func difference(a, b []string) ([]string, []string) {
	aMinusB := map[string]bool{}
	bMinusA := map[string]bool{}
	for _, dependency := range a {
		aMinusB[dependency] = true
	}
	for _, dependency := range b {
		if _, found := aMinusB[dependency]; found {
			delete(aMinusB, dependency)
		} else {
			bMinusA[dependency] = true
		}
	}
	aMinusBList := []string{}
	bMinusAList := []string{}

	v.YplusX.Select(&a.YplusX, &b.YplusX, cond)
	v.YminusX.Select(&a.YminusX, &b.YminusX, cond)
	v.Z.Select(&a.Z, &b.Z, cond)
	v.T2d.Select(&a.T2d, &b.T2d, cond)
	return v
}

// Select sets v to a if cond == 1 and to b if cond == 0.
func (v *affineCached) Select(a, b *affineCached, cond int) *affineCached {
	v.YplusX.Select(&a.YplusX, &b.YplusX, cond)
	v.YminusX.Select(&a.YminusX, &b.YminusX, cond)
	v.T2d.Select(&a.T2d, &b.T2d, cond)

				var bigneg = Int64{-0x80000000, 0}
				var minus1 = Int64{-1, ^uint32(0)}
				if a.Cmp(bigneg) != 0 || b.Cmp(minus1) != 0 {	// a != -1<<63 || b != -1
					div, mod = a.DivMod(b)
					dodiv = true
				}
			}
			fmt.Fprintf(bout, "\ttestInt64Binary(%v, %v, %v, %v, %v, %v, %v, %v, %v, %v, %v, %v);\n",
				a, b, a.Plus(b), a.Minus(b), a.Times(b), div, mod,
				a.And(b), a.Or(b), a.Xor(b), a.AndNot(b), dodiv)

					continue NextSetOfPrimes
				}
			}
		}

		n := new(big.Int).Set(bigOne)
		totient := new(big.Int).Set(bigOne)
		pminus1 := new(big.Int)
		for _, prime := range primes {
			n.Mul(n, prime)
			pminus1.Sub(prime, bigOne)
			totient.Mul(totient, pminus1)
		}
		if n.BitLen() != bits {
			// This should never happen for nprimes == 2 because
			// crypto/rand should set the top two bits in each prime.

			// invert and subtract 1. If the most-significant-bit isn't set then
			// we'll need to pad the beginning with 0xff in order to keep the number
			// negative.
			nMinus1 := new(big.Int).Neg(n)
			nMinus1.Sub(nMinus1, bigOne)
			bytes := nMinus1.Bytes()
			for i := range bytes {
				bytes[i] ^= 0xff
			}
			if len(bytes) == 0 || bytes[0]&0x80 == 0 {
				c.add(0xff)
			}
			c.add(bytes...)

	"VINSERTI64X4",
	"VINSERTPS",
	"VLDDQU",
	"VLDMXCSR",
	"VMASKMOVDQU",
	"VMASKMOVPD",
	"VMASKMOVPS",
	"VMAXPD",
	"VMAXPS",
	"VMAXSD",
	"VMAXSS",
	"VMINPD",
	"VMINPS",
	"VMINSD",
	"VMINSS",
	"VMOVAPD",
	"VMOVAPS",
	"VMOVD",
	"VMOVDDUP",
	"VMOVDQA",
	"VMOVDQA32",
	"VMOVDQA64",
	"VMOVDQU",
	"VMOVDQU16",
	"VMOVDQU32",
	"VMOVDQU64",
	"VMOVDQU8",

    }
  }

  private abstract static class DelayedActionRunnable implements Runnable {
    private final long tMinus;

    protected DelayedActionRunnable(long tMinus) {
      this.tMinus = tMinus;
    }

    @Override
    public final void run() {
      try {
        Thread.sleep(tMinus);
      } catch (InterruptedException e) {
        throw new AssertionError(e);
      }
      doAction();
    }

    }
  }

  private abstract static class DelayedActionRunnable implements Runnable {
    private final long tMinus;

    protected DelayedActionRunnable(long tMinus) {
      this.tMinus = tMinus;
    }

    @Override
    public final void run() {
      try {
        Thread.sleep(tMinus);
      } catch (InterruptedException e) {
        throw new AssertionError(e);
      }
      doAction();
    }

	if cgo_libc_setegid != nil {
		return minus1, minus1, ENOTSUP
	}
	r1, r2, errno := runtime_doAllThreadsSyscall(trap, a1, a2, a3, a4, a5, a6)
	return r1, r2, Errno(errno)
}

// linked by runtime.cgocall.go
//
//go:uintptrescapes
func cgocaller(unsafe.Pointer, ...uintptr) uintptr

var cgo_libc_setegid unsafe.Pointer // non-nil if cgo linked.

const minus1 = ^uintptr(0)

    name = "Neg_Div_Grad_Y";
    TF_RETURN_IF_ERROR(Neg(ctx, upstream_grad, &temp_output,
                           name.c_str()));  // -U
    AbstractTensorHandlePtr MinusU(temp_output);

    name = "Mul_Div_Grad_Y";
    TF_RETURN_IF_ERROR(Mul(ctx, MinusU.get(), Z, &temp_output,
                           name.c_str()));  // -U*Z
    AbstractTensorHandlePtr UZ(temp_output);

    name = "Div_Grad_Y";