Rollup merge of #130822 - bjoernager:non-null-from-ref, r=dtolnay

Add `from_ref` and `from_mut` constructors to `core::ptr::NonNull`.

Relevant tracking issue: #130823

The `core::ptr::NonNull` type should have the convenience constructors `from_ref` and `from_mut` for parity with `core::ptr::from_ref` and `core::ptr::from_mut`.

Although the type in question already implements `From<&T>` and `From<&mut T>`, these new functions also carry the ability to be used in constant expressions (due to not being behind a trait).

6 files changed, 74 insertions, 62 deletions

diff --git a/tests/mir-opt/pre-codegen/slice_iter.enumerated_loop.PreCodegen.after.panic-abort.mir b/tests/mir-opt/pre-codegen/slice_iter.enumerated_loop.PreCodegen.after.panic-abort.mir
index 3aa483ed1ae..bd56ab67e00 100644
--- a/tests/mir-opt/pre-codegen/slice_iter.enumerated_loop.PreCodegen.after.panic-abort.mir
+++ b/tests/mir-opt/pre-codegen/slice_iter.enumerated_loop.PreCodegen.after.panic-abort.mir
@@ -19,30 +19,30 @@ fn enumerated_loop(_1: &[T], _2: impl Fn(usize, &T)) -> () {
             debug i => _22;
             debug x => _23;
         }
-        scope 17 (inlined <Enumerate<std::slice::Iter<'_, T>> as Iterator>::next) {
+        scope 18 (inlined <Enumerate<std::slice::Iter<'_, T>> as Iterator>::next) {
             let mut _14: &mut std::slice::Iter<'_, T>;
             let mut _15: std::option::Option<&T>;
             let mut _19: (usize, bool);
             let mut _20: (usize, &T);
-            scope 18 {
+            scope 19 {
                 let _18: usize;
-                scope 23 {
+                scope 24 {
                 }
             }
-            scope 19 {
-                scope 20 {
-                    scope 26 (inlined <Option<(usize, &T)> as FromResidual<Option<Infallible>>>::from_residual) {
+            scope 20 {
+                scope 21 {
+                    scope 27 (inlined <Option<(usize, &T)> as FromResidual<Option<Infallible>>>::from_residual) {
                     }
                 }
             }
-            scope 21 {
-                scope 22 {
+            scope 22 {
+                scope 23 {
                 }
             }
-            scope 24 (inlined <Option<&T> as Try>::branch) {
+            scope 25 (inlined <Option<&T> as Try>::branch) {
                 let mut _16: isize;
                 let _17: &T;
-                scope 25 {
+                scope 26 {
                 }
             }
         }
@@ -59,29 +59,31 @@ fn enumerated_loop(_1: &[T], _2: impl Fn(usize, &T)) -> () {
                     let _9: *const T;
                     scope 7 {
                     }
-                    scope 11 (inlined without_provenance::<T>) {
+                    scope 12 (inlined without_provenance::<T>) {
                     }
-                    scope 12 (inlined NonNull::<T>::as_ptr) {
+                    scope 13 (inlined NonNull::<T>::as_ptr) {
                     }
-                    scope 13 (inlined std::ptr::mut_ptr::<impl *mut T>::add) {
+                    scope 14 (inlined std::ptr::mut_ptr::<impl *mut T>::add) {
                     }
                 }
                 scope 8 (inlined <NonNull<[T]> as From<&[T]>>::from) {
-                    let mut _4: *const [T];
+                    scope 9 (inlined NonNull::<[T]>::from_ref) {
+                        let mut _4: *const [T];
+                    }
                 }
-                scope 9 (inlined NonNull::<[T]>::cast::<T>) {
+                scope 10 (inlined NonNull::<[T]>::cast::<T>) {
                     let mut _5: *const T;
-                    scope 10 (inlined NonNull::<[T]>::as_ptr) {
+                    scope 11 (inlined NonNull::<[T]>::as_ptr) {
                     }
                 }
             }
         }
     }
-    scope 14 (inlined <std::slice::Iter<'_, T> as Iterator>::enumerate) {
-        scope 15 (inlined Enumerate::<std::slice::Iter<'_, T>>::new) {
+    scope 15 (inlined <std::slice::Iter<'_, T> as Iterator>::enumerate) {
+        scope 16 (inlined Enumerate::<std::slice::Iter<'_, T>>::new) {
         }
     }
-    scope 16 (inlined <Enumerate<std::slice::Iter<'_, T>> as IntoIterator>::into_iter) {
+    scope 17 (inlined <Enumerate<std::slice::Iter<'_, T>> as IntoIterator>::into_iter) {
     }
 
