Rollup merge of rust-lang#137483 - bend-n:😅, r=Noratrieb

rename sub_ptr to offset_from_unsigned

i also made `byte_sub_ptr` `byte_offset_from_unsigned`

fixes rust-lang#137121
tracking issue rust-lang#95892

Author: tgross35

alloc/src/vec/drain.rs

@@ -232,7 +232,7 @@ impl<T, A: Allocator> Drop for Drain<'_, T, A> {
             // it from the original vec but also avoid creating a &mut to the front since that could
             // invalidate raw pointers to it which some unsafe code might rely on.
             let vec_ptr = vec.as_mut().as_mut_ptr();
-            let drop_offset = drop_ptr.sub_ptr(vec_ptr);
+            let drop_offset = drop_ptr.offset_from_unsigned(vec_ptr);
             let to_drop = ptr::slice_from_raw_parts_mut(vec_ptr.add(drop_offset), drop_len);
             ptr::drop_in_place(to_drop);
         }

alloc/src/vec/in_place_collect.rs

@@ -379,7 +379,7 @@ where
         let sink =
             self.try_fold::<_, _, Result<_, !>>(sink, write_in_place_with_drop(end)).into_ok();
         // iteration succeeded, don't drop head
-        unsafe { ManuallyDrop::new(sink).dst.sub_ptr(dst_buf) }
+        unsafe { ManuallyDrop::new(sink).dst.offset_from_unsigned(dst_buf) }
     }
 }
 

alloc/src/vec/in_place_drop.rs

@@ -14,7 +14,7 @@ pub(super) struct InPlaceDrop<T> {
 
 impl<T> InPlaceDrop<T> {
     fn len(&self) -> usize {
-        unsafe { self.dst.sub_ptr(self.inner) }
+        unsafe { self.dst.offset_from_unsigned(self.inner) }
     }
 }
 

alloc/src/vec/into_iter.rs

@@ -179,7 +179,7 @@ impl<T, A: Allocator> IntoIter<T, A> {
                 // say that they're all at the beginning of the "allocation".
                 0..this.len()
             } else {
-                this.ptr.sub_ptr(this.buf)..this.end.sub_ptr(buf)
+                this.ptr.offset_from_unsigned(this.buf)..this.end.offset_from_unsigned(buf)
             };
             let cap = this.cap;
             let alloc = ManuallyDrop::take(&mut this.alloc);
@@ -230,7 +230,7 @@ impl<T, A: Allocator> Iterator for IntoIter<T, A> {
         let exact = if T::IS_ZST {
             self.end.addr().wrapping_sub(self.ptr.as_ptr().addr())
         } else {
-            unsafe { non_null!(self.end, T).sub_ptr(self.ptr) }
+            unsafe { non_null!(self.end, T).offset_from_unsigned(self.ptr) }
         };
         (exact, Some(exact))
     }

core/src/ptr/const_ptr.rs

@@ -724,7 +724,7 @@ impl<T: ?Sized> *const T {
     /// that their safety preconditions are met:
     /// ```rust
     /// # unsafe fn blah(ptr: *const i32, origin: *const i32, count: usize) -> bool { unsafe {
-    /// ptr.sub_ptr(origin) == count
+    /// ptr.offset_from_unsigned(origin) == count
     /// # &&
     /// origin.add(count) == ptr
     /// # &&
@@ -755,20 +755,20 @@ impl<T: ?Sized> *const T {
     /// let ptr1: *const i32 = &a[1];
     /// let ptr2: *const i32 = &a[3];
     /// unsafe {
-    ///     assert_eq!(ptr2.sub_ptr(ptr1), 2);
+    ///     assert_eq!(ptr2.offset_from_unsigned(ptr1), 2);
     ///     assert_eq!(ptr1.add(2), ptr2);
     ///     assert_eq!(ptr2.sub(2), ptr1);
-    ///     assert_eq!(ptr2.sub_ptr(ptr2), 0);
+    ///     assert_eq!(ptr2.offset_from_unsigned(ptr2), 0);
     /// }
     ///
     /// // This would be incorrect, as the pointers are not correctly ordered:
-    /// // ptr1.sub_ptr(ptr2)
+    /// // ptr1.offset_from_unsigned(ptr2)
     /// ```
     #[stable(feature = "ptr_sub_ptr", since = "CURRENT_RUSTC_VERSION")]
     #[rustc_const_stable(feature = "const_ptr_sub_ptr", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
-    pub const unsafe fn sub_ptr(self, origin: *const T) -> usize
+    pub const unsafe fn offset_from_unsigned(self, origin: *const T) -> usize
     where
         T: Sized,
     {
@@ -786,7 +786,7 @@ impl<T: ?Sized> *const T {
 
