Design of testable structures defined by simple loops

A methodology is given for generating combinational structures from high-level descriptions (using assignment statements, "if\´ statements, and single-nested loops) of register-transfer (RT) level operators. The generated structures are cellular, and are interconnected in a tree structure. A general algorithm is given to test cellular tree structures with a test length which grows only linearly with the size of the tree. It is proved that this test length is optimal to within a constant factor. Ways of making the structures self-checking are also indicated.