     bb0: {
diff --git a/tests/mir-opt/pre-codegen/slice_iter.enumerated_loop.PreCodegen.after.panic-unwind.mir b/tests/mir-opt/pre-codegen/slice_iter.enumerated_loop.PreCodegen.after.panic-unwind.mir
index 4cc0aa0ed78..57f09a4631b 100644
--- a/tests/mir-opt/pre-codegen/slice_iter.enumerated_loop.PreCodegen.after.panic-unwind.mir
+++ b/tests/mir-opt/pre-codegen/slice_iter.enumerated_loop.PreCodegen.after.panic-unwind.mir
@@ -34,29 +34,31 @@ fn enumerated_loop(_1: &[T], _2: impl Fn(usize, &T)) -> () {
                     let _9: *const T;
                     scope 7 {
                     }
-                    scope 11 (inlined without_provenance::<T>) {
+                    scope 12 (inlined without_provenance::<T>) {
                     }
-                    scope 12 (inlined NonNull::<T>::as_ptr) {
+                    scope 13 (inlined NonNull::<T>::as_ptr) {
                     }
-                    scope 13 (inlined std::ptr::mut_ptr::<impl *mut T>::add) {
+                    scope 14 (inlined std::ptr::mut_ptr::<impl *mut T>::add) {
                     }
                 }
                 scope 8 (inlined <NonNull<[T]> as From<&[T]>>::from) {
-                    let mut _4: *const [T];
+                    scope 9 (inlined NonNull::<[T]>::from_ref) {
+                        let mut _4: *const [T];
+                    }
                 }
-                scope 9 (inlined NonNull::<[T]>::cast::<T>) {
+                scope 10 (inlined NonNull::<[T]>::cast::<T>) {
                     let mut _5: *const T;
-                    scope 10 (inlined NonNull::<[T]>::as_ptr) {
+                    scope 11 (inlined NonNull::<[T]>::as_ptr) {
                     }
                 }
             }
         }
     }
-    scope 14 (inlined <std::slice::Iter<'_, T> as Iterator>::enumerate) {
-        scope 15 (inlined Enumerate::<std::slice::Iter<'_, T>>::new) {
+    scope 15 (inlined <std::slice::Iter<'_, T> as Iterator>::enumerate) {
+        scope 16 (inlined Enumerate::<std::slice::Iter<'_, T>>::new) {
         }
     }
-    scope 16 (inlined <Enumerate<std::slice::Iter<'_, T>> as IntoIterator>::into_iter) {
+    scope 17 (inlined <Enumerate<std::slice::Iter<'_, T>> as IntoIterator>::into_iter) {
     }
 
     bb0: {
diff --git a/tests/mir-opt/pre-codegen/slice_iter.forward_loop.PreCodegen.after.panic-abort.mir b/tests/mir-opt/pre-codegen/slice_iter.forward_loop.PreCodegen.after.panic-abort.mir
index 507afa63c68..4050304f469 100644
--- a/tests/mir-opt/pre-codegen/slice_iter.forward_loop.PreCodegen.after.panic-abort.mir
+++ b/tests/mir-opt/pre-codegen/slice_iter.forward_loop.PreCodegen.after.panic-abort.mir
@@ -31,25 +31,27 @@ fn forward_loop(_1: &[T], _2: impl Fn(&T)) -> () {
                     let _9: *const T;
                     scope 7 {
                     }
-                    scope 11 (inlined without_provenance::<T>) {
+                    scope 12 (inlined without_provenance::<T>) {
                     }
-                    scope 12 (inlined NonNull::<T>::as_ptr) {
+                    scope 13 (inlined NonNull::<T>::as_ptr) {
                     }
-                    scope 13 (inlined std::ptr::mut_ptr::<impl *mut T>::add) {
+                    scope 14 (inlined std::ptr::mut_ptr::<impl *mut T>::add) {
                     }
                 }
                 scope 8 (inlined <NonNull<[T]> as From<&[T]>>::from) {
-                    let mut _4: *const [T];
+                    scope 9 (inlined NonNull::<[T]>::from_ref) {
+                        let mut _4: *const [T];
+                    }
                 }
-                scope 9 (inlined NonNull::<[T]>::cast::<T>) {
+                scope 10 (inlined NonNull::<[T]>::cast::<T>) {
                     let mut _5: *const T;
-                    scope 10 (inlined NonNull::<[T]>::as_ptr) {
+                    scope 11 (inlined NonNull::<[T]>::as_ptr) {
                     }
                 }
             }
         }
     }
-    scope 14 (inlined <std::slice::Iter<'_, T> as IntoIterator>::into_iter) {
+    scope 15 (inlined <std::slice::Iter<'_, T> as IntoIterator>::into_iter) {
     }
 
