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};
45 pub mod codegen_attrs;
54 pub mod target_features;
57 pub struct ModuleCodegen<M> {
58 /// The name of the module. When the crate may be saved between
59 /// compilations, incremental compilation requires that name be
60 /// unique amongst **all** crates. Therefore, it should contain
61 /// something unique to this crate (e.g., a module path) as well
62 /// as the crate name and disambiguator.
63 /// We currently generate these names via CodegenUnit::build_cgu_name().
69 impl<M> ModuleCodegen<M> {
70 pub fn into_compiled_module(
75 outputs: &OutputFilenames,
77 let object = emit_obj.then(|| outputs.temp_path(OutputType::Object, Some(&self.name)));
78 let dwarf_object = emit_dwarf_obj.then(|| outputs.temp_path_dwo(Some(&self.name)));
79 let bytecode = emit_bc.then(|| outputs.temp_path(OutputType::Bitcode, Some(&self.name)));
81 CompiledModule { name: self.name.clone(), kind: self.kind, object, dwarf_object, bytecode }
85 #[derive(Debug, Encodable, Decodable)]
86 pub struct CompiledModule {
89 pub object: Option<PathBuf>,
90 pub dwarf_object: Option<PathBuf>,
91 pub bytecode: Option<PathBuf>,
94 pub struct CachedModuleCodegen {
96 pub source: WorkProduct,
99 #[derive(Copy, Clone, Debug, PartialEq, Encodable, Decodable)]
100 pub enum ModuleKind {
106 bitflags::bitflags! {
107 pub struct MemFlags: u8 {
108 const VOLATILE = 1 << 0;
109 const NONTEMPORAL = 1 << 1;
110 const UNALIGNED = 1 << 2;
114 #[derive(Clone, Debug, Encodable, Decodable, HashStable)]
115 pub struct NativeLib {
116 pub kind: NativeLibKind,
117 pub name: Option<Symbol>,
118 pub filename: Option<Symbol>,
119 pub cfg: Option<ast::MetaItem>,
121 pub dll_imports: Vec<cstore::DllImport>,
124 impl From<&cstore::NativeLib> for NativeLib {
125 fn from(lib: &cstore::NativeLib) -> Self {
128 filename: lib.filename,
130 cfg: lib.cfg.clone(),
131 verbatim: lib.verbatim.unwrap_or(false),
132 dll_imports: lib.dll_imports.clone(),
137 /// Misc info we load from metadata to persist beyond the tcx.
139 /// Note: though `CrateNum` is only meaningful within the same tcx, information within `CrateInfo`
140 /// is self-contained. `CrateNum` can be viewed as a unique identifier within a `CrateInfo`, where
141 /// `used_crate_source` contains all `CrateSource` of the dependents, and maintains a mapping from
142 /// identifiers (`CrateNum`) to `CrateSource`. The other fields map `CrateNum` to the crate's own
143 /// additional properties, so that effectively we can retrieve each dependent crate's `CrateSource`
144 /// and the corresponding properties without referencing information outside of a `CrateInfo`.
