Auto merge of #142689 - Urgau:rollup-4ho6835, r=Urgau

Rollup of 6 pull requests

Successful merges:

 - rust-lang/rust#135656 (Add `-Z hint-mostly-unused` to tell rustc that most of a crate will go unused)
 - rust-lang/rust#138237 (Get rid of `EscapeDebugInner`.)
 - rust-lang/rust#141614 (lint direct use of rustc_type_ir )
 - rust-lang/rust#142123 (Implement initial support for timing sections (`--json=timings`))
 - rust-lang/rust#142377 (Try unremapping compiler sources)
 - rust-lang/rust#142674 (remove duplicate crash test)

r? `@ghost`
`@rustbot` modify labels: rollup

3 files changed, 52 insertions, 7 deletions

diff --git a/compiler/rustc_session/src/config.rs b/compiler/rustc_session/src/config.rs
index 04ca0b75c31..87e4b0a17aa 100644
--- a/compiler/rustc_session/src/config.rs
+++ b/compiler/rustc_session/src/config.rs
@@ -1364,8 +1364,10 @@ impl Default for Options {
             cli_forced_local_thinlto_off: false,
             remap_path_prefix: Vec::new(),
             real_rust_source_base_dir: None,
+            real_rustc_dev_source_base_dir: None,
             edition: DEFAULT_EDITION,
             json_artifact_notifications: false,
+            json_timings: false,
             json_unused_externs: JsonUnusedExterns::No,
             json_future_incompat: false,
             pretty: None,
@@ -1880,6 +1882,9 @@ pub struct JsonConfig {
     pub json_rendered: HumanReadableErrorType,
     pub json_color: ColorConfig,
     json_artifact_notifications: bool,
+    /// Output start and end timestamps of several high-level compilation sections
+    /// (frontend, backend, linker).
+    json_timings: bool,
     pub json_unused_externs: JsonUnusedExterns,
     json_future_incompat: bool,
 }
@@ -1921,6 +1926,7 @@ pub fn parse_json(early_dcx: &EarlyDiagCtxt, matches: &getopts::Matches) -> Json
     let mut json_artifact_notifications = false;
     let mut json_unused_externs = JsonUnusedExterns::No;
     let mut json_future_incompat = false;
+    let mut json_timings = false;
     for option in matches.opt_strs("json") {
         // For now conservatively forbid `--color` with `--json` since `--json`
         // won't actually be emitting any colors and anything colorized is
@@ -1937,6 +1943,7 @@ pub fn parse_json(early_dcx: &EarlyDiagCtxt, matches: &getopts::Matches) -> Json
                 }
                 "diagnostic-rendered-ansi" => json_color = ColorConfig::Always,
                 "artifacts" => json_artifact_notifications = true,
+                "timings" => json_timings = true,
                 "unused-externs" => json_unused_externs = JsonUnusedExterns::Loud,
                 "unused-externs-silent" => json_unused_externs = JsonUnusedExterns::Silent,
                 "future-incompat" => json_future_incompat = true,
@@ -1949,6 +1956,7 @@ pub fn parse_json(early_dcx: &EarlyDiagCtxt, matches: &getopts::Matches) -> Json
         json_rendered,
         json_color,
         json_artifact_notifications,
+        json_timings,
         json_unused_externs,
         json_future_incompat,
     }
@@ -2476,6 +2484,7 @@ pub fn build_session_options(early_dcx: &mut EarlyDiagCtxt, matches: &getopts::M
         json_rendered,
         json_color,
         json_artifact_notifications,
+        json_timings,
         json_unused_externs,
         json_future_incompat,
     } = parse_json(early_dcx, matches);
@@ -2497,6 +2506,10 @@ pub fn build_session_options(early_dcx: &mut EarlyDiagCtxt, matches: &getopts::M
     let mut unstable_opts = UnstableOptions::build(early_dcx, matches, &mut target_modifiers);
     let (lint_opts, describe_lints, lint_cap) = get_cmd_lint_options(early_dcx, matches);
 
+    if !unstable_opts.unstable_options && json_timings {
+        early_dcx.early_fatal("--json=timings is unstable and requires using `-Zunstable-options`");
+    }
+
     check_error_format_stability(early_dcx, &unstable_opts, error_format);
 
     let output_types = parse_output_types(early_dcx, &unstable_opts, matches);
@@ -2701,9 +2714,8 @@ pub fn build_session_options(early_dcx: &mut EarlyDiagCtxt, matches: &getopts::M
 
     let sysroot = filesearch::materialize_sysroot(sysroot_opt);
 
-    let real_rust_source_base_dir = {
-        // This is the location used by the `rust-src` `rustup` component.
-        let mut candidate = sysroot.join("lib/rustlib/src/rust");
+    let real_source_base_dir = |suffix: &str, confirm: &str| {
+        let mut candidate = sysroot.join(suffix);
         if let Ok(metadata) = candidate.symlink_metadata() {
             // Replace the symlink bootstrap creates, with its destination.
             // We could try to use `fs::canonicalize` instead, but that might
@@ -2716,9 +2728,17 @@ pub fn build_session_options(early_dcx: &mut EarlyDiagCtxt, matches: &getopts::M
         }
 
         // Only use this directory if it has a file we can expect to always find.
-        candidate.join("library/std/src/lib.rs").is_file().then_some(candidate)
+        candidate.join(confirm).is_file().then_some(candidate)
     };
 
