sem [ casa casxa ] {
    val aa = Rx(rs1); val xx = ms(aa);
    if(rsrc(rs2)?ext(64) == xx) md(aa,rsrc(rd)); rdest(rd,xx);
} where rsrc in [R4 Rx], rdest in [R4 Rx],
	ms in [M4 M8], md in [M4 M8];