Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 666 insertions, 0 deletions

diff --git a/third_party/rust/atomic/src/ops.rs b/third_party/rust/atomic/src/ops.rs
new file mode 100644
index 0000000000..3626c9ed9a
--- /dev/null
+++ b/third_party/rust/atomic/src/ops.rs
@@ -0,0 +1,666 @@
+// Copyright 2016 Amanieu d'Antras
+//
+// Licensed under the Apache License, Version 2.0, <LICENSE-APACHE or
+// http://apache.org/licenses/LICENSE-2.0> or the MIT license <LICENSE-MIT or
+// http://opensource.org/licenses/MIT>, at your option. This file may not be
+// copied, modified, or distributed except according to those terms.
+
+use core::cmp;
+use core::mem;
+use core::num::Wrapping;
+use core::ops;
+use core::sync::atomic::Ordering;
+use fallback;
+
+#[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+use core::sync::atomic::{ AtomicI8, AtomicU8 };
+#[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+use core::sync::atomic::{ AtomicI16, AtomicU16 };
+#[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+use core::sync::atomic::{ AtomicI32, AtomicU32 };
+#[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+use core::sync::atomic::{ AtomicI64, AtomicU64 };
+
+#[cfg(not(feature = "nightly"))]
+use core::sync::atomic::AtomicUsize;
+#[cfg(not(feature = "nightly"))]
+const SIZEOF_USIZE: usize = mem::size_of::<usize>();
+#[cfg(not(feature = "nightly"))]
+const ALIGNOF_USIZE: usize = mem::align_of::<usize>();
+
+#[cfg(feature = "nightly")]
+#[inline]
+pub const fn atomic_is_lock_free<T>() -> bool {
+    let size = mem::size_of::<T>();
+    // FIXME: switch to … && … && … once that operator is supported in const functions
+    (1 == size.count_ones()) & (8 >= size) & (mem::align_of::<T>() >= size)
+}
+
+#[cfg(not(feature = "nightly"))]
+#[inline]
+pub fn atomic_is_lock_free<T>() -> bool {
+    let size = mem::size_of::<T>();
+    1 == size.count_ones() && SIZEOF_USIZE >= size && mem::align_of::<T>() >= ALIGNOF_USIZE
+}
+
+#[inline]
+pub unsafe fn atomic_load<T>(dst: *mut T, order: Ordering) -> T {
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            mem::transmute_copy(&(*(dst as *const AtomicU8)).load(order))
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            mem::transmute_copy(&(*(dst as *const AtomicU16)).load(order))
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            mem::transmute_copy(&(*(dst as *const AtomicU32)).load(order))
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            mem::transmute_copy(&(*(dst as *const AtomicU64)).load(order))
+        }
+        #[cfg(not(feature = "nightly"))]
+        SIZEOF_USIZE if mem::align_of::<T>() >= ALIGNOF_USIZE =>
+        {
+            mem::transmute_copy(&(*(dst as *const AtomicUsize)).load(order))
+        }
+        _ => fallback::atomic_load(dst),
+    }
+}
+
+#[inline]
+pub unsafe fn atomic_store<T>(dst: *mut T, val: T, order: Ordering) {
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            (*(dst as *const AtomicU8)).store(mem::transmute_copy(&val), order)
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            (*(dst as *const AtomicU16)).store(mem::transmute_copy(&val), order)
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            (*(dst as *const AtomicU32)).store(mem::transmute_copy(&val), order)
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            (*(dst as *const AtomicU64)).store(mem::transmute_copy(&val), order)
+        }
+        #[cfg(not(feature = "nightly"))]
+        SIZEOF_USIZE if mem::align_of::<T>() >= ALIGNOF_USIZE =>
+        {
+            (*(dst as *const AtomicUsize)).store(mem::transmute_copy(&val), order)
+        }
+        _ => fallback::atomic_store(dst, val),
+    }
+}
+
+#[inline]
+pub unsafe fn atomic_swap<T>(dst: *mut T, val: T, order: Ordering) -> T {
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            mem::transmute_copy(&(*(dst as *const AtomicU8)).swap(mem::transmute_copy(&val), order))
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU16)).swap(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU32)).swap(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU64)).swap(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(not(feature = "nightly"))]
+        SIZEOF_USIZE if mem::align_of::<T>() >= ALIGNOF_USIZE =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicUsize)).swap(mem::transmute_copy(&val), order),
+            )
+        }
+        _ => fallback::atomic_swap(dst, val),
+    }
+}
+
+#[inline]
+unsafe fn map_result<T, U>(r: Result<T, T>) -> Result<U, U> {
+    match r {
+        Ok(x) => Ok(mem::transmute_copy(&x)),
+        Err(x) => Err(mem::transmute_copy(&x)),
+    }
+}
+
+#[inline]
+pub unsafe fn atomic_compare_exchange<T>(
+    dst: *mut T,
+    current: T,
+    new: T,
+    success: Ordering,
+    failure: Ordering,
+) -> Result<T, T> {
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            map_result((*(dst as *const AtomicU8)).compare_exchange(
