r = rt
		}
		if rt == REGSP || r == REGSP {
			o2 = c.opxrrr(p, p.As, rt, r, rf, false)
			o2 |= uint32(lsl0)
		} else {
			o2 = c.oprrr(p, p.As)
			o2 |= uint32(rf&31) << 16 /* shift is 0 */
			o2 |= uint32(r&31) << 5
			o2 |= uint32(rt & 31)
		}

	case 63: /* op Vm.<t>, Vn.<T>, Vd.<T> */
		o1 |= c.oprrr(p, p.As)
		af := (p.From.Reg >> 5) & 15
		at := (p.To.Reg >> 5) & 15

		switch o.size {
		case 12:
			o1 = OP_IRR(c.opirr(ALUI), uint32((v+1<<15)>>16), REGZERO, REGTMP)
			o2 = OP_RRR(c.oprrr(add), r, REGTMP, REGTMP)
			o3 = OP_IRR(c.opirr(a), uint32(v), REGTMP, p.From.Reg)

		case 4:
			o1 = OP_IRR(c.opirr(a), uint32(v), r, p.From.Reg)
		}

	case 30: /* movw r,fr */
		a := SP(2, 1) | (4 << 21) /* mtc1 */
		o1 = OP_RRR(a, p.From.Reg, obj.REG_NONE, p.To.Reg)

		a := OP_TEN(8, 1325) // movfr2gr.s
		o1 = OP_RR(a, uint32(p.From.Reg), uint32(p.To.Reg))

	case 32: // fadd fr1,[fr2],fr3
		r := int(p.Reg)
		if r == 0 {
			r = int(p.To.Reg)
		}
		o1 = OP_RRR(c.oprrr(p.As), uint32(p.From.Reg), uint32(r), uint32(p.To.Reg))

	case 33: // fabs fr1, fr3
		o1 = OP_RRR(c.oprrr(p.As), uint32(0), uint32(p.From.Reg), uint32(p.To.Reg))

	case 34: // mov $con,fr

		}
		o1 = AOP_RRR(c.oprrr(p.As), uint32(p.To.Reg), uint32(r), 0)

	case 48: /* op Rs, Ra */
		r := int(p.From.Reg)

		if r == 0 {
			r = int(p.To.Reg)
		}
		o1 = LOP_RRR(c.oprrr(p.As), uint32(p.To.Reg), uint32(r), 0)

	case 49: /* op Rb; op $n, Rb */
		if p.From.Type != obj.TYPE_REG { /* tlbie $L, rB */
			v := c.regoff(&p.From) & 1

				c.Close()
				t.Fatalf("%s succeeded, want error", op)
			}
			if perr := parseDialError(err); perr != nil {
				t.Fatal(perr)
			}
			operr := err.(*OpError).Err
			aerr, ok := operr.(*AddrError)
			if !ok {
				t.Fatalf("OpError.Err is %T, want *AddrError", operr)
			}
			want := tt.lit
			if tt.lit == "" {
				want = tt.addr.IP.String()
			}
			if aerr.Addr != want {

	if err != nil {
		err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
	}
	return n, addr, err
}

// ReadFrom implements the [PacketConn] ReadFrom method.
func (c *IPConn) ReadFrom(b []byte) (int, Addr, error) {
	if !c.ok() {
		return 0, nil, syscall.EINVAL
	}
	n, addr, err := c.readFrom(b)
	if err != nil {

		if p.To.Type != obj.TYPE_NONE {
			o2 |= (uint32(p.To.Reg) & 15) << 12
		}

	case 14: /* movb/movbu/movh/movhu R,R */
		o1 = c.oprrr(p, ASLL, int(p.Scond))

		if p.As == AMOVBU || p.As == AMOVHU {
			o2 = c.oprrr(p, ASRL, int(p.Scond))
		} else {
			o2 = c.oprrr(p, ASRA, int(p.Scond))
		}

		r := int(p.To.Reg)
		o1 |= (uint32(p.From.Reg)&15)<<0 | (uint32(r)&15)<<12

		}
		return nil, nil
	})
	defer sw.Set(socktest.FilterAccept, nil)

	operr := make(chan error, 1)
	handler := func(ls *localServer, ln Listener) {
		defer close(operr)
		c, err := ln.Accept()
		if err != nil {
			if perr := parseAcceptError(err); perr != nil {
				operr <- perr
			}
			operr <- err
			return
		}
		c.Close()
	}
	ls := newLocalServer(t, "tcp")

	if err != nil {
		err = &OpError{Op: "read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
	}
	return n, addr, err
}

// ReadFrom implements the [PacketConn] ReadFrom method.
func (c *UnixConn) ReadFrom(b []byte) (int, Addr, error) {
	if !c.ok() {
		return 0, nil, syscall.EINVAL
	}
	n, addr, err := c.readFrom(b)
	if err != nil {

	if err := setKeepAlive(c.fd, config.Enable); err != nil {
		return &OpError{Op: "set", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
	}
	if err := setKeepAliveIdle(c.fd, config.Idle); err != nil {
		return &OpError{Op: "set", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
	}
	if err := setKeepAliveInterval(c.fd, config.Interval); err != nil {
		return &OpError{Op: "set", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}