func progedit(ctxt *obj.Link, p *obj.Prog, newprog obj.ProgAlloc) {

	// Expand binary instructions to ternary ones.
	if p.Reg == obj.REG_NONE {
		switch p.As {
		case AADDI, ASLTI, ASLTIU, AANDI, AORI, AXORI, ASLLI, ASRLI, ASRAI,
			AADDIW, ASLLIW, ASRLIW, ASRAIW, AADDW, ASUBW, ASLLW, ASRLW, ASRAW,
			AADD, AAND, AOR, AXOR, ASLL, ASRL, ASUB, ASRA,
			AMUL, AMULH, AMULHU, AMULHSU, AMULW, ADIV, ADIVU, ADIVW, ADIVUW,