Improve generic type name

Co-authored-by: Jubilee <[email protected]>

Author: calebzulawski

library/core/src/intrinsics/simd.rs

@@ -194,20 +194,20 @@ extern "platform-intrinsic" {
     ///
     /// For each pointer in `ptr`, if the corresponding value in `mask` is `!0`, read the pointer.
     /// Otherwise if the corresponding value in `mask` is `0`, return the corresponding value from
-    /// `val`.
+    /// `defaults`.
     ///
     /// `T` must be a vector.
     ///
     /// `U` must be a vector of pointers to the element type of `T`, with the same length as `T`.
     ///
-    /// `V` must be a vector of integers with the same length as `T` (but any element size).
+    /// `M` must be a vector of integers with the same length as `T` (but any element size).
     ///
     /// # Safety
     /// Unmasked values in `T` must be readable as if by `<ptr>::read` (e.g. aligned to the element
     /// type).
     ///
     /// `mask` must only contain `0` or `!0` values.
-    pub fn simd_gather<T, U, V>(val: T, ptr: U, mask: V) -> T;
+    pub fn simd_gather<T, U, M>(val: T, ptr: U, mask: M) -> T;
 
     /// Write to a vector of pointers.
     ///