user0/rust
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions
rust/compiler/rustc_metadata/src/rmeta/encoder.rs

2291 lines
92 KiB
Rust
Raw Blame History

use crate::errors::{FailCreateFileEncoder, FailSeekFile, FailWriteFile};
use crate::rmeta::def_path_hash_map::DefPathHashMapRef;
use crate::rmeta::table::TableBuilder;
use crate::rmeta::*;
use rustc_ast::Attribute;
use rustc_data_structures::fingerprint::Fingerprint;
use rustc_data_structures::fx::{FxHashMap, FxIndexSet};
use rustc_data_structures::memmap::{Mmap, MmapMut};
use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
use rustc_data_structures::sync::{join, par_iter, Lrc, ParallelIterator};
use rustc_data_structures::temp_dir::MaybeTempDir;
use rustc_hir as hir;
use rustc_hir::def::DefKind;
use rustc_hir::def_id::{
CrateNum, DefId, DefIndex, LocalDefId, CRATE_DEF_ID, CRATE_DEF_INDEX, LOCAL_CRATE,
};
use rustc_hir::definitions::DefPathData;
use rustc_hir::intravisit::{self, Visitor};
use rustc_hir::lang_items::LangItem;
use rustc_middle::hir::nested_filter;
use rustc_middle::middle::dependency_format::Linkage;
use rustc_middle::middle::exported_symbols::{
metadata_symbol_name, ExportedSymbol, SymbolExportInfo,
};
use rustc_middle::mir::interpret;
use rustc_middle::traits::specialization_graph;
use rustc_middle::ty::codec::TyEncoder;
use rustc_middle::ty::fast_reject::{self, SimplifiedType, TreatParams};
use rustc_middle::ty::query::Providers;
use rustc_middle::ty::{self, SymbolName, Ty, TyCtxt};
use rustc_middle::util::common::to_readable_str;
use rustc_serialize::{opaque, Decodable, Decoder, Encodable, Encoder};
use rustc_session::config::{CrateType, OptLevel};
use rustc_session::cstore::{ForeignModule, LinkagePreference, NativeLib};
use rustc_span::hygiene::{ExpnIndex, HygieneEncodeContext, MacroKind};
use rustc_span::symbol::{sym, Symbol};
use rustc_span::{
self, DebuggerVisualizerFile, ExternalSource, FileName, SourceFile, Span, SyntaxContext,
};
use rustc_target::abi::VariantIdx;
use std::borrow::Borrow;
use std::collections::hash_map::Entry;
use std::hash::Hash;
use std::io::{Read, Seek, Write};
use std::iter;
use std::num::NonZeroUsize;
use std::path::{Path, PathBuf};
pub(super) struct EncodeContext<'a, 'tcx> {
opaque: opaque::FileEncoder,
tcx: TyCtxt<'tcx>,
feat: &'tcx rustc_feature::Features,
tables: TableBuilders,
lazy_state: LazyState,
type_shorthands: FxHashMap<Ty<'tcx>, usize>,
predicate_shorthands: FxHashMap<ty::PredicateKind<'tcx>, usize>,
interpret_allocs: FxIndexSet<interpret::AllocId>,
// This is used to speed up Span encoding.
// The `usize` is an index into the `MonotonicVec`
// that stores the `SourceFile`
source_file_cache: (Lrc<SourceFile>, usize),
// The indices (into the `SourceMap`'s `MonotonicVec`)
// of all of the `SourceFiles` that we need to serialize.
// When we serialize a `Span`, we insert the index of its
// `SourceFile` into the `FxIndexSet`.
// The order inside the `FxIndexSet` is used as on-disk
// order of `SourceFiles`, and encoded inside `Span`s.
required_source_files: Option<FxIndexSet<usize>>,
is_proc_macro: bool,
hygiene_ctxt: &'a HygieneEncodeContext,
symbol_table: FxHashMap<Symbol, usize>,
}
/// If the current crate is a proc-macro, returns early with `Lazy:empty()`.
/// This is useful for skipping the encoding of things that aren't needed
/// for proc-macro crates.
macro_rules! empty_proc_macro {
($self:ident) => {
if $self.is_proc_macro {
return LazyArray::empty();
}
};
}
macro_rules! encoder_methods {
($($name:ident($ty:ty);)*) => {
$(fn $name(&mut self, value: $ty) {
self.opaque.$name(value)
})*
}
}
impl<'a, 'tcx> Encoder for EncodeContext<'a, 'tcx> {
encoder_methods! {
emit_usize(usize);
emit_u128(u128);
emit_u64(u64);
emit_u32(u32);
emit_u16(u16);
emit_u8(u8);
emit_isize(isize);
emit_i128(i128);
emit_i64(i64);
emit_i32(i32);
emit_i16(i16);
emit_i8(i8);
emit_bool(bool);
emit_f64(f64);
emit_f32(f32);
emit_char(char);
emit_str(&str);
emit_raw_bytes(&[u8]);
}
}
impl<'a, 'tcx, T> Encodable<EncodeContext<'a, 'tcx>> for LazyValue<T> {
fn encode(&self, e: &mut EncodeContext<'a, 'tcx>) {
e.emit_lazy_distance(self.position);
}
}
impl<'a, 'tcx, T> Encodable<EncodeContext<'a, 'tcx>> for LazyArray<T> {
fn encode(&self, e: &mut EncodeContext<'a, 'tcx>) {
e.emit_usize(self.num_elems);
if self.num_elems > 0 {
e.emit_lazy_distance(self.position)
}
}
}
impl<'a, 'tcx, I, T> Encodable<EncodeContext<'a, 'tcx>> for LazyTable<I, T> {
fn encode(&self, e: &mut EncodeContext<'a, 'tcx>) {
e.emit_usize(self.encoded_size);
e.emit_lazy_distance(self.position);
}
}
impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for CrateNum {
fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
if *self != LOCAL_CRATE && s.is_proc_macro {
panic!("Attempted to encode non-local CrateNum {:?} for proc-macro crate", self);
}
s.emit_u32(self.as_u32());
}
}
impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for DefIndex {
fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
s.emit_u32(self.as_u32());
}
}
impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for ExpnIndex {
fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
s.emit_u32(self.as_u32());
}
}
impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for SyntaxContext {
fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
rustc_span::hygiene::raw_encode_syntax_context(*self, &s.hygiene_ctxt, s);
}
}
impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for ExpnId {
fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
if self.krate == LOCAL_CRATE {
// We will only write details for local expansions. Non-local expansions will fetch
// data from the corresponding crate's metadata.
// FIXME(#43047) FIXME(#74731) We may eventually want to avoid relying on external
// metadata from proc-macro crates.
s.hygiene_ctxt.schedule_expn_data_for_encoding(*self);
}
self.krate.encode(s);
self.local_id.encode(s);
}
}
impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for Span {
fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
let span = self.data();
// Don't serialize any `SyntaxContext`s from a proc-macro crate,
// since we don't load proc-macro dependencies during serialization.
// This means that any hygiene information from macros used *within*
// a proc-macro crate (e.g. invoking a macro that expands to a proc-macro
// definition) will be lost.
//
// This can show up in two ways:
//
// 1. Any hygiene information associated with identifier of
// a proc macro (e.g. `#[proc_macro] pub fn $name`) will be lost.
// Since proc-macros can only be invoked from a different crate,
// real code should never need to care about this.
//
// 2. Using `Span::def_site` or `Span::mixed_site` will not
// include any hygiene information associated with the definition
// site. This means that a proc-macro cannot emit a `$crate`
// identifier which resolves to one of its dependencies,
// which also should never come up in practice.
//
// Additionally, this affects `Span::parent`, and any other
// span inspection APIs that would otherwise allow traversing
// the `SyntaxContexts` associated with a span.
//
// None of these user-visible effects should result in any
// cross-crate inconsistencies (getting one behavior in the same
// crate, and a different behavior in another crate) due to the
// limited surface that proc-macros can expose.
//
// IMPORTANT: If this is ever changed, be sure to update
// `rustc_span::hygiene::raw_encode_expn_id` to handle
// encoding `ExpnData` for proc-macro crates.
if s.is_proc_macro {
SyntaxContext::root().encode(s);
} else {
span.ctxt.encode(s);
}
if self.is_dummy() {
return TAG_PARTIAL_SPAN.encode(s);
}
// The Span infrastructure should make sure that this invariant holds:
debug_assert!(span.lo <= span.hi);
if !s.source_file_cache.0.contains(span.lo) {
let source_map = s.tcx.sess.source_map();
let source_file_index = source_map.lookup_source_file_idx(span.lo);
s.source_file_cache =
(source_map.files()[source_file_index].clone(), source_file_index);
}
let (ref source_file, source_file_index) = s.source_file_cache;
debug_assert!(source_file.contains(span.lo));
if !source_file.contains(span.hi) {
// Unfortunately, macro expansion still sometimes generates Spans
// that malformed in this way.
return TAG_PARTIAL_SPAN.encode(s);
}
// There are two possible cases here:
// 1. This span comes from a 'foreign' crate - e.g. some crate upstream of the
// crate we are writing metadata for. When the metadata for *this* crate gets
// deserialized, the deserializer will need to know which crate it originally came
// from. We use `TAG_VALID_SPAN_FOREIGN` to indicate that a `CrateNum` should
// be deserialized after the rest of the span data, which tells the deserializer
// which crate contains the source map information.
// 2. This span comes from our own crate. No special handling is needed - we just
// write `TAG_VALID_SPAN_LOCAL` to let the deserializer know that it should use
// our own source map information.
//
// If we're a proc-macro crate, we always treat this as a local `Span`.
// In `encode_source_map`, we serialize foreign `SourceFile`s into our metadata
// if we're a proc-macro crate.
// This allows us to avoid loading the dependencies of proc-macro crates: all of
// the information we need to decode `Span`s is stored in the proc-macro crate.
let (tag, metadata_index) = if source_file.is_imported() && !s.is_proc_macro {
// To simplify deserialization, we 'rebase' this span onto the crate it originally came
// from (the crate that 'owns' the file it references. These rebased 'lo' and 'hi'
// values are relative to the source map information for the 'foreign' crate whose
// CrateNum we write into the metadata. This allows `imported_source_files` to binary
// search through the 'foreign' crate's source map information, using the
// deserialized 'lo' and 'hi' values directly.
