Avoid using the external command grep for simple string-based checks.
Prefer a case statement. This improves performance.
The performance improvement is moderate but noticeable when skipping
most tests. When a test is run, the cost of the associated grep calls
is negligible. In this commit, I focused on the uses of grep that can
be easily replaced and that are executed a large number of times.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
6445749d3c