Auto merge of #64981 - tmandry:rollup-slfkhay, r=tmandry

Rollup of 11 pull requests

Successful merges:

 - #64649 (Avoid ICE on return outside of fn with literal array)
 - #64722 (Make all alt builders produce parallel-enabled compilers)
 - #64801 (Avoid `chain()` in `find_constraint_paths_between_regions()`.)
 - #64805 (Still more `ObligationForest` improvements.)
 - #64840 (SelfProfiler API refactoring and part one of event review)
 - #64885 (use try_fold instead of try_for_each to reduce compile time)
 - #64942 (Fix clippy warnings)
 - #64952 (Update cargo.)
 - #64974 (Fix zebra-striping in generic dataflow visualization)
 - #64978 (Fully clear `HandlerInner` in `Handler::reset_err_count`)
 - #64979 (Update books)

Failed merges:

 - #64959 (syntax: improve parameter without type suggestions)

r? @ghost

Cargo.lock

@@ -265,7 +265,7 @@ dependencies = [
 
 [[package]]
 name = "cargo"
-version = "0.40.0"
+version = "0.41.0"
 dependencies = [
  "atty",
  "bytesize",
@@ -600,7 +600,7 @@ checksum = "e7ca8a5221364ef15ce201e8ed2f609fc312682a8f4e0e3d4aa5879764e0fa3b"
 
 [[package]]
 name = "crates-io"
-version = "0.28.0"
+version = "0.29.0"
 dependencies = [
  "curl",
  "failure",
@@ -730,25 +730,24 @@ dependencies = [
 
 [[package]]
 name = "curl"
-version = "0.4.21"
+version = "0.4.24"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a85f2f95f2bd277d316d1aa8a477687ab4a6942258c7db7c89c187534669979c"
+checksum = "d08ad3cb89d076a36b0ce5749eec2c9964f70c0c58480ab6b75a91ec4fc206d8"
 dependencies = [
  "curl-sys",
- "kernel32-sys",
  "libc",
  "openssl-probe",
  "openssl-sys",
  "schannel",
  "socket2",
- "winapi 0.2.8",
+ "winapi 0.3.6",
 ]
 
 [[package]]
 name = "curl-sys"
-version = "0.4.18"
+version = "0.4.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9d91a0052d5b982887d8e829bee0faffc7218ea3c6ebd3d6c2c8f678a93c9a42"
+checksum = "2e9a9a4e417722876332136a00cacf92c2ceb331fab4b52b6a1ad16c6cd79255"
 dependencies = [
  "cc",
  "libc",

src/ci/run.sh

@@ -55,6 +55,9 @@ if [ "$DEPLOY$DEPLOY_ALT" = "1" ]; then
   if [ "$NO_LLVM_ASSERTIONS" = "1" ]; then
     RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --disable-llvm-assertions"
   elif [ "$DEPLOY_ALT" != "" ]; then
+    if [ "$NO_PARALLEL_COMPILER" = "" ]; then
+      RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.parallel-compiler"
+    fi
     RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --enable-llvm-assertions"
     RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set rust.verify-llvm-ir"
   fi

src/libarena/lib.rs

@@ -500,7 +500,7 @@ impl DroplessArena {
                 // though it was supposed to give us `len`
                 return slice::from_raw_parts_mut(mem, i);
             }
-            ptr::write(mem.offset(i as isize), value.unwrap());
+            ptr::write(mem.add(i), value.unwrap());
             i += 1;
         }
     }

src/libcore/iter/traits/iterator.rs

@@ -1859,14 +1859,13 @@ pub trait Iterator {
         Self: Sized, F: FnMut(Self::Item) -> bool
     {
         #[inline]
-        fn check<T>(mut f: impl FnMut(T) -> bool) -> impl FnMut(T) -> LoopState<(), ()> {
-            move |x| {
+        fn check<T>(mut f: impl FnMut(T) -> bool) -> impl FnMut((), T) -> LoopState<(), ()> {
+            move |(), x| {
                 if f(x) { LoopState::Continue(()) }
                 else { LoopState::Break(()) }
             }
         }
-
-        self.try_for_each(check(f)) == LoopState::Continue(())
+        self.try_fold((), check(f)) == LoopState::Continue(())
     }
 
