New upstream version 1.52.0~beta.3+dfsg1

[rustc.git] / library / core / src / num / mod.rs

diff --git a/library/core/src/num/mod.rs b/library/core/src/num/mod.rs
index 6bdfa18fa434ccf8ccf53a9f1499b22bf40c986c..f0bd976ba83d5599fc7c744f11ca5398f27d0a8a 100644 (file)
--- a/library/core/src/num/mod.rs
+++ b/library/core/src/num/mod.rs
@@ -152,6 +152,9 @@ impl isize {
      usize_isize_to_xe_bytes_doc!(), usize_isize_from_xe_bytes_doc!() }
 }
 
+/// If 6th bit set ascii is upper case.
+const ASCII_CASE_MASK: u8 = 0b0010_0000;
+
 #[lang = "u8"]
 impl u8 {
     uint_impl! { u8, u8, 8, 255, 2, "0x82", "0xa", "0x12", "0x12", "0x48", "[0x12]",
@@ -190,12 +193,13 @@ impl u8 {
     /// assert_eq!(65, lowercase_a.to_ascii_uppercase());
     /// ```
     ///
-    /// [`make_ascii_uppercase`]: #method.make_ascii_uppercase
+    /// [`make_ascii_uppercase`]: Self::make_ascii_uppercase
     #[stable(feature = "ascii_methods_on_intrinsics", since = "1.23.0")]
+    #[rustc_const_stable(feature = "const_ascii_methods_on_intrinsics", since = "1.52.0")]
     #[inline]
-    pub fn to_ascii_uppercase(&self) -> u8 {
+    pub const fn to_ascii_uppercase(&self) -> u8 {
         // Unset the fifth bit if this is a lowercase letter
-        *self & !((self.is_ascii_lowercase() as u8) << 5)
+        *self & !((self.is_ascii_lowercase() as u8) * ASCII_CASE_MASK)
     }
 
     /// Makes a copy of the value in its ASCII lower case equivalent.
@@ -213,12 +217,19 @@ impl u8 {
     /// assert_eq!(97, uppercase_a.to_ascii_lowercase());
     /// ```
     ///
-    /// [`make_ascii_lowercase`]: #method.make_ascii_lowercase
+    /// [`make_ascii_lowercase`]: Self::make_ascii_lowercase
     #[stable(feature = "ascii_methods_on_intrinsics", since = "1.23.0")]
+    #[rustc_const_stable(feature = "const_ascii_methods_on_intrinsics", since = "1.52.0")]
     #[inline]
-    pub fn to_ascii_lowercase(&self) -> u8 {
+    pub const fn to_ascii_lowercase(&self) -> u8 {
         // Set the fifth bit if this is an uppercase letter
-        *self | ((self.is_ascii_uppercase() as u8) << 5)
+        *self | (self.is_ascii_uppercase() as u8 * ASCII_CASE_MASK)
+    }
+
+    /// Assumes self is ascii
+    #[inline]
+    pub(crate) const fn ascii_change_case_unchecked(&self) -> u8 {
+        *self ^ ASCII_CASE_MASK
     }
 
     /// Checks that two values are an ASCII case-insensitive match.
@@ -234,8 +245,9 @@ impl u8 {
     /// assert!(lowercase_a.eq_ignore_ascii_case(&uppercase_a));
     /// ```
     #[stable(feature = "ascii_methods_on_intrinsics", since = "1.23.0")]
+    #[rustc_const_stable(feature = "const_ascii_methods_on_intrinsics", since = "1.52.0")]
     #[inline]
-    pub fn eq_ignore_ascii_case(&self, other: &u8) -> bool {
+    pub const fn eq_ignore_ascii_case(&self, other: &u8) -> bool {
         self.to_ascii_lowercase() == other.to_ascii_lowercase()
     }
 
@@ -257,7 +269,7 @@ impl u8 {
     /// assert_eq!(b'A', byte);
     /// ```
     ///
-    /// [`to_ascii_uppercase`]: #method.to_ascii_uppercase
+    /// [`to_ascii_uppercase`]: Self::to_ascii_uppercase
     #[stable(feature = "ascii_methods_on_intrinsics", since = "1.23.0")]
     #[inline]
     pub fn make_ascii_uppercase(&mut self) {
@@ -282,7 +294,7 @@ impl u8 {
     /// assert_eq!(b'a', byte);
     /// ```
     ///
-    /// [`to_ascii_lowercase`]: #method.to_ascii_lowercase
+    /// [`to_ascii_lowercase`]: Self::to_ascii_lowercase
     #[stable(feature = "ascii_methods_on_intrinsics", since = "1.23.0")]
     #[inline]
     pub fn make_ascii_lowercase(&mut self) {
@@ -714,9 +726,6 @@ impl usize {
 /// This `enum` is used as the return type for [`f32::classify`] and [`f64::classify`]. See
 /// their documentation for more.
 ///
-/// [`f32::classify`]: ../../std/primitive.f32.html#method.classify
-/// [`f64::classify`]: ../../std/primitive.f64.html#method.classify
-///
 /// # Examples
 ///
 /// ```