145 #[derive(Debug, Encodable, Decodable)]
146 pub struct CrateInfo {
147 pub target_cpu: String,
148 pub exported_symbols: FxHashMap<CrateType, Vec<String>>,
149 pub linked_symbols: FxHashMap<CrateType, Vec<(String, SymbolExportKind)>>,
150 pub local_crate_name: Symbol,
151 pub compiler_builtins: Option<CrateNum>,
152 pub profiler_runtime: Option<CrateNum>,
153 pub is_no_builtins: FxHashSet<CrateNum>,
154 pub native_libraries: FxHashMap<CrateNum, Vec<NativeLib>>,
155 pub crate_name: FxHashMap<CrateNum, Symbol>,
156 pub used_libraries: Vec<NativeLib>,
157 pub used_crate_source: FxHashMap<CrateNum, Lrc<CrateSource>>,
158 pub used_crates: Vec<CrateNum>,
159 pub dependency_formats: Lrc<Dependencies>,
160 pub windows_subsystem: Option<String>,
161 pub natvis_debugger_visualizers: BTreeSet<DebuggerVisualizerFile>,
164 #[derive(Encodable, Decodable)]
165 pub struct CodegenResults {
166 pub modules: Vec<CompiledModule>,
167 pub allocator_module: Option<CompiledModule>,
168 pub metadata_module: Option<CompiledModule>,
169 pub metadata: rustc_metadata::EncodedMetadata,
170 pub crate_info: CrateInfo,
173 pub enum CodegenErrors<'a> {
176 EncodingVersionMismatch { version_array: String, rlink_version: u32 },
177 RustcVersionMismatch { rustc_version: String, current_version: &'a str },
180 pub fn provide(providers: &mut Providers) {
181 crate::back::symbol_export::provide(providers);
182 crate::base::provide(providers);
183 crate::target_features::provide(providers);
184 crate::codegen_attrs::provide(providers);
187 pub fn provide_extern(providers: &mut ExternProviders) {
188 crate::back::symbol_export::provide_extern(providers);
191 /// Checks if the given filename ends with the `.rcgu.o` extension that `rustc`
192 /// uses for the object files it generates.
193 pub fn looks_like_rust_object_file(filename: &str) -> bool {
194 let path = Path::new(filename);
195 let ext = path.extension().and_then(|s| s.to_str());
196 if ext != Some(OutputType::Object.extension()) {
197 // The file name does not end with ".o", so it can't be an object file.
201 // Strip the ".o" at the end
202 let ext2 = path.file_stem().and_then(|s| Path::new(s).extension()).and_then(|s| s.to_str());
204 // Check if the "inner" extension
205 ext2 == Some(RUST_CGU_EXT)
208 const RLINK_VERSION: u32 = 1;
209 const RLINK_MAGIC: &[u8] = b"rustlink";
211 const RUSTC_VERSION: Option<&str> = option_env!("CFG_VERSION");
213 impl CodegenResults {
214 pub fn serialize_rlink(codegen_results: &CodegenResults) -> Vec<u8> {
215 let mut encoder = MemEncoder::new();
216 encoder.emit_raw_bytes(RLINK_MAGIC);
217 // `emit_raw_bytes` is used to make sure that the version representation does not depend on
218 // Encoder's inner representation of `u32`.
219 encoder.emit_raw_bytes(&RLINK_VERSION.to_be_bytes());
220 encoder.emit_str(RUSTC_VERSION.unwrap());
221 Encodable::encode(codegen_results, &mut encoder);
225 pub fn deserialize_rlink<'a>(data: Vec<u8>) -> Result<Self, CodegenErrors<'a>> {
226 // The Decodable machinery is not used here because it panics if the input data is invalid
227 // and because its internal representation may change.
228 if !data.starts_with(RLINK_MAGIC) {
229 return Err(CodegenErrors::WrongFileType);
231 let data = &data[RLINK_MAGIC.len()..];
233 return Err(CodegenErrors::EmptyVersionNumber);
236 let mut version_array: [u8; 4] = Default::default();
237 version_array.copy_from_slice(&data[..4]);
238 if u32::from_be_bytes(version_array) != RLINK_VERSION {
239 return Err(CodegenErrors::EncodingVersionMismatch {
240 version_array: String::from_utf8_lossy(&version_array).to_string(),
241 rlink_version: RLINK_VERSION,
245 let mut decoder = MemDecoder::new(&data[4..], 0);
246 let rustc_version = decoder.read_str();
247 let current_version = RUSTC_VERSION.unwrap();
248 if rustc_version != current_version {
249 return Err(CodegenErrors::RustcVersionMismatch {
250 rustc_version: rustc_version.to_string(),
255 let codegen_results = CodegenResults::decode(&mut decoder);