CHAPTER 16

Final implementation handoff

Handoff is the point where the implementation database stops being a working session and becomes a set of files that other teams and tools read. Those readers cannot ask the session a question. This chapter freezes the database, reruns the closure checks on it, writes the deliverables, checks what can be checked about the written files, and records what is still open and where signoff starts.

16.1 Stage purpose

By this stage each earlier chapter has produced its own evidence. Handoff adds three questions that no earlier chapter asks. Do the files you hand over describe the same database? Is that database the one whose checks you read? And who owns every result that is still open? A design can pass every stage and still fail here, because a file was written before the last change, or because a waiver lives in an email.

Each deliverable keeps a different part of the design, as the figure below shows for one small routed region. The stream file keeps shapes. The DEF file keeps cells and routing. The SPEF file keeps resistance and capacitance per net. The netlist keeps connectivity. A LEF abstract keeps the pins and the obstructions of a block and hides the inside. No single file is the design, so the set of files, written from one database, is the handoff.

Figure 24. One routed region as five deliverables keep it

Read it. Net n1 runs from U1 to U2 on M2 and M3. The GDS panel and the DEF panel share the same coordinates. GDS draws every shape, including the cell internals once the cell stream files are merged in, the filler cells and the metal fill. DEF draws the cells as names and outlines and keeps the routing. The SPEF panel replaces the geometry with three resistors and three capacitors on the same net. The netlist panel has two lines of text and no geometry at all. The LEF panel treats the region as a block, so only the pins a and y and a hatched obstruction remain. The ledger lists what each file cannot tell its reader.

Four words are used with fixed meanings in this chapter and the checklist. They are easy to mix up, and mixing them is how an incomplete handoff is called a finished one.

Word	Meaning here	Example
Tool completion	The command returned without an error.	streamOut finished and a file exists.
Analysis coverage	The analysis saw everything it should have seen.	Every required view and every net was included.
Stage qualification	The result meets the project budget, with its evidence kept.	Final DRC, connectivity and timing are clean on the frozen database.
Signoff	An independent tool, with its own rules and extraction, accepts the files.	A signoff physical verification run on the stream file.

This chapter reaches stage qualification. It does not reach signoff, and the last section says where the line is.

Four terms are used throughout. The freeze is the moment after which no command changes the database. A deliverable is a file written from the frozen database for a named consumer. The manifest is the table that records every deliverable with its source, time and check. The open-issues log records every accepted deviation, with an owner and a reason.

16.2 Entry prerequisites

Must already be true	Why
Chapters 1 to 15 passed, and the master checklist in Section 16.8 is filled in up to Chapter 15	This chapter repeats the closure checks. It does not replace the stage evidence.
No ECO is open	Chapter 15 requalifies every change. A change that arrives after the freeze starts a new freeze.
A handoff specification lists each deliverable, its format, its consumer and its naming rule	The manifest is checked against it. This book does not choose the list.
The layer map file for the stream, the macro stream files, and the DEF and LEF version settings are fixed	They decide what the written files contain. Chapter 13 reviewed the map file.
The output directory exists and has free space for the largest file	A stream file of a full block can be large, and a truncated file is easy to miss.
Project budgets for timing, DRC, connectivity and antenna exist	The reruns compare against them. This book sets no numbers.

16.3 Relevant files and analysis context

The order of work matters more here than in any other chapter. Every file is written from the database in the session, so a command that changes the database between two writes gives you two files that disagree. The order is: freeze and record, rerun the closure checks, save and prove the restore, write the files, read back what can be read back, then close the manifest.

The manifest below lists the usual deliverables. Which of them your project needs comes from the handoff specification. The saved database carries the constraints. saveDesign keeps a link to each original SDC file when the file was not modified, and copies it into the saved directory when it was modified. The -tcon option copies every SDC file, which makes the save independent of the original location. Derates and analysis-mode settings are not carried by an SDC file, so keep the record of Chapter 14, card X-07. Constraints that must travel as a stand-alone file are written per view with writeTimingCon, which uses Design Compiler format. Whether the consumer accepts that file unchanged belongs in the handoff specification.

