From 43ff72405cae657665a5a017aaf36d0782f2a186 Mon Sep 17 00:00:00 2001
From: Ruben Vermeersch <ruben@rocketeer.be>
Date: Fri, 24 Jan 2020 16:45:29 +0100
Subject: [PATCH] Add bounds checks to loops

---
 xor.go       |  5 +++++
 xor_amd64.go | 10 ++++++++++
 2 files changed, 15 insertions(+)

diff --git a/xor.go b/xor.go
index 791b171..680d425 100644
--- a/xor.go
+++ b/xor.go
@@ -12,6 +12,9 @@ func Bytes(dst, a, b []byte) int {
 	if len(dst) < n {
 		n = len(dst)
 	}
+	_ = dst[n-1]
+	_ = a[n-1]
+	_ = b[n-1]
 	for i := 0; i < n; i++ {
 		dst[i] = a[i] ^ b[i]
 	}
@@ -26,6 +29,8 @@ func Byte(dst, a []byte, b byte) int {
 	if len(dst) < n {
 		n = len(dst)
 	}
+	_ = dst[n-1]
+	_ = a[n-1]
 	for i := 0; i < n; i++ {
 		dst[i] = a[i] ^ b
 	}
diff --git a/xor_amd64.go b/xor_amd64.go
index cb2ed16..a90a5d2 100644
--- a/xor_amd64.go
+++ b/xor_amd64.go
@@ -53,11 +53,17 @@ func xorBytesGeneric(dst, a, b []byte, n int) {
 		dw := *(*[]uintptr)(unsafe.Pointer(&dst))
 		aw := *(*[]uintptr)(unsafe.Pointer(&a))
 		bw := *(*[]uintptr)(unsafe.Pointer(&b))
+		_ = aw[w-1]
+		_ = bw[w-1]
+		_ = dw[w-1]
 		for i := 0; i < w; i++ {
 			dw[i] = aw[i] ^ bw[i]
 		}
 	}
 
+	_ = dst[n-1]
+	_ = a[n-1]
+	_ = b[n-1]
 	for i := (n - n%wordSize); i < n; i++ {
 		dst[i] = a[i] ^ b[i]
 	}
@@ -81,11 +87,15 @@ func Byte(dst, a []byte, b byte) int {
 	if w > 0 {
 		dw := *(*[]uintptr)(unsafe.Pointer(&dst))
 		aw := *(*[]uintptr)(unsafe.Pointer(&a))
+		_ = aw[w-1]
+		_ = dw[w-1]
 		for i := 0; i < w; i++ {
 			dw[i] = aw[i] ^ bw
 		}
 	}
 
+	_ = dst[n-1]
+	_ = a[n-1]
 	for i := (n - n%wordSize); i < n; i++ {
 		dst[i] = a[i] ^ b
 	}