From afff1ce6745c40d6d3534d0ff701924566160e11 Mon Sep 17 00:00:00 2001
From: Constance <constance@qed-it.com>
Date: Mon, 18 Dec 2023 09:55:20 +0100
Subject: [PATCH] Update comments

---
 halo2_gadgets/src/utilities/cond_swap.rs | 29 ++++++++++--------------
 1 file changed, 12 insertions(+), 17 deletions(-)

diff --git a/halo2_gadgets/src/utilities/cond_swap.rs b/halo2_gadgets/src/utilities/cond_swap.rs
index 062314425..dbb2a4558 100644
--- a/halo2_gadgets/src/utilities/cond_swap.rs
+++ b/halo2_gadgets/src/utilities/cond_swap.rs
@@ -27,9 +27,8 @@ pub trait CondSwapInstructions<F: Field>: UtilitiesInstructions<F> {
         swap: Value<bool>,
     ) -> Result<(Self::Var, Self::Var), Error>;
 
-    /// Given an input `(choice, left, right)`, returns `left` if choice=0 and `right` otherwise.
-    ///
-    /// `choice` must be constrained to {0, 1} separately.
+    /// Given an input `(choice, left, right)` where `choice` is a boolean flag,
+    /// returns `left` if `choice` is not set and `right` if `choice` is set.
     fn mux(
         &self,
         layouter: &mut impl Layouter<F>,
@@ -164,10 +163,10 @@ impl<F: PrimeField> CondSwapInstructions<F> for CondSwapChip<F> {
                     .zip(right.value())
                     .zip(choice.value())
                     .map(|((left, right), choice)| {
-                        if *choice == F::from(1_u64) {
-                            right
-                        } else {
+                        if *choice == F::from(0_u64) {
                             left
+                        } else {
+                            right
                         }
                     })
                     .cloned();
@@ -176,10 +175,10 @@ impl<F: PrimeField> CondSwapInstructions<F> for CondSwapChip<F> {
                     .zip(right.value())
                     .zip(choice.value())
                     .map(|((left, right), choice)| {
-                        if *choice == F::from(1_u64) {
-                            left
-                        } else {
+                        if *choice == F::from(0_u64) {
                             right
+                        } else {
+                            left
                         }
                     })
                     .cloned();
@@ -192,10 +191,8 @@ impl<F: PrimeField> CondSwapInstructions<F> for CondSwapChip<F> {
 }
 
 impl CondSwapChip<pallas::Base> {
-    /// Given an input `(choice, left, right)`, returns `left` if choice=0 and `right` otherwise.
-    ///
-    /// `left` and `right` are `EccPoint`
-    /// `choice` must be constrained to {0, 1} separately.
+    /// Given an input `(choice, left, right)` where `choice` is a boolean flag and `left` and `right` are `EccPoint`,
+    /// returns `left` if `choice` is not set and `right` if `choice` is set.
     pub fn mux_on_points(
         &self,
         mut layouter: impl Layouter<pallas::Base>,
@@ -211,10 +208,8 @@ impl CondSwapChip<pallas::Base> {
         ))
     }
 
-    /// Given an input `(choice, left, right)`, returns `left` if choice=0 and `right` otherwise.
-    ///
-    /// `left` and `right` are `NonIdentityEccPoint`
-    /// `choice` must be constrained to {0, 1} separately.
+    /// Given an input `(choice, left, right)` where `choice` is a boolean flag and `left` and `right` are
+    /// `NonIdentityEccPoint`, returns `left` if `choice` is not set and `right` if `choice` is set.
     pub fn mux_on_non_identity_points(
         &self,
         mut layouter: impl Layouter<pallas::Base>,