Added const versions of common numeric operations

rust-lang · Oct 14, 2021 · 3735575 · 3735575
1 parent eeb16a2
commit 3735575
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Showing 6 changed files with 234 additions and 107 deletions.
diff --git a/library/core/src/internal_macros.rs b/library/core/src/internal_macros.rs
@@ -5,6 +5,22 @@ macro_rules! forward_ref_unop {
         forward_ref_unop!(impl $imp, $method for $t,
                 #[stable(feature = "rust1", since = "1.0.0")]);
     };
+    (impl const $imp:ident, $method:ident for $t:ty) => {
+        forward_ref_unop!(impl const $imp, $method for $t,
+                #[stable(feature = "rust1", since = "1.0.0")]);
+    };
+    (impl const $imp:ident, $method:ident for $t:ty, #[$attr:meta]) => {
+        #[$attr]
+        #[rustc_const_unstable(feature = "const_ops", issue = "69420")]
+        impl const $imp for &$t {
+            type Output = <$t as $imp>::Output;
+
+            #[inline]
+            fn $method(self) -> <$t as $imp>::Output {
+                $imp::$method(*self)
+            }
+        }
+    };
     (impl $imp:ident, $method:ident for $t:ty, #[$attr:meta]) => {
         #[$attr]
         impl $imp for &$t {
@@ -25,6 +41,44 @@ macro_rules! forward_ref_binop {
         forward_ref_binop!(impl $imp, $method for $t, $u,
                 #[stable(feature = "rust1", since = "1.0.0")]);
     };
+    (impl const $imp:ident, $method:ident for $t:ty, $u:ty) => {
+        forward_ref_binop!(impl const $imp, $method for $t, $u,
+                #[stable(feature = "rust1", since = "1.0.0")]);
+    };
+    (impl const $imp:ident, $method:ident for $t:ty, $u:ty, #[$attr:meta]) => {
+        #[$attr]
+        #[rustc_const_unstable(feature = "const_ops", issue = "69420")]
+        impl<'a> const $imp<$u> for &'a $t {
+            type Output = <$t as $imp<$u>>::Output;
+
+            #[inline]
+            fn $method(self, other: $u) -> <$t as $imp<$u>>::Output {
+                $imp::$method(*self, other)
+            }
+        }
+
+        #[$attr]
+        #[rustc_const_unstable(feature = "const_ops", issue = "69420")]
+        impl const $imp<&$u> for $t {
+            type Output = <$t as $imp<$u>>::Output;
+
+            #[inline]
+            fn $method(self, other: &$u) -> <$t as $imp<$u>>::Output {
+                $imp::$method(self, *other)
+            }
+        }
+
+        #[$attr]
+        #[rustc_const_unstable(feature = "const_ops", issue = "69420")]
+        impl const $imp<&$u> for &$t {
+            type Output = <$t as $imp<$u>>::Output;
+
+            #[inline]
+            fn $method(self, other: &$u) -> <$t as $imp<$u>>::Output {
+                $imp::$method(*self, *other)
+            }
+        }
+    };
     (impl $imp:ident, $method:ident for $t:ty, $u:ty, #[$attr:meta]) => {
         #[$attr]
         impl<'a> $imp<$u> for &'a $t {
@@ -65,6 +119,20 @@ macro_rules! forward_ref_op_assign {
         forward_ref_op_assign!(impl $imp, $method for $t, $u,
                 #[stable(feature = "op_assign_builtins_by_ref", since = "1.22.0")]);
     };
+    (impl const $imp:ident, $method:ident for $t:ty, $u:ty) => {
+        forward_ref_op_assign!(impl const $imp, $method for $t, $u,
+                #[stable(feature = "op_assign_builtins_by_ref", since = "1.22.0")]);
+    };
+    (impl const $imp:ident, $method:ident for $t:ty, $u:ty, #[$attr:meta]) => {
+        #[$attr]
+        #[rustc_const_unstable(feature = "const_ops", issue = "69420")]
+        impl const $imp<&$u> for $t {
+            #[inline]
+            fn $method(&mut self, other: &$u) {
+                $imp::$method(self, *other);
+            }
+        }
+    };
     (impl $imp:ident, $method:ident for $t:ty, $u:ty, #[$attr:meta]) => {
         #[$attr]
         impl $imp<&$u> for $t {

diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs
@@ -115,6 +115,7 @@
 #![feature(const_likely)]
 #![feature(const_maybe_uninit_as_ptr)]
 #![feature(const_maybe_uninit_assume_init)]
+#![feature(const_ops)]
 #![feature(const_option)]
 #![feature(const_pin)]
 #![feature(const_replace)]

diff --git a/library/core/src/num/nonzero.rs b/library/core/src/num/nonzero.rs
@@ -82,7 +82,8 @@ macro_rules! nonzero_integers {
             }
 