//
// All of this logic ensures that the final result of deserialization is a 'normal'
// Span that can be used without any additional trouble.
let metadata_index = {
// Introduce a new scope so that we drop the 'lock()' temporary
match &*source_file.external_src.lock() {
ExternalSource::Foreign { metadata_index, .. } => *metadata_index,
src => panic!("Unexpected external source {:?}", src),
}
};
(TAG_VALID_SPAN_FOREIGN, metadata_index)
} else {
// Record the fact that we need to encode the data for this `SourceFile`
let source_files =
s.required_source_files.as_mut().expect("Already encoded SourceMap!");
let (metadata_index, _) = source_files.insert_full(source_file_index);
let metadata_index: u32 =
metadata_index.try_into().expect("cannot export more than U32_MAX files");
(TAG_VALID_SPAN_LOCAL, metadata_index)
};
// Encode the start position relative to the file start, so we profit more from the
// variable-length integer encoding.
let lo = span.lo - source_file.start_pos;
// Encode length which is usually less than span.hi and profits more
// from the variable-length integer encoding that we use.
let len = span.hi - span.lo;
tag.encode(s);
lo.encode(s);
len.encode(s);
// Encode the index of the `SourceFile` for the span, in order to make decoding faster.
metadata_index.encode(s);
if tag == TAG_VALID_SPAN_FOREIGN {
// This needs to be two lines to avoid holding the `s.source_file_cache`
// while calling `cnum.encode(s)`
let cnum = s.source_file_cache.0.cnum;
cnum.encode(s);
}
}
}
impl<'a, 'tcx> Encodable<EncodeContext<'a, 'tcx>> for Symbol {
fn encode(&self, s: &mut EncodeContext<'a, 'tcx>) {
// if symbol preinterned, emit tag and symbol index
if self.is_preinterned() {
s.opaque.emit_u8(SYMBOL_PREINTERNED);
s.opaque.emit_u32(self.as_u32());
} else {
// otherwise write it as string or as offset to it
match s.symbol_table.entry(*self) {
Entry::Vacant(o) => {
s.opaque.emit_u8(SYMBOL_STR);
let pos = s.opaque.position();
o.insert(pos);
s.emit_str(self.as_str());
}
Entry::Occupied(o) => {
let x = o.get().clone();
s.emit_u8(SYMBOL_OFFSET);
s.emit_usize(x);
}
}
}
}
}
impl<'a, 'tcx> TyEncoder for EncodeContext<'a, 'tcx> {
const CLEAR_CROSS_CRATE: bool = true;
type I = TyCtxt<'tcx>;
fn position(&self) -> usize {
self.opaque.position()
}
fn type_shorthands(&mut self) -> &mut FxHashMap<Ty<'tcx>, usize> {
&mut self.type_shorthands
}
fn predicate_shorthands(&mut self) -> &mut FxHashMap<ty::PredicateKind<'tcx>, usize> {
&mut self.predicate_shorthands
}
fn encode_alloc_id(&mut self, alloc_id: &rustc_middle::mir::interpret::AllocId) {
let (index, _) = self.interpret_allocs.insert_full(*alloc_id);
index.encode(self);
}
}
// Shorthand for `$self.$tables.$table.set($def_id.index, $self.lazy_value($value))`, which would
// normally need extra variables to avoid errors about multiple mutable borrows.
macro_rules! record {
($self:ident.$tables:ident.$table:ident[$def_id:expr] <- $value:expr) => {{
{
let value = $value;
let lazy = $self.lazy(value);
$self.$tables.$table.set($def_id.index, lazy);
}
}};
}
// Shorthand for `$self.$tables.$table.set($def_id.index, $self.lazy_value($value))`, which would
// normally need extra variables to avoid errors about multiple mutable borrows.
macro_rules! record_array {
($self:ident.$tables:ident.$table:ident[$def_id:expr] <- $value:expr) => {{
{
let value = $value;
let lazy = $self.lazy_array(value);
$self.$tables.$table.set($def_id.index, lazy);
}
}};
}
impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
fn emit_lazy_distance(&mut self, position: NonZeroUsize) {
let pos = position.get();
let distance = match self.lazy_state {
LazyState::NoNode => bug!("emit_lazy_distance: outside of a metadata node"),
LazyState::NodeStart(start) => {
let start = start.get();
assert!(pos <= start);
start - pos
}
LazyState::Previous(last_pos) => {
assert!(
last_pos <= position,
"make sure that the calls to `lazy*` \
are in the same order as the metadata fields",
);
position.get() - last_pos.get()
}
};
self.lazy_state = LazyState::Previous(NonZeroUsize::new(pos).unwrap());
self.emit_usize(distance);
}
fn lazy<T: ParameterizedOverTcx, B: Borrow<T::Value<'tcx>>>(&mut self, value: B) -> LazyValue<T>
where
T::Value<'tcx>: Encodable<EncodeContext<'a, 'tcx>>,
{
let pos = NonZeroUsize::new(self.position()).unwrap();
assert_eq!(self.lazy_state, LazyState::NoNode);
self.lazy_state = LazyState::NodeStart(pos);
value.borrow().encode(self);
self.lazy_state = LazyState::NoNode;
assert!(pos.get() <= self.position());
LazyValue::from_position(pos)
}
fn lazy_array<T: ParameterizedOverTcx, I: IntoIterator<Item = B>, B: Borrow<T::Value<'tcx>>>(
&mut self,
values: I,
) -> LazyArray<T>
where
T::Value<'tcx>: Encodable<EncodeContext<'a, 'tcx>>,
{
let pos = NonZeroUsize::new(self.position()).unwrap();
assert_eq!(self.lazy_state, LazyState::NoNode);
self.lazy_state = LazyState::NodeStart(pos);
let len = values.into_iter().map(|value| value.borrow().encode(self)).count();
self.lazy_state = LazyState::NoNode;
assert!(pos.get() <= self.position());
LazyArray::from_position_and_num_elems(pos, len)
}
fn encode_info_for_items(&mut self) {
self.encode_info_for_mod(CRATE_DEF_ID, self.tcx.hir().root_module());
// Proc-macro crates only export proc-macro items, which are looked
// up using `proc_macro_data`
if self.is_proc_macro {
return;
}
self.tcx.hir().visit_all_item_likes_in_crate(self);
}
fn encode_def_path_table(&mut self) {
let table = self.tcx.def_path_table();
if self.is_proc_macro {
for def_index in std::iter::once(CRATE_DEF_INDEX)
.chain(self.tcx.resolutions(()).proc_macros.iter().map(|p| p.local_def_index))
{
let def_key = self.lazy(table.def_key(def_index));
let def_path_hash = table.def_path_hash(def_index);
self.tables.def_keys.set(def_index, def_key);
self.tables.def_path_hashes.set(def_index, def_path_hash);
}
} else {
for (def_index, def_key, def_path_hash) in table.enumerated_keys_and_path_hashes() {
let def_key = self.lazy(def_key);
self.tables.def_keys.set(def_index, def_key);
self.tables.def_path_hashes.set(def_index, *def_path_hash);
}
}
}
fn encode_def_path_hash_map(&mut self) -> LazyValue<DefPathHashMapRef<'static>> {
self.lazy(DefPathHashMapRef::BorrowedFromTcx(self.tcx.def_path_hash_to_def_index_map()))
}
fn encode_source_map(&mut self) -> LazyTable<u32, LazyValue<rustc_span::SourceFile>> {
let source_map = self.tcx.sess.source_map();
let all_source_files = source_map.files();
// By replacing the `Option` with `None`, we ensure that we can't
// accidentally serialize any more `Span`s after the source map encoding
// is done.
let required_source_files = self.required_source_files.take().unwrap();
let working_directory = &self.tcx.sess.opts.working_dir;
let mut adapted = TableBuilder::default();
// Only serialize `SourceFile`s that were used during the encoding of a `Span`.
//
// The order in which we encode source files is important here: the on-disk format for
// `Span` contains the index of the corresponding `SourceFile`.
for (on_disk_index, &source_file_index) in required_source_files.iter().enumerate() {
let source_file = &all_source_files[source_file_index];
// Don't serialize imported `SourceFile`s, unless we're in a proc-macro crate.
assert!(!source_file.is_imported() || self.is_proc_macro);
// At export time we expand all source file paths to absolute paths because
// downstream compilation sessions can have a different compiler working
// directory, so relative paths from this or any other upstream crate
// won't be valid anymore.
//
// At this point we also erase the actual on-disk path and only keep
// the remapped version -- as is necessary for reproducible builds.
let mut source_file = match source_file.name {
FileName::Real(ref original_file_name) => {
let adapted_file_name = source_map
.path_mapping()
.to_embeddable_absolute_path(original_file_name.clone(), working_directory);
if adapted_file_name != *original_file_name {
let mut adapted: SourceFile = (**source_file).clone();
adapted.name = FileName::Real(adapted_file_name);
adapted.name_hash = {
let mut hasher: StableHasher = StableHasher::new();
adapted.name.hash(&mut hasher);
hasher.finish::<u128>()
};
Lrc::new(adapted)
} else {
// Nothing to adapt
source_file.clone()
}
}
// expanded code, not from a file
_ => source_file.clone(),
};
// We're serializing this `SourceFile` into our crate metadata,
// so mark it as coming from this crate.
// This also ensures that we don't try to deserialize the
// `CrateNum` for a proc-macro dependency - since proc macro
// dependencies aren't loaded when we deserialize a proc-macro,
// trying to remap the `CrateNum` would fail.
if self.is_proc_macro {
Lrc::make_mut(&mut source_file).cnum = LOCAL_CRATE;
}
let on_disk_index: u32 =
on_disk_index.try_into().expect("cannot export more than U32_MAX files");
adapted.set(on_disk_index, self.lazy(source_file));
}
adapted.encode(&mut self.opaque)
}
fn encode_crate_root(&mut self) -> LazyValue<CrateRoot> {
let tcx = self.tcx;
let mut stats: Vec<(&'static str, usize)> = Vec::with_capacity(32);
macro_rules! stat {
($label:literal, $f:expr) => {{
let orig_pos = self.position();
let res = $f();
stats.push(($label, self.position() - orig_pos));
res
}};
}
// We have already encoded some things. Get their combined size from the current position.
stats.push(("preamble", self.position()));
let (crate_deps, dylib_dependency_formats) =
stat!("dep", || (self.encode_crate_deps(), self.encode_dylib_dependency_formats()));
let lib_features = stat!("lib-features", || self.encode_lib_features());
let stability_implications =
stat!("stability-implications", || self.encode_stability_implications());
let (lang_items, lang_items_missing) = stat!("lang-items", || {
(self.encode_lang_items(), self.encode_lang_items_missing())
});
let diagnostic_items = stat!("diagnostic-items", || self.encode_diagnostic_items());
let native_libraries = stat!("native-libs", || self.encode_native_libraries());
let foreign_modules = stat!("foreign-modules", || self.encode_foreign_modules());
_ = stat!("def-path-table", || self.encode_def_path_table());
// Encode the def IDs of traits, for rustdoc and diagnostics.
