Add references to the IEEE functions for float_next_up_down

Mention the IEEE function by name and create a doc alias of the same.

Author: tgross35

library/core/src/num/f128.rs

@@ -515,11 +515,14 @@ impl f128 {
     /// # }
     /// ```
     ///
+    /// This operation corresponds to IEEE-754 `nextUp`.
+    ///
     /// [`NEG_INFINITY`]: Self::NEG_INFINITY
     /// [`INFINITY`]: Self::INFINITY
     /// [`MIN`]: Self::MIN
     /// [`MAX`]: Self::MAX
     #[inline]
+    #[doc(alias = "nextUp")]
     #[unstable(feature = "f128", issue = "116909")]
     pub const fn next_up(self) -> Self {
         // Some targets violate Rust's assumption of IEEE semantics, e.g. by flushing
@@ -567,11 +570,14 @@ impl f128 {
     /// # }
     /// ```
     ///
+    /// This operation corresponds to IEEE-754 `nextDown`.
+    ///
     /// [`NEG_INFINITY`]: Self::NEG_INFINITY
     /// [`INFINITY`]: Self::INFINITY
     /// [`MIN`]: Self::MIN
     /// [`MAX`]: Self::MAX
     #[inline]
+    #[doc(alias = "nextDown")]
     #[unstable(feature = "f128", issue = "116909")]
     pub const fn next_down(self) -> Self {
         // Some targets violate Rust's assumption of IEEE semantics, e.g. by flushing

library/core/src/num/f16.rs

@@ -508,11 +508,14 @@ impl f16 {
     /// # }
     /// ```
     ///
+    /// This operation corresponds to IEEE-754 `nextUp`.
+    ///
     /// [`NEG_INFINITY`]: Self::NEG_INFINITY
     /// [`INFINITY`]: Self::INFINITY
     /// [`MIN`]: Self::MIN
     /// [`MAX`]: Self::MAX
     #[inline]
+    #[doc(alias = "nextUp")]
     #[unstable(feature = "f16", issue = "116909")]
     pub const fn next_up(self) -> Self {
         // Some targets violate Rust's assumption of IEEE semantics, e.g. by flushing
@@ -560,11 +563,14 @@ impl f16 {
     /// # }
     /// ```
     ///
+    /// This operation corresponds to IEEE-754 `nextDown`.
+    ///
     /// [`NEG_INFINITY`]: Self::NEG_INFINITY
     /// [`INFINITY`]: Self::INFINITY
     /// [`MIN`]: Self::MIN
     /// [`MAX`]: Self::MAX
     #[inline]
+    #[doc(alias = "nextDown")]
     #[unstable(feature = "f16", issue = "116909")]
     pub const fn next_down(self) -> Self {
         // Some targets violate Rust's assumption of IEEE semantics, e.g. by flushing

library/core/src/num/f32.rs

@@ -733,11 +733,14 @@ impl f32 {
     /// assert_eq!(16777216f32.next_up(), 16777218.0);
     /// ```
     ///
+    /// This operation corresponds to IEEE-754 `nextUp`.
+    ///
     /// [`NEG_INFINITY`]: Self::NEG_INFINITY
     /// [`INFINITY`]: Self::INFINITY
     /// [`MIN`]: Self::MIN
     /// [`MAX`]: Self::MAX
     #[inline]
+    #[doc(alias = "nextUp")]
     #[stable(feature = "float_next_up_down", since = "CURRENT_RUSTC_VERSION")]
     #[rustc_const_stable(feature = "float_next_up_down", since = "CURRENT_RUSTC_VERSION")]
     pub const fn next_up(self) -> Self {
@@ -781,11 +784,14 @@ impl f32 {
     /// assert_eq!(clamped.next_up(), 1.0);
     /// ```
     ///
+    /// This operation corresponds to IEEE-754 `nextDown`.
+    ///
     /// [`NEG_INFINITY`]: Self::NEG_INFINITY
     /// [`INFINITY`]: Self::INFINITY
     /// [`MIN`]: Self::MIN
     /// [`MAX`]: Self::MAX
     #[inline]
+    #[doc(alias = "nextDown")]
     #[stable(feature = "float_next_up_down", since = "CURRENT_RUSTC_VERSION")]
     #[rustc_const_stable(feature = "float_next_up_down", since = "CURRENT_RUSTC_VERSION")]
     pub const fn next_down(self) -> Self {

library/core/src/num/f64.rs

@@ -750,11 +750,14 @@ impl f64 {
     /// assert_eq!(9007199254740992f64.next_up(), 9007199254740994.0);
     /// ```
     ///
+    /// This operation corresponds to IEEE-754 `nextUp`.
+    ///
     /// [`NEG_INFINITY`]: Self::NEG_INFINITY
     /// [`INFINITY`]: Self::INFINITY
     /// [`MIN`]: Self::MIN
     /// [`MAX`]: Self::MAX
     #[inline]
+    #[doc(alias = "nextUp")]
     #[stable(feature = "float_next_up_down", since = "CURRENT_RUSTC_VERSION")]
     #[rustc_const_stable(feature = "float_next_up_down", since = "CURRENT_RUSTC_VERSION")]
     pub const fn next_up(self) -> Self {
@@ -798,11 +801,14 @@ impl f64 {
     /// assert_eq!(clamped.next_up(), 1.0);
     /// ```
     ///
+    /// This operation corresponds to IEEE-754 `nextDown`.
+    ///
     /// [`NEG_INFINITY`]: Self::NEG_INFINITY
     /// [`INFINITY`]: Self::INFINITY
     /// [`MIN`]: Self::MIN
     /// [`MAX`]: Self::MAX
     #[inline]
+    #[doc(alias = "nextDown")]
     #[stable(feature = "float_next_up_down", since = "CURRENT_RUSTC_VERSION")]
     #[rustc_const_stable(feature = "float_next_up_down", since = "CURRENT_RUSTC_VERSION")]
     pub const fn next_down(self) -> Self {