13. A method for changing a succession of instruction words, the method comprising: providing a set of machine words, each machine word being associated with a virtual address from a set of addresses; providing a succession of instruction words having address information, the succession of instruction words prescribing a sequence of machine words which are intended to be processed by an arithmetic and logic unit which is coupled to a buffer store; altering the association between at least a portion of the set of machine words and at least a portion of the set of addresses, so that a different address from the at least one portion of the set of addresses than previously is associated with each machine word from the at least one portion of the set of machine words; changing the address information in the succession of instruction words based on the alteration of the association; storing the changed succession of instruction words in a memory; storing the machine words from the set of machine words; and storing information describing the altered association.
13. A method for changing a succession of instruction words, the method comprising: providing a set of machine words, each machine word being associated with a virtual address from a set of addresses; providing a succession of instruction words having address information, the succession of instruction words prescribing a sequence of machine words which are intended to be processed by an arithmetic and logic unit which is coupled to a buffer store; altering the association between at least a portion of the set of machine words and at least a portion of the set of addresses, so that a different address from the at least one portion of the set of addresses than previously is associated with each machine word from the at least one portion of the set of machine words; changing the address information in the succession of instruction words based on the alteration of the association; storing the changed succession of instruction words in a memory; storing the machine words from the set of machine words; and storing information describing the altered association. 20. The method as claimed in claim 13 , wherein the changing of the succession of instruction words and the alteration of the association are performed after a portion of the sequence has been processed.