How we can get time of individual test cases in DejaGnu

Question

I am running GCC testsuite and I want to know time elapsed for each individual test case. GCC uses DejaGnu for its test suite and I know that time can be used in scripts to get the time of a test case. I am wondering if there is any flag that I can pass with runtest that forces timing for all test cases (without changing test scripts).

Answer 1

I don't know of a generic way.

DejaGNU does not really have a built-in notion of the boundaries of a test. For example, it's reasonably common for a single conceptual test to call "pass" or "fail" several times. E.g., in GCC, a compilation test may check for several warnings from a given source file -- but each separate warning, and also the check for excess warnings, would be a separate pass or fail. However, these would all arise from a single invocation of GCC.

I think there are two approaches that you can take.

1. You can hack the .exp files you care about and use knowledge of what they are doing to track the times you are interested in.

2. You can run a single .exp file in isolation and time how long it takes. This is less useful in general, but it is what I did when making the GDB test suite more fully parallelizable.