Code Flow Trees for Scalable Functional Coverage Test Selection

The patent segments the functional coverage test-space into a hierarchical structure using a code flow tree, where the root node represents the system under test and leaf nodes represent individual code statements. This segmentation allows the test-space to be divided into manageable functional units (functions, procedures, blocks) that can be independently analyzed and covered, resolving the contradiction between achieving complete coverage and managing complexity.

The patent transitions from explicit enumeration in one dimension (listing all test cases) to a tree-based dimensional representation where test-space is organized hierarchically. This dimensional change allows compact representation of the test-space structure, enabling complete functional coverage to be achieved without explicitly enumerating all possible test combinations, thus reducing complexity while maintaining reliability.

The patent performs preliminary action by automatically generating the code flow tree and identifying all executable statements and functions before test execution. This preliminary analysis of the test-space structure enables efficient test case selection and reduces the time required during actual testing, as the framework is already prepared with organized functional units and coverage requirements.

The code flow tree acts as an intermediary between the system under test and the test execution process. Instead of directly enumerating and executing all possible test combinations, the tree structure serves as a mediator that organizes functional units and guides test selection, thereby reducing testing effort while ensuring complete functional coverage is achieved.