ctxt.Diag("invalid encoding for argument %v", p)
}

func linkpatch(ctxt *Link, sym *LSym, newprog ProgAlloc) {
	for p := sym.Func().Text; p != nil; p = p.Link {
		checkaddr(ctxt, p, &p.From)
		for _, v := range p.RestArgs {
			checkaddr(ctxt, p, &v.Addr)
		}
		checkaddr(ctxt, p, &p.To)

		if ctxt.Arch.Progedit != nil {
			ctxt.Arch.Progedit(ctxt, p, newprog)
		}
		if p.To.Type != TYPE_BRANCH {
			continue
		}

		p1.From.Sym = ctxt.Lookup("_GLOBAL_OFFSET_TABLE_")
		p1.To.Type = obj.TYPE_REG
		p1.To.Reg = REG_BX

		p2.As = p.As
		p2.Scond = p.Scond
		p2.From = p.From
		if p.RestArgs != nil {
			p2.RestArgs = append(p2.RestArgs, p.RestArgs...)
		}
		p2.Reg = p.Reg
		p2.To = p.To
		// p.To.Type was set to TYPE_BRANCH above, but that makes checkaddr
		// in ../pass.go complain, so set it back to TYPE_MEM here, until p2

		return &optab[p.Optab-1]
	}
	if len(p.RestArgs) > 3 {
		c.ctxt.Diag("too many RestArgs: got %v, maximum is 3\n", len(p.RestArgs))
		return nil
	}

	// Initialize classes for all arguments.
	p.From.Class = int8(c.aclass(&p.From) + 1)
	p.To.Class = int8(c.aclass(&p.To) + 1)
	for i := range p.RestArgs {
		p.RestArgs[i].Addr.Class = int8(c.aclass(&p.RestArgs[i].Addr) + 1)
	}

					return
				}
				// For ARM64 CASP-like instructions, its 2nd destination operand is register pair(Rt, Rt+1) that can
				// not fit into prog.RegTo2, so save it to the prog.RestArgs.
				prog.AddRestDest(a[2])
			default:
				prog.From = a[0]
				prog.Reg = p.getRegister(prog, op, &a[1])
				prog.To = a[2]
			}
		case sys.I386:
			prog.From = a[0]
			prog.AddRestSource(a[1])

type Optab struct {
	as    obj.As // Opcode
	a1    uint8  // p.From argument (obj.Addr). p is of type obj.Prog.
	a2    uint8  // p.Reg argument (int16 Register)
	a3    uint8  // p.RestArgs[0]  (obj.AddrPos)
	a4    uint8  // p.RestArgs[1]
	a5    uint8  // p.RestARgs[2]
	a6    uint8  // p.To (obj.Addr)
	type_ int8   // cases in asmout below. E.g., 44 = st r,(ra+rb); 45 = ld (ra+rb), r
	size  int8   // Text space in bytes to lay operation

	}

	// 2nd destination operand
	a5 := C_NONE
	if p.RegTo2 != 0 {
		a5 = C_REG
	}

	// 3rd source operand
	a3 := C_NONE
	if len(p.RestArgs) > 0 {
		a3 = int(p.RestArgs[0].Class)
		if a3 == 0 {
			a3 = c.aclass(&p.RestArgs[0].Addr) + 1
			p.RestArgs[0].Class = int8(a3)
		}
		a3--
	}

	ops := oprange[p.As&obj.AMask]
	c1 := &xcmp[a1]
	c4 := &xcmp[a4]
	for i := range ops {

	ins := &instruction{
		as:  p.As,
		rd:  uint32(p.To.Reg),
		rs1: uint32(p.Reg),
		rs2: uint32(p.From.Reg),
		imm: p.From.Offset,
	}
	if len(p.RestArgs) == 1 {
		ins.rs3 = uint32(p.RestArgs[0].Reg)
	}
	return ins
}

// instructionsForOpImmediate returns the machine instructions for an immediate
// operand. The instruction is specified by as and the source register is

func unpackOps4(p *obj.Prog) (arg0, arg1, arg2, dst *obj.Addr) {
	return &p.From, &p.RestArgs[0].Addr, &p.RestArgs[1].Addr, &p.To
}

// unpackOps5 extracts 5 operands from p.
func unpackOps5(p *obj.Prog) (arg0, arg1, arg2, arg3, dst *obj.Addr) {
	return &p.From, &p.RestArgs[0].Addr, &p.RestArgs[1].Addr, &p.RestArgs[2].Addr, &p.To

	case AVMOVQ:
		if p.From.Type == obj.TYPE_CONST {
			p.From.Type = obj.TYPE_MEM
			p.From.Sym = c.ctxt.Int128Sym(p.GetFrom3().Offset, p.From.Offset)
			p.From.Name = obj.NAME_EXTERN
			p.From.Offset = 0
			p.RestArgs = nil
		}

	case AFMOVS:
		if p.From.Type == obj.TYPE_FCONST {
			f64 := p.From.Val.(float64)
			f32 := float32(f64)
			if c.chipfloat7(f64) > 0 {
				break
			}

const (
	REGFROM = 1
)

type Optab struct {
	as    obj.As
	a1    uint8 // Prog.From
	a2    uint8 // 2nd source operand, Prog.Reg or Prog.RestArgs[XXX]
	a3    uint8 // 3rd source operand, Prog.RestArgs[XXX]
	a4    uint8 // Prog.To
	a5    uint8 // 2nd destination operand, Prog.RegTo2 or Prog.RestArgs[XXX]
	type_ int8
	size_ int8 // the value of this field is not static, use the size() method to return the value
	param int16
	flag  int8