+                mem::transmute_copy(&current),
+                mem::transmute_copy(&new),
+                success,
+                failure,
+            ))
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            map_result((*(dst as *const AtomicU16)).compare_exchange(
+                mem::transmute_copy(&current),
+                mem::transmute_copy(&new),
+                success,
+                failure,
+            ))
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            map_result((*(dst as *const AtomicU32)).compare_exchange(
+                mem::transmute_copy(&current),
+                mem::transmute_copy(&new),
+                success,
+                failure,
+            ))
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            map_result((*(dst as *const AtomicU64)).compare_exchange(
+                mem::transmute_copy(&current),
+                mem::transmute_copy(&new),
+                success,
+                failure,
+            ))
+        }
+        #[cfg(not(feature = "nightly"))]
+        SIZEOF_USIZE if mem::align_of::<T>() >= ALIGNOF_USIZE =>
+        {
+            map_result((*(dst as *const AtomicUsize)).compare_exchange(
+                mem::transmute_copy(&current),
+                mem::transmute_copy(&new),
+                success,
+                failure,
+            ))
+        }
+        _ => fallback::atomic_compare_exchange(dst, current, new),
+    }
+}
+
+#[inline]
+pub unsafe fn atomic_compare_exchange_weak<T>(
+    dst: *mut T,
+    current: T,
+    new: T,
+    success: Ordering,
+    failure: Ordering,
+) -> Result<T, T> {
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            map_result((*(dst as *const AtomicU8)).compare_exchange_weak(
+                mem::transmute_copy(&current),
+                mem::transmute_copy(&new),
+                success,
+                failure,
+            ))
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            map_result((*(dst as *const AtomicU16)).compare_exchange_weak(
+                mem::transmute_copy(&current),
+                mem::transmute_copy(&new),
+                success,
+                failure,
+            ))
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            map_result((*(dst as *const AtomicU32)).compare_exchange_weak(
+                mem::transmute_copy(&current),
+                mem::transmute_copy(&new),
+                success,
+                failure,
+            ))
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            map_result((*(dst as *const AtomicU64)).compare_exchange_weak(
+                mem::transmute_copy(&current),
+                mem::transmute_copy(&new),
+                success,
+                failure,
+            ))
+        }
+        #[cfg(not(feature = "nightly"))]
+        SIZEOF_USIZE if mem::align_of::<T>() >= ALIGNOF_USIZE =>
+        {
+            map_result((*(dst as *const AtomicUsize)).compare_exchange_weak(
+                mem::transmute_copy(&current),
+                mem::transmute_copy(&new),
+                success,
+                failure,
+            ))
+        }
+        _ => fallback::atomic_compare_exchange(dst, current, new),
+    }
+}
+
+#[inline]
+pub unsafe fn atomic_add<T: Copy>(dst: *mut T, val: T, order: Ordering) -> T
+where
+    Wrapping<T>: ops::Add<Output = Wrapping<T>>,
+{
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU8)).fetch_add(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU16)).fetch_add(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU32)).fetch_add(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU64)).fetch_add(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(not(feature = "nightly"))]
+        SIZEOF_USIZE if mem::align_of::<T>() >= ALIGNOF_USIZE =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicUsize)).fetch_add(mem::transmute_copy(&val), order),
+            )
+        }
+        _ => fallback::atomic_add(dst, val),
+    }
+}
+
+#[inline]
+pub unsafe fn atomic_sub<T: Copy>(dst: *mut T, val: T, order: Ordering) -> T
+where
+    Wrapping<T>: ops::Sub<Output = Wrapping<T>>,
+{
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU8)).fetch_sub(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU16)).fetch_sub(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU32)).fetch_sub(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU64)).fetch_sub(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(not(feature = "nightly"))]
+        SIZEOF_USIZE if mem::align_of::<T>() >= ALIGNOF_USIZE =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicUsize)).fetch_sub(mem::transmute_copy(&val), order),
+            )
+        }
+        _ => fallback::atomic_sub(dst, val),
+    }
+}
+
+#[inline]
+pub unsafe fn atomic_and<T: Copy + ops::BitAnd<Output = T>>(
+    dst: *mut T,
+    val: T,
+    order: Ordering,
+) -> T {