         ub_checks::assert_unsafe_precondition!(
             check_language_ub,
-            "ptr::sub_ptr requires `self >= origin`",
+            "ptr::offset_from_unsigned requires `self >= origin`",
             (
                 this: *const () = self as *const (),
                 origin: *const () = origin as *const (),
@@ -804,7 +804,7 @@ impl<T: ?Sized> *const T {
     /// units of **bytes**.
     ///
     /// This is purely a convenience for casting to a `u8` pointer and
-    /// using [`sub_ptr`][pointer::sub_ptr] on it. See that method for
+    /// using [`sub_ptr`][pointer::offset_from_unsigned] on it. See that method for
     /// documentation and safety requirements.
     ///
     /// For non-`Sized` pointees this operation considers only the data pointers,
@@ -813,9 +813,9 @@ impl<T: ?Sized> *const T {
     #[rustc_const_stable(feature = "const_ptr_sub_ptr", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
-    pub const unsafe fn byte_sub_ptr<U: ?Sized>(self, origin: *const U) -> usize {
+    pub const unsafe fn byte_offset_from_unsigned<U: ?Sized>(self, origin: *const U) -> usize {
         // SAFETY: the caller must uphold the safety contract for `sub_ptr`.
-        unsafe { self.cast::<u8>().sub_ptr(origin.cast::<u8>()) }
+        unsafe { self.cast::<u8>().offset_from_unsigned(origin.cast::<u8>()) }
     }
 
     /// Returns whether two pointers are guaranteed to be equal.

core/src/ptr/mut_ptr.rs

@@ -896,7 +896,7 @@ impl<T: ?Sized> *mut T {
     /// that their safety preconditions are met:
     /// ```rust
     /// # unsafe fn blah(ptr: *mut i32, origin: *mut i32, count: usize) -> bool { unsafe {
-    /// ptr.sub_ptr(origin) == count
+    /// ptr.offset_from_unsigned(origin) == count
     /// # &&
     /// origin.add(count) == ptr
     /// # &&
@@ -929,10 +929,10 @@ impl<T: ?Sized> *mut T {
     ///     let ptr1: *mut i32 = p.add(1);
     ///     let ptr2: *mut i32 = p.add(3);
     ///
-    ///     assert_eq!(ptr2.sub_ptr(ptr1), 2);
+    ///     assert_eq!(ptr2.offset_from_unsigned(ptr1), 2);
     ///     assert_eq!(ptr1.add(2), ptr2);
     ///     assert_eq!(ptr2.sub(2), ptr1);
-    ///     assert_eq!(ptr2.sub_ptr(ptr2), 0);
+    ///     assert_eq!(ptr2.offset_from_unsigned(ptr2), 0);
     /// }
     ///
     /// // This would be incorrect, as the pointers are not correctly ordered:
@@ -941,20 +941,20 @@ impl<T: ?Sized> *mut T {
     #[rustc_const_stable(feature = "const_ptr_sub_ptr", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
-    pub const unsafe fn sub_ptr(self, origin: *const T) -> usize
+    pub const unsafe fn offset_from_unsigned(self, origin: *const T) -> usize
     where
         T: Sized,
     {
         // SAFETY: the caller must uphold the safety contract for `sub_ptr`.
-        unsafe { (self as *const T).sub_ptr(origin) }
+        unsafe { (self as *const T).offset_from_unsigned(origin) }
     }
 
