diff --git a/arch/X86/X86Mapping.c b/arch/X86/X86Mapping.c
index 455c0100c4..26906ec7b9 100644
--- a/arch/X86/X86Mapping.c
+++ b/arch/X86/X86Mapping.c
@@ -1622,7 +1622,6 @@ static bool valid_repne(cs_struct *h, unsigned int opcode)
 			case X86_INS_MOVSB:
 			case X86_INS_MOVSS:
 			case X86_INS_MOVSW:
-			case X86_INS_MOVSD:
 			case X86_INS_MOVSQ:
 
 			case X86_INS_LODSB:
@@ -1645,6 +1644,11 @@ static bool valid_repne(cs_struct *h, unsigned int opcode)
 
 				return true;
 
+			case X86_INS_MOVSD:
+				if (opcode == X86_MOVSW) // REP MOVSB
+					return true;
+				return false;
+
 			case X86_INS_CMPSD:
 				if (opcode == X86_CMPSL) // REP CMPSD
 					return true;