Auto merge of #54575 - pietroalbini:rollup, r=pietroalbini

Rollup of 12 pull requests

Successful merges:

 - #53518 (Add doc for impl From in char_convert)
 - #54058 (Introduce the partition_dedup/by/by_key methods for slices)
 - #54281 (Search box)
 - #54368 (Reduce code block sides padding)
 - #54498 (The project moved under the Mozilla umbrella)
 - #54518 (resolve: Do not block derive helper resolutions on single import resolutions)
 - #54522 (Fixed three small typos.)
 - #54529 (aarch64-pc-windows-msvc: Don't link libpanic_unwind to libtest.)
 - #54537 (Rename slice::exact_chunks() to slice::chunks_exact())
 - #54539 (Fix js error)
 - #54557 (incr.comp.: Don't automatically enable -Zshare-generics for incr. comp. builds.)
 - #54558 (Improvements to finding LLVM's FileCheck)

Failed merges:

r? @ghost

config.toml.example

@@ -322,6 +322,7 @@
 
 # Flag indicating whether codegen tests will be run or not. If you get an error
 # saying that the FileCheck executable is missing, you may want to disable this.
+# Also see the target's llvm-filecheck option.
 #codegen-tests = true
 
 # Flag indicating whether git info will be retrieved from .git automatically.
@@ -416,6 +417,10 @@
 # target.
 #llvm-config = "../path/to/llvm/root/bin/llvm-config"
 
+# Normally the build system can find LLVM's FileCheck utility, but if
+# not, you can specify an explicit file name for it.
+#llvm-filecheck = "/path/to/FileCheck"
+
 # Path to the custom jemalloc static library to link into the standard library
 # by default. This is only used if jemalloc is still enabled above
 #jemalloc = "/path/to/jemalloc/libjemalloc_pic.a"

src/bootstrap/config.rs

@@ -162,6 +162,8 @@ pub struct Config {
 pub struct Target {
     /// Some(path to llvm-config) if using an external LLVM.
     pub llvm_config: Option<PathBuf>,
+    /// Some(path to FileCheck) if one was specified.
+    pub llvm_filecheck: Option<PathBuf>,
     pub jemalloc: Option<PathBuf>,
     pub cc: Option<PathBuf>,
     pub cxx: Option<PathBuf>,
@@ -330,6 +332,7 @@ struct Rust {
 #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 struct TomlTarget {
     llvm_config: Option<String>,
+    llvm_filecheck: Option<String>,
     jemalloc: Option<String>,
     cc: Option<String>,
     cxx: Option<String>,
@@ -583,6 +586,9 @@ impl Config {
                 if let Some(ref s) = cfg.llvm_config {
                     target.llvm_config = Some(config.src.join(s));
                 }
+                if let Some(ref s) = cfg.llvm_filecheck {
+                    target.llvm_filecheck = Some(config.src.join(s));
+                }
                 if let Some(ref s) = cfg.jemalloc {
                     target.jemalloc = Some(config.src.join(s));
                 }

src/bootstrap/configure.py

@@ -95,6 +95,8 @@ def v(*args):
 v("bindir", "install.bindir", "install binaries")
 
 v("llvm-root", None, "set LLVM root")
+v("llvm-config", None, "set path to llvm-config")
+v("llvm-filecheck", None, "set path to LLVM's FileCheck utility")
 v("python", "build.python", "set path to python")
 v("jemalloc-root", None, "set directory where libjemalloc_pic.a is located")
 v("android-cross-path", "target.arm-linux-androideabi.android-ndk",
@@ -323,6 +325,10 @@ def set(key, value):
         set('build.cargo', value + '/bin/cargo')
     elif option.name == 'llvm-root':
         set('target.{}.llvm-config'.format(build()), value + '/bin/llvm-config')
+    elif option.name == 'llvm-config':
+        set('target.{}.llvm-config'.format(build()), value)
+    elif option.name == 'llvm-filecheck':
+        set('target.{}.llvm-filecheck'.format(build()), value)
     elif option.name == 'jemalloc-root':
         set('target.{}.jemalloc'.format(build()), value + '/libjemalloc_pic.a')
     elif option.name == 'tools':