     /// Calculates the distance between two pointers within the same allocation, *where it's known that
     /// `self` is equal to or greater than `origin`*. The returned value is in
     /// units of **bytes**.
     ///
     /// This is purely a convenience for casting to a `u8` pointer and
-    /// using [`sub_ptr`][pointer::sub_ptr] on it. See that method for
+    /// using [`sub_ptr`][pointer::offset_from_unsigned] on it. See that method for
     /// documentation and safety requirements.
     ///
     /// For non-`Sized` pointees this operation considers only the data pointers,
@@ -963,9 +963,9 @@ impl<T: ?Sized> *mut T {
     #[rustc_const_stable(feature = "const_ptr_sub_ptr", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
-    pub const unsafe fn byte_sub_ptr<U: ?Sized>(self, origin: *mut U) -> usize {
+    pub const unsafe fn byte_offset_from_unsigned<U: ?Sized>(self, origin: *mut U) -> usize {
         // SAFETY: the caller must uphold the safety contract for `byte_sub_ptr`.
-        unsafe { (self as *const T).byte_sub_ptr(origin) }
+        unsafe { (self as *const T).byte_offset_from_unsigned(origin) }
     }
 
     /// Adds an unsigned offset to a pointer.

core/src/ptr/non_null.rs

@@ -857,7 +857,7 @@ impl<T: ?Sized> NonNull<T> {
     /// that their safety preconditions are met:
     /// ```rust
     /// # unsafe fn blah(ptr: std::ptr::NonNull<u32>, origin: std::ptr::NonNull<u32>, count: usize) -> bool { unsafe {
-    /// ptr.sub_ptr(origin) == count
+    /// ptr.offset_from_unsigned(origin) == count
     /// # &&
     /// origin.add(count) == ptr
     /// # &&
@@ -890,33 +890,33 @@ impl<T: ?Sized> NonNull<T> {
     /// let ptr1: NonNull<u32> = NonNull::from(&a[1]);
     /// let ptr2: NonNull<u32> = NonNull::from(&a[3]);
     /// unsafe {
-    ///     assert_eq!(ptr2.sub_ptr(ptr1), 2);
+    ///     assert_eq!(ptr2.offset_from_unsigned(ptr1), 2);
     ///     assert_eq!(ptr1.add(2), ptr2);
     ///     assert_eq!(ptr2.sub(2), ptr1);
-    ///     assert_eq!(ptr2.sub_ptr(ptr2), 0);
+    ///     assert_eq!(ptr2.offset_from_unsigned(ptr2), 0);
     /// }
     ///
     /// // This would be incorrect, as the pointers are not correctly ordered:
-    /// // ptr1.sub_ptr(ptr2)
+    /// // ptr1.offset_from_unsigned(ptr2)
     /// ```
     #[inline]
     #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
     #[stable(feature = "ptr_sub_ptr", since = "CURRENT_RUSTC_VERSION")]
     #[rustc_const_stable(feature = "const_ptr_sub_ptr", since = "CURRENT_RUSTC_VERSION")]
-    pub const unsafe fn sub_ptr(self, subtracted: NonNull<T>) -> usize
+    pub const unsafe fn offset_from_unsigned(self, subtracted: NonNull<T>) -> usize
     where
         T: Sized,
     {
         // SAFETY: the caller must uphold the safety contract for `sub_ptr`.
-        unsafe { self.as_ptr().sub_ptr(subtracted.as_ptr()) }
+        unsafe { self.as_ptr().offset_from_unsigned(subtracted.as_ptr()) }
     }
 
     /// Calculates the distance between two pointers within the same allocation, *where it's known that
     /// `self` is equal to or greater than `origin`*. The returned value is in
     /// units of **bytes**.
     ///
     /// This is purely a convenience for casting to a `u8` pointer and
-    /// using [`sub_ptr`][NonNull::sub_ptr] on it. See that method for
+    /// using [`sub_ptr`][NonNull::offset_from_unsigned] on it. See that method for
     /// documentation and safety requirements.
     ///
     /// For non-`Sized` pointees this operation considers only the data pointers,
@@ -925,9 +925,9 @@ impl<T: ?Sized> NonNull<T> {
     #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces
     #[stable(feature = "ptr_sub_ptr", since = "CURRENT_RUSTC_VERSION")]
     #[rustc_const_stable(feature = "const_ptr_sub_ptr", since = "CURRENT_RUSTC_VERSION")]
-    pub const unsafe fn byte_sub_ptr<U: ?Sized>(self, origin: NonNull<U>) -> usize {
+    pub const unsafe fn byte_offset_from_unsigned<U: ?Sized>(self, origin: NonNull<U>) -> usize {
         // SAFETY: the caller must uphold the safety contract for `byte_sub_ptr`.
-        unsafe { self.as_ptr().byte_sub_ptr(origin.as_ptr()) }
+        unsafe { self.as_ptr().byte_offset_from_unsigned(origin.as_ptr()) }
     }
 
