From 7c121886504f99ded758050568deca1742cf000d Mon Sep 17 00:00:00 2001
From: Evgenii <evgeniy@nspcc.ru>
Date: Fri, 19 Jul 2019 19:04:44 +0300
Subject: [PATCH] Perform allocation outside of mulBitRightPure

---
 tz/pure.go | 40 ++++++++++++++++++++--------------------
 1 file changed, 20 insertions(+), 20 deletions(-)

diff --git a/tz/pure.go b/tz/pure.go
index 44989e3..d1a5961 100644
--- a/tz/pure.go
+++ b/tz/pure.go
@@ -43,15 +43,16 @@ func (d *digestp) Reset() {
 
 func (d *digestp) Write(data []byte) (n int, err error) {
 	n = len(data)
+	tmp := new(gogf127.GF127)
 	for _, b := range data {
-		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x80 != 0)
-		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x40 != 0)
-		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x20 != 0)
-		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x10 != 0)
-		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x08 != 0)
-		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x04 != 0)
-		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x02 != 0)
-		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x01 != 0)
+		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x80 != 0, tmp)
+		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x40 != 0, tmp)
+		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x20 != 0, tmp)
+		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x10 != 0, tmp)
+		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x08 != 0, tmp)
+		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x04 != 0, tmp)
+		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x02 != 0, tmp)
+		mulBitRightPure(&d.x[0], &d.x[1], &d.x[2], &d.x[3], b&0x01 != 0, tmp)
 	}
 	return
 }
@@ -64,29 +65,28 @@ func (d *digestp) BlockSize() int {
 	return hashBlockSize
 }
 
-func mulBitRightPure(c00, c01, c10, c11 *gogf127.GF127, bit bool) {
-	var tmp gogf127.GF127
+func mulBitRightPure(c00, c01, c10, c11 *gogf127.GF127, bit bool, tmp *gogf127.GF127) {
 	if bit {
-		tmp = *c00
+		*tmp = *c00
 		gogf127.Mul10(c00, c00)
 		gogf127.Add(c00, c01, c00)
-		gogf127.Mul11(&tmp, &tmp)
-		gogf127.Add(c01, &tmp, c01)
+		gogf127.Mul11(tmp, tmp)
+		gogf127.Add(c01, tmp, c01)
 
-		tmp = *c10
+		*tmp = *c10
 		gogf127.Mul10(c10, c10)
 		gogf127.Add(c10, c11, c10)
-		gogf127.Mul11(&tmp, &tmp)
-		gogf127.Add(c11, &tmp, c11)
+		gogf127.Mul11(tmp, tmp)
+		gogf127.Add(c11, tmp, c11)
 	} else {
-		tmp = *c00
+		*tmp = *c00
 		gogf127.Mul10(c00, c00)
 		gogf127.Add(c00, c01, c00)
-		*c01 = tmp
+		*c01 = *tmp
 
-		tmp = *c10
+		*tmp = *c10
 		gogf127.Mul10(c10, c10)
 		gogf127.Add(c10, c11, c10)
-		*c11 = tmp
+		*c11 = *tmp
 	}
 }