Auto merge of #136471 - safinaskar:parallel, r=SparrowLii

tree-wide: parallel: Fully removed all `Lrc`, replaced with `Arc`

tree-wide: parallel: Fully removed all `Lrc`, replaced with `Arc`

This is continuation of https://github.com/rust-lang/rust/pull/132282 .

I'm pretty sure I did everything right. In particular, I searched all occurrences of `Lrc` in submodules and made sure that they don't need replacement.

There are other possibilities, through.

We can define `enum Lrc<T> { Rc(Rc<T>), Arc(Arc<T>) }`. Or we can make `Lrc` a union and on every clone we can read from special thread-local variable. Or we can add a generic parameter to `Lrc` and, yes, this parameter will be everywhere across all codebase.

So, if you think we should take some alternative approach, then don't merge this PR. But if it is decided to stick with `Arc`, then, please, merge.

cc "Parallel Rustc Front-end" ( https://github.com/rust-lang/rust/issues/113349 )

r? SparrowLii

`@rustbot` label WG-compiler-parallel

2 files changed, 21 insertions, 22 deletions

diff --git a/compiler/rustc_session/src/parse.rs b/compiler/rustc_session/src/parse.rs
index abfd3efc611..d4db05ce139 100644
--- a/compiler/rustc_session/src/parse.rs
+++ b/compiler/rustc_session/src/parse.rs
@@ -2,11 +2,12 @@
 //! It also serves as an input to the parser itself.
 
 use std::str;
+use std::sync::Arc;
 
 use rustc_ast::attr::AttrIdGenerator;
 use rustc_ast::node_id::NodeId;
 use rustc_data_structures::fx::{FxHashMap, FxIndexMap, FxIndexSet};
-use rustc_data_structures::sync::{AppendOnlyVec, Lock, Lrc};
+use rustc_data_structures::sync::{AppendOnlyVec, Lock};
 use rustc_errors::emitter::{HumanEmitter, SilentEmitter, stderr_destination};
 use rustc_errors::{
     ColorConfig, Diag, DiagCtxt, DiagCtxtHandle, DiagMessage, EmissionGuarantee, MultiSpan,
@@ -218,7 +219,7 @@ pub struct ParseSess {
     /// should be. Useful to avoid bad tokenization when encountering emoji. We group them to
     /// provide a single error per unique incorrect identifier.
     pub bad_unicode_identifiers: Lock<FxIndexMap<Symbol, Vec<Span>>>,
-    source_map: Lrc<SourceMap>,
+    source_map: Arc<SourceMap>,
     pub buffered_lints: Lock<Vec<BufferedEarlyLint>>,
     /// Contains the spans of block expressions that could have been incomplete based on the
     /// operation token that followed it, but that the parser cannot identify without further
@@ -243,16 +244,16 @@ impl ParseSess {
     /// Used for testing.
     pub fn new(locale_resources: Vec<&'static str>) -> Self {
         let fallback_bundle = fallback_fluent_bundle(locale_resources, false);
-        let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
+        let sm = Arc::new(SourceMap::new(FilePathMapping::empty()));
         let emitter = Box::new(
             HumanEmitter::new(stderr_destination(ColorConfig::Auto), fallback_bundle)
-                .sm(Some(Lrc::clone(&sm))),
+                .sm(Some(Arc::clone(&sm))),
         );
         let dcx = DiagCtxt::new(emitter);
         ParseSess::with_dcx(dcx, sm)
     }
 
-    pub fn with_dcx(dcx: DiagCtxt, source_map: Lrc<SourceMap>) -> Self {
+    pub fn with_dcx(dcx: DiagCtxt, source_map: Arc<SourceMap>) -> Self {
         Self {
             dcx,
             unstable_features: UnstableFeatures::from_environment(None),
@@ -281,7 +282,7 @@ impl ParseSess {
         emit_fatal_diagnostic: bool,
     ) -> Self {
         let fallback_bundle = fallback_fluent_bundle(locale_resources, false);
-        let sm = Lrc::new(SourceMap::new(FilePathMapping::empty()));
+        let sm = Arc::new(SourceMap::new(FilePathMapping::empty()));
         let fatal_emitter =
             Box::new(HumanEmitter::new(stderr_destination(ColorConfig::Auto), fallback_bundle));
         let dcx = DiagCtxt::new(Box::new(SilentEmitter {
@@ -298,8 +299,8 @@ impl ParseSess {
         &self.source_map
     }
 