let traits = stat!("traits", || self.encode_traits());
// Encode the def IDs of impls, for coherence checking.
let impls = stat!("impls", || self.encode_impls());
let incoherent_impls = stat!("incoherent-impls", || self.encode_incoherent_impls());
_ = stat!("mir", || self.encode_mir());
_ = stat!("items", || {
self.encode_def_ids();
self.encode_info_for_items();
});
let interpret_alloc_index = stat!("interpret-alloc-index", || {
let mut interpret_alloc_index = Vec::new();
let mut n = 0;
trace!("beginning to encode alloc ids");
loop {
let new_n = self.interpret_allocs.len();
// if we have found new ids, serialize those, too
if n == new_n {
// otherwise, abort
break;
}
trace!("encoding {} further alloc ids", new_n - n);
for idx in n..new_n {
let id = self.interpret_allocs[idx];
let pos = self.position() as u32;
interpret_alloc_index.push(pos);
interpret::specialized_encode_alloc_id(self, tcx, id);
}
n = new_n;
}
self.lazy_array(interpret_alloc_index)
});
// Encode the proc macro data. This affects `tables`, so we need to do this before we
// encode the tables. This overwrites def_keys, so it must happen after
// encode_def_path_table.
let proc_macro_data = stat!("proc-macro-data", || self.encode_proc_macros());
let tables = stat!("tables", || self.tables.encode(&mut self.opaque));
let debugger_visualizers =
stat!("debugger-visualizers", || self.encode_debugger_visualizers());
// Encode exported symbols info. This is prefetched in `encode_metadata` so we encode
// this as late as possible to give the prefetching as much time as possible to complete.
let exported_symbols = stat!("exported-symbols", || {
self.encode_exported_symbols(&tcx.exported_symbols(LOCAL_CRATE))
});
// Encode the hygiene data.
// IMPORTANT: this *must* be the last thing that we encode (other than `SourceMap`). The
// process of encoding other items (e.g. `optimized_mir`) may cause us to load data from
// the incremental cache. If this causes us to deserialize a `Span`, then we may load
// additional `SyntaxContext`s into the global `HygieneData`. Therefore, we need to encode
// the hygiene data last to ensure that we encode any `SyntaxContext`s that might be used.
let (syntax_contexts, expn_data, expn_hashes) = stat!("hygiene", || self.encode_hygiene());
let def_path_hash_map = stat!("def-path-hash-map", || self.encode_def_path_hash_map());
// Encode source_map. This needs to be done last, because encoding `Span`s tells us which
// `SourceFiles` we actually need to encode.
let source_map = stat!("source-map", || self.encode_source_map());
let root = stat!("final", || {
let attrs = tcx.hir().krate_attrs();
self.lazy(CrateRoot {
name: tcx.crate_name(LOCAL_CRATE),
extra_filename: tcx.sess.opts.cg.extra_filename.clone(),
triple: tcx.sess.opts.target_triple.clone(),
hash: tcx.crate_hash(LOCAL_CRATE),
stable_crate_id: tcx.def_path_hash(LOCAL_CRATE.as_def_id()).stable_crate_id(),
required_panic_strategy: tcx.required_panic_strategy(LOCAL_CRATE),
panic_in_drop_strategy: tcx.sess.opts.unstable_opts.panic_in_drop,
edition: tcx.sess.edition(),
has_global_allocator: tcx.has_global_allocator(LOCAL_CRATE),
has_alloc_error_handler: tcx.has_alloc_error_handler(LOCAL_CRATE),
has_panic_handler: tcx.has_panic_handler(LOCAL_CRATE),
has_default_lib_allocator: tcx
.sess
.contains_name(&attrs, sym::default_lib_allocator),
proc_macro_data,
debugger_visualizers,
compiler_builtins: tcx.sess.contains_name(&attrs, sym::compiler_builtins),
needs_allocator: tcx.sess.contains_name(&attrs, sym::needs_allocator),
needs_panic_runtime: tcx.sess.contains_name(&attrs, sym::needs_panic_runtime),
no_builtins: tcx.sess.contains_name(&attrs, sym::no_builtins),
panic_runtime: tcx.sess.contains_name(&attrs, sym::panic_runtime),
profiler_runtime: tcx.sess.contains_name(&attrs, sym::profiler_runtime),
symbol_mangling_version: tcx.sess.opts.get_symbol_mangling_version(),
crate_deps,
dylib_dependency_formats,
lib_features,
stability_implications,
lang_items,
diagnostic_items,
lang_items_missing,
native_libraries,
foreign_modules,
source_map,
traits,
impls,
incoherent_impls,
exported_symbols,
interpret_alloc_index,
tables,
syntax_contexts,
expn_data,
expn_hashes,
def_path_hash_map,
})
});
let total_bytes = self.position();
let computed_total_bytes: usize = stats.iter().map(|(_, size)| size).sum();
assert_eq!(total_bytes, computed_total_bytes);
if tcx.sess.meta_stats() {
self.opaque.flush();
// Rewind and re-read all the metadata to count the zero bytes we wrote.
let pos_before_rewind = self.opaque.file().stream_position().unwrap();
let mut zero_bytes = 0;
self.opaque.file().rewind().unwrap();
let file = std::io::BufReader::new(self.opaque.file());
for e in file.bytes() {
if e.unwrap() == 0 {
zero_bytes += 1;
}
}
assert_eq!(self.opaque.file().stream_position().unwrap(), pos_before_rewind);
stats.sort_by_key(|&(_, usize)| usize);
let prefix = "meta-stats";
let perc = |bytes| (bytes * 100) as f64 / total_bytes as f64;
eprintln!("{} METADATA STATS", prefix);
eprintln!("{} {:<23}{:>10}", prefix, "Section", "Size");
eprintln!(
"{} ----------------------------------------------------------------",
prefix
);
for (label, size) in stats {
eprintln!(
"{} {:<23}{:>10} ({:4.1}%)",
prefix,
label,
to_readable_str(size),
perc(size)
);
}
eprintln!(
"{} ----------------------------------------------------------------",
prefix
);
eprintln!(
"{} {:<23}{:>10} (of which {:.1}% are zero bytes)",
prefix,
"Total",
to_readable_str(total_bytes),
perc(zero_bytes)
);
eprintln!("{}", prefix);
}
root
}
}
/// Returns whether an attribute needs to be recorded in metadata, that is, if it's usable and
/// useful in downstream crates. Local-only attributes are an obvious example, but some
/// rustdoc-specific attributes can equally be of use while documenting the current crate only.
///
/// Removing these superfluous attributes speeds up compilation by making the metadata smaller.
///
/// Note: the `is_def_id_public` parameter is used to cache whether the given `DefId` has a public
/// visibility: this is a piece of data that can be computed once per defid, and not once per
/// attribute. Some attributes would only be usable downstream if they are public.
#[inline]
fn should_encode_attr(
tcx: TyCtxt<'_>,
attr: &Attribute,
def_id: LocalDefId,
is_def_id_public: &mut Option<bool>,
) -> bool {
if rustc_feature::is_builtin_only_local(attr.name_or_empty()) {
// Attributes marked local-only don't need to be encoded for downstream crates.
false
} else if attr.doc_str().is_some() {
// We keep all public doc comments because they might be "imported" into downstream crates
// if they use `#[doc(inline)]` to copy an item's documentation into their own.
*is_def_id_public.get_or_insert_with(|| tcx.effective_visibilities(()).is_exported(def_id))
} else if attr.has_name(sym::doc) {
// If this is a `doc` attribute, and it's marked `inline` (as in `#[doc(inline)]`), we can
// remove it. It won't be inlinable in downstream crates.
attr.meta_item_list().map(|l| l.iter().any(|l| !l.has_name(sym::inline))).unwrap_or(false)
} else {
true
}
}
fn should_encode_visibility(def_kind: DefKind) -> bool {
match def_kind {
DefKind::Mod
| DefKind::Struct
| DefKind::Union
| DefKind::Enum
| DefKind::Variant
| DefKind::Trait
| DefKind::TyAlias
| DefKind::ForeignTy
| DefKind::TraitAlias
| DefKind::AssocTy
| DefKind::Fn
| DefKind::Const
| DefKind::Static(..)
| DefKind::Ctor(..)
| DefKind::AssocFn
| DefKind::AssocConst
| DefKind::Macro(..)
| DefKind::Use
| DefKind::ForeignMod
| DefKind::OpaqueTy
| DefKind::ImplTraitPlaceholder
| DefKind::Impl
| DefKind::Field => true,
DefKind::TyParam
| DefKind::ConstParam
| DefKind::LifetimeParam
| DefKind::AnonConst
| DefKind::InlineConst
| DefKind::GlobalAsm
| DefKind::Closure
| DefKind::Generator
| DefKind::ExternCrate => false,
}
}
fn should_encode_stability(def_kind: DefKind) -> bool {
match def_kind {
DefKind::Mod
| DefKind::Ctor(..)
| DefKind::Variant
| DefKind::Field
| DefKind::Struct
| DefKind::AssocTy
| DefKind::AssocFn
| DefKind::AssocConst
| DefKind::TyParam
| DefKind::ConstParam
| DefKind::Static(..)
| DefKind::Const
| DefKind::Fn
| DefKind::ForeignMod
| DefKind::TyAlias
| DefKind::OpaqueTy
| DefKind::ImplTraitPlaceholder
| DefKind::Enum
| DefKind::Union
| DefKind::Impl
| DefKind::Trait
| DefKind::TraitAlias
| DefKind::Macro(..)
| DefKind::ForeignTy => true,
DefKind::Use
| DefKind::LifetimeParam
| DefKind::AnonConst
| DefKind::InlineConst
| DefKind::GlobalAsm
| DefKind::Closure
| DefKind::Generator
| DefKind::ExternCrate => false,
}
}
/// Whether we should encode MIR.
///
/// Computing, optimizing and encoding the MIR is a relatively expensive operation.
/// We want to avoid this work when not required. Therefore:
/// - we only compute `mir_for_ctfe` on items with const-eval semantics;
/// - we skip `optimized_mir` for check runs.
