Within the Go file, C's struct field names that are keywords in Go
can be accessed by prefixing them with an underscore: if x points at a C
struct with a field named "type", x._type accesses the field.
C struct fields that cannot be expressed in Go, such as bit fields
or misaligned data, are omitted in the Go struct, replaced by
appropriate padding to reach the next field or the end of the struct.

)

const N = 10000       // make this bigger for a larger (and slower) test
var testString string // test data for write tests
var testBytes []byte  // test data; same as testString but as a slice.

type negativeReader struct{}

func (r *negativeReader) Read([]byte) (int, error) { return -1, nil }

func init() {
	testBytes = make([]byte, N)
	for i := 0; i < N; i++ {
		testBytes[i] = 'a' + byte(i%26)
	}

					t.Errorf("fail at %s as function address: got %s, %v; expected %s, %v", test.input, name, ok, wantName, isFuncSym)
				}
			}
		})
	}
}

type operandTest struct {
	input, output string
}

type badOperandTest struct {
	input, error string
}

// Examples collected by scanning all the assembly in the standard repo.

var amd64OperandTests = []operandTest{
	{"$(-1.0)", "$(-1.0)"},

// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

"use strict";

(() => {
	const enosys = () => {
		const err = new Error("not implemented");
		err.code = "ENOSYS";
		return err;
	};

	if (!globalThis.fs) {
		let outputBuf = "";
		globalThis.fs = {

)

// FileHeader describes a file within a ZIP file.
// See the [ZIP specification] for details.
//
// [ZIP specification]: https://support.pkware.com/pkzip/appnote
type FileHeader struct {
	// Name is the name of the file.
	//
	// It must be a relative path, not start with a drive letter (such as "C:"),
	// and must use forward slashes instead of back slashes. A trailing slash

	tr := NewReader(f)
	_, err = tr.Read([]byte{})
	if err == nil || err != io.EOF {
		t.Errorf("Unexpected error: %v, wanted %v", err, io.EOF)
	}

}

type reader struct{ io.Reader }
type readSeeker struct{ io.ReadSeeker }
type readBadSeeker struct{ io.ReadSeeker }

func (rbs *readBadSeeker) Seek(int64, int) (int64, error) { return 0, fmt.Errorf("illegal seek") }

	magicUSTAR, versionUSTAR = "ustar\x00", "00"
	trailerSTAR              = "tar\x00"
)

// Size constants from various tar specifications.
const (
	blockSize  = 512 // Size of each block in a tar stream
	nameSize   = 100 // Max length of the name field in USTAR format
	prefixSize = 155 // Max length of the prefix field in USTAR format

	// Max length of a special file (PAX header, GNU long name or link).

</p>

<p>
Field offsets are of the form <code><i>type</i>_<i>field</i></code>.
Struct sizes are of the form <code><i>type</i>__size</code>.
For example, consider the following Go definition:
</p>

<pre>
type reader struct {
	buf [bufSize]byte
	r   int
}
</pre>

<p>
Assembly can refer to the size of this struct
as <code>reader__size</code> and the offsets of the two fields

)

// Writer provides sequential writing of a tar archive.
// [Writer.WriteHeader] begins a new file with the provided [Header],
// and then Writer can be treated as an io.Writer to supply that file's data.
type Writer struct {
	w    io.Writer
	pad  int64      // Amount of padding to write after current file entry
	curr fileWriter // Writer for current file entry
	hdr  Header     // Shallow copy of Header that is safe for mutations

		t.Errorf("Modified: got %s, want %s\n", got, want)
	}
}

type repeatedByte struct {
	off int64
	b   byte
	n   int64
}

// rleBuffer is a run-length-encoded byte buffer.
// It's an io.Writer (like a bytes.Buffer) and also an io.ReaderAt,
// allowing random-access reads.
type rleBuffer struct {
	buf []repeatedByte
}

func (r *rleBuffer) Size() int64 {
	if len(r.buf) == 0 {