-    pub fn clone_source_map(&self) -> Lrc<SourceMap> {
-        Lrc::clone(&self.source_map)
+    pub fn clone_source_map(&self) -> Arc<SourceMap> {
+        Arc::clone(&self.source_map)
     }
 
     pub fn buffer_lint(
diff --git a/compiler/rustc_session/src/session.rs b/compiler/rustc_session/src/session.rs
index c9bb42bdfa1..1a3e80d6659 100644
--- a/compiler/rustc_session/src/session.rs
+++ b/compiler/rustc_session/src/session.rs
@@ -9,9 +9,7 @@ use std::{env, fmt, io};
 use rustc_data_structures::flock;
 use rustc_data_structures::fx::{FxHashMap, FxIndexSet};
 use rustc_data_structures::profiling::{SelfProfiler, SelfProfilerRef};
-use rustc_data_structures::sync::{
-    DynSend, DynSync, Lock, Lrc, MappedReadGuard, ReadGuard, RwLock,
-};
+use rustc_data_structures::sync::{DynSend, DynSync, Lock, MappedReadGuard, ReadGuard, RwLock};
 use rustc_errors::annotate_snippet_emitter_writer::AnnotateSnippetEmitter;
 use rustc_errors::codes::*;
 use rustc_errors::emitter::{
@@ -138,8 +136,8 @@ pub struct Session {
     pub target: Target,
     pub host: Target,
     pub opts: config::Options,
-    pub host_tlib_path: Lrc<SearchPath>,
-    pub target_tlib_path: Lrc<SearchPath>,
+    pub host_tlib_path: Arc<SearchPath>,
+    pub target_tlib_path: Arc<SearchPath>,
     pub psess: ParseSess,
     pub sysroot: PathBuf,
     /// Input, input file path and output file path to this compilation process.
@@ -154,7 +152,7 @@ pub struct Session {
     pub code_stats: CodeStats,
 
     /// This only ever stores a `LintStore` but we don't want a dependency on that type here.
-    pub lint_store: Option<Lrc<dyn LintStoreMarker>>,
+    pub lint_store: Option<Arc<dyn LintStoreMarker>>,
 
     /// Cap lint level specified by a driver specifically.
     pub driver_lint_caps: FxHashMap<lint::LintId, lint::Level>,
@@ -885,8 +883,8 @@ impl Session {
 #[allow(rustc::bad_opt_access)]
 fn default_emitter(
     sopts: &config::Options,
-    source_map: Lrc<SourceMap>,
-    bundle: Option<Lrc<FluentBundle>>,
+    source_map: Arc<SourceMap>,
+    bundle: Option<Arc<FluentBundle>>,
     fallback_bundle: LazyFallbackBundle,
 ) -> Box<DynEmitter> {
     let macro_backtrace = sopts.unstable_opts.macro_backtrace;
@@ -970,7 +968,7 @@ pub fn build_session(
     early_dcx: EarlyDiagCtxt,
     sopts: config::Options,
     io: CompilerIO,
-    bundle: Option<Lrc<rustc_errors::FluentBundle>>,
+    bundle: Option<Arc<rustc_errors::FluentBundle>>,
     registry: rustc_errors::registry::Registry,
     fluent_resources: Vec<&'static str>,
     driver_lint_caps: FxHashMap<lint::LintId, lint::Level>,
@@ -1005,7 +1003,7 @@ pub fn build_session(
         sopts.unstable_opts.translate_directionality_markers,
     );
     let source_map = rustc_span::source_map::get_source_map().unwrap();
-    let emitter = default_emitter(&sopts, Lrc::clone(&source_map), bundle, fallback_bundle);
+    let emitter = default_emitter(&sopts, Arc::clone(&source_map), bundle, fallback_bundle);
 
     let mut dcx = DiagCtxt::new(emitter)
         .with_flags(sopts.unstable_opts.dcx_flags(can_emit_warnings))
@@ -1045,13 +1043,13 @@ pub fn build_session(
 
     let host_triple = config::host_tuple();
     let target_triple = sopts.target_triple.tuple();
-    let host_tlib_path = Lrc::new(SearchPath::from_sysroot_and_triple(&sysroot, host_triple));
+    let host_tlib_path = Arc::new(SearchPath::from_sysroot_and_triple(&sysroot, host_triple));
     let target_tlib_path = if host_triple == target_triple {
         // Use the same `SearchPath` if host and target triple are identical to avoid unnecessary
         // rescanning of the target lib path and an unnecessary allocation.
-        Lrc::clone(&host_tlib_path)
+        Arc::clone(&host_tlib_path)
     } else {
-        Lrc::new(SearchPath::from_sysroot_and_triple(&sysroot, target_triple))
+        Arc::new(SearchPath::from_sysroot_and_triple(&sysroot, target_triple))
     };
 
     let prof = SelfProfilerRef::new(
@@ -1446,7 +1444,7 @@ fn mk_emitter(output: ErrorOutputType) -> Box<DynEmitter> {
         config::ErrorOutputType::Json { pretty, json_rendered, color_config } => {
             Box::new(JsonEmitter::new(
                 Box::new(io::BufWriter::new(io::stderr())),
-                Some(Lrc::new(SourceMap::new(FilePathMapping::empty()))),
+                Some(Arc::new(SourceMap::new(FilePathMapping::empty()))),
                 fallback_bundle,
                 pretty,
                 json_rendered,