ECO Regression Discipline: Reports & Metrics

Reports and metrics

Reports & Metrics for ECO Regression Discipline focuses on post-ECO regressions caught, corner coverage, signoff approval latency. The goal is to connect observed QoR movement to mechanism, ownership, and regression risk.

A report is useful only when it supports decisions. For ECO Regression Discipline, read metric movement with baseline context and expected budget.

Metric movement

QOR TREND — ECO Regression Discipline

metric quality
  ^
  |                      target band
  |                o  o  o
  |            o
  |      o  regression
  +----------------------------------> synthesis iteration
   baseline    tuning     signoff-ready

Track: post-ECO regressions caught, corner coverage, signoff approval latency

• Track post-ECO regressions caught, corner coverage, signoff approval latency with exact run manifests.

• Keep timing/area/power side-by-side in review dashboards.

• Require one-sentence mechanism hypothesis for every major delta.

• Store before/after artifacts with owner signoff.

Synthesis deep dive

Incremental and ECO synthesis protect schedule only with strict regression discipline.

Concept diagram

INCREMENTAL ECO LOOP

identify delta -> localized compile -> patch -> regression -> release

Metric graph

ECO CYCLE TIME

full compile      ███████████
incremental       █████

Reports and artifacts

• incremental reuse

• ECO patch list

• LEC status

• regression matrix

Mini case study

Localized compile cut turnaround 40%, but skipped LEC caused rollback.

Debug branches

• Reuse ratio is not enough

• Patch locality check

• Always include equivalence hooks

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.

Report reading lens