// Interpretation of trace:
	//   x ≡ y    attempt to unify types x and y
	//   p ➞ y    type parameter p is set to type y (p is inferred to be y)
	//   p ⇄ q    type parameters p and q match (p is inferred to be q and vice versa)
	//   x ≢ y    types x and y cannot be unified
	//   [p, q, ...] ➞ [x, y, ...]    mapping from type parameters to types
	traceInference = false
)

		if y, ok := y.(*Basic); ok {
			return x.kind == y.kind
		}

	case *Array:
		// Two array types are identical if they have identical element types
		// and the same array length.
		if y, ok := y.(*Array); ok {
			// If one or both array lengths are unknown (< 0) due to some error,
			// assume they are the same to avoid spurious follow-on errors.
			return (x.len < 0 || y.len < 0 || x.len == y.len) && c.identical(x.elem, y.elem, p)

	// Interpretation of trace:
	//   x ≡ y    attempt to unify types x and y
	//   p ➞ y    type parameter p is set to type y (p is inferred to be y)
	//   p ⇄ q    type parameters p and q match (p is inferred to be q and vice versa)
	//   x ≢ y    types x and y cannot be unified
	//   [p, q, ...] ➞ [x, y, ...]    mapping from type parameters to types
	traceInference = false
)

		if y, ok := y.(*Basic); ok {
			return x.kind == y.kind
		}

	case *Array:
		// Two array types are identical if they have identical element types
		// and the same array length.
		if y, ok := y.(*Array); ok {
			// If one or both array lengths are unknown (< 0) due to some error,
			// assume they are the same to avoid spurious follow-on errors.
			return (x.len < 0 || y.len < 0 || x.len == y.len) && c.identical(x.elem, y.elem, p)

Mientras esperas, vas con esa persona 😍 y eliges una mesa, se sientan y hablan durante un rato largo (ya que las hamburguesas son muy impresionantes y necesitan un rato para prepararse ✨🍔✨).

Mientras te sientas en la mesa con esa persona 😍, esperando las hamburguesas 🍔, puedes disfrutar ese tiempo admirando lo increíble, inteligente, y bien que se ve ✨😍✨.

		}
	}
	if x.cmp(y) >= 0 {
		return z.sub(x, y)
	}
	// x - y < 0; x - y mod 2ⁿ = x - y + 2ⁿ = 2ⁿ - (y - x) = 1 + 2ⁿ-1 - (y - x) = 1 + ^(y - x).
	z = z.sub(y, x)
	for uint(len(z))*_W < n {
		z = append(z, 0)
	}
	for i := range z {
		z[i] = ^z[i]
	}
	z = z.trunc(z, n)
	return z.add(z, natOne)

		// want the original x.neg and y.neg values when we evaluate
		// x.neg != y.neg, so we need to save y.neg before setting z.neg.
		yneg := y.neg

		z.neg = x.neg
		if x.neg == yneg {
			// x + y == x + y
			// (-x) + (-y) == -(x + y)
			z.uadd(x, y)
		} else {
			// x + (-y) == x - y == -(y - x)
			// (-x) + y == y - x == -(x - y)
			if x.ucmp(y) > 0 {
				z.usub(x, y)
			} else {

func goPanicIndex(x int, y int)
func goPanicIndexU(x uint, y int)
func goPanicSliceAlen(x int, y int)
func goPanicSliceAlenU(x uint, y int)
func goPanicSliceAcap(x int, y int)
func goPanicSliceAcapU(x uint, y int)
func goPanicSliceB(x int, y int)
func goPanicSliceBU(x uint, y int)
func goPanicSlice3Alen(x int, y int)
func goPanicSlice3AlenU(x uint, y int)
func goPanicSlice3Acap(x int, y int)

	MOVDU 32(R8), R15     // R15 = x[i+3]
	MOVD  8(R9), R16      // R16 = y[i]
	MOVD  16(R9), R17     // R17 = y[i+1]
	MOVD  24(R9), R18     // R18 = y[i+2]
	MOVDU 32(R9), R19     // R19 = y[i+3]
	ADDE  R11, R16, R20   // R20 = x[i] + y[i] + CA
	ADDE  R12, R17, R21   // R21 = x[i+1] + y[i+1] + CA
	ADDE  R14, R18, R22   // R22 = x[i+2] + y[i+2] + CA
	ADDE  R15, R19, R23   // R23 = x[i+3] + y[i+3] + CA
	MOVD  R20, 8(R10)     // z[i]

	p256Inverse(y, &p.z)
	p256Sqr(x, y, 1)
	p256Mul(y, y, x)

	p256Mul(x, &p.x, x)
	p256Mul(y, &p.y, y)

	p256FromMont(x, x)
	p256FromMont(y, y)
}

// BytesX returns the encoding of the x-coordinate of p, as specified in SEC 1,
// Version 2.0, Section 2.3.5, or an error if p is the point at infinity.
func (p *P256Point) BytesX() ([]byte, error) {