Deliverable	Written by	Consumer	Checked by
Saved database, with constraints	`saveDesign`	Any later Innovus session	Z-04
Verilog netlist, logical or with PG	`saveNetlist`	Equivalence check, signoff timing, simulation	Z-05
DEF file with routing	`defOut`	Extraction and physical tools	Z-06
Stream file, GDSII or OASIS	`streamOut`	Signoff physical verification	Z-07
SPEF, one per RC corner	`rcOut`	Signoff timing	Z-08
Timing constraints, one per view	`writeTimingCon`	Signoff timing, simulation	Z-08
SDF, for the view pairs required	`write_sdf`	Simulation and signoff timing	Z-08
Summary and gate count reports	`summaryReport`, `reportGateCount`	Review	Z-01
Closure and timing reports	Cards Z-02 and Z-03	Review and signoff	Z-02, Z-03
Block LEF abstract and model	`write_lef_abstract`, `saveModel`	A parent design. Only if the block is used inside one.	Not applicable to a top-level block
Manifest, open-issues log, log files	You, from the cards	Everyone	Z-01

Every deliverable carries one of three evidence classes, and the class decides what you may claim about it. The classes are used in every chapter, and they are collected here because the handoff is where they meet.

Class	What it is	What you may claim
Preliminary	An estimate made before the final data exists, such as an early route or pre-CTS timing with ideal clocks.	A direction. Never a pass.
Implementation	A result computed by the implementation tool on the database as it stood at that stage, such as DRC, connectivity and post-route timing. This chapter repeats them on the frozen database.	The stage is qualified, against the project budget.
Signoff	A result from an independent tool, with its own rule decks and extraction, run on the written files.	The design is accepted for the next step. This book does not produce it.

The settings that shape the written files are part of the evidence. getExportMode and getStreamOutMode return the netlist and stream settings, and the lefDefOutVersion, defOutLefVia and defOutLefNDR globals control the DEF and LEF output. Record all of them in the manifest, because a file written with a different setting is a different file.

16.3.1 Where the signoff boundary lies

Figure 25. Where the evidence of this book ends and signoff begins

Read it. The left frame is the Innovus session, which produces preliminary and implementation evidence. The middle frame is the four groups of files written for handoff. The right frame is four consumers that sit outside this book: physical verification, equivalence checking, timing signoff and the release review. The red dashed line is the boundary. Every arrow that crosses it hands over files and nothing else.

Four rules keep the boundary honest. Do not call the handoff signed off. Do not copy a number from an Innovus report into a signoff column. Keep the open issues that wait for signoff in the log, marked as deferred, so that the signoff result can close them by name. And hand over the manifest with the files, because it is the only record of which database the files came from.

16.4 Checks and command cards

The cards follow the order of work. Three come before the save, one saves, and four write and check the files. Each card says what to rerun if it fails, and the answer is always the same in kind: go back to the chapter that owns the defect, then start the handoff again from card Z-01. In this chapter, clean means no violation without an owner and a decision.

16.4.1 Pre-stage checks

The freeze starts with identity and inventory. Neither changes the database, and both are cheap, so run them before the long checks. If either fails, the long checks would be run on the wrong design.

Z-01Run identity and final summary

Question it answers	Is this the release, the settings and the message record that the project approved, and what exactly is in the database that will be handed off?
Stage	Freeze
Product	Innovus Implementation. The reference entry names no separate licence requirement for this command.
Required state	The last ECO or fix is done. The session holds the design that will be handed off.
Legacy UI	getVersion report_message -errors -count report_message -suppressed report_message -warnings -count getLogFileName -fullPath report_command_mode -non_default summaryReport -noHtml -outfile <f> reportGateCount -stdCellOnly -outfile <f> report_area -out_file <f>

Common UI	Not yet verified No Common UI form is printed. The provided files do not document one.
Mapping	Not established in the provided documentation
Options used	`-fullPath` with getLogFileName, returns the absolute path of the log file. `-errors -count` with report_message, returns a Tcl list of {ID count} pairs for every error ID. `-suppressed` with report_message, lists the suppressed message IDs. `-non_default` with report_command_mode, lists every mode option whose value is not the default. `-noHtml, -outfile` with summaryReport, write the text version only to a named file. -outfile needs -noHtml. `-stdCellOnly, -outfile` with reportGateCount, count standard cells only and name the output file. `-out_file` with report_area, writes the area of each module and of the top level.
Scope and view	The session and the whole design.
Why keep the summary	The summary is the file you compare after the restore in Z-04. The gate count and the area by module are what reviewers ask for first, and they are cheap to write now and hard to reproduce later.
Effect on session	writes files. Some commands in this card only read or report.
Output	Version, path, message lists and a mode listing on the console, and two text files with the design summary and the gate count.
Fields that matter	The release and build, the log path, the error and suppressed lists, the non-default modes, Design Status, instance and macro counts, and the gate count.
Healthy	Release as approved, no error ID, Routed, expected counts.
Warning	A new warning ID, or a count change only partly explained.
Hard stop	An error ID, a new suppressed ID, or not Routed.
Common misuse	Reading an empty error list as proof of a clean flow, since it counts this session only. Or comparing a gate count with an instance count: the gate count is module area divided by an assumed gate size.
Root cause and fix	Find the first command that issued the ID in the log, correct it, and rerun from the stage that owns it.
Rerun after a fix	Rerun Z-01 after the last change, then every later card.
Verification	Legacy syntax checked against the Innovus Legacy text reference.

