{math.MaxInt64, 12, true},
		{0, 12, true},
		{math.MinInt64, 12, true},
	}

	for _, v := range vectors {
		ok := fitsInBase256(v.width, v.in)
		if ok != v.ok {
			t.Errorf("fitsInBase256(%d, %d): got %v, want %v", v.in, v.width, ok, v.ok)
		}
	}
}

func TestParseNumeric(t *testing.T) {
	vectors := []struct {
		in   string
		want int64
		ok   bool
	}{
		// Test base-256 (binary) encoded values.

	KLMD	R2, R8                 // b93f0028
	KIMD	R0, R4                 // b93e0004
	KDSA	R0, R8                 // b93a0008
	KMA	R2, R6, R4              // b9296024
	KMCTR   R2, R6, R4              // b92d6024

	// vector add and sub instructions
	VAB	V3, V4, V4              // e743400000f3
	VAH	V3, V4, V4              // e743400010f3
	VAF	V3, V4, V4              // e743400020f3
	VAG	V3, V4, V4              // e743400030f3

	MOVL (AX)(X0*1), AX             // ERROR "invalid instruction"
	MOVL (AX)(Y0*1), AX             // ERROR "invalid instruction"
	// VSIB/VM is invalid without vector index.
	// TODO(quasilyte): improve error message (#21860).
	// "invalid VSIB address (missing vector index)"
	VPGATHERQQ Y2, (BP), Y1         // ERROR "invalid instruction"
	// AVX2GATHER mask/index/dest #UD cases.

	"bytes"
	"compress/bzip2"
	"crypto/md5"
	"errors"
	"fmt"
	"io"
	"math"
	"os"
	"path"
	"reflect"
	"strconv"
	"strings"
	"testing"
	"time"
)

func TestReader(t *testing.T) {
	vectors := []struct {
		file    string    // Test input file
		headers []*Header // Expected output headers
		chksums []string  // MD5 checksum of files, leave as nil if not checked
		err     error     // Expected error to occur
	}{{

</p>

<p>
If a vector instruction takes a length or an index as an argument then it will be the
first argument.
For example, <code>VLEIF</code> <code>$1,</code> <code>$16,</code> <code>V2</code> will load
the value sixteen into index one of <code>V2</code>.
Care should be taken when using vector instructions to ensure that they are available at
runtime.

	f.ops = f.ops[1:]
	return f.pos, nil
}

func equalSparseEntries(x, y []sparseEntry) bool {
	return (len(x) == 0 && len(y) == 0) || reflect.DeepEqual(x, y)
}

func TestSparseEntries(t *testing.T) {
	vectors := []struct {
		in   []sparseEntry
		size int64

		wantValid    bool          // Result of validateSparseEntries
		wantAligned  []sparseEntry // Result of alignSparseEntries

			ops     fileOps
			wantCnt int64
			wantErr error
		}
		testClose struct { // Close() == wantErr
			wantErr error
		}
		testFnc any // testHeader | testWrite | testReadFrom | testClose
	)

	vectors := []struct {
		file  string // Optional filename of expected output
		tests []testFnc
	}{{
		// The writer test file was produced with this command:
		// tar (GNU tar) 1.26
		//   ln -s small.txt link.txt

	// difference that for some j, a[j]>b[j] and a[j+1]<b[j+1]. If the implementation
	// compares large chunks with wrong endianness, it gets wrong result.
	// no vector register is larger than 512 bytes for now
	const maxLength = 512
	a := make([]byte, maxLength)
	b := make([]byte, maxLength)
	// randomish but deterministic data. No 0 or 255.
	for i := 0; i < maxLength; i++ {

		}
	} else {
		return errors.New("invalid register and extension combination")
	}
	return nil
}

// ARM64RegisterArrangement constructs an ARM64 vector register arrangement.
func ARM64RegisterArrangement(reg int16, name, arng string) (int64, error) {
	var curQ, curSize uint16
	if name[0] != 'V' {
		return 0, errors.New("expect V0 through V31; found: " + name)
	}