for i := 0; i < 7; i++ {
		v.points[i+1].FromP3(tmpP3.fromP1xP1(tmpP1xP1.Add(&q2, &v.points[i])))
	}
}

// This is not optimised for speed; fixed-base tables should be precomputed.
func (v *nafLookupTable8) FromP3(q *Point) {
	v.points[0].FromP3(q)
	q2 := Point{}
	q2.Add(q, q)
	tmpP3 := Point{}
	tmpP1xP1 := projP1xP1{}
	for i := 0; i < 63; i++ {
		v.points[i+1].FromP3(tmpP3.fromP1xP1(tmpP1xP1.AddAffine(&q2, &v.points[i])))
	}

func basepointTable() *[32]affineLookupTable {
	basepointTablePrecomp.initOnce.Do(func() {
		p := NewGeneratorPoint()
		for i := 0; i < 32; i++ {
			basepointTablePrecomp.table[i].FromP3(p)
			for j := 0; j < 8; j++ {
				p.Add(p, p)
			}
		}
	})
	return &basepointTablePrecomp.table
}

var basepointTablePrecomp struct {
	table    [32]affineLookupTable
	initOnce sync.Once
}

// license that can be found in the LICENSE file.

package edwards25519

import (
	"testing"
)

func TestProjLookupTable(t *testing.T) {
	var table projLookupTable
	table.FromP3(B)

	var tmp1, tmp2, tmp3 projCached
	table.SelectInto(&tmp1, 6)
	table.SelectInto(&tmp2, -2)
	table.SelectInto(&tmp3, -4)
	// Expect T1 + T2 + T3 = identity

	var accP1xP1 projP1xP1

	table := make([]affineLookupTable, 32)
	for i := 0; i < 32; i++ {
		// Build the table
		table[i].FromP3(tmp3)
		// Assert equality with the hardcoded one
		if table[i] != basepointTable[i] {
			t.Errorf("Basepoint table %d does not match", i)
		}

		// Set p = (16^2)*p = 256*p = 2^8*p
		tmp2.FromP3(tmp3)
		for j := 0; j < 7; j++ {
			tmp1.Double(tmp2)
			tmp2.FromP1xP1(tmp1)
		}
		tmp1.Double(tmp2)

	0x73, 0xfe, 0x6f, 0x2b, 0xee, 0x6c, 0x03, 0x52})
var d2 = new(field.Element).Add(d, d)

func (v *projCached) FromP3(p *Point) *projCached {
	v.YplusX.Add(&p.y, &p.x)
	v.YminusX.Subtract(&p.y, &p.x)
	v.Z.Set(&p.z)
	v.T2d.Multiply(&p.t, d2)
	return v
}

func (v *affineCached) FromP3(p *Point) *affineCached {
	v.YplusX.Add(&p.y, &p.x)
	v.YminusX.Subtract(&p.y, &p.x)
	v.T2d.Multiply(&p.t, d2)

	}
	// Check that t is correct.
	checkOnCurve(t, B)
}

func TestAddSubNegOnBasePoint(t *testing.T) {
	checkLhs, checkRhs := &Point{}, &Point{}

	checkLhs.Add(B, B)
	tmpP2 := new(projP2).FromP3(B)
	tmpP1xP1 := new(projP1xP1).Double(tmpP2)
	checkRhs.fromP1xP1(tmpP1xP1)
	if checkLhs.Equal(checkRhs) != 1 {
		t.Error("B + B != [2]B")
	}
	checkOnCurve(t, checkLhs, checkRhs)

	checkLhs.Subtract(B, B)

	Destination
)

// From3Type returns p.GetFrom3().Type, or TYPE_NONE when
// p.GetFrom3() returns nil.
func (p *Prog) From3Type() AddrType {
	from3 := p.GetFrom3()
	if from3 == nil {
		return TYPE_NONE
	}
	return from3.Type
}

// GetFrom3 returns second source operand (the first is Prog.From).
// The same kinds of operands are saved in order so GetFrom3 actually

	p1.From.Sym = source.Sym
	p1.From.Name = obj.NAME_GOTREF
	p1.To.Type = obj.TYPE_REG
	p1.To.Reg = reg

	p2.As = p.As
	p2.From = p.From
	p2.To = p.To
	if from3 := p.GetFrom3(); from3 != nil {
		p2.AddRestSource(*from3)
	}
	if p.From.Name == obj.NAME_EXTERN {
		p2.From.Reg = reg
		p2.From.Name = obj.NAME_NONE
		p2.From.Sym = nil
	} else if p.To.Name == obj.NAME_EXTERN {
		p2.To.Reg = reg

			case Zevex_i_rm_v_r:
				imm, from, from3, to := unpackOps4(p)
				ab.evex = newEVEXBits(z, &o.op)
				ab.asmevex(ctxt, p, from, from3, to, nil)
				ab.asmand(ctxt, cursym, p, from, to)
				ab.Put1(byte(imm.Offset))

			case Zevex_i_rm_v_k_r:
				imm, from, from3, kmask, to := unpackOps5(p)
				ab.evex = newEVEXBits(z, &o.op)
				ab.asmevex(ctxt, p, from, from3, to, kmask)
				ab.asmand(ctxt, cursym, p, from, to)

	instoffset int64
	pc         int64
}

// Instruction layout.

const (
	FuncAlign = 4
	loopAlign = 16
)

type Optab struct {
	as    obj.As
	from1 uint8
	reg   uint8
	from3 uint8
	to1   uint8
	to2   uint8
	type_ int8
	size  int8
	param int16
	flag  uint8
}

const (
	NOTUSETMP = 1 << iota // p expands to multiple instructions, but does NOT use REGTMP