16.4.2 Post-stage checks

The placement, DRC, connectivity, antenna, filler and timing checks of Chapters 7 and 11 to 13 are repeated on the frozen database. Density and via-count reports are repeated only if the database changed after them; record which. This is not duplication. A result from an earlier stage describes the database of that stage, and the handoff needs results that describe this one.

Z-02Physical closure on the frozen database

Question it answers	Is the frozen database placed legally, free of DRC violations, fully connected and free of antenna violations?
Stage	Before the save
Product	Innovus Implementation. The reference entry names no separate licence requirement for this command.
Required state	Z-01 is done. No command that changes the database has run since.
Legacy UI	checkPlace <report_file> checkFiller -file <f> verify_drc -limit 0 -report <f> verifyConnectivity -type regular -report <f> verifyConnectivity -type special -report <f> verify_antenna -report <f>

Common UI	Not yet verified No Common UI form is printed. The provided files do not document one.
Mapping	Not established in the provided documentation
Options used	`violationReportFileName` with checkPlace, names the detailed report. `-limit` with verify_drc, caps the number of reported violations. The default cap is 1000, and 0 removes it. `-type` with verifyConnectivity, selects regular or special wires. `-report` writes the report file.
Scope and view	Whole design for every check. No area restriction.
Order	checkPlace runs first because verify_drc checks only placed instances. An unplaced cell would be invisible to the DRC run.
Effect on session	adds GUI violation markers; writes files; runs an expensive analysis
Output	Violation markers and report files.
Fields that matter	The Unplaced count and placement violations, filler gaps, DRC violations by rule, opens, shorts and unrouted nets on regular and special nets, and antenna violations by net.
Healthy	Nothing unplaced, no DRC, open, short, antenna or unapproved filler gap.
Warning	A cap or option hides a category.
Hard stop	Any such violation without an owner and a decision.
Common misuse	Reading the cap as the count, or handing off an area run. The first hides violations, and the second misses damage outside the box.
Root cause and fix	Fix the defect in the chapter that owns it, using the rerun matrix of Chapter 15.
Rerun after a fix	Rerun Z-02 and every later card.
Verification	Legacy syntax checked against the Innovus Legacy text reference.

Z-03Timing on the frozen database

Question it answers	Do the required views meet the project budget on the frozen database, with parasitics on every net?
Stage	Before the save
Product	Innovus Implementation. The reference entry names no separate licence requirement for this command.
Required state	Z-02 is clean. The analysis views are active as in the baseline.
Legacy UI	check_timing -verbose timeDesign -postRoute -outDir <dir> -prefix <prefix> report_annotated_parasitics -list_not_annotated timeDesign -postRoute -hold -outDir <dir> -prefix <prefix>

