diff --git a/insns.dat b/insns.dat
index 5404ce07..437ffbc2 100644
--- a/insns.dat
+++ b/insns.dat
@@ -587,7 +587,7 @@ IMUL		reg16,reg16,sbyte16		\320\1\x6B\110\16				186,SM,ND
 IMUL		reg16,reg16,imm16		\320\1\x69\110\32				186
 IMUL		reg16,reg16,imm			\320\146\x69\110\142				186,SM,ND
 IMUL		reg32,mem,imm8			\321\1\x6B\110\16				386,SM
-IMUL		reg32,mem,sbyte64		\321\1\x6B\110\16				386,SM,ND
+IMUL		reg32,mem,sbyte32		\321\1\x6B\110\16				386,SM,ND
 IMUL		reg32,mem,imm32			\321\1\x69\110\42				386,SM
 IMUL		reg32,mem,imm			\321\156\x69\110\152				386,SM,ND
 IMUL		reg32,reg32,imm8		\321\1\x6B\110\16				386