Auto merge of #103225 - matthiaskrgr:rollup-1zkv87y, r=matthiaskrgr

Rollup of 4 pull requests

Successful merges:

 - #103166 (Optimize `slice_iter.copied().next_chunk()`)
 - #103176 (Fix `TyKind::is_simple_path`)
 - #103178 (Partially fix `src/test/run-make/coverage-reports` when cross-compiling)
 - #103198 (Update cargo)

Failed merges:

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

compiler/rustc_ast/src/ast.rs

@@ -2060,8 +2060,11 @@ pub fn is_unit(&self) -> bool {
     }
 
     pub fn is_simple_path(&self) -> Option<Symbol> {
-        if let TyKind::Path(None, Path { segments, .. }) = &self && segments.len() == 1 {
-            Some(segments[0].ident.name)
+        if let TyKind::Path(None, Path { segments, .. }) = &self
+            && let [segment] = &segments[..]
+            && segment.args.is_none()
+        {
+            Some(segment.ident.name)
         } else {
             None
         }

library/core/benches/iter.rs

@@ -1,4 +1,6 @@
 use core::iter::*;
+use core::mem;
+use core::num::Wrapping;
 use test::{black_box, Bencher};
 
 #[bench]
@@ -398,3 +400,21 @@ fn bench_trusted_random_access_adapters(b: &mut Bencher) {
         acc
     })
 }
+
+/// Exercises the iter::Copied specialization for slice::Iter
+#[bench]
+fn bench_copied_array_chunks(b: &mut Bencher) {
+    let v = vec![1u8; 1024];
+
+    b.iter(|| {
+        black_box(&v)
+            .iter()
+            .copied()
+            .array_chunks::<{ mem::size_of::<u64>() }>()
+            .map(|ary| {
+                let d = u64::from_ne_bytes(ary);
+                Wrapping(d.rotate_left(7).wrapping_add(1))
+            })
+            .sum::<Wrapping<u64>>()
+    })
+}

library/core/benches/lib.rs

@@ -4,6 +4,7 @@
 #![feature(int_log)]
 #![feature(test)]
 #![feature(trusted_random_access)]
+#![feature(iter_array_chunks)]
 
 extern crate test;
 

library/core/src/iter/adapters/copied.rs

@@ -2,7 +2,10 @@
     zip::try_get_unchecked, TrustedRandomAccess, TrustedRandomAccessNoCoerce,
 };
 use crate::iter::{FusedIterator, TrustedLen};
+use crate::mem::MaybeUninit;
+use crate::mem::SizedTypeProperties;
 use crate::ops::Try;
+use crate::{array, ptr};
 
 /// An iterator that copies the elements of an underlying iterator.
 ///
@@ -44,6 +47,15 @@ fn next(&mut self) -> Option<T> {
         self.it.next().copied()
     }
 
+    fn next_chunk<const N: usize>(
+        &mut self,
+    ) -> Result<[Self::Item; N], array::IntoIter<Self::Item, N>>
+    where
+        Self: Sized,
+    {
+        <I as SpecNextChunk<'_, N, T>>::spec_next_chunk(&mut self.it)
+    }
+
     fn size_hint(&self) -> (usize, Option<usize>) {
         self.it.size_hint()
     }
@@ -166,3 +178,65 @@ unsafe impl<'a, I, T: 'a> TrustedLen for Copied<I>
     T: Copy,
 {
 }
+
+trait SpecNextChunk<'a, const N: usize, T: 'a>: Iterator<Item = &'a T>
+where
+    T: Copy,
+{
+    fn spec_next_chunk(&mut self) -> Result<[T; N], array::IntoIter<T, N>>;
+}
+
+impl<'a, const N: usize, I, T: 'a> SpecNextChunk<'a, N, T> for I
+where
+    I: Iterator<Item = &'a T>,
+    T: Copy,
+{
+    default fn spec_next_chunk(&mut self) -> Result<[T; N], array::IntoIter<T, N>> {
+        array::iter_next_chunk(&mut self.map(|e| *e))
+    }
+}
+
+impl<'a, const N: usize, T: 'a> SpecNextChunk<'a, N, T> for crate::slice::Iter<'a, T>
+where
+    T: Copy,
+{
+    fn spec_next_chunk(&mut self) -> Result<[T; N], array::IntoIter<T, N>> {
+        let mut raw_array = MaybeUninit::uninit_array();
+
+        let len = self.len();
+
+        if T::IS_ZST {
+            if len < N {
+                let _ = self.advance_by(len);
+                // SAFETY: ZSTs can be conjured ex nihilo; only the amount has to be correct
+                return Err(unsafe { array::IntoIter::new_unchecked(raw_array, 0..len) });
+            }
+
+            let _ = self.advance_by(N);
+            // SAFETY: ditto
+            return Ok(unsafe { MaybeUninit::array_assume_init(raw_array) });
+        }
+
+        if len < N {
+            // SAFETY: `len` indicates that this many elements are available and we just checked that
+            // it fits into the array.
+            unsafe {
+                ptr::copy_nonoverlapping(
+                    self.as_ref().as_ptr(),
+                    raw_array.as_mut_ptr() as *mut T,
+                    len,
+                );
+                let _ = self.advance_by(len);
+                return Err(array::IntoIter::new_unchecked(raw_array, 0..len));
+            }
+        }
+
+        // SAFETY: `len` is larger than the array size. Copy a fixed amount here to fully initialize
+        // the array.
+        unsafe {
+            ptr::copy_nonoverlapping(self.as_ref().as_ptr(), raw_array.as_mut_ptr() as *mut T, N);
+            let _ = self.advance_by(N);
+            Ok(MaybeUninit::array_assume_init(raw_array))
+        }
+    }
+}