Common UI	Not yet verified No Common UI form is printed. The provided files do not document one.
Mapping	Not established in the provided documentation
Options used	`-verbose` with check_timing, lists the warnings in detail, grouped by type. Without it only a count per type is printed. `-postRoute` with timeDesign, runs native detailed extraction and timing analysis, and sets the analysis mode to -clkSrcPath true and -clockPropagation sdcControl. `-hold` with timeDesign, reports hold violations only. `-outDir, -prefix` name the report directory and the file prefix. `-list_not_annotated` with report_annotated_parasitics, lists the nets that have no annotated parasitics.
Scope and view	Every active view, setup and hold.
Cost	timeDesign -postRoute runs extraction and analysis, so it is the slowest card of the chapter before the writes.
Effect on session	changes analysis configuration; updates the design database; writes files; runs an expensive analysis. Some commands in this card only read or report.
Output	Timing reports by view and path group, a DRV report, and the parasitic annotation summary.
Fields that matter	WNS, TNS and violating paths per view and path group, for setup and for hold. Maximum transition, capacitance and fanout violations. The not-annotated nets.
Healthy	Setup and hold meet budget in every required view, every net annotated.
Warning	Options or directory differ from the baseline run.
Hard stop	A required view misses the project budget, or a net has no annotated parasitics.
Common misuse	Using the timing reports of Chapter 12 as final. They describe the database of that stage, not this one.
Root cause and fix	Fix the cause in Chapter 12 or Chapter 14, then rerun Z-02 and Z-03.
Rerun after a fix	Rerun Z-03 in every view.
Verification	Legacy syntax checked against the Innovus Legacy text reference.

Z-04Save and restore proof

Question it answers	Does the saved database restore to the same design that was frozen?
Stage	Save
Product	Innovus Implementation. The reference entry names no separate licence requirement for this command.
Required state	Z-01 to Z-03 are clean. Nothing has changed the database since Z-02 started. The restore runs in a new session, and Z-05 to Z-08 are written in the frozen session.
Legacy UI	saveDesign <final>.enc -tcon -rc restoreDesign <final>.enc.dat <top>

Common UI	`write_db <dir>` Verified write_db appears in the RAK lab in a synthesis flow only, as in Chapter 1. The lab does not show it for a routed design, and its equivalence to saveDesign is not verified.
Mapping	different command name, equivalence of saved content not verified
Options used	`-tcon` with saveDesign, copies every SDC file into the saved directory, even an unmodified one. `-rc` with saveDesign, saves the RC extraction data. Nothing is saved if the design is not extracted or the preRoute engine was used.
Scope and view	The whole database. The saved directory is read as a whole.
What the proof covers	The summary shows status and counts only, not constraints, routing or parasitics. Compare report_command_mode -non_default from Z-01, and the settings record of Chapter 14 (X-07), in the restored session, and rely on Z-06 for routing. saveDesign -tgz and -libs make portable copies, and the manifest says which was used.
Effect on session	updates the design database; writes files
Output	A restore file, a .dat directory, and in the new session a restored design and a second summary written with the Z-01 command.
Fields that matter	Restore messages, and the Design Status and counts of the summary of the restored design, which you compare with the summary of Z-01.
Healthy	No restore error, and the summary equals the frozen one.
Warning	The restore needed a file from outside the saved directory.
Hard stop	The restore errors, or the summaries differ.
Common misuse	Saving over an earlier handoff save, or editing the saved directory afterwards. The reference says a save in an existing location overwrites it, and a modified directory can corrupt later restores.
Root cause and fix	Save to a new name, never edit the directory, and repeat the restore test.
Rerun after a fix	Rerun Z-04, then the write cards.
Verification	Legacy syntax checked against the Innovus Legacy text reference.

Z-05Netlist export

Question it answers	Is the exported netlist the logic of the frozen design, in the form the consumer needs?
Stage	Write
Product	Innovus Implementation. The reference entry names no separate licence requirement for this command.
Required state	Z-04 is done, the frozen session is still open, and nothing has changed the database since.
Legacy UI	check_design -type assign_statements -out_file <f> getExportMode saveNetlist <final>.v saveNetlist <final_pg>.v -includePowerGround

Common UI	`write_netlist <file>` Verified write_netlist appears in the RAK lab in a synthesis flow only. The lab does not show it for a routed design, and its option equivalence is not verified.
Mapping	different command name, option equivalence not verified
Options used	`-type assign_statements` with check_design, checks the netlist for assign statements before it is exported. `-out_file` with check_design, writes the full list of findings. `-includePowerGround` with saveNetlist, adds physical-only PG nets and PG ports. The reference notes that some LVS flows prefer them explicit.
Scope and view	Whole design.
Logical or physical	By default the netlist is logical, and hierarchical only if the loaded netlist was. Filler and other physical instances appear only when asked for with -includePhysicalInst. By default constants on assign nets and ports are written as 1'b0 and 1'b1, which tools outside Innovus may not handle; -replaceTieConnection writes undriven nets instead. The consumer decides which form it needs, and the manifest records it.
Effect on session	writes files. Some commands in this card only read or report.
Output	A findings file, a settings listing and one or two Verilog files.
Fields that matter	The assign statement findings, the export settings and their source, and the size and time of each file.
Healthy	No assign statement, settings recorded, file after the save.
Warning	A setting differs from default without a reason.
Hard stop	check_design reports an error, or a needed PG port is missing.
Common misuse	Reading a netlist written with physical cells back into Innovus. The reference says the -includePhysicalCell form should not be read back.
Root cause and fix	Fix the netlist cause in the chapter that owns it, rewrite after a new freeze.
Rerun after a fix	Rerun Z-05.
Verification	Legacy syntax checked against the Innovus Legacy text reference.

