Synthesis & Logic Optimization · All levels

Scenario: Retiming Debate: Review Checklist

Review Checklist for Scenario: Retiming Debate.

Review checklist

Review Checklist for Scenario: Retiming Debate focuses on frequency target miss versus latency and verification budget. The goal is to connect observed QoR movement to mechanism, ownership, and regression risk.

  • Run manifest is attached (RTL/SDC/libs/switches).

  • Primary metric and impacted lane are named.

  • Mechanism hypothesis is evidence-backed.

  • Fix is reversible and owner-assigned.

  • Regression matrix includes timing, area, power, and equivalence as needed.

  • Owners signed: microarchitecture owner, synthesis owner, formal owner.

Sign-off ownership

diagram
OWNERSHIP MAP — Scenario: Retiming Debate

artifact              owner
----------------      -----------------
compile owner       microarchitecture owner
timing/power owner  synthesis owner
cross-team review   formal owner

Every QoR movement needs a named owner before ECO.

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

Retiming debate evaluates whether register movement is safer than RTL pipeline edits under schedule and formal constraints.

Metric: frequency target miss versus latency and verification budget