How do you make the final proceed-or-stop decision?
From PDVerse PnR Interview Handbook · pdVerse Mentor Guide
Short Answer
Proceed only when provenance matches, linking resolves, structure is classified, SDC semantics are reviewed, clocks/I/O/exceptions/scenarios provide intended coverage, and waivers are owned and reproducible.
Technical Explanation
Treat this as a readiness check. It should produce named objects and a result that another engineer can repeat from the same handoff.
What To Check
• Warning sign: One hard-stop defect remains but schedule pressure treats it as a warning. • Inspect: Keep at least two possible causes open, then use one named object and the active mode or scenario to separate them. • Correct: Record the decision matrix, return hard stops, archive reports and waivers, reopen the final checkpoint, and reproduce the gate once.
Command Checks & Actions
• check_design -checks {netlist unbound dp_pre_floorplan}: runs the selected design-readiness checks
• check_netlist: reports structural connectivity problems
• check_timing: finds missing or inconsistent timing setup
• report_clocks: shows clock definitions and relationships
• report_scenarios: shows the MCMM scenario matrix and analysis status
• report_exceptions: shows timing exceptions and their scope
• report_case_analysis: shows constants applied for the active mode
• report_disable_timing: shows timing arcs that cannot propagate
Run the commands in order. Each line answers a separate part of the check.Healthy, Suspicious & Hard-stop Results
• Expected: Proceed only when provenance matches, linking resolves, structure is classified, SDC semantics are reviewed, clocks/I/O/exceptions/scenarios provide intended coverage, and waivers are owned and reproducible. • Investigate: One hard-stop defect remains but schedule pressure treats it as a warning. • Stop before floorplanning when required logic or timing coverage is missing or unexplained. Record the decision matrix, return hard stops, archive reports and waivers, reopen the final checkpoint, and reproduce the gate once.
Common Mistake
Do not assume the check passed just because ICC2 continued: One hard-stop defect remains but schedule pressure treats it as a warning. Fix or narrowly justify the named objects, then rerun the same command.
What The Interviewer Is Testing
Be ready to explain why this matters before floorplanning: One hard-stop defect remains but schedule pressure treats it as a warning.
Follow-up Question & Model Response
Model response: “I would save the report, inspect one affected object in the correct block and scenario, and make or request this correction: Record the decision matrix, return hard stops, archive reports and waivers, reopen the final checkpoint, and reproduce the gate once. Then I would reopen the clean checkpoint and rerun the same evidence.”
Practical Example
Symptom: One hard-stop defect remains but schedule pressure treats it as a warning. Corrective path: Record the decision matrix, return hard stops, archive reports and waivers, reopen the final checkpoint, and reproduce the gate once.
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