8. The compression process as claimed in claim 6 , in which if two words of identical executable code appear consecutively in the executable code to be compressed, the second word of executable code is compressed without part of variable length, by means of a part of fixed length specifying that the word of executable code is the same as the preceding word.
6. The compression process as claimed in claim 1 , in which the compression step comprises: constituting a histogram giving for each distinct word of the executable code a number of occurrences of this word in the executable code, and extracting at least part of the words of the histogram into a decompression table, in which the words are distributed into sub-tables collecting words having numbers of close occurrences in the histogram, each sub-table being associated with a predefined length, the part of fixed length of each word of the executable code referencing a sub-table of the decompression table, and the part of variable length giving a position in the sub-decompression table of the word of the executable code.