ac: LODS/B AL,Xb
ad: LODS/W/D/Q rAX,Xv
ae: SCAS/B AL,Yb
-af: SCAS/W/D/Q rAX,Xv
+# Note: The May 2011 Intel manual shows Xv for the second parameter of the
+# next instruction but Yv is correct
+af: SCAS/W/D/Q rAX,Yv
# 0xb0 - 0xbf
b0: MOV AL/R8L,Ib
b1: MOV CL/R9L,Ib