From: John Hodge (sonata) <tpg@mutabah.net>
Date: Mon, 3 Nov 2014 10:21:53 +0000 (+0800)
Subject: Kernel/x86_64 - Fix broken memset
X-Git-Url: https://git.ucc.asn.au/?a=commitdiff_plain;h=5840e1515195ccea72f945b03239b79dcf220c16;p=tpg%2Facess2.git

Kernel/x86_64 - Fix broken memset
---

diff --git a/KernelLand/Kernel/arch/x86_64/lib.c b/KernelLand/Kernel/arch/x86_64/lib.c
index 977cffd1..85dda824 100644
--- a/KernelLand/Kernel/arch/x86_64/lib.c
+++ b/KernelLand/Kernel/arch/x86_64/lib.c
@@ -370,11 +370,11 @@ void *memset(void *__dest, int __val, size_t __count)
 		__asm__ __volatile__ ("rep stosb" : : "D"(__dest),"a"(__val),"c"(__count));
 	else {
 		Uint8   *dst = __dest;
+		size_t	qwords = __count / 8;
+		size_t	trail_bytes = __count % 8;
 
-		__asm__ __volatile__ ("rep stosq" : : "D"(dst),"a"(0),"c"(__count/8));
-		dst += __count & ~7;
-		__count = __count & 7;
-		while( __count-- )
+		__asm__ __volatile__ ("rep stosq" : "=D"(dst) : "D"(dst),"a"(0),"c"(qwords));
+		while( trail_bytes-- )
 		        *dst++ = 0;
 	}
 	return __dest;