in assembler.go [206:216]
func (p *Program) insertAfter(index Index, inst bpf.Instruction) Index {
// This is safe since we are only accessing instructions that were inserted as bpf.JumpIf.
jumpInst := p.instructions[index].(bpf.JumpIf)
p.instructions[index] = jumpInst
index++
p.instructions = append(p.instructions[:index+1], p.instructions[index:]...)
p.instructions[index] = inst
p.updateIndices(index)
return index
}