Auto merge of #65565 - tmandry:rollup-s8n9bie, r=tmandry

Rollup of 17 pull requests

Successful merges:

 - #65016 (Always inline `mem::{size_of,align_of}` in debug builds)
 - #65197 (Prepare `MutVisitor`s to handle interned projections)
 - #65201 (Disable Go and OCaml bindings when building LLVM)
 - #65364 (Collect occurrences of empty blocks for mismatched braces diagnostic)
 - #65417 (Add more coherence tests)
 - #65434 (Add long error explanation for E0577)
 - #65455 (Avoid unnecessary `TokenTree` to `TokenStream` conversions)
 - #65472 (Use a sharded dep node to dep node index map)
 - #65480 (Speed up `LexicalResolve::expansion()`)
 - #65496 (properly document panics in div_euclid and rem_euclid)
 - #65508 (add option to ping llvm ice-breakers to triagebot)
 - #65511 (save-analysis: Nest tables when processing impl block definitions)
 - #65513 (reorder fmt docs for more clarity)
 - #65532 (doc: make BitSet intro more short)
 - #65540 (show up some extra info when t!() fails)
 - #65549 (Fix left/right shift typo in wrapping rotate docs)
 - #65552 (Clarify diagnostics when using `~` as a unary op)

Failed merges:

 - #65471 (Add long error explanation for E0578)

r? @ghost

Author: bors

Diff for: src/bootstrap/lib.rs

@@ -1126,7 +1126,7 @@ impl Build {
         }
 
         let mut paths = Vec::new();
-        let contents = t!(fs::read(stamp));
+        let contents = t!(fs::read(stamp), &stamp);
         // This is the method we use for extracting paths from the stamp file passed to us. See
         // run_cargo for more information (in compile.rs).
         for part in contents.split(|b| *b == 0) {

Diff for: src/bootstrap/native.rs

@@ -157,6 +157,7 @@ impl Step for Llvm {
            .define("WITH_POLLY", "OFF")
            .define("LLVM_ENABLE_TERMINFO", "OFF")
            .define("LLVM_ENABLE_LIBEDIT", "OFF")
+           .define("LLVM_ENABLE_BINDINGS", "OFF")
            .define("LLVM_ENABLE_Z3_SOLVER", "OFF")
            .define("LLVM_PARALLEL_COMPILE_JOBS", builder.jobs().to_string())
            .define("LLVM_TARGET_ARCH", target.split('-').next().unwrap())
@@ -169,15 +170,6 @@ impl Step for Llvm {
             }
         }
 
-        // By default, LLVM will automatically find OCaml and, if it finds it,
-        // install the LLVM bindings in LLVM_OCAML_INSTALL_PATH, which defaults
-        // to /usr/bin/ocaml.
-        // This causes problem for non-root builds of Rust. Side-step the issue
-        // by setting LLVM_OCAML_INSTALL_PATH to a relative path, so it installs
-        // in the prefix.
-        cfg.define("LLVM_OCAML_INSTALL_PATH",
-            env::var_os("LLVM_OCAML_INSTALL_PATH").unwrap_or_else(|| "usr/lib/ocaml".into()));
-
         let want_lldb = builder.config.lldb_enabled && !self.emscripten;
 
         // This setting makes the LLVM tools link to the dynamic LLVM library,

Diff for: src/build_helper/lib.rs

@@ -21,6 +21,13 @@ macro_rules! t {
             Err(e) => panic!("{} failed with {}", stringify!($e), e),
         }
     };
+    // it can show extra info in the second parameter
+    ($e:expr, $extra:expr) => {
+        match $e {
+            Ok(e) => e,
+            Err(e) => panic!("{} failed with {} ({:?})", stringify!($e), e, $extra),
+        }
+    };
 }
 
 // Because Cargo adds the compiler's dylib path to our library search path, llvm-config may

