNum, CrateNum>;
  45
  46 pub enum MetadataBlob {
  47     Inflated(Bytes),
  48     Archive(locator::ArchiveMetadata),
  49     Raw(Vec<u8>),
  50 }
  51
  52 /// Holds information about a syntax_pos::FileMap imported from another crate.
  53 /// See `imported_filemaps()` for more information.
  54 pub struct ImportedFileMap {
  55     /// This FileMap's byte-offset within the codemap of its original crate
  56     pub original_start_pos: syntax_pos::BytePos,
  57     /// The end of this FileMap within the codemap of its original crate
  58     pub original_end_pos: syntax_pos::BytePos,
  59     /// The imported FileMap's representation within the local codemap
  60     pub translated_filemap: Rc<syntax_pos::FileMap>,
  61 }
  62
  63 pub struct CrateMetadata {
  64     pub name: Symbol,
  65
  66     /// Information about the extern crate that caused this crate to
  67     /// be loaded. If this is `None`, then the crate was injected
  68     /// (e.g., by the allocator)
  69     pub extern_crate: Cell<Option<ExternCrate>>,
  70
  71     pub blob: MetadataBlob,
  72     pub cnum_map: RefCell<CrateNumMap>,
  73     pub cnum: CrateNum,
  74     pub codemap_import_info: RefCell<Vec<ImportedFileMap>>,
  75
  76     pub root: schema::CrateRoot,
  77
  78     /// For each public item in this crate, we encode a key.  When the
  79     /// crate is loaded, we read all the keys and put them in this
  80     /// hashmap, which gives the reverse mapping.  This allows us to
  81     /// quickly retrace a `DefPath`, which is needed for incremental
  82     /// compilation support.
  83     pub def_path_table: DefPathTable,
  84
  85     pub exported_symbols: FxHashSet<DefIndex>,
  86
  87     pub dep_kind: Cell<DepKind>,
  88     pub source: CrateSource,
  89
  90     pub proc_macros: Option<Vec<(ast::Name, Rc<SyntaxExtension>)>>,
  91     // Foreign items imported from a dylib (Windows only)
  92     pub dllimport_foreign_items: FxHashSet<DefIndex>,
  93 }
  94
  95 pub struct CStore {
  96     pub dep_graph: DepGraph,
  97     metas: RefCell<FxHashMap<CrateNum, Rc<CrateMetadata>>>,
  98     /// Map from NodeId's of local extern crate statements to crate numbers
  99     extern_mod_crate_map: RefCell<NodeMap<CrateNum>>,
 100     used_libraries: RefCell<Vec<NativeLibrary>>,
 101     used_link_args: RefCell<Vec<String>>,
 102     statically_included_foreign_items: RefCell<FxHashSet<DefIndex>>,
 103     pub dllimport_foreign_items: RefCell<FxHashSet<DefIndex>>,
 104     pub visible_parent_map: RefCell<DefIdMap<DefId>>,
 105 }
 106
 107 impl CStore {
 108     pub fn new(dep_graph: &DepGraph) -> CStore {
 109         CStore {
 110             dep_graph: dep_graph.clone(),
 111             metas: RefCell::new(FxHashMap()),
 112             extern_mod_crate_map: RefCell::new(FxHashMap()),
 113             used_libraries: RefCell::new(Vec::new()),
 114             used_link_args: RefCell::new(Vec::new()),
 115             statically_included_foreign_items: RefCell::new(FxHashSet()),
 116             dllimport_foreign_items: RefCell::new(FxHashSet()),
 117             visible_parent_map: RefCell::new(FxHashMap()),
 118         }
 119     }
 120
 121     pub fn next_crate_num(&self) -> CrateNum {
 122         CrateNum::new(self.metas.borrow().len() + 1)
 123     }
 124
 125     pub fn get_crate_data(&self, cnum: CrateNum) -> Rc<CrateMetadata> {
 126         self.metas.borrow().get(&cnum).unwrap().clone()
 127     }
 128
 129     pub fn get_crate_hash(&self, cnum: CrateNum) -> Svh {
 130         self.get_crate_data(cnum).hash()
 131     }
