Synthesis & Logic Optimization · All levels

Scenario: Retiming Debate: Step-by-Step Walkthrough

Step-by-Step Walkthrough for Scenario: Retiming Debate.

Step-by-step analysis walkthrough

Use when you own Scenario: Retiming Debate in a synthesis closure review.

Confirm exact run context (RTL/SDC/lib/switch set).
Open section QoR dashboard and identify first drift.
Inspect topic-level report for mechanism evidence.
Determine owner and candidate reversible action.
Apply one change only; avoid bundled fixes.
Run full timing/area/power checks.
Validate side effects on neighboring path groups.
Publish memo with outcome and residual risk.

Artifacts to collect

retiming option sheet, equivalence plan, risk matrix
QoR dashboard
run manifest
constraint diff
regression matrix

Decision memo template

diagram

SYNTHESIS DECISION MEMO — Scenario: Retiming Debate
run context:
observed metric:
hypothesis:
fix:
regression:
owners: microarchitecture owner, synthesis owner, formal owner

Reference visuals

Retiming debate matrix

diagram

retime now?
benefit: Fmax
cost: formal + latency + schedule
decision by risk budget

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

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