Diff for: src/liballoc/fmt.rs

@@ -86,27 +86,74 @@
 //! parameters (corresponding to `format_spec` in the syntax above). These
 //! parameters affect the string representation of what's being formatted.
 //!
+//! ## Width
+//!
+//! ```
+//! // All of these print "Hello x    !"
+//! println!("Hello {:5}!", "x");
+//! println!("Hello {:1$}!", "x", 5);
+//! println!("Hello {1:0$}!", 5, "x");
+//! println!("Hello {:width$}!", "x", width = 5);
+//! ```
+//!
+//! This is a parameter for the "minimum width" that the format should take up.
+//! If the value's string does not fill up this many characters, then the
+//! padding specified by fill/alignment will be used to take up the required
+//! space (see below).
+//!
+//! The value for the width can also be provided as a [`usize`] in the list of
+//! parameters by adding a postfix `$`, indicating that the second argument is
+//! a [`usize`] specifying the width.
+//!
+//! Referring to an argument with the dollar syntax does not affect the "next
+//! argument" counter, so it's usually a good idea to refer to arguments by
+//! position, or use named arguments.
+//!
 //! ## Fill/Alignment
 //!
-//! The fill character is provided normally in conjunction with the
-//! [`width`](#width)
-//! parameter. This indicates that if the value being formatted is smaller than
-//! `width` some extra characters will be printed around it. The extra
-//! characters are specified by `fill`, and the alignment can be one of the
-//! following options:
+//! ```
+//! assert_eq!(format!("Hello {:<5}!", "x"),  "Hello x    !");
+//! assert_eq!(format!("Hello {:-<5}!", "x"), "Hello x----!");
+//! assert_eq!(format!("Hello {:^5}!", "x"),  "Hello   x  !");
+//! assert_eq!(format!("Hello {:>5}!", "x"),  "Hello     x!");
+//! ```
 //!
-//! * `<` - the argument is left-aligned in `width` columns
-//! * `^` - the argument is center-aligned in `width` columns
-//! * `>` - the argument is right-aligned in `width` columns
+//! The optional fill character and alignment is provided normally in conjunction with the
+//! [`width`](#width) parameter. It must be defined before `width`, right after the `:`.
+//! This indicates that if the value being formatted is smaller than
+//! `width` some extra characters will be printed around it.
+//! Filling comes in the following variants for different alignments:
+//!
+//! * `[fill]<` - the argument is left-aligned in `width` columns
+//! * `[fill]^` - the argument is center-aligned in `width` columns
+//! * `[fill]>` - the argument is right-aligned in `width` columns
+//!
+//! The default [fill/alignment](#fillalignment) for non-numerics is a space and
+//! left-aligned. The
+//! defaults for numeric formatters is also a space but with right-alignment. If
+//! the `0` flag (see below) is specified for numerics, then the implicit fill character is
+//! `0`.
 //!
 //! Note that alignment may not be implemented by some types. In particular, it
 //! is not generally implemented for the `Debug` trait.  A good way to ensure
-//! padding is applied is to format your input, then use this resulting string
-//! to pad your output.
+//! padding is applied is to format your input, then pad this resulting string
+//! to obtain your output:
+//!
+//! ```
+//! println!("Hello {:^15}!", format!("{:?}", Some("hi"))); // => "Hello   Some("hi")   !"
+//! ```
 //!
 //! ## Sign/`#`/`0`
 //!
-//! These can all be interpreted as flags for a particular formatter.
+//! ```
+//! assert_eq!(format!("Hello {:+}!", 5), "Hello +5!");
+//! assert_eq!(format!("{:#x}!", 27), "0x1b!");
+//! assert_eq!(format!("Hello {:05}!", 5),  "Hello 00005!");
+//! assert_eq!(format!("Hello {:05}!", -5), "Hello -0005!");
+//! assert_eq!(format!("{:#010x}!", 27), "0x0000001b!");
+//! ```
+//!
+//! These are all flags altering the behavior of the formatter.
 //!
 //! * `+` - This is intended for numeric types and indicates that the sign
 //!         should always be printed. Positive signs are never printed by
@@ -121,44 +168,15 @@
 //!     * `#X` - precedes the argument with a `0x`
 //!     * `#b` - precedes the argument with a `0b`
 //!     * `#o` - precedes the argument with a `0o`
-//! * `0` - This is used to indicate for integer formats that the padding should
+//! * `0` - This is used to indicate for integer formats that the padding to `width` should
 //!         both be done with a `0` character as well as be sign-aware. A format
 //!         like `{:08}` would yield `00000001` for the integer `1`, while the
 //!         same format would yield `-0000001` for the integer `-1`. Notice that
 //!         the negative version has one fewer zero than the positive version.
 //!         Note that padding zeroes are always placed after the sign (if any)
 //!         and before the digits. When used together with the `#` flag, a similar
 //!         rule applies: padding zeroes are inserted after the prefix but before
-//!         the digits.
-//!
-//! ## Width
-//!
-//! This is a parameter for the "minimum width" that the format should take up.
-//! If the value's string does not fill up this many characters, then the
-//! padding specified by fill/alignment will be used to take up the required
-//! space.
-//!
-//! The default [fill/alignment](#fillalignment) for non-numerics is a space and
-//! left-aligned. The
-//! defaults for numeric formatters is also a space but with right-alignment. If
-//! the `0` flag is specified for numerics, then the implicit fill character is
-//! `0`.
-//!
-//! The value for the width can also be provided as a [`usize`] in the list of
-//! parameters by using the dollar syntax indicating that the second argument is
-//! a [`usize`] specifying the width, for example:
-//!
-//! ```
-//! // All of these print "Hello x    !"
-//! println!("Hello {:5}!", "x");
-//! println!("Hello {:1$}!", "x", 5);
-//! println!("Hello {1:0$}!", 5, "x");
-//! println!("Hello {:width$}!", "x", width = 5);
-//! ```
-//!
-//! Referring to an argument with the dollar syntax does not affect the "next
-//! argument" counter, so it's usually a good idea to refer to arguments by
-//! position, or use named arguments.
+//!         the digits. The prefix is included in the total width.
 //!
 //! ## Precision
 //!
@@ -235,9 +253,14 @@
 //! them with the same character. For example, the `{` character is escaped with
 //! `{{` and the `}` character is escaped with `}}`.
 //!
+//! ```
+//! assert_eq!(format!("Hello {{}}"), "Hello {}");
+//! assert_eq!(format!("{{ Hello"), "{ Hello");
+//! ```
+//!
 //! # Syntax
 //!
-//! To summarize, you can find the full grammar of format strings.
+//! To summarize, here you can find the full grammar of format strings.
 //! The syntax for the formatting language used is drawn from other languages,
 //! so it should not be too alien. Arguments are formatted with Python-like
 //! syntax, meaning that arguments are surrounded by `{}` instead of the C-like

