Profiling the runtime of SystemVerilog Assertions

I got a similar report from one of my users. I asked him to run with profiler but he never got back to me.  Shalom

Hi Daniel,

 You are correct. This feature was added in version 8.2. I just tried it on a simple testcase that I have and get the following in my ncprof.out.  Are you not seeing a section in the log file that looks something like this?

------------------------------------------------------------
Assertion Summary Counts (15 hits, 28.8% of total)
------------------------------------------------------------
%hits #hits  #inst  name
  7.7     4 [    1] input_Done_and_Gnt (assert stmt, file: ../vcomp/vcomp_arb.v, line: 27)
  3.8     2 [    1] output_GntA_then_Busy_overlaps_Done (assert stmt, file: ../vcomp/vcomp_arb.v, line: 65)
  3.8     2 [    1] output_Gnt_onehot0 (assert stmt, file: ../vcomp/vcomp_arb.v, line: 40)
  3.8     2 [    1] input_Gnt_eventually_Done (assert stmt, file: ../vcomp/vcomp_arb.v, line: 23)
  3.8     2 [    1] input_ReqB_and_GntB (assert stmt, file: ../vcomp/vcomp_arb.v, line: 17)
  3.8     2 [    1] input_ReqA_and_GntA (assert stmt, file: ../vcomp/vcomp_arb.v, line: 15)
  1.9     1 [    1] output_GntB_then_Busy_overlaps_Done (assert stmt, file: ../vcomp/vcomp_arb.v, line: 67)

Chris

In addtion to what Chris showed, you will also get this information (copied from Assertion Checking in Simulation manual):

In addition to the basic profiling improvements, which will be useful for diagnosing almost any performance problem, warnings will identify certain problems more specifically. These warnings will provide some indication as to why some assertions might be particularly slow, so that the user can improve them, including:

• Large number of attempts in flight, indicating that the enabling condition might be too permissive, or that old attempts never completed
• Large number of false starts, when an inactive property is activated, tests its data, and goes becomes inactive again
• Continually increasing memory usage

If profiling is enabled, these warnings are included in the simulation log file, once per affected assertion.
These warnings also appear as part of the profile report, following the Assertion Summary section, so that they can be analyzed without the need to cross-reference the profile report against the simulation log file. 

Tim

Thanks Tim and Chris, thats really useful information! I must say there is some very good SVA documentation now with Incisive 8,2  (not sure what version this documentation arrived with, but I know it wasn't there a year ago or at least i wasn't aware of it then).

The reason I didn't see the profiling information is that all the properties are in an off state (which I believe is due to an $assertoff or $assertkill - despite the fact I can't find any). Interestingly whatever is causing this wasn't a problem in 6.2-s4.

Anyway , when I do get round to resolving this, I may follow up with a further question about assertion profiling/performance.

Thanks again for the very useful pointers - much appreciated!

Daniel