From 8059980336713870d49f37a4e26f846f9a878770 Mon Sep 17 00:00:00 2001
From: Henry de Valence <hdevalence@hdevalence.ca>
Date: Wed, 8 May 2019 21:18:02 -0700
Subject: [PATCH] internal/scalar: use one scMulAdd for Sub

---
 internal/scalar/scalar.go | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/internal/scalar/scalar.go b/internal/scalar/scalar.go
index e285949..d705388 100644
--- a/internal/scalar/scalar.go
+++ b/internal/scalar/scalar.go
@@ -28,12 +28,8 @@ func (s *Scalar) Add(x, y *Scalar) *Scalar {
 
 // Sub sets s = x - y mod l and returns s.
 func (s *Scalar) Sub(x, y *Scalar) *Scalar {
-	// tmp = -1 * y + 0
-	var tmp Scalar
-	scMulAdd(&tmp, &scMinusOne, y, &scZero)
-
-	// s = 1 * x - y
-	scMulAdd(s, &scOne, x, &tmp)
+	// s = -1 * y + x
+	scMulAdd(s, &scMinusOne, y, x)
 	return s
 }