Diff for: src/libcore/mem/mod.rs

@@ -236,7 +236,7 @@ pub fn forget_unsized<T: ?Sized>(t: T) {
 /// ```
 ///
 /// [alignment]: ./fn.align_of.html
-#[inline]
+#[inline(always)]
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_promotable]
 pub const fn size_of<T>() -> usize {
@@ -328,7 +328,7 @@ pub fn min_align_of_val<T: ?Sized>(val: &T) -> usize {
 ///
 /// assert_eq!(4, mem::align_of::<i32>());
 /// ```
-#[inline]
+#[inline(always)]
 #[stable(feature = "rust1", since = "1.0.0")]
 #[rustc_promotable]
 pub const fn align_of<T>() -> usize {

Diff for: src/libcore/num/mod.rs

@@ -1864,7 +1864,7 @@ if `self < 0`, this is equal to round towards +/- infinity.
 
 # Panics
 
-This function will panic if `rhs` is 0.
+This function will panic if `rhs` is 0 or the division results in overflow.
 
 # Examples
 
@@ -1903,7 +1903,7 @@ This is done as if by the Euclidean division algorithm -- given
 
 # Panics
 
-This function will panic if `rhs` is 0.
+This function will panic if `rhs` is 0 or the division results in overflow.
 
 # Examples
 
@@ -3694,6 +3694,10 @@ Since, for the positive integers, all common
 definitions of division are equal, this
 is exactly equal to `self / rhs`.
 
+# Panics
+
+This function will panic if `rhs` is 0.
+
 # Examples
 
 Basic usage:
@@ -3719,6 +3723,10 @@ Since, for the positive integers, all common
 definitions of division are equal, this
 is exactly equal to `self % rhs`.
 
+# Panics
+
+This function will panic if `rhs` is 0.
+
 # Examples
 
 Basic usage:

Diff for: src/libcore/num/wrapping.rs

@@ -437,7 +437,7 @@ assert_eq!(n.trailing_zeros(), 3);
             /// wrapping the truncated bits to the end of the resulting
             /// integer.
             ///
-            /// Please note this isn't the same operation as the `>>` shifting
+            /// Please note this isn't the same operation as the `<<` shifting
             /// operator!
             ///
             /// # Examples
@@ -463,7 +463,7 @@ assert_eq!(n.trailing_zeros(), 3);
             /// wrapping the truncated bits to the beginning of the resulting
             /// integer.
             ///
-            /// Please note this isn't the same operation as the `<<` shifting
+            /// Please note this isn't the same operation as the `>>` shifting
             /// operator!
             ///
             /// # Examples