///
/// Return a pair, resp. for CTFE and for LLVM.
fn should_encode_mir(tcx: TyCtxt<'_>, def_id: LocalDefId) -> (bool, bool) {
match tcx.def_kind(def_id) {
// Constructors
DefKind::Ctor(_, _) => {
let mir_opt_base = tcx.sess.opts.output_types.should_codegen()
|| tcx.sess.opts.unstable_opts.always_encode_mir;
(true, mir_opt_base)
}
// Constants
DefKind::AnonConst
| DefKind::InlineConst
| DefKind::AssocConst
| DefKind::Static(..)
| DefKind::Const => (true, false),
// Full-fledged functions
DefKind::AssocFn | DefKind::Fn => {
let generics = tcx.generics_of(def_id);
let needs_inline = (generics.requires_monomorphization(tcx)
|| tcx.codegen_fn_attrs(def_id).requests_inline())
&& tcx.sess.opts.output_types.should_codegen();
// The function has a `const` modifier or is in a `#[const_trait]`.
let is_const_fn = tcx.is_const_fn_raw(def_id.to_def_id())
|| tcx.is_const_default_method(def_id.to_def_id());
let always_encode_mir = tcx.sess.opts.unstable_opts.always_encode_mir;
(is_const_fn, needs_inline || always_encode_mir)
}
// Closures can't be const fn.
DefKind::Closure => {
let generics = tcx.generics_of(def_id);
let needs_inline = (generics.requires_monomorphization(tcx)
|| tcx.codegen_fn_attrs(def_id).requests_inline())
&& tcx.sess.opts.output_types.should_codegen();
let always_encode_mir = tcx.sess.opts.unstable_opts.always_encode_mir;
(false, needs_inline || always_encode_mir)
}
// Generators require optimized MIR to compute layout.
DefKind::Generator => (false, true),
// The others don't have MIR.
_ => (false, false),
}
}
fn should_encode_variances(def_kind: DefKind) -> bool {
match def_kind {
DefKind::Struct
| DefKind::Union
| DefKind::Enum
| DefKind::Variant
| DefKind::OpaqueTy
| DefKind::ImplTraitPlaceholder
| DefKind::Fn
| DefKind::Ctor(..)
| DefKind::AssocFn => true,
DefKind::Mod
| DefKind::Field
| DefKind::AssocTy
| DefKind::AssocConst
| DefKind::TyParam
| DefKind::ConstParam
| DefKind::Static(..)
| DefKind::Const
| DefKind::ForeignMod
| DefKind::TyAlias
| DefKind::Impl
| DefKind::Trait
| DefKind::TraitAlias
| DefKind::Macro(..)
| DefKind::ForeignTy
| DefKind::Use
| DefKind::LifetimeParam
| DefKind::AnonConst
| DefKind::InlineConst
| DefKind::GlobalAsm
| DefKind::Closure
| DefKind::Generator
| DefKind::ExternCrate => false,
}
}
fn should_encode_generics(def_kind: DefKind) -> bool {
match def_kind {
DefKind::Struct
| DefKind::Union
| DefKind::Enum
| DefKind::Variant
| DefKind::Trait
| DefKind::TyAlias
| DefKind::ForeignTy
| DefKind::TraitAlias
| DefKind::AssocTy
| DefKind::Fn
| DefKind::Const
| DefKind::Static(..)
| DefKind::Ctor(..)
| DefKind::AssocFn
| DefKind::AssocConst
| DefKind::AnonConst
| DefKind::InlineConst
| DefKind::OpaqueTy
| DefKind::ImplTraitPlaceholder
| DefKind::Impl
| DefKind::Field
| DefKind::TyParam
| DefKind::Closure
| DefKind::Generator => true,
DefKind::Mod
| DefKind::ForeignMod
| DefKind::ConstParam
| DefKind::Macro(..)
| DefKind::Use
| DefKind::LifetimeParam
| DefKind::GlobalAsm
| DefKind::ExternCrate => false,
}
}
fn should_encode_type(tcx: TyCtxt<'_>, def_id: LocalDefId, def_kind: DefKind) -> bool {
match def_kind {
DefKind::Struct
| DefKind::Union
| DefKind::Enum
| DefKind::Variant
| DefKind::Ctor(..)
| DefKind::Field
| DefKind::Fn
| DefKind::Const
| DefKind::Static(..)
| DefKind::TyAlias
| DefKind::OpaqueTy
| DefKind::ForeignTy
| DefKind::Impl
| DefKind::AssocFn
| DefKind::AssocConst
| DefKind::Closure
| DefKind::Generator
| DefKind::ConstParam
| DefKind::AnonConst
| DefKind::InlineConst => true,
DefKind::ImplTraitPlaceholder => {
let parent_def_id = tcx.impl_trait_in_trait_parent(def_id.to_def_id());
let assoc_item = tcx.associated_item(parent_def_id);
match assoc_item.container {
// Always encode an RPIT in an impl fn, since it always has a body
ty::AssocItemContainer::ImplContainer => true,
ty::AssocItemContainer::TraitContainer => {
// Encode an RPIT for a trait only if the trait has a default body
assoc_item.defaultness(tcx).has_value()
}
}
}
DefKind::AssocTy => {
let assoc_item = tcx.associated_item(def_id);
match assoc_item.container {
ty::AssocItemContainer::ImplContainer => true,
ty::AssocItemContainer::TraitContainer => assoc_item.defaultness(tcx).has_value(),
}
}
DefKind::TyParam => {
let hir::Node::GenericParam(param) = tcx.hir().get_by_def_id(def_id) else { bug!() };
let hir::GenericParamKind::Type { default, .. } = param.kind else { bug!() };
default.is_some()
}
DefKind::Trait
| DefKind::TraitAlias
| DefKind::Mod
| DefKind::ForeignMod
| DefKind::Macro(..)
| DefKind::Use
| DefKind::LifetimeParam
| DefKind::GlobalAsm
| DefKind::ExternCrate => false,
}
}
fn should_encode_const(def_kind: DefKind) -> bool {
match def_kind {
DefKind::Const | DefKind::AssocConst | DefKind::AnonConst => true,
DefKind::Struct
| DefKind::Union
| DefKind::Enum
| DefKind::Variant
| DefKind::Ctor(..)
| DefKind::Field
| DefKind::Fn
| DefKind::Static(..)
| DefKind::TyAlias
| DefKind::OpaqueTy
| DefKind::ImplTraitPlaceholder
| DefKind::ForeignTy
| DefKind::Impl
| DefKind::AssocFn
| DefKind::Closure
| DefKind::Generator
| DefKind::ConstParam
| DefKind::InlineConst
| DefKind::AssocTy
| DefKind::TyParam
| DefKind::Trait
| DefKind::TraitAlias
| DefKind::Mod
| DefKind::ForeignMod
| DefKind::Macro(..)
| DefKind::Use
| DefKind::LifetimeParam
| DefKind::GlobalAsm
| DefKind::ExternCrate => false,
}
}
fn should_encode_trait_impl_trait_tys<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
if tcx.def_kind(def_id) != DefKind::AssocFn {
return false;
}
let Some(item) = tcx.opt_associated_item(def_id) else { return false; };
if item.container != ty::AssocItemContainer::ImplContainer {
return false;
}
let Some(trait_item_def_id) = item.trait_item_def_id else { return false; };
// FIXME(RPITIT): This does a somewhat manual walk through the signature
// of the trait fn to look for any RPITITs, but that's kinda doing a lot
// of work. We can probably remove this when we refactor RPITITs to be
// associated types.
tcx.fn_sig(trait_item_def_id).skip_binder().output().walk().any(|arg| {
if let ty::GenericArgKind::Type(ty) = arg.unpack()
&& let ty::Projection(data) = ty.kind()
&& tcx.def_kind(data.item_def_id) == DefKind::ImplTraitPlaceholder
{
true
} else {
false
}
})
}
impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
fn encode_attrs(&mut self, def_id: LocalDefId) {
let tcx = self.tcx;
let mut is_public: Option<bool> = None;
let mut attrs = tcx
.hir()
.attrs(tcx.hir().local_def_id_to_hir_id(def_id))
.iter()
.filter(move |attr| should_encode_attr(tcx, attr, def_id, &mut is_public));
record_array!(self.tables.attributes[def_id.to_def_id()] <- attrs.clone());
if attrs.any(|attr| attr.may_have_doc_links()) {
self.tables.may_have_doc_links.set(def_id.local_def_index, ());
}
}
fn encode_def_ids(&mut self) {
if self.is_proc_macro {
return;
}
let tcx = self.tcx;
for local_id in tcx.iter_local_def_id() {
let def_id = local_id.to_def_id();
let def_kind = tcx.opt_def_kind(local_id);
let Some(def_kind) = def_kind else { continue };
self.tables.opt_def_kind.set(def_id.index, def_kind);
let def_span = tcx.def_span(local_id);
record!(self.tables.def_span[def_id] <- def_span);
self.encode_attrs(local_id);
record!(self.tables.expn_that_defined[def_id] <- self.tcx.expn_that_defined(def_id));
if let Some(ident_span) = tcx.def_ident_span(def_id) {
record!(self.tables.def_ident_span[def_id] <- ident_span);
}
if def_kind.has_codegen_attrs() {
record!(self.tables.codegen_fn_attrs[def_id] <- self.tcx.codegen_fn_attrs(def_id));
}
if should_encode_visibility(def_kind) {
let vis =
self.tcx.local_visibility(local_id).map_id(|def_id| def_id.local_def_index);
record!(self.tables.visibility[def_id] <- vis);
}
if should_encode_stability(def_kind) {
self.encode_stability(def_id);
self.encode_const_stability(def_id);
self.encode_default_body_stability(def_id);
self.encode_deprecation(def_id);
}
if should_encode_variances(def_kind) {
let v = self.tcx.variances_of(def_id);
record_array!(self.tables.variances_of[def_id] <- v);
}
if should_encode_generics(def_kind) {
let g = tcx.generics_of(def_id);
record!(self.tables.generics_of[def_id] <- g);
record!(self.tables.explicit_predicates_of[def_id] <- self.tcx.explicit_predicates_of(def_id));
let inferred_outlives = self.tcx.inferred_outlives_of(def_id);
if !inferred_outlives.is_empty() {
record_array!(self.tables.inferred_outlives_of[def_id] <- inferred_outlives);
}
}
if should_encode_type(tcx, local_id, def_kind) {
record!(self.tables.type_of[def_id] <- self.tcx.type_of(def_id));
}
if let DefKind::TyParam = def_kind {
let default = self.tcx.object_lifetime_default(def_id);
record!(self.tables.object_lifetime_default[def_id] <- default);
}
if let DefKind::Trait | DefKind::TraitAlias = def_kind {
record!(self.tables.super_predicates_of[def_id] <- self.tcx.super_predicates_of(def_id));
}
if let DefKind::Enum | DefKind::Struct | DefKind::Union = def_kind {
let params_in_repr = self.tcx.params_in_repr(def_id);
record!(self.tables.params_in_repr[def_id] <- params_in_repr);
}
if should_encode_trait_impl_trait_tys(tcx, def_id)
&& let Ok(table) = self.tcx.collect_trait_impl_trait_tys(def_id)
{
record!(self.tables.trait_impl_trait_tys[def_id] <- table);
}
}
let inherent_impls = tcx.crate_inherent_impls(());
for (def_id, implementations) in inherent_impls.inherent_impls.iter() {
if implementations.is_empty() {
continue;
}
record_array!(self.tables.inherent_impls[def_id.to_def_id()] <- implementations.iter().map(|&def_id| {
assert!(def_id.is_local());
def_id.index
}));
}
}
fn encode_enum_variant_info(&mut self, def: ty::AdtDef<'tcx>, index: VariantIdx) {
let tcx = self.tcx;
let variant = &def.variant(index);
let def_id = variant.def_id;
debug!("EncodeContext::encode_enum_variant_info({:?})", def_id);
let data = VariantData {
discr: variant.discr,
ctor: variant.ctor.map(|(kind, def_id)| (kind, def_id.index)),
is_non_exhaustive: variant.is_field_list_non_exhaustive(),
};
record!(self.tables.variant_data[def_id] <- data);
self.tables.constness.set(def_id.index, hir::Constness::Const);
record_array!(self.tables.children[def_id] <- variant.fields.iter().map(|f| {
assert!(f.did.is_local());
f.did.index
}));
if let Some((CtorKind::Fn, ctor_def_id)) = variant.ctor {
// FIXME(eddyb) encode signature only in `encode_enum_variant_ctor`.
