diff --git a/src/arch/i386.ins b/src/arch/i386.ins
index ad6557d..1839c6a 100644
--- a/src/arch/i386.ins
+++ b/src/arch/i386.ins
@@ -65,6 +65,14 @@
 #define OP_ebp		AO_REGISTER(AOF_IMPLICIT, 32, REG_ebp_id)
 #define OP_esi		AO_REGISTER(AOF_IMPLICIT, 32, REG_esi_id)
 #define OP_edi		AO_REGISTER(AOF_IMPLICIT, 32, REG_edi_id)
+#define OP_st0		AO_REGISTER(AOF_IMPLICIT, 32, REG_st0_id)
+#define OP_st1		AO_REGISTER(AOF_IMPLICIT, 32, REG_st1_id)
+#define OP_st2		AO_REGISTER(AOF_IMPLICIT, 32, REG_st2_id)
+#define OP_st3		AO_REGISTER(AOF_IMPLICIT, 32, REG_st3_id)
+#define OP_st4		AO_REGISTER(AOF_IMPLICIT, 32, REG_st4_id)
+#define OP_st5		AO_REGISTER(AOF_IMPLICIT, 32, REG_st5_id)
+#define OP_st6		AO_REGISTER(AOF_IMPLICIT, 32, REG_st6_id)
+#define OP_st7		AO_REGISTER(AOF_IMPLICIT, 32, REG_st7_id)
 
 /* mod r/m byte */
 #define AOF_I386_MODRM	0x2
@@ -358,5 +366,42 @@
 { "f2xm1",	0xd9f0,		OP2F, AOT_NONE,   AOT_NONE,  AOT_NONE	},
 /* FABS		0xd9e1		2					*/
 { "fabs",	0xd9e1,		OP2F, AOT_NONE,   AOT_NONE,  AOT_NONE	},
+/* FADD		0xd8 /0		1     m32real				*/
+/* FIXME implement */
+/* FADD		0xdc /0		1     m64real				*/
+/* FIXME implement */
+/* FADD		0xd8c0 +i	2     st(0)       st(i)			*/
+{ "fadd",	0xd8c0,		OP2F, OP_st0,     OP_st0,    AOT_NONE	},
+{ "fadd",	0xd8c1,		OP2F, OP_st0,     OP_st1,    AOT_NONE	},
+{ "fadd",	0xd8c2,		OP2F, OP_st0,     OP_st2,    AOT_NONE	},
+{ "fadd",	0xd8c3,		OP2F, OP_st0,     OP_st3,    AOT_NONE	},
+{ "fadd",	0xd8c4,		OP2F, OP_st0,     OP_st4,    AOT_NONE	},
+{ "fadd",	0xd8c5,		OP2F, OP_st0,     OP_st5,    AOT_NONE	},
+{ "fadd",	0xd8c6,		OP2F, OP_st0,     OP_st6,    AOT_NONE	},
+{ "fadd",	0xd8c7,		OP2F, OP_st0,     OP_st7,    AOT_NONE	},
+/* FADD		0xdcc0 +i	2     st(i)       st(0)			*/
+{ "fadd",	0xdcc0,		OP2F, OP_st0,     OP_st0,    AOT_NONE	},
+{ "fadd",	0xdcc1,		OP2F, OP_st1,     OP_st0,    AOT_NONE	},
+{ "fadd",	0xdcc2,		OP2F, OP_st2,     OP_st0,    AOT_NONE	},
+{ "fadd",	0xdcc3,		OP2F, OP_st3,     OP_st0,    AOT_NONE	},
+{ "fadd",	0xdcc4,		OP2F, OP_st4,     OP_st0,    AOT_NONE	},
+{ "fadd",	0xdcc5,		OP2F, OP_st5,     OP_st0,    AOT_NONE	},
+{ "fadd",	0xdcc6,		OP2F, OP_st6,     OP_st0,    AOT_NONE	},
+{ "fadd",	0xdcc7,		OP2F, OP_st7,     OP_st0,    AOT_NONE	},
+/* FADDP	0xdec1		2					*/
+{ "faddp",	0xdec1,		OP2F, AOT_NONE,   AOT_NONE,  AOT_NONE	},
+/* FADDP	0xdec0 +i	2     st(i)       st(0)			*/
+{ "faddp",	0xdec0,		OP2F, OP_st0,     OP_st0,    AOT_NONE	},
+{ "faddp",	0xdec1,		OP2F, OP_st1,     OP_st0,    AOT_NONE	},
+{ "faddp",	0xdec2,		OP2F, OP_st2,     OP_st0,    AOT_NONE	},
+{ "faddp",	0xdec3,		OP2F, OP_st3,     OP_st0,    AOT_NONE	},
+{ "faddp",	0xdec4,		OP2F, OP_st4,     OP_st0,    AOT_NONE	},
+{ "faddp",	0xdec5,		OP2F, OP_st5,     OP_st0,    AOT_NONE	},
+{ "faddp",	0xdec6,		OP2F, OP_st6,     OP_st0,    AOT_NONE	},
+{ "faddp",	0xdec7,		OP2F, OP_st7,     OP_st0,    AOT_NONE	},
+/* FIADD	0xda /0		1     m32int				*/
+/* FIXME implement */
+/* FIADD	0xde /0		1     m64int				*/
+/* FIXME implement */
 /* NOP		0x90		1					*/
 { "nop",	0x90,		OP1F, AOT_NONE,   AOT_NONE,  AOT_NONE	},
diff --git a/test/i386.S b/test/i386.S
index aef6c34..f0369ad 100644
--- a/test/i386.S
+++ b/test/i386.S
@@ -116,4 +116,29 @@
 	enter	$0xfacd, $0x42			/* c8 cd fa 42		*/
 	f2xm1
 	fabs
+	/* FADD */
+	fadd	%st0, %st0
+	fadd	%st0, %st1
+	fadd	%st0, %st2
+	fadd	%st0, %st3
+	fadd	%st0, %st4
+	fadd	%st0, %st5
+	fadd	%st0, %st6
+	fadd	%st0, %st7
+	fadd	%st1, %st0
+	fadd	%st2, %st0
+	fadd	%st3, %st0
+	fadd	%st4, %st0
+	fadd	%st5, %st0
+	fadd	%st6, %st0
+	fadd	%st7, %st0
+	/* FADDP */
+	faddp	%st0, %st0
+	faddp
+	faddp	%st2, %st0
+	faddp	%st3, %st0
+	faddp	%st4, %st0
+	faddp	%st5, %st0
+	faddp	%st6, %st0
+	faddp	%st7, %st0
 	nop					/* 0x90			*/