sim-tool-profiles

name	sim-tool-profiles
description	Internal reference: sim tool profiles (agent-loaded; do not invoke).
user-invocable	false

Simulation Tool Profiles

Common Contract

• Prefer wrapper: scripts/run_sim.sh
• Every run must emit:
  • primary log path
  • replay script path
  • pass/fail summary

Open-Source Baseline

• verilator:
  • scripts/run_sim.sh --sim verilator --top <tb_top> -f rtl/filelist_top.f --outdir sim/reports --trace
• iverilog:
  • scripts/run_sim.sh --sim iverilog --top <tb_top> -f rtl/filelist_top.f --outdir sim/reports

Commercial Profiles

• vcs:
  • scripts/run_sim.sh --sim vcs --top <tb_top> -f rtl/filelist_top.f --outdir sim/reports
• xrun:
  • scripts/run_sim.sh --sim xrun --top <tb_top> -f rtl/filelist_top.f --outdir sim/reports
• questa:
  • scripts/run_sim.sh --sim questa --top <tb_top> -f rtl/filelist_top.f --outdir sim/reports

Invocation Reference

The exact binaries and switches run_sim.sh uses per simulator. These are the shapes each vendor documents; changing them silently breaks the stage.

Simulator	Compile	Elaborate	Run
verilator	verilator --binary (or --cc)	—	generated executable
iverilog	iverilog -g2012	—	vvp
vcs	vcs -full64 -sverilog +v2k -o <exe>	(compile produces simv)	<exe>
xrun	xrun -compile -sv -xmlibdirname <lib>	xrun -elaborate -sv -xmlibdirname <lib> -top <tb>	xrun -R -xmlibdirname <lib>
questa	vlib work + vlog -sv -work work	vopt +acc -work work <tb> -o <tb>_opt	vsim -c -work work <tb>_opt -do "..."

Xcelium gotcha: -compile only parses and analyses — it does not write a snapshot. -R reinvokes an existing snapshot without recompiling or re-elaborating, so the -elaborate step is what makes -R work at all. All three steps must name the same -xmlibdirname.

UVM Coverage Collection (Commercial Only)

Code coverage must be enabled at both compile and runtime for all commercial simulators.

Simulator	Compile Flag	Runtime Flag	Coverage DB	Merge Tool
VCS	-cm line+cond+fsm+tgl+branch	-cm line+cond+fsm+tgl+branch -cm_dir <dir>.vdb	.vdb directory	urg -dir *.vdb -format both
Xcelium	-coverage all	-coverage all -covworkdir <dir>/cov_work -covscope tb_top	cov_work/ directory	imc -exec merge.tcl
Questa	+cover=bcestf (at vlog)	-coverage (at vsim) + -do "coverage save -onexit <file>.ucdb"	.ucdb file	vcover merge out.ucdb *.ucdb

Questa gotcha: +cover=bcestf at vlog compile is mandatory — runtime -coverage alone collects nothing.

UVM regression runner: {plugin_root}/skills/rtl-p5s-uvm-verify/scripts/run_regression_uvm.sh ({plugin_root} = plugin root from .rat/state/spawn-context.json)

• Handles compile-once + parallel multi-seed execution + coverage merge per simulator
• Targets: line ≥ 90%, toggle ≥ 80%, FSM ≥ 70%, branch ≥ 80%, functional ≥ 95%

Normalized Result Fields

• tool
• status (pass or fail)
• errors_count
• warnings_count
• log_path
• replay_path