record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(ctor_def_id));
}
}
fn encode_enum_variant_ctor(&mut self, def: ty::AdtDef<'tcx>, index: VariantIdx) {
let variant = &def.variant(index);
let Some((ctor_kind, def_id)) = variant.ctor else { return };
debug!("EncodeContext::encode_enum_variant_ctor({:?})", def_id);
// FIXME(eddyb) encode only the `CtorKind` for constructors.
let data = VariantData {
discr: variant.discr,
ctor: Some((ctor_kind, def_id.index)),
is_non_exhaustive: variant.is_field_list_non_exhaustive(),
};
record!(self.tables.variant_data[def_id] <- data);
self.tables.constness.set(def_id.index, hir::Constness::Const);
if ctor_kind == CtorKind::Fn {
record!(self.tables.fn_sig[def_id] <- self.tcx.fn_sig(def_id));
}
}
fn encode_info_for_mod(&mut self, local_def_id: LocalDefId, md: &hir::Mod<'_>) {
let tcx = self.tcx;
let def_id = local_def_id.to_def_id();
debug!("EncodeContext::encode_info_for_mod({:?})", def_id);
// If we are encoding a proc-macro crates, `encode_info_for_mod` will
// only ever get called for the crate root. We still want to encode
// the crate root for consistency with other crates (some of the resolver
// code uses it). However, we skip encoding anything relating to child
// items - we encode information about proc-macros later on.
if self.is_proc_macro {
// Encode this here because we don't do it in encode_def_ids.
record!(self.tables.expn_that_defined[def_id] <- tcx.expn_that_defined(local_def_id));
} else {
record_array!(self.tables.children[def_id] <- iter::from_generator(|| {
for item_id in md.item_ids {
match tcx.hir().item(*item_id).kind {
// Foreign items are planted into their parent modules
// from name resolution point of view.
hir::ItemKind::ForeignMod { items, .. } => {
for foreign_item in items {
yield foreign_item.id.owner_id.def_id.local_def_index;
}
}
// Only encode named non-reexport children, reexports are encoded
// separately and unnamed items are not used by name resolution.
hir::ItemKind::ExternCrate(..) => continue,
hir::ItemKind::Struct(ref vdata, _) => {
yield item_id.owner_id.def_id.local_def_index;
// Encode constructors which take a separate slot in value namespace.
if let Some(ctor_hir_id) = vdata.ctor_hir_id() {
yield tcx.hir().local_def_id(ctor_hir_id).local_def_index;
}
}
_ if tcx.def_key(item_id.owner_id.to_def_id()).get_opt_name().is_some() => {
yield item_id.owner_id.def_id.local_def_index;
}
_ => continue,
}
}
}));
if let Some(reexports) = tcx.module_reexports(local_def_id) {
assert!(!reexports.is_empty());
record_array!(self.tables.module_reexports[def_id] <- reexports);
}
}
}
fn encode_struct_ctor(&mut self, adt_def: ty::AdtDef<'tcx>) {
let variant = adt_def.non_enum_variant();
let Some((ctor_kind, def_id)) = variant.ctor else { return };
debug!("EncodeContext::encode_struct_ctor({:?})", def_id);
let data = VariantData {
discr: variant.discr,
ctor: Some((ctor_kind, def_id.index)),
is_non_exhaustive: variant.is_field_list_non_exhaustive(),
};
record!(self.tables.repr_options[def_id] <- adt_def.repr());
record!(self.tables.variant_data[def_id] <- data);
self.tables.constness.set(def_id.index, hir::Constness::Const);
if ctor_kind == CtorKind::Fn {
record!(self.tables.fn_sig[def_id] <- self.tcx.fn_sig(def_id));
}
}
fn encode_explicit_item_bounds(&mut self, def_id: DefId) {
debug!("EncodeContext::encode_explicit_item_bounds({:?})", def_id);
let bounds = self.tcx.explicit_item_bounds(def_id);
if !bounds.is_empty() {
record_array!(self.tables.explicit_item_bounds[def_id] <- bounds);
}
}
fn encode_info_for_trait_item(&mut self, def_id: DefId) {
debug!("EncodeContext::encode_info_for_trait_item({:?})", def_id);
let tcx = self.tcx;
let impl_defaultness = tcx.impl_defaultness(def_id.expect_local());
self.tables.impl_defaultness.set(def_id.index, impl_defaultness);
let trait_item = tcx.associated_item(def_id);
self.tables.assoc_container.set(def_id.index, trait_item.container);
match trait_item.kind {
ty::AssocKind::Const => {}
ty::AssocKind::Fn => {
record_array!(self.tables.fn_arg_names[def_id] <- tcx.fn_arg_names(def_id));
self.tables.asyncness.set(def_id.index, tcx.asyncness(def_id));
self.tables.constness.set(def_id.index, hir::Constness::NotConst);
}
ty::AssocKind::Type => {
self.encode_explicit_item_bounds(def_id);
}
}
if trait_item.kind == ty::AssocKind::Fn {
record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
}
}
fn encode_info_for_impl_item(&mut self, def_id: DefId) {
debug!("EncodeContext::encode_info_for_impl_item({:?})", def_id);
let tcx = self.tcx;
let ast_item = self.tcx.hir().expect_impl_item(def_id.expect_local());
self.tables.impl_defaultness.set(def_id.index, ast_item.defaultness);
let impl_item = self.tcx.associated_item(def_id);
self.tables.assoc_container.set(def_id.index, impl_item.container);
match impl_item.kind {
ty::AssocKind::Fn => {
let hir::ImplItemKind::Fn(ref sig, body) = ast_item.kind else { bug!() };
self.tables.asyncness.set(def_id.index, sig.header.asyncness);
record_array!(self.tables.fn_arg_names[def_id] <- self.tcx.hir().body_param_names(body));
// Can be inside `impl const Trait`, so using sig.header.constness is not reliable
let constness = if self.tcx.is_const_fn_raw(def_id) {
hir::Constness::Const
} else {
hir::Constness::NotConst
};
self.tables.constness.set(def_id.index, constness);
}
ty::AssocKind::Const | ty::AssocKind::Type => {}
}
if let Some(trait_item_def_id) = impl_item.trait_item_def_id {
self.tables.trait_item_def_id.set(def_id.index, trait_item_def_id.into());
}
if impl_item.kind == ty::AssocKind::Fn {
record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
if tcx.is_intrinsic(def_id) {
self.tables.is_intrinsic.set(def_id.index, ());
}
}
}
fn encode_mir(&mut self) {
if self.is_proc_macro {
return;
}
let tcx = self.tcx;
let keys_and_jobs = tcx.mir_keys(()).iter().filter_map(|&def_id| {
let (encode_const, encode_opt) = should_encode_mir(tcx, def_id);
if encode_const || encode_opt { Some((def_id, encode_const, encode_opt)) } else { None }
});
for (def_id, encode_const, encode_opt) in keys_and_jobs {
debug_assert!(encode_const || encode_opt);
debug!("EntryBuilder::encode_mir({:?})", def_id);
if encode_opt {
record!(self.tables.optimized_mir[def_id.to_def_id()] <- tcx.optimized_mir(def_id));
}
if encode_const {
record!(self.tables.mir_for_ctfe[def_id.to_def_id()] <- tcx.mir_for_ctfe(def_id));
// FIXME(generic_const_exprs): this feels wrong to have in `encode_mir`
let abstract_const = tcx.thir_abstract_const(def_id);
if let Ok(Some(abstract_const)) = abstract_const {
record!(self.tables.thir_abstract_const[def_id.to_def_id()] <- abstract_const);
}
if should_encode_const(tcx.def_kind(def_id)) {
let qualifs = tcx.mir_const_qualif(def_id);
record!(self.tables.mir_const_qualif[def_id.to_def_id()] <- qualifs);
let body_id = tcx.hir().maybe_body_owned_by(def_id);
if let Some(body_id) = body_id {
let const_data = self.encode_rendered_const_for_body(body_id);
record!(self.tables.rendered_const[def_id.to_def_id()] <- const_data);
}
}
}
record!(self.tables.promoted_mir[def_id.to_def_id()] <- tcx.promoted_mir(def_id));
let instance =
ty::InstanceDef::Item(ty::WithOptConstParam::unknown(def_id.to_def_id()));
let unused = tcx.unused_generic_params(instance);
if !unused.is_empty() {
record!(self.tables.unused_generic_params[def_id.to_def_id()] <- unused);
}
}
// Encode all the deduced parameter attributes for everything that has MIR, even for items
// that can't be inlined. But don't if we aren't optimizing in non-incremental mode, to
// save the query traffic.
if tcx.sess.opts.output_types.should_codegen()
&& tcx.sess.opts.optimize != OptLevel::No
&& tcx.sess.opts.incremental.is_none()
{
for &local_def_id in tcx.mir_keys(()) {
if let DefKind::AssocFn | DefKind::Fn = tcx.def_kind(local_def_id) {
record_array!(self.tables.deduced_param_attrs[local_def_id.to_def_id()] <-
self.tcx.deduced_param_attrs(local_def_id.to_def_id()));
}
}
}
}
fn encode_stability(&mut self, def_id: DefId) {
debug!("EncodeContext::encode_stability({:?})", def_id);
// The query lookup can take a measurable amount of time in crates with many items. Check if
// the stability attributes are even enabled before using their queries.