             #[stable(feature = "from_nonzero", since = "1.31.0")]
-            impl From<$Ty> for $Int {
+            #[rustc_const_unstable(feature = "const_ops", issue = "69420")]
+            impl const From<$Ty> for $Int {
                 #[doc = concat!("Converts a `", stringify!($Ty), "` into an `", stringify!($Int), "`")]
                 #[inline]
                 fn from(nonzero: $Ty) -> Self {
@@ -91,7 +92,8 @@ macro_rules! nonzero_integers {
             }
 
             #[stable(feature = "nonzero_bitor", since = "1.45.0")]
-            impl BitOr for $Ty {
+            #[rustc_const_unstable(feature = "const_ops", issue = "69420")]
+            impl const BitOr for $Ty {
                 type Output = Self;
                 #[inline]
                 fn bitor(self, rhs: Self) -> Self::Output {
@@ -102,7 +104,8 @@ macro_rules! nonzero_integers {
             }
 
             #[stable(feature = "nonzero_bitor", since = "1.45.0")]
-            impl BitOr<$Int> for $Ty {
+            #[rustc_const_unstable(feature = "const_ops", issue = "69420")]
+            impl const BitOr<$Int> for $Ty {
                 type Output = Self;
                 #[inline]
                 fn bitor(self, rhs: $Int) -> Self::Output {
@@ -114,7 +117,8 @@ macro_rules! nonzero_integers {
             }
 
             #[stable(feature = "nonzero_bitor", since = "1.45.0")]
-            impl BitOr<$Ty> for $Int {
+            #[rustc_const_unstable(feature = "const_ops", issue = "69420")]
+            impl const BitOr<$Ty> for $Int {
                 type Output = $Ty;
                 #[inline]
                 fn bitor(self, rhs: $Ty) -> Self::Output {
@@ -126,15 +130,17 @@ macro_rules! nonzero_integers {
             }
 
             #[stable(feature = "nonzero_bitor", since = "1.45.0")]
-            impl BitOrAssign for $Ty {
+            #[rustc_const_unstable(feature = "const_ops", issue = "69420")]
+            impl const BitOrAssign for $Ty {
                 #[inline]
                 fn bitor_assign(&mut self, rhs: Self) {
                     *self = *self | rhs;
                 }
             }
 
             #[stable(feature = "nonzero_bitor", since = "1.45.0")]
-            impl BitOrAssign<$Int> for $Ty {
+            #[rustc_const_unstable(feature = "const_ops", issue = "69420")]
+            impl const BitOrAssign<$Int> for $Ty {
                 #[inline]
                 fn bitor_assign(&mut self, rhs: $Int) {
                     *self = *self | rhs;
@@ -256,7 +262,8 @@ macro_rules! nonzero_integers_div {
     ( $( $Ty: ident($Int: ty); )+ ) => {
         $(
             #[stable(feature = "nonzero_div", since = "1.51.0")]
-            impl Div<$Ty> for $Int {
+            #[rustc_const_unstable(feature = "const_ops", issue = "69420")]
+            impl const Div<$Ty> for $Int {
                 type Output = $Int;
                 /// This operation rounds towards zero,
                 /// truncating any fractional part of the exact result, and cannot panic.
@@ -269,7 +276,8 @@ macro_rules! nonzero_integers_div {
             }
 
             #[stable(feature = "nonzero_div", since = "1.51.0")]
-            impl Rem<$Ty> for $Int {
+            #[rustc_const_unstable(feature = "const_ops", issue = "69420")]
+            impl const Rem<$Ty> for $Int {
                 type Output = $Int;
                 /// This operation satisfies `n % d == n - (n / d) * d`, and cannot panic.
                 #[inline]