Z-06DEF export and comparison

Question it answers	Does the DEF file carry the placement and the routing of the frozen design, and does it agree with the database?
Stage	Write
Product	Innovus Implementation. The reference entry names no separate licence requirement for this command.
Required state	Z-04 is done, in the frozen session. The DEF version globals are set and recorded.
Legacy UI	defOut -routing <final>.def defComp <final>.def -reportFile <f>

Common UI	Not yet verified No Common UI form is printed. The provided files do not document one.
Mapping	Not established in the provided documentation
Options used	`-routing` with defOut, adds the routing to the NETS section. It implies -netlist, and without it no vias are written. `-reportFile` with defComp, names the comparison report. The default is defPhyDiff.rpt.
Scope and view	Whole design.
Version and vias	The lefDefOutVersion global selects the DEF version. LEF vias and nondefault rules are written only when defOutLefVia and defOutLefNDR are 1. Record all three values. By default defComp does not compare placement blockages or halos; -placeBlockage adds them.
Effect on session	writes files
Output	A DEF file and a comparison report.
Fields that matter	ADDINST, DELINST, CHANGECELL and MOVEINST lines, ADDNET and DELNET lines, CHANGEROUTE and POWERROUTE blocks, and the CHANGEAREA box.
Healthy	No differences, so the file and the database agree here.
Warning	A few differences, each in the manifest.
Hard stop	Added, deleted or moved instances, or changed routes.
Common misuse	Writing the DEF without -routing and treating it as the routed design. The vias are missing from such a file. Or reading a clean defComp as proof that a consumer can load the file.
Root cause and fix	Rewrite with the settings the consumer needs, and compare again.
Rerun after a fix	Rerun Z-06.
Verification	Legacy syntax checked against the Innovus Legacy text reference.

Z-07Stream file

Question it answers	Is the stream file written from the frozen database with the approved map, units and macro files, and with its log read?
Stage	Write
Product	Innovus Implementation. The reference entry names no separate licence requirement for this command.
Required state	Z-04 is done, in the frozen session. The map file and the stream files to merge, for standard cells, I/O cells and macros, are the approved versions.
Legacy UI	setStreamOutMode -check_map_file true streamOut <final>.gds -mapFile <map> -units <n> -merge {<gds_files>} -reportFile <f> getStreamOutMode

Common UI	Not yet verified No Common UI form is printed. The provided files do not document one.
Mapping	Not established in the provided documentation
Options used	`-check_map_file true` with setStreamOutMode, prints the design objects that the map file does not map in the log. Only the main objects are checked. `-mapFile` names the layer map. Layers absent from the file are not written. `-units` sets the resolution of values in the file. The library name defaults to DesignLib, and -libName changes it. `-reportFile` writes the cells whose names were changed. It is not a general run report. `-merge` merges external stream files and warns when a cell name changes.
Scope and view	Whole database. No area options are used.
Relation to Chapter 13	Chapter 13 qualified the map file, the fill layers and the log of a stream written after fill. This card repeats the write on the frozen database and records what was written. The tool has no read-back for the stream file, so only the signoff tools verify it.
Effect on session	changes analysis configuration; writes files. Some commands in this card only read or report.
Output	A stream file, and a list of the changed cell names.
Fields that matter	The settings listing, log messages about unmapped objects, the cell names changed during the merge, and the size and time of the file.
Healthy	No unmapped object or unexplained rename, file after the save.
Warning	A merged cell name changed and the manifest does not say so.
Hard stop	Required layers unmapped, or the merge failed.
Common misuse	Letting the tool create a generic map file. The reference says such a file must be customised, and layers it does not list are not written.
Root cause and fix	Correct the map or the merge list, and write again.
Rerun after a fix	Rerun Z-07.
Verification	Legacy syntax checked against the Innovus Legacy text reference.