 132
 133     pub fn set_crate_data(&self, cnum: CrateNum, data: Rc<CrateMetadata>) {
 134         self.metas.borrow_mut().insert(cnum, data);
 135     }
 136
 137     pub fn iter_crate_data<I>(&self, mut i: I)
 138         where I: FnMut(CrateNum, &Rc<CrateMetadata>)
 139     {
 140         for (&k, v) in self.metas.borrow().iter() {
 141             i(k, v);
 142         }
 143     }
 144
 145     pub fn reset(&self) {
 146         self.metas.borrow_mut().clear();
 147         self.extern_mod_crate_map.borrow_mut().clear();
 148         self.used_libraries.borrow_mut().clear();
 149         self.used_link_args.borrow_mut().clear();
 150         self.statically_included_foreign_items.borrow_mut().clear();
 151     }
 152
 153     pub fn crate_dependencies_in_rpo(&self, krate: CrateNum) -> Vec<CrateNum> {
 154         let mut ordering = Vec::new();
 155         self.push_dependencies_in_postorder(&mut ordering, krate);
 156         ordering.reverse();
 157         ordering
 158     }
 159
 160     pub fn push_dependencies_in_postorder(&self, ordering: &mut Vec<CrateNum>, krate: CrateNum) {
 161         if ordering.contains(&krate) {
 162             return;
 163         }
 164
 165         let data = self.get_crate_data(krate);
 166         for &dep in data.cnum_map.borrow().iter() {
 167             if dep != krate {
 168                 self.push_dependencies_in_postorder(ordering, dep);
 169             }
 170         }
 171
 172         ordering.push(krate);
 173     }
 174
 175     // This method is used when generating the command line to pass through to
 176     // system linker. The linker expects undefined symbols on the left of the
 177     // command line to be defined in libraries on the right, not the other way
 178     // around. For more info, see some comments in the add_used_library function
 179     // below.
 180     //
 181     // In order to get this left-to-right dependency ordering, we perform a
 182     // topological sort of all crates putting the leaves at the right-most
 183     // positions.
 184     pub fn do_get_used_crates(&self,
 185                               prefer: LinkagePreference)
 186                               -> Vec<(CrateNum, LibSource)> {
 187         let mut ordering = Vec::new();
 188         for (&num, _) in self.metas.borrow().iter() {
 189             self.push_dependencies_in_postorder(&mut ordering, num);
 190         }
 191         info!("topological ordering: {:?}", ordering);
 192         ordering.reverse();
 193         let mut libs = self.metas
 194             .borrow()
 195             .iter()
 196             .filter_map(|(&cnum, data)| {
 197                 if data.dep_kind.get().macros_only() { return None; }
 198                 let path = match prefer {
 199                     LinkagePreference::RequireDynamic => data.source.dylib.clone().map(|p| p.0),
 200                     LinkagePreference::RequireStatic => data.source.rlib.clone().map(|p| p.0),
 201                 };
 202                 let path = match path {
 203                     Some(p) => LibSource::Some(p),
 204                     None => {
 205                         if data.source.rmeta.is_some() {
 206                             LibSource::MetadataOnly
 207                         } else {
 208                             LibSource::None
 209                         }
 210                     }
 211                 };
 212                 Some((cnum, path))
 213             })
 214             .collect::<Vec<_>>();
 215         libs.sort_by(|&(a, _), &(b, _)| {