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU8)).fetch_and(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU16)).fetch_and(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU32)).fetch_and(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU64)).fetch_and(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(not(feature = "nightly"))]
+        SIZEOF_USIZE if mem::align_of::<T>() >= ALIGNOF_USIZE =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicUsize)).fetch_and(mem::transmute_copy(&val), order),
+            )
+        }
+        _ => fallback::atomic_and(dst, val),
+    }
+}
+
+#[inline]
+pub unsafe fn atomic_or<T: Copy + ops::BitOr<Output = T>>(
+    dst: *mut T,
+    val: T,
+    order: Ordering,
+) -> T {
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU8)).fetch_or(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU16)).fetch_or(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU32)).fetch_or(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU64)).fetch_or(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(not(feature = "nightly"))]
+        SIZEOF_USIZE if mem::align_of::<T>() >= ALIGNOF_USIZE =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicUsize)).fetch_or(mem::transmute_copy(&val), order),
+            )
+        }
+        _ => fallback::atomic_or(dst, val),
+    }
+}
+
+#[inline]
+pub unsafe fn atomic_xor<T: Copy + ops::BitXor<Output = T>>(
+    dst: *mut T,
+    val: T,
+    order: Ordering,
+) -> T {
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU8)).fetch_xor(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU16)).fetch_xor(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU32)).fetch_xor(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU64)).fetch_xor(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(not(feature = "nightly"))]
+        SIZEOF_USIZE if mem::align_of::<T>() >= ALIGNOF_USIZE =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicUsize)).fetch_xor(mem::transmute_copy(&val), order),
+            )
+        }
+        _ => fallback::atomic_xor(dst, val),
+    }
+}
+
+#[inline]
+pub unsafe fn atomic_min<T: Copy + cmp::Ord>(dst: *mut T, val: T, order: Ordering) -> T {
+    // Silence warning, fetch_min is not stable yet
+    #[cfg(not(feature = "nightly"))]
+    let _ = order;
+
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicI8)).fetch_min(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicI16)).fetch_min(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicI32)).fetch_min(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicI64)).fetch_min(mem::transmute_copy(&val), order),
+            )
+        }
+        _ => fallback::atomic_min(dst, val),
+    }
+}
+
+#[inline]
+pub unsafe fn atomic_max<T: Copy + cmp::Ord>(dst: *mut T, val: T, order: Ordering) -> T {
+    // Silence warning, fetch_min is not stable yet
+    #[cfg(not(feature = "nightly"))]
+    let _ = order;
+
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicI8)).fetch_max(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicI16)).fetch_max(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicI32)).fetch_max(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicI64)).fetch_max(mem::transmute_copy(&val), order),
+            )
+        }
+        _ => fallback::atomic_max(dst, val),
+    }
+}
+
+#[inline]
+pub unsafe fn atomic_umin<T: Copy + cmp::Ord>(dst: *mut T, val: T, order: Ordering) -> T {
+    // Silence warning, fetch_min is not stable yet
+    #[cfg(not(feature = "nightly"))]
+    let _ = order;
+
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU8)).fetch_min(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU16)).fetch_min(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU32)).fetch_min(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU64)).fetch_min(mem::transmute_copy(&val), order),
+            )
+        }
+        _ => fallback::atomic_min(dst, val),
+    }
+}
+
+#[inline]
+pub unsafe fn atomic_umax<T: Copy + cmp::Ord>(dst: *mut T, val: T, order: Ordering) -> T {
+    // Silence warning, fetch_min is not stable yet
+    #[cfg(not(feature = "nightly"))]
+    let _ = order;
+
+    match mem::size_of::<T>() {
+        #[cfg(all(feature = "nightly", target_has_atomic = "8"))]
+        1 if mem::align_of::<T>() >= 1 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU8)).fetch_max(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "16"))]
+        2 if mem::align_of::<T>() >= 2 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU16)).fetch_max(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "32"))]
+        4 if mem::align_of::<T>() >= 4 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU32)).fetch_max(mem::transmute_copy(&val), order),
+            )
+        }
+        #[cfg(all(feature = "nightly", target_has_atomic = "64"))]
+        8 if mem::align_of::<T>() >= 8 =>
+        {
+            mem::transmute_copy(
+                &(*(dst as *const AtomicU64)).fetch_max(mem::transmute_copy(&val), order),
+            )
+        }
+        _ => fallback::atomic_max(dst, val),
+    }
+}