if n, err := r.WriteTo(w); err != nil || n != int64(len(input)) {
		t.Fatalf("r.WriteTo(w) = %d, %v, want %d, nil", n, err, len(input))
	}

	for i, val := range w.Bytes() {
		if val != input[i] {
			t.Errorf("after write: out[%d] = %#x, want %#x", i, val, input[i])
		}
	}
}

type errorWriterToTest struct {
	rn, wn     int
	rerr, werr error
	expected   error
}

	MRS	CNTP_TVAL_EL0, R27                 // 1be23bd5
	MSR	R17, CNTP_TVAL_EL0                 // 11e21bd5
	MRS	CNTV_CTL_EL0, R27                  // 3be33bd5
	MSR	R2, CNTV_CTL_EL0                   // 22e31bd5
	MRS	CNTV_CVAL_EL0, R16                 // 50e33bd5
	MSR	R27, CNTV_CVAL_EL0                 // 5be31bd5
	MRS	CNTV_TVAL_EL0, R12                 // 0ce33bd5
	MSR	R19, CNTV_TVAL_EL0                 // 13e31bd5

					// Found it. Now find data section.
					if i := int(s.Section); 0 <= i && i < len(f.Sections) {
						sect := f.Sections[i]
						val := removeTag(s.Value)
						if sect.Addr <= val && val < sect.Addr+sect.Size {
							if sdat, err := sect.Data(); err == nil {
								data := sdat[val-sect.Addr:]
								ints = make([]int64, len(data)/8)
								for i := range ints {
									ints[i] = int64(bo.Uint64(data[i*8:]))