     bb0: {
diff --git a/tests/mir-opt/pre-codegen/slice_iter.forward_loop.PreCodegen.after.panic-unwind.mir b/tests/mir-opt/pre-codegen/slice_iter.forward_loop.PreCodegen.after.panic-unwind.mir
index a25f12edc28..2c3d7ab1e4a 100644
--- a/tests/mir-opt/pre-codegen/slice_iter.forward_loop.PreCodegen.after.panic-unwind.mir
+++ b/tests/mir-opt/pre-codegen/slice_iter.forward_loop.PreCodegen.after.panic-unwind.mir
@@ -31,25 +31,27 @@ fn forward_loop(_1: &[T], _2: impl Fn(&T)) -> () {
                     let _9: *const T;
                     scope 7 {
                     }
-                    scope 11 (inlined without_provenance::<T>) {
+                    scope 12 (inlined without_provenance::<T>) {
                     }
-                    scope 12 (inlined NonNull::<T>::as_ptr) {
+                    scope 13 (inlined NonNull::<T>::as_ptr) {
                     }
-                    scope 13 (inlined std::ptr::mut_ptr::<impl *mut T>::add) {
+                    scope 14 (inlined std::ptr::mut_ptr::<impl *mut T>::add) {
                     }
                 }
                 scope 8 (inlined <NonNull<[T]> as From<&[T]>>::from) {
-                    let mut _4: *const [T];
+                    scope 9 (inlined NonNull::<[T]>::from_ref) {
+                        let mut _4: *const [T];
+                    }
                 }
-                scope 9 (inlined NonNull::<[T]>::cast::<T>) {
+                scope 10 (inlined NonNull::<[T]>::cast::<T>) {
                     let mut _5: *const T;
-                    scope 10 (inlined NonNull::<[T]>::as_ptr) {
+                    scope 11 (inlined NonNull::<[T]>::as_ptr) {
                     }
                 }
             }
         }
     }
-    scope 14 (inlined <std::slice::Iter<'_, T> as IntoIterator>::into_iter) {
+    scope 15 (inlined <std::slice::Iter<'_, T> as IntoIterator>::into_iter) {
     }
 
     bb0: {
diff --git a/tests/mir-opt/pre-codegen/slice_iter.reverse_loop.PreCodegen.after.panic-abort.mir b/tests/mir-opt/pre-codegen/slice_iter.reverse_loop.PreCodegen.after.panic-abort.mir
index 1b397a4e4cd..a6ccd435c40 100644
--- a/tests/mir-opt/pre-codegen/slice_iter.reverse_loop.PreCodegen.after.panic-abort.mir
+++ b/tests/mir-opt/pre-codegen/slice_iter.reverse_loop.PreCodegen.after.panic-abort.mir
@@ -18,7 +18,7 @@ fn reverse_loop(_1: &[T], _2: impl Fn(&T)) -> () {
         scope 2 {
             debug x => _17;
         }
-        scope 17 (inlined <Rev<std::slice::Iter<'_, T>> as Iterator>::next) {
+        scope 18 (inlined <Rev<std::slice::Iter<'_, T>> as Iterator>::next) {
             let mut _14: &mut std::slice::Iter<'_, T>;
         }
     }
@@ -34,29 +34,31 @@ fn reverse_loop(_1: &[T], _2: impl Fn(&T)) -> () {
                     let _9: *const T;
                     scope 7 {
                     }
-                    scope 11 (inlined without_provenance::<T>) {
+                    scope 12 (inlined without_provenance::<T>) {
                     }
-                    scope 12 (inlined NonNull::<T>::as_ptr) {
+                    scope 13 (inlined NonNull::<T>::as_ptr) {
                     }
-                    scope 13 (inlined std::ptr::mut_ptr::<impl *mut T>::add) {
+                    scope 14 (inlined std::ptr::mut_ptr::<impl *mut T>::add) {
                     }
                 }
                 scope 8 (inlined <NonNull<[T]> as From<&[T]>>::from) {
-                    let mut _4: *const [T];
+                    scope 9 (inlined NonNull::<[T]>::from_ref) {
+                        let mut _4: *const [T];
+                    }
                 }
-                scope 9 (inlined NonNull::<[T]>::cast::<T>) {
+                scope 10 (inlined NonNull::<[T]>::cast::<T>) {
                     let mut _5: *const T;
-                    scope 10 (inlined NonNull::<[T]>::as_ptr) {
+                    scope 11 (inlined NonNull::<[T]>::as_ptr) {
                     }
                 }
             }
         }
     }
-    scope 14 (inlined <std::slice::Iter<'_, T> as Iterator>::rev) {
-        scope 15 (inlined Rev::<std::slice::Iter<'_, T>>::new) {
+    scope 15 (inlined <std::slice::Iter<'_, T> as Iterator>::rev) {
+        scope 16 (inlined Rev::<std::slice::Iter<'_, T>>::new) {
         }
     }
-    scope 16 (inlined <Rev<std::slice::Iter<'_, T>> as IntoIterator>::into_iter) {
+    scope 17 (inlined <Rev<std::slice::Iter<'_, T>> as IntoIterator>::into_iter) {
     }
 