Z-08Parasitics, delay and constraint files

Question it answers	Is there one SPEF per required RC corner, one SDF per required pair of views and one constraints file per view, written from the frozen database?
Stage	Write
Product	Innovus Implementation. The reference entry names no separate licence requirement for this command.
Required state	Z-03 shows complete annotation. Extraction ran on the frozen database with the engine the project requires, and Z-04 is done. The files are written in the frozen session.
Legacy UI	rcOut -spef <final>.spef -rc_corner <rc> write_sdf <final>.sdf -recompute_delay_calc -min_view <v1> -max_view <v2> writeTimingCon <view>.sdc -view <view>

Common UI	Not yet verified No Common UI form is printed. The provided files do not document one.
Mapping	Not established in the provided documentation
Options used	`-spef, -rc_corner` with rcOut, name the output file and the RC corner. Name the file by corner, because -view picks the corner of a view and two views can share one. `-view` with writeTimingCon, names the view whose constraints are written. `-recompute_delay_calc` with write_sdf, recomputes the data needed for a complete SDF. Without it only delays already computed for timing are written. `-min_view, -max_view` with write_sdf, fill the min and max slots from the early and late delays of the named views.
Scope and view	One run per corner, view pair or view.
What the file does not say	A SPEF read-back, with spefIn and an annotation check, is defined in Chapter 14, cards X-04 and X-03. A SPEF holds parasitics, not slack. Whether the corner meets timing was decided in Z-03, and the signoff tool decides it again from the SPEF. write_sdf writes delays scaled by set_timing_derate unless -no_derate is given, so record that choice.
Effect on session	writes files; runs an expensive analysis
Output	SPEF, SDF and constraints files.
Fields that matter	The file names, the corner or view each one used, and the size and time of each file.
Healthy	A SPEF per corner, an SDF per view pair, a constraints file per view, all after the last change.
Warning	An SDF written without recomputed delays holds only cached delays.
Hard stop	A corner has no file, or a file or its extraction predates the last change.
Common misuse	Writing one SPEF and using it for every corner, or taking an old file because its name matches.
Root cause and fix	Run the missing corner or pair, and put the corner in the file name.
Rerun after a fix	Rerun Z-08 for every corner after any database change.
Verification	Legacy syntax checked against the Innovus Legacy text reference.

16.5 Required reports, artefacts and how to read them

Report or artefact	Fields that support qualification	Evidence class
Identity listing, summary and gate count (Z-01)	release, log path, message lists, Design Status, counts, gate count	implementation
Closure reports (Z-02)	Unplaced count, DRC, opens and shorts, antenna	implementation
Timing and annotation (Z-03)	WNS and TNS per view and group, DRVs, not-annotated nets	implementation
Restore summary (Z-04)	Design Status and counts after the restore	implementation
Netlist, DEF, stream, SPEF, SDF (Z-05 to Z-08)	name, size, write time, source session, settings	implementation
Signoff reports on those files	owned by the signoff tools	signoff

The manifest is the report of this chapter. Its job is to show that every file is newer than the last change to the database, and that SPEF, SDF and timing files come from an extraction made after it. The example below is SYNTHETIC and partial: it shows one SPEF and no SDF or constraints line. The times, sizes and names are invented, and the format is only a suggestion. Record a checksum with each size.

Reading a handoff manifestSynthetic report, not tool output

HANDOFF MANIFEST            ## illustrative excerpt
run id               blk_r07
last database change 13:58   ecoAddRepeater on net n_ctl_47
saved database       14:02   blk_final.enc.dat

file               written  size     corner/view   check
closure reports    13:44    -        all           Z-02 clean
timing reports     13:41    -        3 views       Z-03 clean
blk_final.spef     13:52    41 MB    rcworst       rcOut finished
blk_final.v        14:05    3 MB     -             assign check clean
blk_final.def      14:07    48 MB    -             defComp: no differences
blk_final.gds      14:31    210 MB   -             2 cell names changed in merge

Let us read it with one rule: a file is current only if it was written after the last change to the database. The last change is the buffer at 13:58. The netlist, the DEF file and the stream file were written after it, so they describe the final database. The closure reports, the timing reports and the SPEF were written before it, so they describe a database that no longer exists. The two merged cell names in the stream file are not an error, but they must be named in the manifest. The manifest is therefore not ready: three rows are stale, and the ECO that made them stale was not requalified.

