1 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
2 #![feature(associated_type_bounds)]
3 #![feature(box_patterns)]
4 #![feature(if_let_guard)]
5 #![feature(int_roundings)]
6 #![feature(let_chains)]
7 #![feature(never_type)]
9 #![feature(strict_provenance)]
10 #![feature(try_blocks)]
11 #![recursion_limit = "256"]
12 #![allow(rustc::potential_query_instability)]
14 //! This crate contains codegen code that is used by all codegen backends (LLVM and others).
15 //! The backend-agnostic functions of this crate use functions defined in various traits that
16 //! have to be implemented by each backends.
19 extern crate rustc_macros;
23 extern crate rustc_middle;
26 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
27 use rustc_data_structures::sync::Lrc;
28 use rustc_hir::def_id::CrateNum;
29 use rustc_middle::dep_graph::WorkProduct;
30 use rustc_middle::middle::dependency_format::Dependencies;
31 use rustc_middle::middle::exported_symbols::SymbolExportKind;
32 use rustc_middle::ty::query::{ExternProviders, Providers};
33 use rustc_serialize::opaque::{MemDecoder, MemEncoder};
34 use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
35 use rustc_session::config::{CrateType, OutputFilenames, OutputType, RUST_CGU_EXT};
36 use rustc_session::cstore::{self, CrateSource};
37 use rustc_session::utils::NativeLibKind;
38 use rustc_span::symbol::Symbol;
39 use rustc_span::DebuggerVisualizerFile;
40 use std::collections::BTreeSet;
41 use std::path::{Path, PathBuf};
53 pub mod target_features;
56 pub struct ModuleCodegen<M> {
57 /// The name of the module. When the crate may be saved between
58 /// compilations, incremental compilation requires that name be
59 /// unique amongst **all** crates. Therefore, it should contain
60 /// something unique to this crate (e.g., a module path) as well
61 /// as the crate name and disambiguator.
62 /// We currently generate these names via CodegenUnit::build_cgu_name().
68 impl<M> ModuleCodegen<M> {
69 pub fn into_compiled_module(
74 outputs: &OutputFilenames,
76 let object = emit_obj.then(|| outputs.temp_path(OutputType::Object, Some(&self.name)));
77 let dwarf_object = emit_dwarf_obj.then(|| outputs.temp_path_dwo(Some(&self.name)));
78 let bytecode = emit_bc.then(|| outputs.temp_path(OutputType::Bitcode, Some(&self.name)));
80 CompiledModule { name: self.name.clone(), kind: self.kind, object, dwarf_object, bytecode }
84 #[derive(Debug, Encodable, Decodable)]
85 pub struct CompiledModule {
88 pub object: Option<PathBuf>,
89 pub dwarf_object: Option<PathBuf>,
90 pub bytecode: Option<PathBuf>,
93 pub struct CachedModuleCodegen {
95 pub source: WorkProduct,
98 #[derive(Copy, Clone, Debug, PartialEq, Encodable, Decodable)]
105 bitflags::bitflags! {
106 pub struct MemFlags: u8 {
107 const VOLATILE = 1 << 0;
108 const NONTEMPORAL = 1 << 1;
109 const UNALIGNED = 1 << 2;
113 #[derive(Clone, Debug, Encodable, Decodable, HashStable)]
114 pub struct NativeLib {
115 pub kind: NativeLibKind,
116 pub name: Option<Symbol>,
117 pub filename: Option<Symbol>,
118 pub cfg: Option<ast::MetaItem>,
120 pub dll_imports: Vec<cstore::DllImport>,
123 impl From<&cstore::NativeLib> for NativeLib {
124 fn from(lib: &cstore::NativeLib) -> Self {
127 filename: lib.filename,
129 cfg: lib.cfg.clone(),
130 verbatim: lib.verbatim.unwrap_or(false),
131 dll_imports: lib.dll_imports.clone(),
136 /// Misc info we load from metadata to persist beyond the tcx.
138 /// Note: though `CrateNum` is only meaningful within the same tcx, information within `CrateInfo`
139 /// is self-contained. `CrateNum` can be viewed as a unique identifier within a `CrateInfo`, where
140 /// `used_crate_source` contains all `CrateSource` of the dependents, and maintains a mapping from
141 /// identifiers (`CrateNum`) to `CrateSource`. The other fields map `CrateNum` to the crate's own
142 /// additional properties, so that effectively we can retrieve each dependent crate's `CrateSource`
143 /// and the corresponding properties without referencing information outside of a `CrateInfo`.