if self.feat.staged_api || self.tcx.sess.opts.unstable_opts.force_unstable_if_unmarked {
if let Some(stab) = self.tcx.lookup_stability(def_id) {
record!(self.tables.lookup_stability[def_id] <- stab)
}
}
}
fn encode_const_stability(&mut self, def_id: DefId) {
debug!("EncodeContext::encode_const_stability({:?})", def_id);
// The query lookup can take a measurable amount of time in crates with many items. Check if
// the stability attributes are even enabled before using their queries.
if self.feat.staged_api || self.tcx.sess.opts.unstable_opts.force_unstable_if_unmarked {
if let Some(stab) = self.tcx.lookup_const_stability(def_id) {
record!(self.tables.lookup_const_stability[def_id] <- stab)
}
}
}
fn encode_default_body_stability(&mut self, def_id: DefId) {
debug!("EncodeContext::encode_default_body_stability({:?})", def_id);
// The query lookup can take a measurable amount of time in crates with many items. Check if
// the stability attributes are even enabled before using their queries.
if self.feat.staged_api || self.tcx.sess.opts.unstable_opts.force_unstable_if_unmarked {
if let Some(stab) = self.tcx.lookup_default_body_stability(def_id) {
record!(self.tables.lookup_default_body_stability[def_id] <- stab)
}
}
}
fn encode_deprecation(&mut self, def_id: DefId) {
debug!("EncodeContext::encode_deprecation({:?})", def_id);
if let Some(depr) = self.tcx.lookup_deprecation(def_id) {
record!(self.tables.lookup_deprecation_entry[def_id] <- depr);
}
}
fn encode_rendered_const_for_body(&mut self, body_id: hir::BodyId) -> String {
let hir = self.tcx.hir();
let body = hir.body(body_id);
rustc_hir_pretty::to_string(&(&hir as &dyn intravisit::Map<'_>), |s| {
s.print_expr(&body.value)
})
}
fn encode_info_for_item(&mut self, def_id: DefId, item: &'tcx hir::Item<'tcx>) {
let tcx = self.tcx;
debug!("EncodeContext::encode_info_for_item({:?})", def_id);
match item.kind {
hir::ItemKind::Fn(ref sig, .., body) => {
self.tables.asyncness.set(def_id.index, sig.header.asyncness);
record_array!(self.tables.fn_arg_names[def_id] <- self.tcx.hir().body_param_names(body));
self.tables.constness.set(def_id.index, sig.header.constness);
}
hir::ItemKind::Macro(ref macro_def, _) => {
if macro_def.macro_rules {
self.tables.macro_rules.set(def_id.index, ());
}
record!(self.tables.macro_definition[def_id] <- &*macro_def.body);
}
hir::ItemKind::Mod(ref m) => {
return self.encode_info_for_mod(item.owner_id.def_id, m);
}
hir::ItemKind::OpaqueTy(..) => {
self.encode_explicit_item_bounds(def_id);
}
hir::ItemKind::Enum(..) => {
let adt_def = self.tcx.adt_def(def_id);
record!(self.tables.repr_options[def_id] <- adt_def.repr());
}
hir::ItemKind::Struct(..) => {
let adt_def = self.tcx.adt_def(def_id);
record!(self.tables.repr_options[def_id] <- adt_def.repr());
self.tables.constness.set(def_id.index, hir::Constness::Const);
let variant = adt_def.non_enum_variant();
record!(self.tables.variant_data[def_id] <- VariantData {
discr: variant.discr,
ctor: variant.ctor.map(|(kind, def_id)| (kind, def_id.index)),
is_non_exhaustive: variant.is_field_list_non_exhaustive(),
});
}
hir::ItemKind::Union(..) => {
let adt_def = self.tcx.adt_def(def_id);
record!(self.tables.repr_options[def_id] <- adt_def.repr());
let variant = adt_def.non_enum_variant();
record!(self.tables.variant_data[def_id] <- VariantData {
discr: variant.discr,
ctor: variant.ctor.map(|(kind, def_id)| (kind, def_id.index)),
is_non_exhaustive: variant.is_field_list_non_exhaustive(),
});
}
hir::ItemKind::Impl(hir::Impl { defaultness, constness, .. }) => {
self.tables.impl_defaultness.set(def_id.index, *defaultness);
self.tables.constness.set(def_id.index, *constness);
let trait_ref = self.tcx.impl_trait_ref(def_id);
if let Some(trait_ref) = trait_ref {
let trait_def = self.tcx.trait_def(trait_ref.def_id);
if let Some(mut an) = trait_def.ancestors(self.tcx, def_id).ok() {
if let Some(specialization_graph::Node::Impl(parent)) = an.nth(1) {
self.tables.impl_parent.set(def_id.index, parent.into());
}
}
// if this is an impl of `CoerceUnsized`, create its
// "unsized info", else just store None
if Some(trait_ref.def_id) == self.tcx.lang_items().coerce_unsized_trait() {
let coerce_unsized_info =
self.tcx.at(item.span).coerce_unsized_info(def_id);
record!(self.tables.coerce_unsized_info[def_id] <- coerce_unsized_info);
}
}
let polarity = self.tcx.impl_polarity(def_id);
self.tables.impl_polarity.set(def_id.index, polarity);
}
hir::ItemKind::Trait(..) => {
let trait_def = self.tcx.trait_def(def_id);
record!(self.tables.trait_def[def_id] <- trait_def);
}
hir::ItemKind::TraitAlias(..) => {
let trait_def = self.tcx.trait_def(def_id);
record!(self.tables.trait_def[def_id] <- trait_def);
}
hir::ItemKind::ExternCrate(_) | hir::ItemKind::Use(..) => {
bug!("cannot encode info for item {:?}", item)
}
hir::ItemKind::Static(..)
| hir::ItemKind::Const(..)
| hir::ItemKind::ForeignMod { .. }
| hir::ItemKind::GlobalAsm(..)
| hir::ItemKind::TyAlias(..) => {}
};
// FIXME(eddyb) there should be a nicer way to do this.
match item.kind {
hir::ItemKind::Enum(..) => {
record_array!(self.tables.children[def_id] <- iter::from_generator(||
for variant in tcx.adt_def(def_id).variants() {
yield variant.def_id.index;
// Encode constructors which take a separate slot in value namespace.
if let Some(ctor_def_id) = variant.ctor_def_id() {
yield ctor_def_id.index;
}
}
))
}
hir::ItemKind::Struct(..) | hir::ItemKind::Union(..) => {
record_array!(self.tables.children[def_id] <-
self.tcx.adt_def(def_id).non_enum_variant().fields.iter().map(|f| {
assert!(f.did.is_local());
f.did.index
})
)
}
hir::ItemKind::Impl { .. } | hir::ItemKind::Trait(..) => {
let associated_item_def_ids = self.tcx.associated_item_def_ids(def_id);
record_array!(self.tables.children[def_id] <-
associated_item_def_ids.iter().map(|&def_id| {
assert!(def_id.is_local());
def_id.index
})
);
}
_ => {}
}
if let hir::ItemKind::Fn(..) = item.kind {
record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
if tcx.is_intrinsic(def_id) {
self.tables.is_intrinsic.set(def_id.index, ());
}
}
if let hir::ItemKind::Impl { .. } = item.kind {
if let Some(trait_ref) = self.tcx.impl_trait_ref(def_id) {
record!(self.tables.impl_trait_ref[def_id] <- trait_ref);
}
}
// In some cases, along with the item itself, we also
// encode some sub-items. Usually we want some info from the item
// so it's easier to do that here then to wait until we would encounter
// normally in the visitor walk.
match item.kind {
hir::ItemKind::Enum(..) => {
let def = self.tcx.adt_def(item.owner_id.to_def_id());
for (i, _) in def.variants().iter_enumerated() {
self.encode_enum_variant_info(def, i);
self.encode_enum_variant_ctor(def, i);
}
}
hir::ItemKind::Struct(..) => {
let def = self.tcx.adt_def(item.owner_id.to_def_id());
self.encode_struct_ctor(def);
}
hir::ItemKind::Impl { .. } => {
for &trait_item_def_id in
self.tcx.associated_item_def_ids(item.owner_id.to_def_id()).iter()
{
self.encode_info_for_impl_item(trait_item_def_id);
}
}
hir::ItemKind::Trait(..) => {
for &item_def_id in
self.tcx.associated_item_def_ids(item.owner_id.to_def_id()).iter()
{
self.encode_info_for_trait_item(item_def_id);
}
}
_ => {}
}
}
#[instrument(level = "debug", skip(self))]
fn encode_info_for_closure(&mut self, def_id: LocalDefId) {
// NOTE(eddyb) `tcx.type_of(def_id)` isn't used because it's fully generic,
// including on the signature, which is inferred in `typeck.