     /// Reads the value from `self` without moving it. This leaves the

core/src/slice/iter/macros.rs

@@ -54,7 +54,7 @@ macro_rules! len {
                 // To get rid of some bounds checks (see `position`), we use ptr_sub instead of
                 // offset_from (Tested by `codegen/slice-position-bounds-check`.)
                 // SAFETY: by the type invariant pointers are aligned and `start <= end`
-                unsafe { end.sub_ptr($self.ptr) }
+                unsafe { end.offset_from_unsigned($self.ptr) }
             },
         )
     }};

core/src/slice/raw.rs

@@ -272,7 +272,7 @@ pub const fn from_mut<T>(s: &mut T) -> &mut [T] {
 #[rustc_const_unstable(feature = "const_slice_from_ptr_range", issue = "89792")]
 pub const unsafe fn from_ptr_range<'a, T>(range: Range<*const T>) -> &'a [T] {
     // SAFETY: the caller must uphold the safety contract for `from_ptr_range`.
-    unsafe { from_raw_parts(range.start, range.end.sub_ptr(range.start)) }
+    unsafe { from_raw_parts(range.start, range.end.offset_from_unsigned(range.start)) }
 }
 
 /// Forms a mutable slice from a pointer range.
@@ -342,5 +342,5 @@ pub const unsafe fn from_ptr_range<'a, T>(range: Range<*const T>) -> &'a [T] {
 #[rustc_const_unstable(feature = "const_slice_from_mut_ptr_range", issue = "89792")]
 pub const unsafe fn from_mut_ptr_range<'a, T>(range: Range<*mut T>) -> &'a mut [T] {
     // SAFETY: the caller must uphold the safety contract for `from_mut_ptr_range`.
-    unsafe { from_raw_parts_mut(range.start, range.end.sub_ptr(range.start)) }
+    unsafe { from_raw_parts_mut(range.start, range.end.offset_from_unsigned(range.start)) }
 }

core/src/slice/sort/shared/pivot.rs

@@ -31,9 +31,9 @@ pub fn choose_pivot<T, F: FnMut(&T, &T) -> bool>(v: &[T], is_less: &mut F) -> us
         let c = v_base.add(len_div_8 * 7); // [7*floor(n/8), 8*floor(n/8))
 
         if len < PSEUDO_MEDIAN_REC_THRESHOLD {
-            median3(&*a, &*b, &*c, is_less).sub_ptr(v_base)
+            median3(&*a, &*b, &*c, is_less).offset_from_unsigned(v_base)
         } else {
-            median3_rec(a, b, c, len_div_8, is_less).sub_ptr(v_base)
+            median3_rec(a, b, c, len_div_8, is_less).offset_from_unsigned(v_base)
         }
     }
 }

core/src/slice/sort/stable/merge.rs

@@ -143,7 +143,7 @@ impl<T> Drop for MergeState<T> {
         // leave the input slice `v` with each original element and all possible
         // modifications observed.
         unsafe {
-            let len = self.end.sub_ptr(self.start);
+            let len = self.end.offset_from_unsigned(self.start);
             ptr::copy_nonoverlapping(self.start, self.dst, len);
         }
     }

core/src/slice/sort/unstable/quicksort.rs

@@ -224,7 +224,7 @@ where
             left = left.add(1);
         }
 
-        left.sub_ptr(v_base)
+        left.offset_from_unsigned(v_base)
 
         // `gap_opt` goes out of scope and overwrites the last wrong-side element on the right side
         // with the first wrong-side element of the left side that was initially overwritten by the