Verilator is no longer used (all verification is via Vivado XSIM). Remove:
- 10 per-module tb_*.cpp Verilator testbenches
- the entire test_framework/ Verilator harness (lib/, run_all.py, config.json,
per-module test_plan.json/gen_vectors.py, golden vectors, reports)
- stale specs: verilator-conventions.md, test_framework/structure.md
(index.md updated to drop the Verilator entry)
Parallelize run_tb.sh K x case execution (modules stay serial):
- new run_xsim_jobs helper: compile+elaborate once (serial, populates the
shared xsim.dir), then run each (K,case) xsim in its own private workdir
with a COPY of xsim.dir (~1MB) so concurrent same-snapshot runs don't clobber
each other's runtime logs. Each workdir symlinks the repo sync_rtl tree so
the TB's repo-relative $readmemh vector paths resolve.
- top/enc/dec runners refactored to build a (snapshot:K:case) spec list and
hand it to run_xsim_jobs; ordered PASS/FAIL summary + per-job /tmp logs
preserved. Bare './run_tb.sh top' now also takes the parallel path.
Speedup (20 cores): top full sweep 2:11 -> 0:51 (~2.6x), ~320% CPU.
Verified: top (11) / enc (9) / dec (9) all PASS; missing-vector runs still
fail (file-not-found guard -> exit 1).