src/test/run-make/coverage-reports/Makefile

@@ -1,6 +1,11 @@
 # needs-profiler-support
 # ignore-windows-gnu
 
+# FIXME(pietroalbini): this test currently does not work on cross-compiled
+# targets because remote-test is not capable of sending back the *.profraw
+# files generated by the LLVM instrumentation.
+# ignore-cross-compile
+
 # Rust coverage maps support LLVM Coverage Mapping Format versions 5 and 6,
 # corresponding with LLVM versions 12 and 13, respectively.
 # When upgrading LLVM versions, consider whether to enforce a minimum LLVM
@@ -81,13 +86,13 @@ include clear_expected_if_blessed
 	# Compile the test library with coverage instrumentation
 	$(RUSTC) $(SOURCEDIR)/lib/$@.rs \
 			$$( sed -n 's/^\/\/ compile-flags: \([^#]*\).*/\1/p' $(SOURCEDIR)/lib/$@.rs ) \
-			--crate-type rlib -Cinstrument-coverage
+			--crate-type rlib -Cinstrument-coverage --target $(TARGET)
 
 %: $(SOURCEDIR)/%.rs
 	# Compile the test program with coverage instrumentation
 	$(RUSTC) $(SOURCEDIR)/$@.rs \
 			$$( sed -n 's/^\/\/ compile-flags: \([^#]*\).*/\1/p' $(SOURCEDIR)/$@.rs ) \
-			-L "$(TMPDIR)" -Cinstrument-coverage
+			-L "$(TMPDIR)" -Cinstrument-coverage --target $(TARGET)
 
 	# Run it in order to generate some profiling data,
 	# with `LLVM_PROFILE_FILE=<profdata_file>` environment variable set to

src/test/ui/deriving/deriving-all-codegen.rs

@@ -85,7 +85,7 @@ enum Mixed {
     P,
     Q,
     R(u32),
-    S { d1: u32, d2: u32 },
+    S { d1: Option<u32>, d2: Option<i32> },
 }
 
 // An enum with no fieldless variants. Note that `Default` cannot be derived

src/test/ui/deriving/deriving-all-codegen.stdout

@@ -809,8 +809,8 @@ enum Mixed {
     Q,
     R(u32),
     S {
-        d1: u32,
-        d2: u32,
+        d1: Option<u32>,
+        d2: Option<i32>,
     },
 }
 #[automatically_derived]
@@ -818,6 +818,8 @@ impl ::core::clone::Clone for Mixed {
     #[inline]
     fn clone(&self) -> Mixed {
         let _: ::core::clone::AssertParamIsClone<u32>;
+        let _: ::core::clone::AssertParamIsClone<Option<u32>>;
+        let _: ::core::clone::AssertParamIsClone<Option<i32>>;
         *self
     }
 }
@@ -886,6 +888,8 @@ impl ::core::cmp::Eq for Mixed {
     #[no_coverage]
     fn assert_receiver_is_total_eq(&self) -> () {
         let _: ::core::cmp::AssertParamIsEq<u32>;
+        let _: ::core::cmp::AssertParamIsEq<Option<u32>>;
+        let _: ::core::cmp::AssertParamIsEq<Option<i32>>;
     }
 }
 #[automatically_derived]

src/test/ui/deriving/issue-103157.rs

@@ -0,0 +1,12 @@
+// check-fail
+
+#[derive(PartialEq, Eq)]
+pub enum Value {
+    Boolean(Option<bool>),
+    Float(Option<f64>), //~ ERROR the trait bound `f64: Eq` is not satisfied
+}
+
+fn main() {
+    let a = Value::Float(Some(f64::NAN));
+    assert!(a == a);
+}

src/test/ui/deriving/issue-103157.stderr

@@ -0,0 +1,30 @@
+error[E0277]: the trait bound `f64: Eq` is not satisfied
+  --> $DIR/issue-103157.rs:6:11
+   |
+LL | #[derive(PartialEq, Eq)]
+   |                     -- in this derive macro expansion
+...
+LL |     Float(Option<f64>),
+   |           ^^^^^^^^^^^ the trait `Eq` is not implemented for `f64`
+   |
+   = help: the following other types implement trait `Eq`:
+             i128
+             i16
+             i32
+             i64
+             i8
+             isize
+             u128
+             u16
+           and 4 others
+   = note: required for `Option<f64>` to implement `Eq`
+note: required by a bound in `AssertParamIsEq`
+  --> $SRC_DIR/core/src/cmp.rs:LL:COL
+   |
+LL | pub struct AssertParamIsEq<T: Eq + ?Sized> {
+   |                               ^^ required by this bound in `AssertParamIsEq`
+   = note: this error originates in the derive macro `Eq` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.

src/tools/cargo

@@ -1 +1 @@
-Subproject commit b332991a57c9d055f1864de1eed93e2178d49440
+Subproject commit 3ff044334f0567ce1481c78603aeee7211b91623