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: decompress.go
    path of file: ./repos/scan4all/vendor/github.com/klauspost/compress/fse
    
    the code of the file until where you have to start completion: package fse

import (
	"errors"
	"fmt"
)

const (
	tablelogAbsoluteMax = 15
)

// Decompress a block of data.
// You can provide a scratch buffer to avoid allocations.
// If nil is provided a temporary one will be allocated.
// It is possible, but by no way guaranteed that corrupt data will
// return an error.
// It is up to the caller to verify integrity of the returned data.
// Use a predefined Scrach to set m
    
func (s *Scratch) decompress() error {
	br := &s.bits
	if err := br.init(s.br.unread()); err != nil {
		return err
	}

	var s1, s2 decoder
	// Initialize and decode first state and symbol.
	s1.init(br, s.decTable, s.actualTableLog)
	s2.init(br, s.decTable, s.actualTableLog)

	// Use temp table to avoid bound checks/append penalty.
	var tmp = s.ct.tableSymbol[:256]
	var off uint8

	// Main part
	if !s.zeroBits {
		for br.off >= 8 {
			br.fillFast()
			tmp[off+0] = s1.nextFast()
			tmp[off+1] = s2.nextFast()
			br.fillFast()
			tmp[off+2] = s1.nextFast()
			tmp[off+3] = s2.nextFast()
			off += 4
			// When off is 0, we have overflowed and should write.
			if off == 0 {
				s.Out = append(s.Out, tmp...)
				if len(s.Out) >= s.DecompressLimit {
					return fmt.Errorf("output size (%d) > DecompressLimit (%d)", len(s.Out), s.DecompressLimit)
				}
			}
		}
	} else {
		for br.off >= 8 {
			br.fillFast()
			tmp[off+0] = s1.next()
			tmp[off+1] = s2.next()
			br.fillFast()
			tmp[off+2] = s1.next()
			tmp[off+3] = s2.next()
			off += 4
			if off == 0 {
				s.Out = append(s.Out, tmp...)
				// When off is 0, we have overflowed and should write.
				if len(s.Out) >= s.DecompressLimit {
					return fmt.Errorf("output size (%d) > DecompressLimit (%d)", len(s.Out), s.DecompressLimit)
				}
			}
		}
	}
	s.Out = append(s.Out, tmp[:off]...)

	// Final bits, a bit more expensive check
	for {
		if s1.finished() {
			s.Out = append(s.Out, s1.final(), s2.final())
			break
		}
		br.fill()
		s.Out = append(s.Out, s1.next())
		if s2.finished() {
			s.Out = append(s.Out, s2.final(), s1.final())
			break
		}
		s.Out = append(s.Out, s2.next())
		if len(s.Out) >= s.DecompressLimit {
			return fmt.Errorf("output size (%d) > DecompressLimit (%d)", len(s.Out), s.DecompressLimit)
		}
	}
	return br.close()
}