You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: revcomp_test.go
    path of file: ./repos/gccrs/gcc/testsuite/go.test/test/bench/go1
    
    the code of the file until where you have to start completion: // Copyright 2011 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.

// This benchmark, taken from the shootout, tests array indexing
// and array bounds elimination performance.

package go1

import (
	"bufio"
	"bytes"
	"io/ioutil"
	"testing"
)

var revCompTable = [256]uint8{
	'A': 'T', 'a': 'T',
	'C': 'G', 'c': 'G',
	'G': 'C', '
    
func revcomp(data []byte) {
	in := bufio.NewReader(bytes.NewBuffer(data))
	out := ioutil.Discard
	buf := make([]byte, 1024*1024)
	line, err := in.ReadSlice('\n')
	for err == nil {
		out.Write(line)

		// Accumulate reversed complement in buf[w:]
		nchar := 0
		w := len(buf)
		for {
			line, err = in.ReadSlice('\n')
			if err != nil || line[0] == '>' {
				break
			}
			line = line[0 : len(line)-1]
			nchar += len(line)
			if len(line)+nchar/60+128 >= w {
				nbuf := make([]byte, len(buf)*5)
				copy(nbuf[len(nbuf)-len(buf):], buf)
				w += len(nbuf) - len(buf)
				buf = nbuf
			}

			// This loop is the bottleneck.
			for _, c := range line {
				w--
				buf[w] = revCompTable[c]
			}
		}

		// Copy down to beginning of buffer, inserting newlines.
		// The loop left room for the newlines and 128 bytes of padding.
		i := 0
		for j := w; j < len(buf); j += 60 {
			n := copy(buf[i:i+60], buf[j:])
			buf[i+n] = '\n'
			i += n + 1
		}
		out.Write(buf[0:i])
	}
}