vivado-log-analyzer

name

vivado-log-analyzer

description

Use when a Vivado synthesis or implementation run fails, or when the user asks "why did the build fail / what's wrong with this vivado log". Surfaces only the actionable error/critical-warning lines from large Vivado outputs (vivado.log, synth_1/runme.log, impl_1/runme.log, *.rpt) so the diagnosis fits in context. Trigger when the user shares a Vivado log path, mentions "synthesis failed", "implementation failed", "timing failure", "BRAM exhausted", or pastes raw Vivado output.

Vivado Log Analyzer

When to invoke

• A Vivado build (synth / impl / bitstream) failed and the user wants the cause.
• The user pastes or points at one of: vivado.log, *.runs/synth_1/runme.log, *.runs/impl_1/runme.log, *_timing_summary.rpt, *_utilization_*.rpt, *_drc_*.rpt.
• Auto-trigger when a tool result contains ERROR: [Synth, CRITICAL WARNING: [Place, Timing constraint not met, or similar Vivado markers.

What it does

Vivado logs are usually 5–50 MB and 95% noise. This skill runs scripts/analyze.py <log-path> which extracts only:

• ERROR: and CRITICAL WARNING: lines (Vivado's "this is why it failed").
• Timing summary endpoints with negative slack.
• Resource utilization rows above 95% (BRAM, LUT, DSP, URAM exhaustion).
• DRC violations (UCIO-1, LUTLP-1, NSTD-1, etc.).
• IP licensing failures (ERROR: [Common 17-69]).
• Missing constraint file errors.

It groups by failure category and prints at most ~80 lines so you can hand the result to the user or reason about it without burning context.

How to use

python3 .claude/skills/vivado-log-analyzer/scripts/analyze.py <path-to-log>

<path-to-log> can be any of:

• A single .log or .rpt file
• A Vivado project's *.runs/ directory (script will walk it)
• A build output directory (output/build/...)

If the user hasn't given a path, look first in output/, then in build/, then in any *.runs/synth_1/ or *.runs/impl_1/ directory.

After analysis

1. Print the categorized summary the script produced.
2. Do not re-read the raw log unless the summary is empty or the user asks for a specific line context. Re-reading defeats the purpose of the skill.
3. If timing is the failure category, point the user at src/templating/timing_constraints/ and any board-specific .xdc files.
4. If resource exhaustion is the failure category, the fix is almost always in src/templates/sv/ (template bloat) or in board selection (src/file_management/board_discovery.py — wrong FPGA part).
5. If IP licensing or "missing IP" errors appear, check the Containerfile and confirm the build is using a licensed Vivado image.

Anti-patterns

• Do not paste the raw Vivado log back to the user. They already have it.
• Do not run this on logs smaller than ~500 lines — just read them directly.
• Do not try to "fix" timing failures by widening constraints without understanding the constraint origin (src/templating/timing_constraints/ generates them; constraints are tied to donor profile).