let typeck_result: &'tcx ty::TypeckResults<'tcx> = self.tcx.typeck(def_id);
let hir_id = self.tcx.hir().local_def_id_to_hir_id(def_id);
let ty = typeck_result.node_type(hir_id);
match ty.kind() {
ty::Generator(..) => {
let data = self.tcx.generator_kind(def_id).unwrap();
let generator_diagnostic_data = typeck_result.get_generator_diagnostic_data();
record!(self.tables.generator_kind[def_id.to_def_id()] <- data);
record!(self.tables.generator_diagnostic_data[def_id.to_def_id()] <- generator_diagnostic_data);
}
ty::Closure(_, substs) => {
record!(self.tables.fn_sig[def_id.to_def_id()] <- substs.as_closure().sig());
}
_ => bug!("closure that is neither generator nor closure"),
}
}
fn encode_native_libraries(&mut self) -> LazyArray<NativeLib> {
empty_proc_macro!(self);
let used_libraries = self.tcx.native_libraries(LOCAL_CRATE);
self.lazy_array(used_libraries.iter())
}
fn encode_foreign_modules(&mut self) -> LazyArray<ForeignModule> {
empty_proc_macro!(self);
let foreign_modules = self.tcx.foreign_modules(LOCAL_CRATE);
self.lazy_array(foreign_modules.iter().map(|(_, m)| m).cloned())
}
fn encode_hygiene(&mut self) -> (SyntaxContextTable, ExpnDataTable, ExpnHashTable) {
let mut syntax_contexts: TableBuilder<_, _> = Default::default();
let mut expn_data_table: TableBuilder<_, _> = Default::default();
let mut expn_hash_table: TableBuilder<_, _> = Default::default();
self.hygiene_ctxt.encode(
&mut (&mut *self, &mut syntax_contexts, &mut expn_data_table, &mut expn_hash_table),
|(this, syntax_contexts, _, _), index, ctxt_data| {
syntax_contexts.set(index, this.lazy(ctxt_data));
},
|(this, _, expn_data_table, expn_hash_table), index, expn_data, hash| {
if let Some(index) = index.as_local() {
expn_data_table.set(index.as_raw(), this.lazy(expn_data));
expn_hash_table.set(index.as_raw(), this.lazy(hash));
}
},
);
(
syntax_contexts.encode(&mut self.opaque),
expn_data_table.encode(&mut self.opaque),
expn_hash_table.encode(&mut self.opaque),
)
}
fn encode_proc_macros(&mut self) -> Option<ProcMacroData> {
let is_proc_macro = self.tcx.sess.crate_types().contains(&CrateType::ProcMacro);
if is_proc_macro {
let tcx = self.tcx;
let hir = tcx.hir();
let proc_macro_decls_static = tcx.proc_macro_decls_static(()).unwrap().local_def_index;
let stability = tcx.lookup_stability(CRATE_DEF_ID);
let macros =
self.lazy_array(tcx.resolutions(()).proc_macros.iter().map(|p| p.local_def_index));
let spans = self.tcx.sess.parse_sess.proc_macro_quoted_spans();
for (i, span) in spans.into_iter().enumerate() {
let span = self.lazy(span);
self.tables.proc_macro_quoted_spans.set(i, span);
}
self.tables.opt_def_kind.set(LOCAL_CRATE.as_def_id().index, DefKind::Mod);
record!(self.tables.def_span[LOCAL_CRATE.as_def_id()] <- tcx.def_span(LOCAL_CRATE.as_def_id()));
self.encode_attrs(LOCAL_CRATE.as_def_id().expect_local());
let vis = tcx.local_visibility(CRATE_DEF_ID).map_id(|def_id| def_id.local_def_index);
record!(self.tables.visibility[LOCAL_CRATE.as_def_id()] <- vis);
if let Some(stability) = stability {
record!(self.tables.lookup_stability[LOCAL_CRATE.as_def_id()] <- stability);
}
self.encode_deprecation(LOCAL_CRATE.as_def_id());
// Normally, this information is encoded when we walk the items
// defined in this crate. However, we skip doing that for proc-macro crates,
// so we manually encode just the information that we need
for &proc_macro in &tcx.resolutions(()).proc_macros {
let id = proc_macro;
let proc_macro = hir.local_def_id_to_hir_id(proc_macro);
let mut name = hir.name(proc_macro);
let span = hir.span(proc_macro);
// Proc-macros may have attributes like `#[allow_internal_unstable]`,
// so downstream crates need access to them.
let attrs = hir.attrs(proc_macro);
let macro_kind = if tcx.sess.contains_name(attrs, sym::proc_macro) {
MacroKind::Bang
} else if tcx.sess.contains_name(attrs, sym::proc_macro_attribute) {
MacroKind::Attr
} else if let Some(attr) = tcx.sess.find_by_name(attrs, sym::proc_macro_derive) {
// This unwrap chain should have been checked by the proc-macro harness.
name = attr.meta_item_list().unwrap()[0]
.meta_item()
.unwrap()
.ident()
.unwrap()
.name;
MacroKind::Derive
} else {
bug!("Unknown proc-macro type for item {:?}", id);
};
let mut def_key = self.tcx.hir().def_key(id);
def_key.disambiguated_data.data = DefPathData::MacroNs(name);
let def_id = id.to_def_id();
self.tables.opt_def_kind.set(def_id.index, DefKind::Macro(macro_kind));
self.tables.proc_macro.set(def_id.index, macro_kind);
self.encode_attrs(id);
record!(self.tables.def_keys[def_id] <- def_key);
record!(self.tables.def_ident_span[def_id] <- span);
record!(self.tables.def_span[def_id] <- span);
record!(self.tables.visibility[def_id] <- ty::Visibility::Public);
if let Some(stability) = stability {
record!(self.tables.lookup_stability[def_id] <- stability);
}
}
Some(ProcMacroData { proc_macro_decls_static, stability, macros })
} else {
None
}
}
fn encode_debugger_visualizers(&mut self) -> LazyArray<DebuggerVisualizerFile> {
empty_proc_macro!(self);
self.lazy_array(self.tcx.debugger_visualizers(LOCAL_CRATE).iter())
}
fn encode_crate_deps(&mut self) -> LazyArray<CrateDep> {
empty_proc_macro!(self);
let deps = self
.tcx
.crates(())
.iter()
.map(|&cnum| {
let dep = CrateDep {
name: self.tcx.crate_name(cnum),
hash: self.tcx.crate_hash(cnum),
host_hash: self.tcx.crate_host_hash(cnum),
kind: self.tcx.dep_kind(cnum),
extra_filename: self.tcx.extra_filename(cnum).clone(),
};
(cnum, dep)
})
.collect::<Vec<_>>();
{
// Sanity-check the crate numbers
let mut expected_cnum = 1;
for &(n, _) in &deps {
assert_eq!(n, CrateNum::new(expected_cnum));
expected_cnum += 1;
}
}
// We're just going to write a list of crate 'name-hash-version's, with
// the assumption that they are numbered 1 to n.
// FIXME (#2166): This is not nearly enough to support correct versioning
// but is enough to get transitive crate dependencies working.
self.lazy_array(deps.iter().map(|&(_, ref dep)| dep))
}
fn encode_lib_features(&mut self) -> LazyArray<(Symbol, Option<Symbol>)> {
empty_proc_macro!(self);
let tcx = self.tcx;
let lib_features = tcx.lib_features(());
self.lazy_array(lib_features.to_vec())
}
fn encode_stability_implications(&mut self) -> LazyArray<(Symbol, Symbol)> {
empty_proc_macro!(self);
let tcx = self.tcx;
let implications = tcx.stability_implications(LOCAL_CRATE);
self.lazy_array(implications.iter().map(|(k, v)| (*k, *v)))
}
fn encode_diagnostic_items(&mut self) -> LazyArray<(Symbol, DefIndex)> {
empty_proc_macro!(self);
let tcx = self.tcx;
let diagnostic_items = &tcx.diagnostic_items(LOCAL_CRATE).name_to_id;
self.lazy_array(diagnostic_items.iter().map(|(&name, def_id)| (name, def_id.index)))
}
fn encode_lang_items(&mut self) -> LazyArray<(DefIndex, LangItem)> {
empty_proc_macro!(self);
let lang_items = self.tcx.lang_items().iter();
self.lazy_array(lang_items.filter_map(|(lang_item, def_id)| {
def_id.as_local().map(|id| (id.local_def_index, lang_item))
}))
}
fn encode_lang_items_missing(&mut self) -> LazyArray<LangItem> {
empty_proc_macro!(self);
let tcx = self.tcx;
self.lazy_array(&tcx.lang_items().missing)
}
fn encode_traits(&mut self) -> LazyArray<DefIndex> {
empty_proc_macro!(self);
self.lazy_array(self.tcx.traits_in_crate(LOCAL_CRATE).iter().map(|def_id| def_id.index))
}
/// Encodes an index, mapping each trait to its (local) implementations.
fn encode_impls(&mut self) -> LazyArray<TraitImpls> {
debug!("EncodeContext::encode_traits_and_impls()");
empty_proc_macro!(self);
let tcx = self.tcx;
let mut fx_hash_map: FxHashMap<DefId, Vec<(DefIndex, Option<SimplifiedType>)>> =
FxHashMap::default();
for id in tcx.hir().items() {
if matches!(tcx.def_kind(id.owner_id), DefKind::Impl) {
if let Some(trait_ref) = tcx.impl_trait_ref(id.owner_id) {
let simplified_self_ty = fast_reject::simplify_type(
self.tcx,
trait_ref.self_ty(),
TreatParams::AsInfer,
);
fx_hash_map
.entry(trait_ref.def_id)
.or_default()
.push((id.owner_id.def_id.local_def_index, simplified_self_ty));
}
}
}
let mut all_impls: Vec<_> = fx_hash_map.into_iter().collect();
// Bring everything into deterministic order for hashing
all_impls.sort_by_cached_key(|&(trait_def_id, _)| tcx.def_path_hash(trait_def_id));
let all_impls: Vec<_> = all_impls
.into_iter()
.map(|(trait_def_id, mut impls)| {
// Bring everything into deterministic order for hashing
impls.sort_by_cached_key(|&(index, _)| {
tcx.hir().def_path_hash(LocalDefId { local_def_index: index })
});
TraitImpls {
trait_id: (trait_def_id.krate.as_u32(), trait_def_id.index),
impls: self.lazy_array(&impls),
}
})
.collect();
self.lazy_array(&all_impls)
}
fn encode_incoherent_impls(&mut self) -> LazyArray<IncoherentImpls> {
debug!("EncodeContext::encode_traits_and_impls()");
empty_proc_macro!(self);
let tcx = self.tcx;
let mut all_impls: Vec<_> = tcx.crate_inherent_impls(()).incoherent_impls.iter().collect();
tcx.with_stable_hashing_context(|mut ctx| {
all_impls.sort_by_cached_key(|&(&simp, _)| {
let mut hasher = StableHasher::new();
simp.hash_stable(&mut ctx, &mut hasher);
hasher.finish::<Fingerprint>()
})
});
let all_impls: Vec<_> = all_impls
.into_iter()
.map(|(&simp, impls)| {
let mut impls: Vec<_> =
impls.into_iter().map(|def_id| def_id.local_def_index).collect();
impls.sort_by_cached_key(|&local_def_index| {
tcx.hir().def_path_hash(LocalDefId { local_def_index })
});
IncoherentImpls { self_ty: simp, impls: self.lazy_array(impls) }
})
.collect();
self.lazy_array(&all_impls)
}
// Encodes all symbols exported from this crate into the metadata.