src/bootstrap/lib.rs

@@ -641,9 +641,28 @@ impl Build {
     /// Returns the path to `FileCheck` binary for the specified target
     fn llvm_filecheck(&self, target: Interned<String>) -> PathBuf {
         let target_config = self.config.target_config.get(&target);
-        if let Some(s) = target_config.and_then(|c| c.llvm_config.as_ref()) {
+        if let Some(s) = target_config.and_then(|c| c.llvm_filecheck.as_ref()) {
+            s.to_path_buf()
+        } else if let Some(s) = target_config.and_then(|c| c.llvm_config.as_ref()) {
             let llvm_bindir = output(Command::new(s).arg("--bindir"));
-            Path::new(llvm_bindir.trim()).join(exe("FileCheck", &*target))
+            let filecheck = Path::new(llvm_bindir.trim()).join(exe("FileCheck", &*target));
+            if filecheck.exists() {
+                filecheck
+            } else {
+                // On Fedora the system LLVM installs FileCheck in the
+                // llvm subdirectory of the libdir.
+                let llvm_libdir = output(Command::new(s).arg("--libdir"));
+                let lib_filecheck = Path::new(llvm_libdir.trim())
+                    .join("llvm").join(exe("FileCheck", &*target));
+                if lib_filecheck.exists() {
+                    lib_filecheck
+                } else {
+                    // Return the most normal file name, even though
+                    // it doesn't exist, so that any error message
+                    // refers to that.
+                    filecheck
+                }
+            }
         } else {
             let base = self.llvm_out(self.config.build).join("build");
             let base = if !self.config.ninja && self.config.build.contains("msvc") {

src/doc/index.md

@@ -4,6 +4,23 @@
 nav {
     display: none;
 }
+#search-input {
+    width: calc(100% - 58px);
+}
+#search-but {
+    cursor: pointer;
+}
+#search-but, #search-input {
+    padding: 4px;
+    border: 1px solid #ccc;
+    border-radius: 3px;
+    outline: none;
+    font-size: 0.7em;
+    background-color: #fff;
+}
+#search-but:hover, #search-input:focus {
+    border-color: #55a9ff;
+}
 </style>
 
 Welcome to an overview of the documentation provided by the Rust project.
@@ -45,8 +62,9 @@ accomplishing various tasks.
 
 <div>
   <form action="std/index.html" method="get">
-    <input type="search" name="search"/>
-    <button>Search</button>
+    <input id="search-input" type="search" name="search"
+           placeholder="Search through the standard library"/>
+    <button id="search-but">Search</button>
   </form>
 </div>
 

