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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 12:41:41 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-04 12:41:41 +0000
commit10ee2acdd26a7f1298c6f6d6b7af9b469fe29b87 (patch)
treebdffd5d80c26cf4a7a518281a204be1ace85b4c1 /vendor/crypto-bigint/src/limb.rs
parentReleasing progress-linux version 1.70.0+dfsg1-9~progress7.99u1. (diff)
downloadrustc-10ee2acdd26a7f1298c6f6d6b7af9b469fe29b87.tar.xz
rustc-10ee2acdd26a7f1298c6f6d6b7af9b469fe29b87.zip
Merging upstream version 1.70.0+dfsg2.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vendor/crypto-bigint/src/limb.rs')
-rw-r--r--vendor/crypto-bigint/src/limb.rs189
1 files changed, 189 insertions, 0 deletions
diff --git a/vendor/crypto-bigint/src/limb.rs b/vendor/crypto-bigint/src/limb.rs
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+//! Big integers are represented as an array of smaller CPU word-size integers
+//! called "limbs".
+
+#![allow(clippy::derive_hash_xor_eq)]
+
+mod add;
+mod bit_and;
+mod bit_not;
+mod bit_or;
+mod bit_xor;
+mod bits;
+mod cmp;
+mod encoding;
+mod from;
+mod mul;
+mod shl;
+mod shr;
+mod sub;
+
+#[cfg(feature = "rand_core")]
+mod rand;
+
+use crate::Zero;
+use core::fmt;
+use subtle::{Choice, ConditionallySelectable};
+
+#[cfg(feature = "serde")]
+use serdect::serde::{Deserialize, Deserializer, Serialize, Serializer};
+
+#[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
+compile_error!("this crate builds on 32-bit and 64-bit platforms only");
+
+//
+// 32-bit definitions
+//
+
+/// Inner integer type that the [`Limb`] newtype wraps.
+#[cfg(target_pointer_width = "32")]
+pub type Word = u32;
+
+/// Signed integer type that corresponds to [`Word`].
+#[cfg(target_pointer_width = "32")]
+pub(crate) type SignedWord = i32;
+
+/// Unsigned wide integer type: double the width of [`Word`].
+#[cfg(target_pointer_width = "32")]
+pub type WideWord = u64;
+
+/// Signed wide integer type: double the width of [`Limb`].
+#[cfg(target_pointer_width = "32")]
+pub(crate) type WideSignedWord = i64;
+
+//
+// 64-bit definitions
+//
+
+/// Unsigned integer type that the [`Limb`] newtype wraps.
+#[cfg(target_pointer_width = "64")]
+pub type Word = u64;
+
+/// Signed integer type that corresponds to [`Word`].
+#[cfg(target_pointer_width = "64")]
+pub(crate) type SignedWord = i64;
+
+/// Wide integer type: double the width of [`Word`].
+#[cfg(target_pointer_width = "64")]
+pub type WideWord = u128;
+
+/// Signed wide integer type: double the width of [`SignedWord`].
+#[cfg(target_pointer_width = "64")]
+pub(crate) type WideSignedWord = i128;
+
+//
+// Deprecated legacy names
+//
+
+// TODO(tarcieri): remove these in the next breaking release
+
+/// Deprecated: unsigned integer type that the [`Limb`] newtype wraps.
+#[deprecated(since = "0.4.8", note = "please use `Word` instead")]
+pub type LimbUInt = Word;
+
+/// Deprecated: wide integer type which is double the width of [`Word`].
+#[deprecated(since = "0.4.8", note = "please use `WideWord` instead")]
+pub type WideLimbUInt = WideWord;
+
+/// Highest bit in a [`Limb`].
+pub(crate) const HI_BIT: usize = Limb::BIT_SIZE - 1;
+
+/// Big integers are represented as an array of smaller CPU word-size integers
+/// called "limbs".
+#[derive(Copy, Clone, Debug, Default, Hash)]
+#[repr(transparent)]
+pub struct Limb(pub Word);
+
+impl Limb {
+ /// The value `0`.
+ pub const ZERO: Self = Limb(0);
+
+ /// The value `1`.
+ pub const ONE: Self = Limb(1);
+
+ /// Maximum value this [`Limb`] can express.
+ pub const MAX: Self = Limb(Word::MAX);
+
+ // 32-bit
+
+ /// Size of the inner integer in bits.
+ #[cfg(target_pointer_width = "32")]
+ pub const BIT_SIZE: usize = 32;
+ /// Size of the inner integer in bytes.
+ #[cfg(target_pointer_width = "32")]
+ pub const BYTE_SIZE: usize = 4;
+
+ // 64-bit
+
+ /// Size of the inner integer in bits.
+ #[cfg(target_pointer_width = "64")]
+ pub const BIT_SIZE: usize = 64;
+ /// Size of the inner integer in bytes.
+ #[cfg(target_pointer_width = "64")]
+ pub const BYTE_SIZE: usize = 8;
+
+ /// Return `a` if `c`==0 or `b` if `c`==`Word::MAX`.
+ ///
+ /// Const-friendly: we can't yet use `subtle` in `const fn` contexts.
+ #[inline]
+ pub(crate) const fn ct_select(a: Self, b: Self, c: Word) -> Self {
+ Self(a.0 ^ (c & (a.0 ^ b.0)))
+ }
+}
+
+impl ConditionallySelectable for Limb {
+ #[inline]
+ fn conditional_select(a: &Self, b: &Self, choice: Choice) -> Self {
+ Self(Word::conditional_select(&a.0, &b.0, choice))
+ }
+}
+
+impl Zero for Limb {
+ const ZERO: Self = Self::ZERO;
+}
+
+impl fmt::Display for Limb {
+ #[inline]
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ fmt::UpperHex::fmt(self, f)
+ }
+}
+
+impl fmt::LowerHex for Limb {
+ #[inline]
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ write!(f, "{:0width$x}", &self.0, width = Self::BYTE_SIZE * 2)
+ }
+}
+
+impl fmt::UpperHex for Limb {
+ #[inline]
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ write!(f, "{:0width$X}", &self.0, width = Self::BYTE_SIZE * 2)
+ }
+}
+
+#[cfg(feature = "serde")]
+#[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
+impl<'de> Deserialize<'de> for Limb {
+ fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+ where
+ D: Deserializer<'de>,
+ {
+ Ok(Self(Word::deserialize(deserializer)?))
+ }
+}
+
+#[cfg(feature = "serde")]
+#[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
+impl<'de> Serialize for Limb {
+ fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+ where
+ S: Serializer,
+ {
+ self.0.serialize(serializer)
+ }
+}
+
+#[cfg(feature = "zeroize")]
+#[cfg_attr(docsrs, doc(cfg(feature = "zeroize")))]
+impl zeroize::DefaultIsZeroes for Limb {}