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Synthesis & Logic Optimization · All levels

Scenario: QoR Storm: Step-by-Step Walkthrough

Step-by-Step Walkthrough for Scenario: QoR Storm.

Step-by-step analysis walkthrough

Use when you own Scenario: QoR Storm in a synthesis closure review.

  1. Confirm exact run context (RTL/SDC/lib/switch set).

  2. Open section QoR dashboard and identify first drift.

  3. Inspect topic-level report for mechanism evidence.

  4. Determine owner and candidate reversible action.

  5. Apply one change only; avoid bundled fixes.

  6. Run full timing/area/power checks.

  7. Validate side effects on neighboring path groups.

  8. Publish memo with outcome and residual risk.

Artifacts to collect

  • scenario brief, run manifest diff, triage timeline

  • QoR dashboard

  • run manifest

  • constraint diff

  • regression matrix

Decision memo template

diagram
SYNTHESIS DECISION MEMO — Scenario: QoR Storm
run context:
observed metric:
hypothesis:
fix:
regression:
owners: synthesis lead, STA owner, CAD owner

Reference visuals

QoR storm triage board

diagram
overnight regression
  -> manifest diff
  -> isolate first drift
  -> reversible fix

Synthesis deep dive

Interview readiness comes from repeatable QoR reasoning under pressure.

Concept diagram

diagram
INTERVIEW ANSWER SHAPE

context -> metric -> mechanism -> fix -> regression -> ownership

Metric graph

diagram
PANEL SCORING

clarity      ███████
mechanism    ██████
regression   █████

Reports and artifacts

  • mock scorecard

  • scenario debrief

  • Q&A coverage

  • framework adherence

Mini case study

Candidate improved by replacing tool-command answers with evidence-driven closure narratives.

Debug branches

  • State assumptions first

  • Defend option tradeoffs

  • Close with rollback/regression

Senior review question

Ask: what evidence proves this QoR move is real and stable?

Key takeaways

  • State exact run context (RTL, SDC, libs, switches) with every QoR claim.

  • Re-run timing, area, and power regressions after each synthesis ECO.

Common pitfalls

  • Comparing runs with mismatched constraints or library views.

  • Timing-only fixes that violate power or area budgets.

  • Skipping equivalence checks after structural changes.

Principal synthesis review addendum

QoR storms test run-hygiene fundamentals: constraint diffs, library updates, and compile switches before speculative ECO.

Metric: overnight WNS/TNS regression with no RTL intent change

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