 216             let a = ordering.iter().position(|x| *x == a);
 217             let b = ordering.iter().position(|x| *x == b);
 218             a.cmp(&b)
 219         });
 220         libs
 221     }
 222
 223     pub fn add_used_library(&self, lib: NativeLibrary) {
 224         assert!(!lib.name.as_str().is_empty());
 225         self.used_libraries.borrow_mut().push(lib);
 226     }
 227
 228     pub fn get_used_libraries(&self) -> &RefCell<Vec<NativeLibrary>> {
 229         &self.used_libraries
 230     }
 231
 232     pub fn add_used_link_args(&self, args: &str) {
 233         for s in args.split(' ').filter(|s| !s.is_empty()) {
 234             self.used_link_args.borrow_mut().push(s.to_string());
 235         }
 236     }
 237
 238     pub fn get_used_link_args<'a>(&'a self) -> &'a RefCell<Vec<String>> {
 239         &self.used_link_args
 240     }
 241
 242     pub fn add_extern_mod_stmt_cnum(&self, emod_id: ast::NodeId, cnum: CrateNum) {
 243         self.extern_mod_crate_map.borrow_mut().insert(emod_id, cnum);
 244     }
 245
 246     pub fn add_statically_included_foreign_item(&self, id: DefIndex) {
 247         self.statically_included_foreign_items.borrow_mut().insert(id);
 248     }
 249
 250     pub fn do_is_statically_included_foreign_item(&self, def_id: DefId) -> bool {
 251         assert!(def_id.krate == LOCAL_CRATE);
 252         self.statically_included_foreign_items.borrow().contains(&def_id.index)
 253     }
 254
 255     pub fn do_extern_mod_stmt_cnum(&self, emod_id: ast::NodeId) -> Option<CrateNum> {
 256         self.extern_mod_crate_map.borrow().get(&emod_id).cloned()
 257     }
 258 }
 259
 260 impl CrateMetadata {
 261     pub fn name(&self) -> Symbol {
 262         self.root.name
 263     }
 264     pub fn hash(&self) -> Svh {
 265         self.root.hash
 266     }
 267     pub fn disambiguator(&self) -> Symbol {
 268         self.root.disambiguator
 269     }
 270
 271     pub fn is_staged_api(&self) -> bool {
 272         self.get_item_attrs(CRATE_DEF_INDEX)
 273             .iter()
 274             .any(|attr| attr.name() == "stable" || attr.name() == "unstable")
 275     }
 276
 277     pub fn is_allocator(&self) -> bool {
 278         let attrs = self.get_item_attrs(CRATE_DEF_INDEX);
 279         attr::contains_name(&attrs, "allocator")
 280     }
 281
 282     pub fn needs_allocator(&self) -> bool {
 283         let attrs = self.get_item_attrs(CRATE_DEF_INDEX);
 284         attr::contains_name(&attrs, "needs_allocator")
 285     }
 286
 287     pub fn is_panic_runtime(&self) -> bool {
 288         let attrs = self.get_item_attrs(CRATE_DEF_INDEX);
 289         attr::contains_name(&attrs, "panic_runtime")
 290     }
 291
 292     pub fn needs_panic_runtime(&self) -> bool {
 293         let attrs = self.get_item_attrs(CRATE_DEF_INDEX);
 294         attr::contains_name(&attrs, "needs_panic_runtime")
 295     }
 296
 297     pub fn is_compiler_builtins(&self) -> bool {
 298         let attrs = self.get_item_attrs(CRATE_DEF_INDEX);
 299         attr::contains_name(&attrs, "compiler_builtins")
 300     }
 301
 302     pub fn is_sanitizer_runtime(&self) -> bool {
 303         let attrs = self.get_item_attrs(CRATE_DEF_INDEX);
 304         attr::contains_name(&attrs, "sanitizer_runtime")
 305     }
 306
 307     pub fn is_no_builtins(&self) -> bool {
 308         let attrs = self.get_item_attrs(CRATE_DEF_INDEX);
 309         attr::contains_name(&attrs, "no_builtins")
 310     }
 311
 312     pub fn panic_strategy(&self) -> PanicStrategy {
 313         self.root.panic_strategy.clone()
 314     }
 315 }