Diff for: src/librustc/dep_graph/graph.rs

@@ -4,6 +4,7 @@ use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_index::vec::{Idx, IndexVec};
 use smallvec::SmallVec;
 use rustc_data_structures::sync::{Lrc, Lock, AtomicU32, AtomicU64, Ordering};
+use rustc_data_structures::sharded::{self, Sharded};
 use std::sync::atomic::Ordering::SeqCst;
 use std::env;
 use std::hash::Hash;
@@ -381,7 +382,7 @@ impl DepGraph {
     #[inline]
     pub fn read(&self, v: DepNode) {
         if let Some(ref data) = self.data {
-            let map = data.current.node_to_node_index.lock();
+            let map = data.current.node_to_node_index.get_shard_by_value(&v).lock();
             if let Some(dep_node_index) = map.get(&v).copied() {
                 std::mem::drop(map);
                 data.read_index(dep_node_index);
@@ -405,6 +406,7 @@ impl DepGraph {
             .unwrap()
             .current
             .node_to_node_index
+            .get_shard_by_value(dep_node)
             .lock()
             .get(dep_node)
             .cloned()
@@ -414,7 +416,11 @@ impl DepGraph {
     #[inline]
     pub fn dep_node_exists(&self, dep_node: &DepNode) -> bool {
         if let Some(ref data) = self.data {
-            data.current.node_to_node_index.lock().contains_key(dep_node)
+            data.current
+                .node_to_node_index
+                .get_shard_by_value(&dep_node)
+                .lock()
+                .contains_key(dep_node)
         } else {
             false
         }
@@ -595,7 +601,11 @@ impl DepGraph {
 
         #[cfg(not(parallel_compiler))]
         {
-            debug_assert!(!data.current.node_to_node_index.lock().contains_key(dep_node));
+            debug_assert!(!data.current
+                               .node_to_node_index
+                               .get_shard_by_value(dep_node)
+                               .lock()
+                               .contains_key(dep_node));
             debug_assert!(data.colors.get(prev_dep_node_index).is_none());
         }
 
@@ -927,7 +937,7 @@ struct DepNodeData {
 /// acquire the lock on `data.`
 pub(super) struct CurrentDepGraph {
     data: Lock<IndexVec<DepNodeIndex, DepNodeData>>,
-    node_to_node_index: Lock<FxHashMap<DepNode, DepNodeIndex>>,
+    node_to_node_index: Sharded<FxHashMap<DepNode, DepNodeIndex>>,
 
     /// Used to trap when a specific edge is added to the graph.
     /// This is used for debug purposes and is only active with `debug_assertions`.
@@ -985,8 +995,8 @@ impl CurrentDepGraph {
 
         CurrentDepGraph {
             data: Lock::new(IndexVec::with_capacity(new_node_count_estimate)),
-            node_to_node_index: Lock::new(FxHashMap::with_capacity_and_hasher(
-                new_node_count_estimate,
+            node_to_node_index: Sharded::new(|| FxHashMap::with_capacity_and_hasher(
+                new_node_count_estimate / sharded::SHARDS,
                 Default::default(),
             )),
             anon_id_seed: stable_hasher.finish(),
@@ -1035,7 +1045,10 @@ impl CurrentDepGraph {
         edges: SmallVec<[DepNodeIndex; 8]>,
         fingerprint: Fingerprint
     ) -> DepNodeIndex {
-        debug_assert!(!self.node_to_node_index.lock().contains_key(&dep_node));
+        debug_assert!(!self.node_to_node_index
+                           .get_shard_by_value(&dep_node)
+                           .lock()
+                           .contains_key(&dep_node));
         self.intern_node(dep_node, edges, fingerprint)
     }
 
@@ -1045,7 +1058,7 @@ impl CurrentDepGraph {
         edges: SmallVec<[DepNodeIndex; 8]>,
         fingerprint: Fingerprint
     ) -> DepNodeIndex {
-        match self.node_to_node_index.lock().entry(dep_node) {
+        match self.node_to_node_index.get_shard_by_value(&dep_node).lock().entry(dep_node) {
             Entry::Occupied(entry) => *entry.get(),
             Entry::Vacant(entry) => {
                 let mut data = self.data.lock();