}
		return v, err
	}

	duration := ts2.Sub(ts1)
	y1, m1, d1 := ts1.Date()
	y2, m2, d2 := ts2.Date()

	switch timePart {
	case timePartYear:
		dy := int64(y2 - y1)
		if m2 > m1 || (m2 == m1 && d2 >= d1) {
			return FromInt(dy), nil
		}
		return FromInt(dy - 1), nil
	case timePartMonth:
		m1 += time.Month(12 * y1)
		m2 += time.Month(12 * y2)

		return FromInt(int64(m2 - m1)), nil

	VFMSUB231PD 7(AX)(CX*1), X2, K3, X20               // 62e2ed0bbaa40807000000
	VFMSUB231PD Y1, Y6, K3, Y1                         // 62f2cd2bbac9
	VFMSUB231PD 15(R8)(R14*1), Y6, K3, Y1              // 6292cd2bba8c300f000000
	VFMSUB231PD 15(R8)(R14*2), Y6, K3, Y1              // 6292cd2bba8c700f000000
	VFMSUB231PD Z28, Z26, K2, Z6                       // 6292ad42baf4

    assertThat(transformation.transform(x1)).isWithin(ALLOWED_ERROR).of(y1);
    assertThat(transformation.transform(x1 + xDelta)).isWithin(ALLOWED_ERROR).of(y1 + yDelta);
    assertThat(transformation.inverse().transform(y1)).isWithin(ALLOWED_ERROR).of(x1);
    assertThat(transformation.inverse().transform(y1 + yDelta))
        .isWithin(ALLOWED_ERROR)
        .of(x1 + xDelta);

	VPMULTISHIFTQB Y1, Y30, K7, Y12                    // 62728d2783e1
	VPMULTISHIFTQB Y30, Y30, K7, Y12                   // 62128d2783e6
	VPMULTISHIFTQB 17(SP)(BP*2), Y30, K7, Y12          // 62728d2783a46c11000000
	VPMULTISHIFTQB -7(DI)(R8*4), Y30, K7, Y12          // 62328d2783a487f9ffffff
	VPMULTISHIFTQB Y16, Y26, K7, Y12                   // 6232ad2783e0
	VPMULTISHIFTQB Y1, Y26, K7, Y12                    // 6272ad2783e1

	VPOPCNTB Y1, K4, Y24                               // 62627d2c54c1
	VPOPCNTB 15(R8)(R14*8), K4, Y24                    // 62027d2c5484f00f000000
	VPOPCNTB -15(R14)(R15*2), K4, Y24                  // 62027d2c54847ef1ffffff
	VPOPCNTB Y14, K4, Y13                              // 62527d2c54ee
	VPOPCNTB Y21, K4, Y13                              // 62327d2c54ed
	VPOPCNTB Y1, K4, Y13                               // 62727d2c54e9

const3, hlp0, hlp0 ADC $0, acc4 ADDS t1, acc1, acc1 ADCS y0, acc2, acc2 ADCS acc0, acc3, acc3 ADC $0, hlp0, acc0 // y[1] * x MUL y1, x0, t0 ADDS t0, acc1 UMULH y1, x0, t1 MUL y1, x1, t0 ADCS t0, acc2 UMULH y1, x1, hlp0 MUL y1, x2, t0 ADCS t0, acc3 UMULH y1, x2, y0 MUL y1, x3, t0 ADCS t0, acc4 UMULH y1, x3, y1 ADC $0, ZR, acc5 ADDS t1, acc2 ADCS hlp0, acc3 ADCS y0, acc4 ADC y1, acc5 // Second reduction step MUL acc1, hlp1, hlp0 MUL const0, hlp1, t0 ADDS t0, acc1, acc1 UMULH const0, hlp0, t1 MUL const1,...

const3, hlp0, hlp0 ADC $0, acc4 ADDS t1, acc1, acc1 ADCS y0, acc2, acc2 ADCS acc0, acc3, acc3 ADC $0, hlp0, acc0 // y[1] * x MUL y1, x0, t0 ADDS t0, acc1 UMULH y1, x0, t1 MUL y1, x1, t0 ADCS t0, acc2 UMULH y1, x1, hlp0 MUL y1, x2, t0 ADCS t0, acc3 UMULH y1, x2, y0 MUL y1, x3, t0 ADCS t0, acc4 UMULH y1, x3, y1 ADC $0, ZR, acc5 ADDS t1, acc2 ADCS hlp0, acc3 ADCS y0, acc4 ADC y1, acc5 // Second reduction step MUL acc1, hlp1, hlp0 MUL const0, hlp1, t0 ADDS t0, acc1, acc1 UMULH const0, hlp0, t1 MUL const1,...

	VPMINUW -7(CX)(DX*4), X11, K2, X1                  // 62f2250a3a8c91f9ffffff or 62f2a50a3a8c91f9ffffff
	VPMINUW Y13, Y28, K3, Y1                           // 62d21d233acd or 62d29d233acd
	VPMINUW 17(SP), Y28, K3, Y1                        // 62f21d233a8c2411000000 or 62f29d233a8c2411000000
	VPMINUW -17(BP)(SI*4), Y28, K3, Y1                 // 62f21d233a8cb5efffffff or 62f29d233a8cb5efffffff

    /*
     * For an explanation of the basic principle behind this check, see
     * https://stackoverflow.com/a/35754308/28465
     *
     * In that explanation's notation, our `overlap` check would be `x1 < y2 && y1 < x2`. We've
     * flipped one part of the check so that we're using "less than" in both cases (rather than a
     * mix of "less than" and "greater than"). We've also switched to "strictly less than" rather

pkg math, func Sqrt(float64) float64
pkg math, func Tan(float64) float64
pkg math, func Tanh(float64) float64
pkg math, func Trunc(float64) float64
pkg math, func Y0(float64) float64
pkg math, func Y1(float64) float64
pkg math, func Yn(int, float64) float64
pkg math/big, const MaxBase ideal-char
pkg math/big, func NewInt(int64) *Int
pkg math/big, func NewRat(int64, int64) *Rat