lib-db-gen

name	lib-db-gen
description	Generate Synopsys .db technology or stub libraries for early synthesis and link. Use when converting Liberty .lib to .db with lc_shell, or when creating a minimal black-box Liberty/.db from a Verilog top module port list.

Lib DB Gen

Use this skill when a flow needs a Synopsys .db and only has either a Liberty .lib or an RTL top module whose ports should become a black-box stub cell.

Commands

The bundled script is scripts/lib_db_gen.py.

Convert an existing Liberty file to DB:

python3 .agents/skills/lib-db-gen/scripts/lib_db_gen.py convert \
  --lib path/to/input.lib \
  --db path/to/output.db

Generate an early black-box Liberty from a Verilog top and compile it to DB:

python3 .agents/skills/lib-db-gen/scripts/lib_db_gen.py stub \
  --top-v path/to/top.v \
  --top top_module_name \
  --lib path/to/top_stub.lib \
  --db path/to/top_stub.db

Use --no-run to only emit the .lib and the Library Compiler Tcl script. Use --lc-shell /path/to/lc_shell when lc_shell is not on PATH. Use --work-dir <dir> to control Library Compiler's command file, lc_command.log, and lc_output.txt; by default this is <db-output-dir>/lc_work, not the repository root.

The generated <db-stem>.lc.tcl is temporary by default: remove it only after lc_shell produces a non-empty current-run .db that is atomically installed at the requested output path, and retain it when conversion fails or --no-run is selected. Use --keep-tcl to preserve a reusable final-output command file after a successful conversion. Use --tcl <path> only to override its location; cleanup semantics remain unchanged. Reject resolved-path collisions among Tcl, DB, Liberty, and Verilog inputs before writing any file.

Workflow

1. Prefer a real foundry or platform Liberty for timing signoff and mapped synthesis.
2. Use convert for real Liberty to .db conversion.
3. Use stub only for early integration, link, or black-box bring-up. The generated cell has ports and zero-area placeholder attributes; it is not timing or power evidence.
4. Keep generated .db, .lib, and LC logs out of Git unless they are reviewed release collateral.
5. For Design Compiler setup, point local ignored config such as scripts/local.mk at the generated .db, for example SKY130HD_DC_DB := /path/to/lib.db.

Notes

• stub parses ANSI-style module headers and simple non-ANSI declarations.
• Numeric packed ranges like [7:0] become Liberty bus types. Parameterized widths are treated as scalar with a warning; use a resolved wrapper if bus width fidelity matters.
• The generated stub DB is for black-box linking, not cell mapping. It does not replace a standard-cell target library.