+    let real_rust_source_base_dir =
+        // This is the location used by the `rust-src` `rustup` component.
+        real_source_base_dir("lib/rustlib/src/rust", "library/std/src/lib.rs");
+
+    let real_rustc_dev_source_base_dir =
+        // This is the location used by the `rustc-dev` `rustup` component.
+        real_source_base_dir("lib/rustlib/rustc-src/rust", "compiler/rustc/src/main.rs");
+
     let mut search_paths = vec![];
     for s in &matches.opt_strs("L") {
         search_paths.push(SearchPath::from_cli_opt(
@@ -2772,8 +2792,10 @@ pub fn build_session_options(early_dcx: &mut EarlyDiagCtxt, matches: &getopts::M
         cli_forced_local_thinlto_off: disable_local_thinlto,
         remap_path_prefix,
         real_rust_source_base_dir,
+        real_rustc_dev_source_base_dir,
         edition,
         json_artifact_notifications,
+        json_timings,
         json_unused_externs,
         json_future_incompat,
         pretty,
diff --git a/compiler/rustc_session/src/options.rs b/compiler/rustc_session/src/options.rs
index 9ca405333f4..31b4237d3b2 100644
--- a/compiler/rustc_session/src/options.rs
+++ b/compiler/rustc_session/src/options.rs
@@ -395,21 +395,35 @@ top_level_options!(
 
         /// Remap source path prefixes in all output (messages, object files, debug, etc.).
         remap_path_prefix: Vec<(PathBuf, PathBuf)> [TRACKED_NO_CRATE_HASH],
-        /// Base directory containing the `src/` for the Rust standard library, and
-        /// potentially `rustc` as well, if we can find it. Right now it's always
-        /// `$sysroot/lib/rustlib/src/rust` (i.e. the `rustup` `rust-src` component).
+
+        /// Base directory containing the `library/` directory for the Rust standard library.
+        /// Right now it's always `$sysroot/lib/rustlib/src/rust`
+        /// (i.e. the `rustup` `rust-src` component).
         ///
         /// This directory is what the virtual `/rustc/$hash` is translated back to,
         /// if Rust was built with path remapping to `/rustc/$hash` enabled
         /// (the `rust.remap-debuginfo` option in `bootstrap.toml`).
         real_rust_source_base_dir: Option<PathBuf> [TRACKED_NO_CRATE_HASH],
 
+        /// Base directory containing the `compiler/` directory for the rustc sources.
+        /// Right now it's always `$sysroot/lib/rustlib/rustc-src/rust`
+        /// (i.e. the `rustup` `rustc-dev` component).
+        ///
+        /// This directory is what the virtual `/rustc-dev/$hash` is translated back to,
+        /// if Rust was built with path remapping to `/rustc/$hash` enabled
+        /// (the `rust.remap-debuginfo` option in `bootstrap.toml`).
+        real_rustc_dev_source_base_dir: Option<PathBuf> [TRACKED_NO_CRATE_HASH],
+
         edition: Edition [TRACKED],
 
         /// `true` if we're emitting JSON blobs about each artifact produced
         /// by the compiler.
         json_artifact_notifications: bool [TRACKED],
 
+        /// `true` if we're emitting JSON timings with the start and end of
+        /// high-level compilation sections
+        json_timings: bool [UNTRACKED],
+
         /// `true` if we're emitting a JSON blob containing the unused externs
         json_unused_externs: JsonUnusedExterns [UNTRACKED],
 
@@ -2235,6 +2249,8 @@ options! {
         environment variable `RUSTC_GRAPHVIZ_FONT` (default: `Courier, monospace`)"),
     has_thread_local: Option<bool> = (None, parse_opt_bool, [TRACKED],
         "explicitly enable the `cfg(target_thread_local)` directive"),
+    hint_mostly_unused: bool = (false, parse_bool, [TRACKED],
+        "hint that most of this crate will go unused, to minimize work for uncalled functions"),
     human_readable_cgu_names: bool = (false, parse_bool, [TRACKED],
         "generate human-readable, predictable names for codegen units (default: no)"),
     identify_regions: bool = (false, parse_bool, [UNTRACKED],
diff --git a/compiler/rustc_session/src/session.rs b/compiler/rustc_session/src/session.rs
index b8b4518b14e..ca42c5a4256 100644
--- a/compiler/rustc_session/src/session.rs
+++ b/compiler/rustc_session/src/session.rs
@@ -18,6 +18,7 @@ use rustc_errors::emitter::{
     DynEmitter, HumanEmitter, HumanReadableErrorType, OutputTheme, stderr_destination,
 };
 use rustc_errors::json::JsonEmitter;
+use rustc_errors::timings::TimingSectionHandler;
 use rustc_errors::{
     Diag, DiagCtxt, DiagCtxtHandle, DiagMessage, Diagnostic, ErrorGuaranteed, FatalAbort,
     FluentBundle, LazyFallbackBundle, TerminalUrl, fallback_fluent_bundle,
@@ -156,6 +157,9 @@ pub struct Session {
     /// Used by `-Z self-profile`.
     pub prof: SelfProfilerRef,
 
+    /// Used to emit section timings events (enabled by `--json=timings`).
+    pub timings: TimingSectionHandler,
+
     /// Data about code being compiled, gathered during compilation.
     pub code_stats: CodeStats,
 
@@ -1126,6 +1130,8 @@ pub fn build_session(
         .as_ref()
         .map(|_| rng().next_u32().to_base_fixed_len(CASE_INSENSITIVE).to_string());
 
+    let timings = TimingSectionHandler::new(sopts.json_timings);
+
     let sess = Session {
         target,
         host,
@@ -1136,6 +1142,7 @@ pub fn build_session(
         io,
         incr_comp_session: RwLock::new(IncrCompSession::NotInitialized),
         prof,
+        timings,
         code_stats: Default::default(),
         lint_store: None,
         driver_lint_caps,