Low Power Verification · All levels

UPF-Aware Assertions for Power Intent: Debug Playbook

Debug Playbook for UPF-Aware Assertions for Power Intent.

Debug playbook

Debug Playbook for UPF-Aware Assertions for Power Intent is anchored on illegal transition rate, corruption incidence, and deterministic replay quality under low-power scenarios. Convert observations into mechanism-backed and owner-bound actions.

Freeze seed, metadata, and boundary under investigation.
Locate first persistent low-power phase divergence.
Classify mechanism: setup, transition, boundary, retention, or X-prop class.
Apply one focused reproducer and one bounded fix.
Re-run determinism and broader regression matrix.

Review memo template

diagram

LPV REVIEW MEMO - Low Power Assertions & Coverage / UPF-Aware Assertions for Power Intent

1. Symptom
   - Failing metric: illegal transition rate, corruption incidence, and deterministic replay quality under low-power scenarios
   - Trigger context: <seed/mode/sequence>
   - First failing phase: <entry/off/exit/boundary>

2. Mechanism hypothesis
   - Candidate mechanism: UPF-aware assertions convert low-power intent into executable temporal contracts that continuously monitor sequencing and legality, not just static structure. High-value properties enforce isolation-before-off, de-isolation-after-restore, retention save/restore ordering, legal power-state table transitions, and clamp correctness at active interfaces. Strong assertion sets also include liveness checks (for example, domain eventually reaches requested stable state after control handshake), guard conditions for asynchronous resets and clocks, and explicit handling of unknown-propagation windows so checkers do not mask real violations. In practice, teams bind assertion libraries at domain boundaries and power controller interfaces, tag each property with owner and intent clause, and use failure triage metadata to rapidly separate real design bugs from environment assumptions or testbench sequencing defects.
   - Competing hypotheses: setup, transition race, boundary bug, retention drift, X-prop noise
   - Missing evidence: <trace/assertion/report>

3. Proposed action
   - Smallest reversible change: <intent/RTL/checker/flow>
   - Expected movement: <failure trend/replay stability>
   - Regression risk: compatibility, coverage, signoff delay

4. Signoff
   - Required artifact: evidence packet for UPF-Aware Assertions for Power Intent: transition timeline, assertions, and before-after replay summary
   - Required owners: LPV lead, power-intent owner, Low Power Assertions & Coverage owner
   - Final decision: ship, bounded rollout, rollback, or escalate

Low-power verification deep dive

Assertions and coverage translate LPV intent into measurable closure confidence and prioritized risk reduction.

Concept diagram

diagram

COVERAGE CLOSURE LOOP

intent risk -> assertions and checkers -> coverage evidence -> closure gaps -> targeted scenarios

Metric graph

diagram

COVERAGE MATURITY

raw hits                 ███████
actionable closure hits  █████
uncovered high-risk bins ███

Metrics and artifacts to collect

assertion failure taxonomy
mode-transition coverage heatmap
crossing risk coverage report
coverage closure readiness packet

Mini case study

Coverage closure accelerated once failures were grouped by transition risk class instead of tool report order.

Debug branches

Prioritize coverage by product-risk scenarios.
Separate actionable assertion classes from setup noise.
Use closure criteria with explicit waiver governance.

Senior review question

Ask: what exact low-power transition boundary failed first, and which artifact proves the closure claim reproducibly?

Key takeaways

Tie each LPV claim to a concrete transition boundary and one proving artifact.
Prefer minimal reversible fixes with explicit owner and rollback criteria.

Common pitfalls

Treating power-aware failures as random before boundary classification.
Waiving X-prop failures before proving impact and root cause.
Declaring closure without deterministic replay across key modes.

Debug ladder

Sequence: reproduce -> classify -> isolate boundary -> prove mechanism -> bounded fix.

Avoid mixed fixes before first-principles classification.

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