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make abs, wrapping_abs, and overflowing_abs const functions

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This commit is contained in:
Trevor Spiteri 2019-08-21 14:10:40 +02:00
parent bea0372a1a
commit 39260d9016
1 changed files with 9 additions and 21 deletions
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30
src/libcore/num/mod.rs
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@ -1401,12 +1401,8 @@ $EndFeature, "
```"),
#[stable(feature = "no_panic_abs", since = "1.13.0")]
#[inline]
pub fn wrapping_abs(self) -> Self {
if self.is_negative() {
self.wrapping_neg()
} else {
self
}
pub const fn wrapping_abs(self) -> Self {
(self ^ (self >> ($BITS - 1))).wrapping_sub(self >> ($BITS - 1))
}
}
@ -1764,12 +1760,8 @@ $EndFeature, "
```"),
#[stable(feature = "no_panic_abs", since = "1.13.0")]
#[inline]
pub fn overflowing_abs(self) -> (Self, bool) {
if self.is_negative() {
self.overflowing_neg()
} else {
(self, false)
}
pub const fn overflowing_abs(self) -> (Self, bool) {
(self ^ (self >> ($BITS - 1))).overflowing_sub(self >> ($BITS - 1))
}
}
@ -1973,15 +1965,11 @@ $EndFeature, "
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
#[rustc_inherit_overflow_checks]
pub fn abs(self) -> Self {
if self.is_negative() {
// Note that the #[inline] above means that the overflow
// semantics of this negation depend on the crate we're being
// inlined into.
-self
} else {
self
}
pub const fn abs(self) -> Self {
// Note that the #[inline] above means that the overflow
// semantics of the subtraction depend on the crate we're being
// inlined into.
(self ^ (self >> ($BITS - 1))) - (self >> ($BITS - 1))
}
}