//
// This pass is seeded off the reachability list calculated in the
// middle::reachable module but filters out items that either don't have a
// symbol associated with them (they weren't translated) or if they're an FFI
// definition (as that's not defined in this crate).
fn encode_exported_symbols(
&mut self,
exported_symbols: &[(ExportedSymbol<'tcx>, SymbolExportInfo)],
) -> LazyArray<(ExportedSymbol<'static>, SymbolExportInfo)> {
empty_proc_macro!(self);
// The metadata symbol name is special. It should not show up in
// downstream crates.
let metadata_symbol_name = SymbolName::new(self.tcx, &metadata_symbol_name(self.tcx));
self.lazy_array(
exported_symbols
.iter()
.filter(|&&(ref exported_symbol, _)| match *exported_symbol {
ExportedSymbol::NoDefId(symbol_name) => symbol_name != metadata_symbol_name,
_ => true,
})
.cloned(),
)
}
fn encode_dylib_dependency_formats(&mut self) -> LazyArray<Option<LinkagePreference>> {
empty_proc_macro!(self);
let formats = self.tcx.dependency_formats(());
for (ty, arr) in formats.iter() {
if *ty != CrateType::Dylib {
continue;
}
return self.lazy_array(arr.iter().map(|slot| match *slot {
Linkage::NotLinked | Linkage::IncludedFromDylib => None,
Linkage::Dynamic => Some(LinkagePreference::RequireDynamic),
Linkage::Static => Some(LinkagePreference::RequireStatic),
}));
}
LazyArray::empty()
}
fn encode_info_for_foreign_item(&mut self, def_id: DefId, nitem: &hir::ForeignItem<'_>) {
let tcx = self.tcx;
debug!("EncodeContext::encode_info_for_foreign_item({:?})", def_id);
match nitem.kind {
hir::ForeignItemKind::Fn(_, ref names, _) => {
self.tables.asyncness.set(def_id.index, hir::IsAsync::NotAsync);
record_array!(self.tables.fn_arg_names[def_id] <- *names);
let constness = if self.tcx.is_const_fn_raw(def_id) {
hir::Constness::Const
} else {
hir::Constness::NotConst
};
self.tables.constness.set(def_id.index, constness);
record!(self.tables.fn_sig[def_id] <- tcx.fn_sig(def_id));
}
hir::ForeignItemKind::Static(..) | hir::ForeignItemKind::Type => {}
}
if let hir::ForeignItemKind::Fn(..) = nitem.kind {
if tcx.is_intrinsic(def_id) {
self.tables.is_intrinsic.set(def_id.index, ());
}
}
}
}
// FIXME(eddyb) make metadata encoding walk over all definitions, instead of HIR.
impl<'a, 'tcx> Visitor<'tcx> for EncodeContext<'a, 'tcx> {
type NestedFilter = nested_filter::OnlyBodies;
fn nested_visit_map(&mut self) -> Self::Map {
self.tcx.hir()
}
fn visit_expr(&mut self, ex: &'tcx hir::Expr<'tcx>) {
intravisit::walk_expr(self, ex);
self.encode_info_for_expr(ex);
}
fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
intravisit::walk_item(self, item);
match item.kind {
hir::ItemKind::ExternCrate(_) | hir::ItemKind::Use(..) => {} // ignore these
_ => self.encode_info_for_item(item.owner_id.to_def_id(), item),
}
}
fn visit_foreign_item(&mut self, ni: &'tcx hir::ForeignItem<'tcx>) {
intravisit::walk_foreign_item(self, ni);
self.encode_info_for_foreign_item(ni.owner_id.to_def_id(), ni);
}
fn visit_generics(&mut self, generics: &'tcx hir::Generics<'tcx>) {
intravisit::walk_generics(self, generics);
self.encode_info_for_generics(generics);
}
}
impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
fn encode_info_for_generics(&mut self, generics: &hir::Generics<'tcx>) {
for param in generics.params {
match param.kind {
hir::GenericParamKind::Lifetime { .. } | hir::GenericParamKind::Type { .. } => {}
hir::GenericParamKind::Const { ref default, .. } => {
let def_id = param.def_id.to_def_id();
if default.is_some() {
record!(self.tables.const_param_default[def_id] <- self.tcx.const_param_default(def_id))
}
}
}
}
}
fn encode_info_for_expr(&mut self, expr: &hir::Expr<'_>) {
if let hir::ExprKind::Closure(closure) = expr.kind {
self.encode_info_for_closure(closure.def_id);
}
}
}
/// Used to prefetch queries which will be needed later by metadata encoding.
/// Only a subset of the queries are actually prefetched to keep this code smaller.
fn prefetch_mir(tcx: TyCtxt<'_>) {
if !tcx.sess.opts.output_types.should_codegen() {
// We won't emit MIR, so don't prefetch it.
return;
}
par_iter(tcx.mir_keys(())).for_each(|&def_id| {
let (encode_const, encode_opt) = should_encode_mir(tcx, def_id);
if encode_const {
tcx.ensure().mir_for_ctfe(def_id);
}
if encode_opt {
tcx.ensure().optimized_mir(def_id);
}
if encode_opt || encode_const {
tcx.ensure().promoted_mir(def_id);
}
})
}
// NOTE(eddyb) The following comment was preserved for posterity, even
// though it's no longer relevant as EBML (which uses nested & tagged
// "documents") was replaced with a scheme that can't go out of bounds.
//
// And here we run into yet another obscure archive bug: in which metadata
// loaded from archives may have trailing garbage bytes. Awhile back one of
// our tests was failing sporadically on the macOS 64-bit builders (both nopt
// and opt) by having ebml generate an out-of-bounds panic when looking at
// metadata.
//
// Upon investigation it turned out that the metadata file inside of an rlib
// (and ar archive) was being corrupted. Some compilations would generate a
// metadata file which would end in a few extra bytes, while other
// compilations would not have these extra bytes appended to the end. These
// extra bytes were interpreted by ebml as an extra tag, so they ended up
// being interpreted causing the out-of-bounds.
//
// The root cause of why these extra bytes were appearing was never
// discovered, and in the meantime the solution we're employing is to insert
// the length of the metadata to the start of the metadata. Later on this
// will allow us to slice the metadata to the precise length that we just
// generated regardless of trailing bytes that end up in it.
pub struct EncodedMetadata {
// The declaration order matters because `mmap` should be dropped before `_temp_dir`.
mmap: Option<Mmap>,
// We need to carry MaybeTempDir to avoid deleting the temporary
// directory while accessing the Mmap.
_temp_dir: Option<MaybeTempDir>,
}
impl EncodedMetadata {
#[inline]
pub fn from_path(path: PathBuf, temp_dir: Option<MaybeTempDir>) -> std::io::Result<Self> {
let file = std::fs::File::open(&path)?;
let file_metadata = file.metadata()?;
if file_metadata.len() == 0 {
return Ok(Self { mmap: None, _temp_dir: None });
}
let mmap = unsafe { Some(Mmap::map(file)?) };
Ok(Self { mmap, _temp_dir: temp_dir })
}
#[inline]
pub fn raw_data(&self) -> &[u8] {
self.mmap.as_deref().unwrap_or_default()
}
}
impl<S: Encoder> Encodable<S> for EncodedMetadata {
fn encode(&self, s: &mut S) {
let slice = self.raw_data();
slice.encode(s)
}
}
impl<D: Decoder> Decodable<D> for EncodedMetadata {
fn decode(d: &mut D) -> Self {
let len = d.read_usize();
let mmap = if len > 0 {
let mut mmap = MmapMut::map_anon(len).unwrap();
for _ in 0..len {
(&mut mmap[..]).write(&[d.read_u8()]).unwrap();
}
mmap.flush().unwrap();
Some(mmap.make_read_only().unwrap())
} else {
None
};
Self { mmap, _temp_dir: None }
}
}
pub fn encode_metadata(tcx: TyCtxt<'_>, path: &Path) {
let _prof_timer = tcx.prof.verbose_generic_activity("generate_crate_metadata");
// Since encoding metadata is not in a query, and nothing is cached,
// there's no need to do dep-graph tracking for any of it.
tcx.dep_graph.assert_ignored();
join(
|| encode_metadata_impl(tcx, path),
|| {
if tcx.sess.threads() == 1 {
return;
}
// Prefetch some queries used by metadata encoding.
// This is not necessary for correctness, but is only done for performance reasons.
// It can be removed if it turns out to cause trouble or be detrimental to performance.
join(|| prefetch_mir(tcx), || tcx.exported_symbols(LOCAL_CRATE));
},
);
}
fn encode_metadata_impl(tcx: TyCtxt<'_>, path: &Path) {
let mut encoder = opaque::FileEncoder::new(path)
.unwrap_or_else(|err| tcx.sess.emit_fatal(FailCreateFileEncoder { err }));
encoder.emit_raw_bytes(METADATA_HEADER);
// Will be filled with the root position after encoding everything.
encoder.emit_raw_bytes(&[0, 0, 0, 0]);
let source_map_files = tcx.sess.source_map().files();
let source_file_cache = (source_map_files[0].clone(), 0);
let required_source_files = Some(FxIndexSet::default());
drop(source_map_files);
let hygiene_ctxt = HygieneEncodeContext::default();
let mut ecx = EncodeContext {
opaque: encoder,
tcx,
feat: tcx.features(),
tables: Default::default(),
lazy_state: LazyState::NoNode,
type_shorthands: Default::default(),
predicate_shorthands: Default::default(),
source_file_cache,
interpret_allocs: Default::default(),
required_source_files,
is_proc_macro: tcx.sess.crate_types().contains(&CrateType::ProcMacro),
hygiene_ctxt: &hygiene_ctxt,
symbol_table: Default::default(),
};
// Encode the rustc version string in a predictable location.
rustc_version().encode(&mut ecx);
// Encode all the entries and extra information in the crate,
// culminating in the `CrateRoot` which points to all of it.
let root = ecx.encode_crate_root();
ecx.opaque.flush();
let mut file = ecx.opaque.file();
// We will return to this position after writing the root position.
let pos_before_seek = file.stream_position().unwrap();
// Encode the root position.
let header = METADATA_HEADER.len();
file.seek(std::io::SeekFrom::Start(header as u64))
.unwrap_or_else(|err| tcx.sess.emit_fatal(FailSeekFile { err }));
let pos = root.position.get();
file.write_all(&[(pos >> 24) as u8, (pos >> 16) as u8, (pos >> 8) as u8, (pos >> 0) as u8])
.unwrap_or_else(|err| tcx.sess.emit_fatal(FailWriteFile { err }));
// Return to the position where we are before writing the root position.
file.seek(std::io::SeekFrom::Start(pos_before_seek)).unwrap();
// Record metadata size for self-profiling
tcx.prof.artifact_size(
"crate_metadata",
"crate_metadata",
file.metadata().unwrap().len() as u64,
);
}
pub fn provide(providers: &mut Providers) {
*providers = Providers {
traits_in_crate: |tcx, cnum| {
assert_eq!(cnum, LOCAL_CRATE);
let mut traits = Vec::new();
for id in tcx.hir().items() {
if matches!(tcx.def_kind(id.owner_id), DefKind::Trait | DefKind::TraitAlias) {
traits.push(id.owner_id.to_def_id())
}
}
// Bring everything into deterministic order.
traits.sort_by_cached_key(|&def_id| tcx.def_path_hash(def_id));
tcx.arena.alloc_slice(&traits)
},
..*providers
}
}
Reference in a new issue View git blame Copy permalink