Code Coverage. This measures the extent to which the source code of the program has been tested and may include function coverage, statement coverage, decision coverage, condition coverage, parameter value coverage; and state coverage.
Code Coverage. The above validation techniques are complemented by code coverage analysis techniques. In particular, we try to ensure that Points 1 and 4 above cover all predicates and clauses of the ProB kernel. As we are not law1 == (dom(ff\/gg) = dom(ff) \/ dom(gg)); law2 == (ran(ff\/gg) = ran(ff) \/ ran(gg)); law3 == (dom(ff/\gg) <: dom(ff) /\ dom(gg)); law4 == (ran(ff/\gg) <: ran(ff) /\ ran(gg)); law5 == ( (ff \/ gg)~ = ff~ \/ gg~); law6 == (dom((ff ; (gg~))) <: dom(ff));
Code Coverage. This technique is used mostly with dynamic verification. As previously mentioned, the measurement of verification progress is usually given by coverage metrics, which can be divided into code coverage (sometimes called structural coverage) and functional coverage. Although most of the metrics are simple and easy to understand, the way they relate to the actual hardware functionalities is neither simple nor direct. Block, expression and toggle coverage are examples of code coverage metrics with such behaviour. Certain certification processes may require specific code coverage values, e.g., DO-254 [18] requires 100% statement coverage at minimum. Block coverage is the simplest of the structural metrics. A block of code is defined as one or more statements that always execute together. The principle of this metric is to measure if each block of the RTL code was simulated at least once. Block coverage supersedes statement coverage (in which the execution of each statement is evaluated). Guaranteeing that each block was simulated eliminates the presence of simple errors due to unstimulated logic. Also, this type of metric is useful for detecting potential dead code in the design. Expression coverage is a mechanism that analyses logical expressions in depth. Each expression is factorized and then monitored during simulation runs. The goal is to check that different terms of an expression have the capability of controlling the outcome of the expression being evaluated. Expression coverage complements block coverage because it can be used to identify why a given block of code has been stimulated. Finally, toggle coverage measures if every bit of every signal has been properly stimulated. This measurement is done by observing if a given bit has toggled from zero to one and vice-versa.
