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-rw-r--r--vendor/crossbeam-utils/src/atomic/mod.rs37
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diff --git a/vendor/crossbeam-utils/src/atomic/mod.rs b/vendor/crossbeam-utils/src/atomic/mod.rs
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+//! Atomic types.
+//!
+//! * [`AtomicCell`], a thread-safe mutable memory location.
+//! * [`AtomicConsume`], for reading from primitive atomic types with "consume" ordering.
+
+#[cfg(target_has_atomic = "ptr")]
+#[cfg(not(crossbeam_loom))]
+cfg_if::cfg_if! {
+ // Use "wide" sequence lock if the pointer width <= 32 for preventing its counter against wrap
+ // around.
+ //
+ // We are ignoring too wide architectures (pointer width >= 256), since such a system will not
+ // appear in a conceivable future.
+ //
+ // In narrow architectures (pointer width <= 16), the counter is still <= 32-bit and may be
+ // vulnerable to wrap around. But it's mostly okay, since in such a primitive hardware, the
+ // counter will not be increased that fast.
+ if #[cfg(any(target_pointer_width = "64", target_pointer_width = "128"))] {
+ mod seq_lock;
+ } else {
+ #[path = "seq_lock_wide.rs"]
+ mod seq_lock;
+ }
+}
+
+#[cfg(target_has_atomic = "ptr")]
+// We cannot provide AtomicCell under cfg(crossbeam_loom) because loom's atomic
+// types have a different in-memory representation than the underlying type.
+// TODO: The latest loom supports fences, so fallback using seqlock may be available.
+#[cfg(not(crossbeam_loom))]
+mod atomic_cell;
+mod consume;
+
+#[cfg(target_has_atomic = "ptr")]
+#[cfg(not(crossbeam_loom))]
+pub use self::atomic_cell::AtomicCell;
+pub use self::consume::AtomicConsume;