From: Martin Willi <martin@revosec.ch>
Date: Thu, 19 Mar 2015 15:29:42 +0000 (+0100)
Subject: utils: Make use of 128-bit integer support in memxor()
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=63da7db13eae8e9c42972e21f9520a66c405d719;p=thirdparty%2Fstrongswan.git

utils: Make use of 128-bit integer support in memxor()

If inlined, this can improve memxor() performance significantly. This increases
AES-GCM performance by ~20% when building with an instruction set supporting
such words natively.
---

diff --git a/src/libstrongswan/utils/utils.h b/src/libstrongswan/utils/utils.h
index 8ee94ab091..e1dedc356e 100644
--- a/src/libstrongswan/utils/utils.h
+++ b/src/libstrongswan/utils/utils.h
@@ -564,14 +564,22 @@ static inline void memxor_inline(u_int8_t dst[], u_int8_t src[], size_t n)
 	int m, i;
 
 	/* byte wise XOR until dst aligned */
-	for (i = 0; (uintptr_t)&dst[i] % sizeof(long) && i < n; i++)
+	for (i = 0; (uintptr_t)&dst[i] % sizeof(MAX_INT_TYPE) && i < n; i++)
 	{
 		dst[i] ^= src[i];
 	}
 	/* try to use words if src shares an aligment with dst */
-	switch (((uintptr_t)&src[i] % sizeof(long)))
+	switch (((uintptr_t)&src[i] % sizeof(MAX_INT_TYPE)))
 	{
+#ifdef HAVE_INT128
 		case 0:
+			for (m = n - sizeof(int128_t); i <= m; i += sizeof(int128_t))
+			{
+				*(int128_t*)&dst[i] ^= *(int128_t*)&src[i];
+			}
+			break;
+#endif
+		case sizeof(MAX_INT_TYPE) - sizeof(long):
 			for (m = n - sizeof(long); i <= m; i += sizeof(long))
 			{
 				*(long*)&dst[i] ^= *(long*)&src[i];