     /// Tests if any element of the iterator matches a predicate.
@@ -1913,14 +1912,14 @@ pub trait Iterator {
         F: FnMut(Self::Item) -> bool
     {
         #[inline]
-        fn check<T>(mut f: impl FnMut(T) -> bool) -> impl FnMut(T) -> LoopState<(), ()> {
-            move |x| {
+        fn check<T>(mut f: impl FnMut(T) -> bool) -> impl FnMut((), T) -> LoopState<(), ()> {
+            move |(), x| {
                 if f(x) { LoopState::Break(()) }
                 else { LoopState::Continue(()) }
             }
         }
 
-        self.try_for_each(check(f)) == LoopState::Break(())
+        self.try_fold((), check(f)) == LoopState::Break(())
     }
 
     /// Searches for an element of an iterator that satisfies a predicate.
@@ -1972,14 +1971,16 @@ pub trait Iterator {
         P: FnMut(&Self::Item) -> bool,
     {
         #[inline]
-        fn check<T>(mut predicate: impl FnMut(&T) -> bool) -> impl FnMut(T) -> LoopState<(), T> {
-            move |x| {
+        fn check<T>(
+            mut predicate: impl FnMut(&T) -> bool
+        ) -> impl FnMut((), T) -> LoopState<(), T> {
+            move |(), x| {
                 if predicate(&x) { LoopState::Break(x) }
                 else { LoopState::Continue(()) }
             }
         }
 
-        self.try_for_each(check(predicate)).break_value()
+        self.try_fold((), check(predicate)).break_value()
     }
 
     /// Applies function to the elements of iterator and returns
@@ -2004,14 +2005,14 @@ pub trait Iterator {
         F: FnMut(Self::Item) -> Option<B>,
     {
         #[inline]
-        fn check<T, B>(mut f: impl FnMut(T) -> Option<B>) -> impl FnMut(T) -> LoopState<(), B> {
-            move |x| match f(x) {
+        fn check<T, B>(mut f: impl FnMut(T) -> Option<B>) -> impl FnMut((), T) -> LoopState<(), B> {
+            move |(), x| match f(x) {
                 Some(x) => LoopState::Break(x),
                 None => LoopState::Continue(()),
             }
         }
 
-        self.try_for_each(check(f)).break_value()
+        self.try_fold((), check(f)).break_value()
     }
 
     /// Searches for an element in an iterator, returning its index.

src/librustc/session/config.rs

@@ -805,6 +805,7 @@ macro_rules! options {
         pub const parse_list: Option<&str> = Some("a space-separated list of strings");
         pub const parse_opt_list: Option<&str> = Some("a space-separated list of strings");
         pub const parse_opt_comma_list: Option<&str> = Some("a comma-separated list of strings");
+        pub const parse_threads: Option<&str> = Some("a number");
         pub const parse_uint: Option<&str> = Some("a number");
         pub const parse_passes: Option<&str> =
             Some("a space-separated list of passes, or `all`");
@@ -948,6 +949,14 @@ macro_rules! options {
             }
         }
 
+        fn parse_threads(slot: &mut usize, v: Option<&str>) -> bool {
+            match v.and_then(|s| s.parse().ok()) {
+                Some(0) => { *slot = ::num_cpus::get(); true },
+                Some(i) => { *slot = i; true },
+                None => false
+            }
+        }
+
         fn parse_uint(slot: &mut usize, v: Option<&str>) -> bool {
             match v.and_then(|s| s.parse().ok()) {
                 Some(i) => { *slot = i; true },
@@ -1251,7 +1260,11 @@ options! {DebuggingOptions, DebuggingSetter, basic_debugging_options,
         "prints the LLVM optimization passes being run"),
     ast_json: bool = (false, parse_bool, [UNTRACKED],
         "print the AST as JSON and halt"),
-    threads: Option<usize> = (None, parse_opt_uint, [UNTRACKED],
+    // We default to 1 here since we want to behave like
+    // a sequential compiler for now. This'll likely be adjusted
+    // in the future. Note that -Zthreads=0 is the way to get
+    // the num_cpus behavior.
+    threads: usize = (1, parse_threads, [UNTRACKED],
         "use a thread pool with N threads"),
     ast_json_noexpand: bool = (false, parse_bool, [UNTRACKED],
         "print the pre-expansion AST as JSON and halt"),
@@ -2146,14 +2159,14 @@ pub fn build_session_options_and_crate_config(
         }
     }
 