src/doc/unstable-book/src/compiler-flags/profile.md

@@ -18,4 +18,4 @@ cargo run
 ```
 
 Once you've built and run your program, files with the `gcno` (after build) and `gcda` (after execution) extensions will be created.
-You can parse them with [llvm-cov gcov](http://llvm.org/docs/CommandGuide/llvm-cov.html#llvm-cov-gcov) or [grcov](https://github.com/marco-c/grcov).
+You can parse them with [llvm-cov gcov](https://llvm.org/docs/CommandGuide/llvm-cov.html#llvm-cov-gcov) or [grcov](https://github.com/mozilla/grcov).

src/liballoc/lib.rs

@@ -116,9 +116,10 @@
 #![feature(unsize)]
 #![feature(allocator_internals)]
 #![feature(on_unimplemented)]
-#![feature(exact_chunks)]
+#![feature(chunks_exact)]
 #![feature(rustc_const_unstable)]
 #![feature(const_vec_new)]
+#![feature(slice_partition_dedup)]
 #![feature(maybe_uninit)]
 
 // Allow testing this library

src/liballoc/slice.rs

@@ -123,8 +123,8 @@ pub use core::slice::{from_raw_parts, from_raw_parts_mut};
 pub use core::slice::{from_ref, from_mut};
 #[stable(feature = "slice_get_slice", since = "1.28.0")]
 pub use core::slice::SliceIndex;
-#[unstable(feature = "exact_chunks", issue = "47115")]
-pub use core::slice::{ExactChunks, ExactChunksMut};
+#[unstable(feature = "chunks_exact", issue = "47115")]
+pub use core::slice::{ChunksExact, ChunksExactMut};
 
 ////////////////////////////////////////////////////////////////////////////////
 // Basic slice extension methods

src/liballoc/tests/lib.rs

@@ -20,7 +20,7 @@
 #![feature(str_escape)]
 #![feature(try_reserve)]
 #![feature(unboxed_closures)]
-#![feature(exact_chunks)]
+#![feature(chunks_exact)]
 #![feature(repeat_generic_slice)]
 
 extern crate alloc_system;

src/liballoc/tests/slice.rs

@@ -975,27 +975,27 @@ fn test_chunksator_0() {
 }
 
 #[test]
-fn test_exact_chunksator() {
+fn test_chunks_exactator() {
     let v = &[1, 2, 3, 4, 5];
 
-    assert_eq!(v.exact_chunks(2).len(), 2);
+    assert_eq!(v.chunks_exact(2).len(), 2);
 
     let chunks: &[&[_]] = &[&[1, 2], &[3, 4]];
-    assert_eq!(v.exact_chunks(2).collect::<Vec<_>>(), chunks);
+    assert_eq!(v.chunks_exact(2).collect::<Vec<_>>(), chunks);
     let chunks: &[&[_]] = &[&[1, 2, 3]];
-    assert_eq!(v.exact_chunks(3).collect::<Vec<_>>(), chunks);
+    assert_eq!(v.chunks_exact(3).collect::<Vec<_>>(), chunks);
     let chunks: &[&[_]] = &[];
-    assert_eq!(v.exact_chunks(6).collect::<Vec<_>>(), chunks);
+    assert_eq!(v.chunks_exact(6).collect::<Vec<_>>(), chunks);
 
     let chunks: &[&[_]] = &[&[3, 4], &[1, 2]];
-    assert_eq!(v.exact_chunks(2).rev().collect::<Vec<_>>(), chunks);
+    assert_eq!(v.chunks_exact(2).rev().collect::<Vec<_>>(), chunks);
 }
 
 #[test]
 #[should_panic]
-fn test_exact_chunksator_0() {
+fn test_chunks_exactator_0() {
     let v = &[1, 2, 3, 4];
-    let _it = v.exact_chunks(0);
+    let _it = v.chunks_exact(0);
 }
 
 #[test]
@@ -1235,10 +1235,10 @@ fn test_mut_chunks_0() {
 }
 
 #[test]
-fn test_mut_exact_chunks() {
+fn test_mut_chunks_exact() {
     let mut v = [0, 1, 2, 3, 4, 5, 6];
-    assert_eq!(v.exact_chunks_mut(2).len(), 3);
-    for (i, chunk) in v.exact_chunks_mut(3).enumerate() {
+    assert_eq!(v.chunks_exact_mut(2).len(), 3);
+    for (i, chunk) in v.chunks_exact_mut(3).enumerate() {
         for x in chunk {
             *x = i as u8;
         }
@@ -1248,9 +1248,9 @@ fn test_mut_exact_chunks() {
 }
 
 #[test]
-fn test_mut_exact_chunks_rev() {
+fn test_mut_chunks_exact_rev() {
     let mut v = [0, 1, 2, 3, 4, 5, 6];
-    for (i, chunk) in v.exact_chunks_mut(3).rev().enumerate() {
+    for (i, chunk) in v.chunks_exact_mut(3).rev().enumerate() {
         for x in chunk {
             *x = i as u8;
         }
@@ -1261,9 +1261,9 @@ fn test_mut_exact_chunks_rev() {
 
 #[test]
 #[should_panic]
-fn test_mut_exact_chunks_0() {
+fn test_mut_chunks_exact_0() {
     let mut v = [1, 2, 3, 4];
-    let _it = v.exact_chunks_mut(0);
+    let _it = v.chunks_exact_mut(0);
 }
 
 #[test]

src/liballoc/vec.rs

@@ -947,10 +947,9 @@ impl<T> Vec<T> {
     /// Removes all but the first of consecutive elements in the vector satisfying a given equality
     /// relation.
     ///
-    /// The `same_bucket` function is passed references to two elements from the vector, and
-    /// returns `true` if the elements compare equal, or `false` if they do not. The elements are
-    /// passed in opposite order from their order in the vector, so if `same_bucket(a, b)` returns
-    /// `true`, `a` is removed.
+    /// The `same_bucket` function is passed references to two elements from the vector and
