diff --git a/test/asm/x86-64/X86_64AssemblerTestGen.v3 b/test/asm/x86-64/X86_64AssemblerTestGen.v3
index 24fef2664..9e80c035f 100644
--- a/test/asm/x86-64/X86_64AssemblerTestGen.v3
+++ b/test/asm/x86-64/X86_64AssemblerTestGen.v3
@@ -120,10 +120,11 @@ def main(a: Array<string>) -> int {
 
 	do_cmpxchng();
 	do_xchng();
-	do_xadd();
+	do_xaddn();
 	do_xorn();
 	do_orn();
 	do_andn();
+	do_negn();
 
 	do_r_dq("xchg", do_r_r, asm.d.xchg_r_r, asm.q.xchg_r_r);
 	do_m_dq("xchg", do_m_r, asm.d.xchg_m_r, asm.q.xchg_m_r);
@@ -354,7 +355,7 @@ def do_xchng() {
 	do_m_r("xchg qword", asm.xchgq_m_r);
 }
 
-def do_xadd() {
+def do_xaddn() {
 	regSize = 8;
 	do_m_r("xadd byte", asm.xaddb_m_r);
 	regSize = 16;
@@ -394,6 +395,17 @@ def do_andn() {
 	do_m_r("and qword", asm.andq_m_r);
 }
 
+def do_negn() {
+	regSize = 8;
+	do_m("and byte", asm.negb_m);
+	regSize = 16;
+	do_m("and word", asm.negw_m);
+	regSize = 32;
+	do_m("and dword", asm.negd_m);
+	regSize = 64;
+	do_m("and qword", asm.negq_m);
+}
+
 def do_set() {
 	var buf = StringBuilder.new();
 	for (cond in X86_64Conds.all) {