-    if debugging_opts.threads == Some(0) {
+    if debugging_opts.threads == 0 {
         early_error(
             error_format,
             "value for threads must be a positive non-zero integer",
         );
     }
 
-    if debugging_opts.threads.unwrap_or(1) > 1 && debugging_opts.fuel.is_some() {
+    if debugging_opts.threads > 1 && debugging_opts.fuel.is_some() {
         early_error(
             error_format,
             "optimization fuel is incompatible with multiple threads",

src/librustc/session/mod.rs

@@ -32,7 +32,7 @@ use syntax::source_map;
 use syntax::parse::{self, ParseSess};
 use syntax::symbol::Symbol;
 use syntax_pos::{MultiSpan, Span};
-use crate::util::profiling::SelfProfiler;
+use crate::util::profiling::{SelfProfiler, SelfProfilerRef};
 
 use rustc_target::spec::{PanicStrategy, RelroLevel, Target, TargetTriple};
 use rustc_data_structures::flock;
@@ -129,7 +129,7 @@ pub struct Session {
     pub profile_channel: Lock<Option<mpsc::Sender<ProfileQueriesMsg>>>,
 
     /// Used by `-Z self-profile`.
-    pub self_profiling: Option<Arc<SelfProfiler>>,
+    pub prof: SelfProfilerRef,
 
     /// Some measurements that are being gathered during compilation.
     pub perf_stats: PerfStats,
@@ -835,24 +835,6 @@ impl Session {
         }
     }
 
-    #[inline(never)]
-    #[cold]
-    fn profiler_active<F: FnOnce(&SelfProfiler) -> ()>(&self, f: F) {
-        match &self.self_profiling {
-            None => bug!("profiler_active() called but there was no profiler active"),
-            Some(profiler) => {
-                f(&profiler);
-            }
-        }
-    }
-
-    #[inline(always)]
-    pub fn profiler<F: FnOnce(&SelfProfiler) -> ()>(&self, f: F) {
-        if unlikely!(self.self_profiling.is_some()) {
-            self.profiler_active(f)
-        }
-    }
-
     pub fn print_perf_stats(&self) {
         println!(
             "Total time spent computing symbol hashes:      {}",
@@ -896,16 +878,10 @@ impl Session {
         ret
     }
 
-    /// Returns the number of query threads that should be used for this
-    /// compilation
-    pub fn threads_from_count(query_threads: Option<usize>) -> usize {
-        query_threads.unwrap_or(::num_cpus::get())
-    }
-
     /// Returns the number of query threads that should be used for this
     /// compilation
     pub fn threads(&self) -> usize {
-        Self::threads_from_count(self.opts.debugging_opts.threads)
+        self.opts.debugging_opts.threads
     }
 
     /// Returns the number of codegen units that should be used for this
@@ -1257,7 +1233,7 @@ fn build_session_(
         imported_macro_spans: OneThread::new(RefCell::new(FxHashMap::default())),
         incr_comp_session: OneThread::new(RefCell::new(IncrCompSession::NotInitialized)),
         cgu_reuse_tracker,
-        self_profiling: self_profiler,
+        prof: SelfProfilerRef::new(self_profiler),
         profile_channel: Lock::new(None),
         perf_stats: PerfStats {
             symbol_hash_time: Lock::new(Duration::from_secs(0)),

src/librustc/ty/context.rs

@@ -45,6 +45,7 @@ use crate::ty::CanonicalPolyFnSig;
 use crate::util::common::ErrorReported;
 use crate::util::nodemap::{DefIdMap, DefIdSet, ItemLocalMap, ItemLocalSet};
 use crate::util::nodemap::{FxHashMap, FxHashSet};
+use crate::util::profiling::SelfProfilerRef;
 
 use errors::DiagnosticBuilder;
 use arena::SyncDroplessArena;
@@ -1030,6 +1031,8 @@ pub struct GlobalCtxt<'tcx> {
 
     pub dep_graph: DepGraph,
 
+    pub prof: SelfProfilerRef,
+
     /// Common objects.
     pub common: Common<'tcx>,
 
@@ -1260,6 +1263,7 @@ impl<'tcx> TyCtxt<'tcx> {
             arena: WorkerLocal::new(|_| Arena::default()),
             interners,
             dep_graph,
+            prof: s.prof.clone(),
             common,
             types: common_types,
             lifetimes: common_lifetimes,