+    /// must determine if the elements compare equal. The elements are passed in opposite order
+    /// from their order in the slice, so if `same_bucket(a, b)` returns `true`, `a` is removed.
     ///
     /// If the vector is sorted, this removes all duplicates.
     ///
@@ -964,90 +963,12 @@ impl<T> Vec<T> {
     /// assert_eq!(vec, ["foo", "bar", "baz", "bar"]);
     /// ```
     #[stable(feature = "dedup_by", since = "1.16.0")]
-    pub fn dedup_by<F>(&mut self, mut same_bucket: F) where F: FnMut(&mut T, &mut T) -> bool {
-        unsafe {
-            // Although we have a mutable reference to `self`, we cannot make
-            // *arbitrary* changes. The `same_bucket` calls could panic, so we
-            // must ensure that the vector is in a valid state at all time.
-            //
-            // The way that we handle this is by using swaps; we iterate
-            // over all the elements, swapping as we go so that at the end
-            // the elements we wish to keep are in the front, and those we
-            // wish to reject are at the back. We can then truncate the
-            // vector. This operation is still O(n).
-            //
-            // Example: We start in this state, where `r` represents "next
-            // read" and `w` represents "next_write`.
-            //
-            //           r
-            //     +---+---+---+---+---+---+
-            //     | 0 | 1 | 1 | 2 | 3 | 3 |
-            //     +---+---+---+---+---+---+
-            //           w
-            //
-            // Comparing self[r] against self[w-1], this is not a duplicate, so
-            // we swap self[r] and self[w] (no effect as r==w) and then increment both
-            // r and w, leaving us with:
-            //
-            //               r
-            //     +---+---+---+---+---+---+
-            //     | 0 | 1 | 1 | 2 | 3 | 3 |
-            //     +---+---+---+---+---+---+
-            //               w
-            //
-            // Comparing self[r] against self[w-1], this value is a duplicate,
-            // so we increment `r` but leave everything else unchanged:
-            //
-            //                   r
-            //     +---+---+---+---+---+---+
-            //     | 0 | 1 | 1 | 2 | 3 | 3 |
-            //     +---+---+---+---+---+---+
-            //               w
-            //
-            // Comparing self[r] against self[w-1], this is not a duplicate,
-            // so swap self[r] and self[w] and advance r and w:
-            //
-            //                       r
-            //     +---+---+---+---+---+---+
-            //     | 0 | 1 | 2 | 1 | 3 | 3 |
-            //     +---+---+---+---+---+---+
-            //                   w
-            //
-            // Not a duplicate, repeat:
-            //
-            //                           r
-            //     +---+---+---+---+---+---+
-            //     | 0 | 1 | 2 | 3 | 1 | 3 |
-            //     +---+---+---+---+---+---+
-            //                       w
-            //
-            // Duplicate, advance r. End of vec. Truncate to w.
-
-            let ln = self.len();
-            if ln <= 1 {
-                return;
-            }
-
-            // Avoid bounds checks by using raw pointers.
-            let p = self.as_mut_ptr();
-            let mut r: usize = 1;
-            let mut w: usize = 1;
-
-            while r < ln {
-                let p_r = p.add(r);
-                let p_wm1 = p.add(w - 1);
-                if !same_bucket(&mut *p_r, &mut *p_wm1) {
-                    if r != w {
-                        let p_w = p_wm1.offset(1);
-                        mem::swap(&mut *p_r, &mut *p_w);
-                    }
-                    w += 1;
-                }
-                r += 1;
-            }
-
-            self.truncate(w);
-        }
+    pub fn dedup_by<F>(&mut self, same_bucket: F) where F: FnMut(&mut T, &mut T) -> bool {
+        let len = {
+            let (dedup, _) = self.as_mut_slice().partition_dedup_by(same_bucket);
+            dedup.len()
+        };
+        self.truncate(len);
     }
 
     /// Appends an element to the back of a collection.
@@ -1533,7 +1454,8 @@ impl<'a> Drop for SetLenOnDrop<'a> {
 }
 
 impl<T: PartialEq> Vec<T> {
-    /// Removes consecutive repeated elements in the vector.
+    /// Removes consecutive repeated elements in the vector according to the
+    /// [`PartialEq`] trait implementation.
     ///
     /// If the vector is sorted, this removes all duplicates.
     ///