144 #[derive(Debug, Encodable, Decodable)]
145 pub struct CrateInfo {
146 pub target_cpu: String,
147 pub exported_symbols: FxHashMap<CrateType, Vec<String>>,
148 pub linked_symbols: FxHashMap<CrateType, Vec<(String, SymbolExportKind)>>,
149 pub local_crate_name: Symbol,
150 pub compiler_builtins: Option<CrateNum>,
151 pub profiler_runtime: Option<CrateNum>,
152 pub is_no_builtins: FxHashSet<CrateNum>,
153 pub native_libraries: FxHashMap<CrateNum, Vec<NativeLib>>,
154 pub crate_name: FxHashMap<CrateNum, Symbol>,
155 pub used_libraries: Vec<NativeLib>,
156 pub used_crate_source: FxHashMap<CrateNum, Lrc<CrateSource>>,
157 pub used_crates: Vec<CrateNum>,
158 pub dependency_formats: Lrc<Dependencies>,
159 pub windows_subsystem: Option<String>,
160 pub natvis_debugger_visualizers: BTreeSet<DebuggerVisualizerFile>,
163 #[derive(Encodable, Decodable)]
164 pub struct CodegenResults {
165 pub modules: Vec<CompiledModule>,
166 pub allocator_module: Option<CompiledModule>,
167 pub metadata_module: Option<CompiledModule>,
168 pub metadata: rustc_metadata::EncodedMetadata,
169 pub crate_info: CrateInfo,
172 pub enum CodegenErrors<'a> {
175 EncodingVersionMismatch { version_array: String, rlink_version: u32 },
176 RustcVersionMismatch { rustc_version: String, current_version: &'a str },
179 pub fn provide(providers: &mut Providers) {
180 crate::back::symbol_export::provide(providers);
181 crate::base::provide(providers);
182 crate::target_features::provide(providers);
185 pub fn provide_extern(providers: &mut ExternProviders) {
186 crate::back::symbol_export::provide_extern(providers);
189 /// Checks if the given filename ends with the `.rcgu.o` extension that `rustc`
190 /// uses for the object files it generates.
191 pub fn looks_like_rust_object_file(filename: &str) -> bool {
192 let path = Path::new(filename);
193 let ext = path.extension().and_then(|s| s.to_str());
194 if ext != Some(OutputType::Object.extension()) {
195 // The file name does not end with ".o", so it can't be an object file.
199 // Strip the ".o" at the end
200 let ext2 = path.file_stem().and_then(|s| Path::new(s).extension()).and_then(|s| s.to_str());
202 // Check if the "inner" extension
203 ext2 == Some(RUST_CGU_EXT)
206 const RLINK_VERSION: u32 = 1;
207 const RLINK_MAGIC: &[u8] = b"rustlink";
209 const RUSTC_VERSION: Option<&str> = option_env!("CFG_VERSION");
211 impl CodegenResults {
212 pub fn serialize_rlink(codegen_results: &CodegenResults) -> Vec<u8> {
213 let mut encoder = MemEncoder::new();
214 encoder.emit_raw_bytes(RLINK_MAGIC);
215 // `emit_raw_bytes` is used to make sure that the version representation does not depend on
216 // Encoder's inner representation of `u32`.
217 encoder.emit_raw_bytes(&RLINK_VERSION.to_be_bytes());
218 encoder.emit_str(RUSTC_VERSION.unwrap());
219 Encodable::encode(codegen_results, &mut encoder);
223 pub fn deserialize_rlink<'a>(data: Vec<u8>) -> Result<Self, CodegenErrors<'a>> {
224 // The Decodable machinery is not used here because it panics if the input data is invalid
225 // and because its internal representation may change.
226 if !data.starts_with(RLINK_MAGIC) {
227 return Err(CodegenErrors::WrongFileType);
229 let data = &data[RLINK_MAGIC.len()..];
231 return Err(CodegenErrors::EmptyVersionNumber);
234 let mut version_array: [u8; 4] = Default::default();
235 version_array.copy_from_slice(&data[..4]);
236 if u32::from_be_bytes(version_array) != RLINK_VERSION {
237 return Err(CodegenErrors::EncodingVersionMismatch {
238 version_array: String::from_utf8_lossy(&version_array).to_string(),
239 rlink_version: RLINK_VERSION,
243 let mut decoder = MemDecoder::new(&data[4..], 0);
244 let rustc_version = decoder.read_str();
245 let current_version = RUSTC_VERSION.unwrap();
246 if rustc_version != current_version {
247 return Err(CodegenErrors::RustcVersionMismatch {
248 rustc_version: rustc_version.to_string(),
253 let codegen_results = CodegenResults::decode(&mut decoder);