     bb0: {
diff --git a/tests/mir-opt/pre-codegen/slice_iter.reverse_loop.PreCodegen.after.panic-unwind.mir b/tests/mir-opt/pre-codegen/slice_iter.reverse_loop.PreCodegen.after.panic-unwind.mir
index 77689dd9b51..df11c8e3b49 100644
--- a/tests/mir-opt/pre-codegen/slice_iter.reverse_loop.PreCodegen.after.panic-unwind.mir
+++ b/tests/mir-opt/pre-codegen/slice_iter.reverse_loop.PreCodegen.after.panic-unwind.mir
@@ -18,7 +18,7 @@ fn reverse_loop(_1: &[T], _2: impl Fn(&T)) -> () {
         scope 2 {
             debug x => _17;
         }
-        scope 17 (inlined <Rev<std::slice::Iter<'_, T>> as Iterator>::next) {
+        scope 18 (inlined <Rev<std::slice::Iter<'_, T>> as Iterator>::next) {
             let mut _14: &mut std::slice::Iter<'_, T>;
         }
     }
@@ -34,29 +34,31 @@ fn reverse_loop(_1: &[T], _2: impl Fn(&T)) -> () {
                     let _9: *const T;
                     scope 7 {
                     }
-                    scope 11 (inlined without_provenance::<T>) {
+                    scope 12 (inlined without_provenance::<T>) {
                     }
-                    scope 12 (inlined NonNull::<T>::as_ptr) {
+                    scope 13 (inlined NonNull::<T>::as_ptr) {
                     }
-                    scope 13 (inlined std::ptr::mut_ptr::<impl *mut T>::add) {
+                    scope 14 (inlined std::ptr::mut_ptr::<impl *mut T>::add) {
                     }
                 }
                 scope 8 (inlined <NonNull<[T]> as From<&[T]>>::from) {
-                    let mut _4: *const [T];
+                    scope 9 (inlined NonNull::<[T]>::from_ref) {
+                        let mut _4: *const [T];
+                    }
                 }
-                scope 9 (inlined NonNull::<[T]>::cast::<T>) {
+                scope 10 (inlined NonNull::<[T]>::cast::<T>) {
                     let mut _5: *const T;
-                    scope 10 (inlined NonNull::<[T]>::as_ptr) {
+                    scope 11 (inlined NonNull::<[T]>::as_ptr) {
                     }
                 }
             }
         }
     }
-    scope 14 (inlined <std::slice::Iter<'_, T> as Iterator>::rev) {
-        scope 15 (inlined Rev::<std::slice::Iter<'_, T>>::new) {
+    scope 15 (inlined <std::slice::Iter<'_, T> as Iterator>::rev) {
+        scope 16 (inlined Rev::<std::slice::Iter<'_, T>>::new) {
         }
     }
-    scope 16 (inlined <Rev<std::slice::Iter<'_, T>> as IntoIterator>::into_iter) {
+    scope 17 (inlined <Rev<std::slice::Iter<'_, T>> as IntoIterator>::into_iter) {
     }
 
     bb0: {