wip

math/src/modulus.rs

@@ -0,0 +1,125 @@
+pub mod prime;
+pub mod barrett;
+pub mod montgomery;
+pub mod impl_u64;
+
+pub type REDUCEMOD = u8;
+
+pub const NONE: REDUCEMOD = 0;
+pub const ONCE: REDUCEMOD = 1;
+pub const TWICE: REDUCEMOD = 2;
+pub const FOURTIMES: REDUCEMOD = 3;
+pub const BARRETT: REDUCEMOD = 4;
+pub const BARRETTLAZY: REDUCEMOD = 5;
+
+pub trait WordOps<O>{
+    fn log2(self) -> O;
+    fn reverse_bits_msb(self, n:u32) -> O;
+}
+
+impl WordOps<u64> for u64{
+    #[inline(always)]
+    fn log2(self) -> u64{
+        (u64::BITS - (self-1).leading_zeros()) as _
+    }
+    #[inline(always)]
+    fn reverse_bits_msb(self, n: u32) -> u64{
+        self.reverse_bits() >> (usize::BITS - n)
+    }
+}
+
+impl WordOps<usize> for usize{
+    #[inline(always)]
+    fn log2(self) -> usize{
+        (usize::BITS - (self-1).leading_zeros()) as _
+    }
+    #[inline(always)]
+    fn reverse_bits_msb(self, n: u32) -> usize{
+        self.reverse_bits() >> (usize::BITS - n)
+    }
+}
+
+pub trait ReduceOnce<O>{
+    /// Assigns self-q to self if self >= q in constant time.
+    /// User must ensure that 2q fits in O.
+    fn reduce_once_constant_time_assign(&mut self, q: O);
+    /// Returns self-q if self >= q else self in constant time.
+    /// /// User must ensure that 2q fits in O.
+    fn reduce_once_constant_time(&self, q:O) -> O;
+    /// Assigns self-q to self if self >= q.
+    /// /// User must ensure that 2q fits in O.
+    fn reduce_once_assign(&mut self, q: O);
+    /// Returns self-q if self >= q else self.
+    /// /// User must ensure that 2q fits in O.
+    fn reduce_once(&self, q:O) -> O;
+}
+
+pub trait WordOperations<O>{
+
+    // Applies a parameterized modular reduction.
+    fn word_reduce_assign<const REDUCE:REDUCEMOD>(&self, x: &mut O);
+
+    // Assigns a + b to c.
+    fn word_add_binary_assign<const REDUCE:REDUCEMOD>(&self, a: &O, b:&O, c: &mut O);
+
+    // Assigns a + b to b.
+    fn word_add_unary_assign<const REDUCE:REDUCEMOD>(&self, a: &O, b: &mut O);
+
+    // Assigns a - b to c.
+    fn word_sub_binary_assign<const REDUCE:REDUCEMOD>(&self, a: &O, b:&O, c: &mut O);
+
+    // Assigns b - a to b.
+    fn word_sub_unary_assign<const REDUCE:REDUCEMOD>(&self, a: &O, b: &mut O);
+
+    // Assigns -a to a.
+    fn word_neg_unary_assign<const REDUCE:REDUCEMOD>(&self, a:&mut O);
+
+    // Assigns -a to b.
+    fn word_neg_binary_assign<const REDUCE:REDUCEMOD>(&self, a: &O, b:&mut O);
+
+    // Assigns a * 2^64 to b.
+    fn word_prepare_montgomery_assign<const REDUCE:REDUCEMOD>(&self, a: &O, b: &mut montgomery::Montgomery<O>);
+
+    // Assigns a * b to c.
+    fn word_mul_montgomery_external_binary_assign<const REDUCE:REDUCEMOD>(&self, a:&montgomery::Montgomery<O>, b:&O, c: &mut O);
+
+    // Assigns a * b to b.
+    fn word_mul_montgomery_external_unary_assign<const REDUCE:REDUCEMOD>(&self, a:&montgomery::Montgomery<O>, b:&mut O);
+}
+
+pub trait VecOperations<O>{
+
+    // Applies a parameterized modular reduction.
+    fn vec_reduce_assign<const CHUNK:usize, const REDUCE:REDUCEMOD>(&self, x: &mut [O]);
+
+    // Assigns a[i] + b[i] to c[i]
+    fn vec_add_binary_assign<const CHUNK:usize, const REDUCE:REDUCEMOD>(&self, a: &[O], b:&[O], c: &mut [O]);
+
+    // Assigns a[i] + b[i] to b[i]
+    fn vec_add_unary_assign<const CHUNK:usize, const REDUCE:REDUCEMOD>(&self, a: &[O], b: &mut [O]);
+
+    // Assigns a[i] - b[i] to c[i]
+    fn vec_sub_binary_assign<const CHUNK:usize, const REDUCE:REDUCEMOD>(&self, a: &[O], b:&[O], c: &mut [O]);
+
+    // Assigns a[i] - b[i] to b[i]
+    fn vec_sub_unary_assign<const CHUNK:usize, const REDUCE:REDUCEMOD>(&self, a: &[O], b: &mut [O]);
+
+    // Assigns -a[i] to a[i].
+    fn vec_neg_unary_assign<const CHUNK:usize, const REDUCE:REDUCEMOD>(&self, a: &mut [O]);
+
+    // Assigns -a[i] to a[i].
+    fn vec_neg_binary_assign<const CHUNK:usize, const REDUCE:REDUCEMOD>(&self, a: &[O], b: &mut [O]);
+
+    // Assigns a * 2^64 to b.
+    fn vec_prepare_montgomery_assign<const CHUNK:usize, const REDUCE:REDUCEMOD>(&self, a: &[O], b: &mut [montgomery::Montgomery<O>]);
+
+    // Assigns a[i] * b[i] to c[i].
+    fn vec_mul_montgomery_external_binary_assign<const CHUNK:usize,const REDUCE:REDUCEMOD>(&self, a:&[montgomery::Montgomery<O>], b:&[O], c: &mut [O]);
+
+    // Assigns a[i] * b[i] to b[i].
+    fn vec_mul_montgomery_external_unary_assign<const CHUNK:usize, const REDUCE:REDUCEMOD>(&self, a:&[montgomery::Montgomery<O>], b:&mut [O]);
+}
+
+
+
+