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use snarkvm_fields::PrimeField;
use snarkvm_r1cs::ConstraintSystem;
use crate::{
bits::Boolean,
errors::SignedIntegerError,
integers::int::*,
traits::{
alloc::AllocGadget,
integers::{Integer, Mul, Pow},
select::CondSelectGadget,
},
};
macro_rules! pow_int_impl {
($($gadget:ty)*) => ($(
impl<F: PrimeField> Pow<F> for $gadget {
type ErrorType = SignedIntegerError;
fn pow<CS: ConstraintSystem<F>>(&self, mut cs: CS, other: &Self) -> Result<Self, Self::ErrorType> {
let is_constant = Boolean::constant(Self::result_is_constant(&self, &other));
let one_const = Self::constant(1 as <$gadget as Integer>::IntegerType);
let one_alloc = Self::alloc(&mut cs.ns(|| "allocated_1"), || Ok(1 as <$gadget as Integer>::IntegerType))?;
let mut result = Self::conditionally_select(
&mut cs.ns(|| "constant_or_allocated"),
&is_constant,
&one_const,
&one_alloc,
)?;
for (i, bit) in other.bits.iter().rev().enumerate() {
result = result.mul(cs.ns(|| format!("square_{}", i)), &result)?;
let mul_by_self = result
.mul_unsafe(cs.ns(|| format!("multiply_by_self_{}", i)), &self);
result = Self::conditionally_select(
&mut cs.ns(|| format!("mul_by_self_or_result_{}", i)),
bit,
&mul_by_self?,
&result,
)?;
}
Ok(result)
}
}
)*)
}
pow_int_impl!(Int8 Int16 Int32 Int64 Int128);