arnaucube/ark-r1cs-std
1
0
Fork 0
mirror of https://github.com/arnaucube/ark-r1cs-std.git synced 2026-01-09 07:21:29 +01:00
Code Issues Projects Releases Wiki Activity

CondSelectGadget for UInts

Browse Source
This commit is contained in:
Nirvan Tyagi
2020-11-19 22:32:21 -05:00
committed by Pratyush Mishra
parent edc9a8ce02
commit 0abb3a7dfe
2 changed files with 52 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
src/bits/uint.rs
View File

@@ -329,6 +329,31 @@ macro_rules! make_uint {
}
}
impl<ConstraintF: Field> CondSelectGadget<ConstraintF> for $name<ConstraintF> {
#[tracing::instrument(target = "r1cs")]
fn conditionally_select(
cond: &Boolean<ConstraintF>,
true_value: &Self,
false_value: &Self,
) -> Result<Self, SynthesisError> {
let selected_bits = true_value.bits.iter().zip(&false_value.bits)
.map(|(true_bit, false_bit)| {
cond.select(true_bit, false_bit)
}).collect::<Result<Vec<Boolean<ConstraintF>>, SynthesisError>>()?;
let selected_value = match (cond.value(), true_value.value(), false_value.value()) {
(Ok(true), Err(_), _) => None,
(Ok(true), Ok(v), _) => Some(v),
(Ok(false), _, Err(_)) => None,
(Ok(false), _, Ok(v)) => Some(v),
(Err(_), _, _) => None,
};
Ok(Self {
bits: selected_bits,
value: selected_value,
})
}
}
impl<ConstraintF: Field> AllocVar<$native, ConstraintF> for $name<ConstraintF> {
fn new_variable<T: Borrow<$native>>(
cs: impl Into<Namespace<ConstraintF>>,

27
src/bits/uint8.rs
View File

@@ -284,6 +284,33 @@ impl<ConstraintF: Field> EqGadget<ConstraintF> for UInt8<ConstraintF> {
}
}
impl<ConstraintF: Field> CondSelectGadget<ConstraintF> for UInt8<ConstraintF> {
#[tracing::instrument(target = "r1cs")]
fn conditionally_select(
cond: &Boolean<ConstraintF>,
true_value: &Self,
false_value: &Self,
) -> Result<Self, SynthesisError> {
let selected_bits = true_value
.bits
.iter()
.zip(&false_value.bits)
.map(|(true_bit, false_bit)| cond.select(true_bit, false_bit))
.collect::<Result<Vec<Boolean<ConstraintF>>, SynthesisError>>()?;
let selected_value = match (cond.value(), true_value.value(), false_value.value()) {
(Ok(true), Err(_), _) => None,
(Ok(true), Ok(v), _) => Some(v),
(Ok(false), _, Err(_)) => None,
(Ok(false), _, Ok(v)) => Some(v),
(Err(_), _, _) => None,
};
Ok(Self {
bits: selected_bits,
value: selected_value,
})
}
}
impl<ConstraintF: Field> AllocVar<u8, ConstraintF> for UInt8<ConstraintF> {
fn new_variable<T: Borrow<u8>>(
cs: impl Into<Namespace<ConstraintF>>,