Detailed parasitic import

RCLI-REQ-0070: import --spef FILE --spef-corner NAME requires a committed netlist (or one imported in the same transaction), a library for NAME, and the usual exclusive lock and base revision. A PARASIT v1 rbin (written before RCLI-REQ-0075) stores the immutable source in section 1 and UTF-8 JSON {corner, limits} metadata in section 2; readers keep accepting it. Record source identity. The table depends on netlist; import invalidates sta and sta_check even when a previous timing table predates parasitics. RCLI-REQ-0071: The shared SPEF reader supports detailed D_NET, NAME_MAP, connections, ground and inter-net coupling C, scalar R, explicit NS/PS, PF/FF, OHM/KOHM units, divider/delimiter/bus delimiters and escaped names. Values must be finite and nonnegative; errors are T0071 (syntax), T0072 (budget), T0073 (unsupported semantics). Reject reduced nets, inductance, triplets, pin-load attributes, included pin capacitances, duplicate identifiers and unresolved names. Metadata such as coordinates and date do not affect extracted RC. RCLI-REQ-0072: Limits are configurable and stored: defaults 32 MiB source, 100k nets, 500k nodes/name-map entries, 1M elements and 16 MiB names, with an absolute ceiling of eight times each default. Names have 4096-byte and lines 65536-byte caps. No unbounded enumeration or recursion. Ground coupling at factor one on each net's local endpoint; T0074 warns that crosstalk is absent. Require declared total C to agree with records within max(1e-8 pF, 1e-4 relative).

CLI budgets: --max-spef-mib, --max-rc-nets, --max-rc-nodes, --max-rc-elements, --max-rc-name-mib. Missing SPEF never causes these budgets or extraction modes to be implicitly enabled. A timing consumer must bind the connections and check complete annotation; it must not replace missing RC with estimated/ideal wires. A consumer asking for a corner without a source must fail explicitly.

RCLI-REQ-0075: --spef FILE --spef-corner NAME is repeatable and pairs in order; unequal counts, a corner given twice, more than 64 corners or a corner without a library are rejected before anything is read. The parasitics table is a PARASIT v2 rbin: section 1 is UTF-8 JSON {corners: [{corner, limits, source_path, source_hash}]} in ascending corner order (at most 256 KiB), and section i + 2 is the canonical decoded source of entry i. The corners of the base revision's table (v1 or v2) whose netlist is the netlist of the new revision are kept, an imported corner replaces its old source, and the source identity of every corner is recorded. Metrics name spef_corners, spef_kept_corners and per imported corner spef_imported (nets, nodes, elements, compression, byte counts); a one-file import also keeps the flat spef_* metrics. The decoded sources of all corners of the new table, kept and imported, which the import holds at once, total at most eight times the per-file byte budget (--max-spef-mib); more is rejected with T0072 and nothing is committed. The import drops sta, sta_check and limits.

RCLI-REQ-0076: An import that drops the parasitics table of its base revision (its netlist changed, so the table's upstream no longer holds) warns with one T0140 that names the dropped corners, the reason and the new revision: its timing has no extracted parasitics until SPEF is imported again, and a timing command that requires them (--require-wire-model spef_rc) rejects it. The dropped list of the envelope names the table as before. An import that replaces or keeps the table does not warn.

RCLI-REQ-0073: Accept plain UTF-8 and gzip SPEF, detected by magic bytes. Both encoded and decoded inputs obey --max-spef-mib; validate gzip CRC and concatenated members. Store canonical decoded source in PARASIT section 1, while source identity describes the original file. Report compression and encoded/decoded byte counts. Reject symlinks, FIFOs and devices before reading; Unix opens are nonblocking and do not follow symlinks. Failures preserve HEAD. RCLI-REQ-0074: Public in-memory parasitic objects must validate actual node counts, finite nonnegative values, names, indices and totals before a timing consumer indexes them. A forged serialized counter cannot reduce the memory estimate below actual stored vectors.

The parser estimates <512 MiB extra peak state at default limits (two 32 MiB source copies, <64 MiB names, 80 MiB nodes/index, 64 MiB elements and <80 MiB CSR/tree temporaries). A consumer adds its own corner/pin/tag state and accounts for worker concurrency. The source and all parse results are independent of GUI and Python. IEEE 1481-1999 defines the exchanged detailed parasitic format.

Compressed input does not increase these caps: retain at most 32 MiB encoded and 32 MiB decoded data plus a bounded decoder window. Small gzip/CRC/bomb tests use <4 MiB each and two test workers. A byte cap applies before token and graph budgets. No external decompressor or background process is required.