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: atomicptrmap_goroutine_unsafe.go
    path of file: ./repos/sliver/implant/vendor/gvisor.dev/gvisor/pkg/sync/locking
    
    the code of the file until where you have to start completion: package locking

import (
	"sync/atomic"
	"unsafe"

	"gvisor.dev/gvisor/pkg/gohacks
    
func (m *goroutineLocksAtomicPtrMap) shard(hash uintptr) *goroutineLocksapmShard {
	// Go defines right shifts >= width of shifted unsigned operand as 0, so
	// this is correct even if ShardOrder is 0 (although nogo complains because
	// nogo is dumb).
	const indexLSB = unsafe.Sizeof(uintptr(0))*8 - goroutineLocksShardOrder
	index := hash >> indexLSB
	return (*goroutineLocksapmShard)(unsafe.Pointer(uintptr(unsafe.Pointer(&m.shards)) + (index * unsafe.Sizeof(goroutineLocksapmShard{}))))
}