BMC vs Unbounded Proof Strategies: Inputs and Outputs

Inputs and outputs contract

Inputs and Outputs for BMC vs Unbounded Proof Strategies is anchored on Bound depth achieved, k-induction success rate, and ratio of bug-find to full-proof properties.. Convert outcomes into assumption-aware, evidence-backed actions.

INPUTS
  - requirement intent and risk tier
  - property scope and temporal contract
  - assumption model and reset policy
  - tool/engine metadata and reproducibility tags

OUTPUTS
  - evidence-backed root-cause classification
  - owner-signed mitigation proposal
  - validation matrix and rollback triggers
  - signoff recommendation

Ownership split

OWNERSHIP LAYERS - BMC vs Unbounded Proof Strategies

+----------------------+--------------------------------+--------------------------------+
| Team                 | Primary responsibility         | Closure artifact               |
+----------------------+--------------------------------+--------------------------------+
| formal verification owner | property and model integrity      | assumptions and proof packet   |
| microarchitecture owner | implementation root-cause closure | RTL fix and replay evidence    |
| verification lead | signoff governance and rollout    | risk memo + acceptance gates   |
+----------------------+--------------------------------+--------------------------------+

Formal deep dive

Convergence requires engine strategy, invariant quality, and model realism to move together with measurable progress.

Concept diagram

CONVERGENCE DECISION FLOW

property bucket -> engine strategy -> helper invariants -> convergence audit -> closure

Metric graph

CONVERGENCE BURNDOWN

open hard properties    ███████
inconclusive aging      █████
closed with audit       ████████

Metrics and artifacts to collect

• engine effectiveness by property class

• induction and helper-lemma success ratio

• stalled-property aging dashboard

• runtime vs closure-quality movement

Mini case study

A stalled set closed only after case-splitting by mode and auditing fairness assumptions for realism.

Debug branches

• Bucket properties by structure and intent before tuning.

• Inspect proof core stability, not runtime alone.

• Reject speed gains that reduce legal reachability.

Senior review question

Ask: which requirement intent is proven, under which assumptions, and what residual risk remains?

Key takeaways

• Tie each proof claim to assumption boundaries and reachability evidence.

• Prefer minimal reversible fixes and preserve legal behavior visibility.

Common pitfalls

• Treating runtime reduction as proof-quality improvement without audits.

• Declaring closure while critical covers remain unreachable.

• Using broad waivers instead of first-divergence root-cause ownership.

Handoff explanation

Inputs should include assumptions, reset semantics, and property intent classes.

Outputs should include counterexample classification, closure confidence, and residual-risk labeling.