Error "SolveBeforeMustBeRand" while Elaborating with Dsim tool

[magnetworks]

Hi, I'm trying to build & run the repo using DSIM. I'm get the following error -

=E:[SolveBeforeMustBeRand]:
    The variables mentioned in a solve-before constraint
    must be simple variables (no indexes or members)
    and must be rand (not state or randc).

    ./src/riscv_pmp_cfg.sv:106:7
    Included from src/riscv_instr_pkg.sv:1529:12

Any help with this would be great.

[pdhakal-metrics]

Here's the problematic line: solve mseccfg.mml before pmp_cfg[i].w, pmp_cfg[i].r;

mseccfg is a rand variable of a packed struct. dsim does not currently allow slices/members of packed structs in the "solve before" directive. It would be a substantive rewrite of the code, which is not in the immediate pipeline. Would solving for mseccfg instead of a specific bit within it be an acceptable workaround? solve mseccfg before pmp_cfg[i].w, pmp_cfg[i].r;

[mcandress]

There should be an upcoming enhancement to DSim that will allow more slices/members to be used in solve/before constraints and will solve this issue.

Meanwhile, you can get the desired behaviour by adding a variable that is equal to mseccfg.mml and using it in the solve-before.

rand bit tmpVar;
...
constraint xwr_c {
    tmpVar == msccfg.mml; 
    foreach (pmp_cfg[i]) {
        solve tmpVar before pmp_cfg[i].w, pmp_cfg[i].r
      }
     ...
  }