testsuite: rocm.exp: Limit wave output logged by info_threads_get_wave_count

[akondrat-amd]

On GPUs with many wavefronts, info_threads_get_wave_count floods the log with thousands of lines. Print only the first and last 20 wave lines, replacing the omitted middle with a single summary line "... N waves omitted ...".

Key changes:

• log_user 0/1 suppresses raw expect output during matching
• Lines are collected into wave_lines instead of being logged on the fly
• After matching, first 20 and last 20 are emitted via verbose -log; middle rows get a single summary line

[lumachad]

What problem exactly are we trying to solve? A timeout? A expect buffer overflow?

[akondrat-amd]

What problem exactly are we trying to solve? A timeout? A expect buffer overflow?

We count waves at least three times in a couple of tests, it adds thousands of lines to the log, particularly, 3 x 16,384. It's a nightmare to scroll through it.

[lumachad]

Honestly I think we need a command to give us the number of waves we have. It is not feasible to count waves by going through a wall of text. For instance, if we run this with check-read1, it will be very slow.

[akondrat-amd]

This is how the output looks:

[akondrat-amd]

Honestly I think we need a command to give us the number of waves we have. It is not feasible to count waves by going through a wall of text. For instance, if we run this with check-read1, it will be very slow.

Running with check-read1 takes ~30 seconds longer with 3,000 waves regardless of this fix.
We should have a line like "Total Waves:" with a default option to omit the lines in the middle.

... (first 20 wave lines)
... 49,344 waves omitted ...
Total Waves: 49,384
... (last 20 wave lines)

[lumachad]

@amd-shahab Thoughts here? I do not think we should try to handle this in TCL.