The open-issues log is the second record. Every deviation that you accept goes into it, with an owner and an end condition. The tool never grants a waiver. A person does, and the log is where that person is named. The rows below are SYNTHETIC and only show the shape.

ID	Card	Finding	Class	Decision	Owner and end condition
OI-01	Z-02	DRC markers on a power via array, none on signal routing	implementation	Defer to signoff	Routing lead. Closed by the signoff DRC result.
OI-02	Z-03	Hold slack in one corner below budget by a small margin	implementation	Fix	Timing lead. Closed by an ECO and its Chapter 15 reruns.
OI-03	Z-07	Two merged cell names changed	implementation	Accept	Release owner. Names listed in the manifest.

16.6 Healthy, suspicious and hard-stop examples

Finding	Status	Why
Every file is newer than the last database change, and each has a check recorded	PASS	The files describe one database, and the manifest proves it.
A restored session gives the same summary as the frozen session	PASS	The saved database is a usable record of the design.
A merge renamed a cell and the manifest does not say so	WARN / REVIEW	The rename is probably harmless, but the consumer must know.
An SDF written without recomputed delays	WARN / REVIEW	It holds only cached delays, which may not suit general use.
A closure or timing report older than the last ECO	HARD STOP	The result describes a database that no longer exists.
A required corner has no SPEF	HARD STOP	Signoff timing cannot run for that corner.
Open issue with no owner or end condition	HARD STOP	An unowned deviation is not accepted, only forgotten.
Block LEF abstract for a top-level block	NOT APPLICABLE	No parent design uses the block.
Power-intent files in a single-supply block	NOT APPLICABLE	No power domains exist.

16.7 Debugging, corrective action and reruns

A failed handoff check has one of two causes. Either the database has a defect, or the files do not match the database. The first goes back to the chapter that owns the defect. The second is repaired by writing the file again. Both end in the same step, which is to start again from Z-01, because the handoff is only as good as its newest change.

Symptom	Likely cause	Action
Restore summary differs from the frozen summary	The database changed after the summary, or the saved directory was edited	Save to a new name from the frozen session and repeat Z-04.
A file is older than the save	It was written in an earlier session or before the last change	Rewrite it in the frozen session.
defComp lists differences	The DEF was written before a change, or with different options	Rewrite the DEF with the recorded settings and compare again.
Stream log lists unmapped layers	The map file does not cover a layer of the design	Correct the map file, as in Chapter 13, and write again.
check_design reports assign statements	The netlist has assign statements that the consumer cannot read	Remove them in the netlist source, or with remove_assigns where it can. That changes the database, so start a new freeze.
A file has the right name but the wrong corner	One run was reused for several corners	Put the corner in the file name and write one file per corner.

16.7.1 Worked example: files written around a late buffer

Take the manifest of Section 16.5. A hold buffer was added to net n_ctl_47 at 13:58, after the closure reports and the SPEF. The buffer is row B of the rerun matrix in Chapter 15, so it is a new freeze. The row asks for the detailed-route checks, the post-route timing and the extraction again, which are the three stale rows of the manifest.

The decision is HARD STOP for the closure reports, the timing reports and the SPEF. The netlist, the DEF file and the stream file were written after the change, from the database saved at 14:02, so they stay only if the reruns find nothing and the restore proof of Z-04 is repeated. Run Z-01 to Z-04 again, then write the SPEF with Z-08. The times and names here are invented. The rule is general: a deliverable is valid only for the database state it was written from.

16.8 Exit criteria and master checklist

The table is the one-page master checklist. A row is complete only when its evidence is stored with the manifest. PRE is preliminary evidence and IMPL is implementation evidence. No row is complete signoff evidence: the signoff-class items of Chapter 14 are comparisons, and the project decides how to count them.

Ch	Stage	Question that must be answered yes	Evidence held	Class
1	Tool and session S-01 to S-06	Do release, UI, settings, resources, licences and the one-restore provenance match the project baseline?	Version string, log path, message lists, mode listing, resource and licence records	IMPL
2	Design import I-01 to I-06	Is every instance bound, no net multiply driven, and the inventory as expected?	check_design, checkDesign and checkUnique reports, PG identity, inventory snapshot	PRE + IMPL
3	SDC and MMMC T-01 to T-07	Do views, clocks, modes, exceptions and coverage equal the methodology?	check_timing output, view list, coverage, baseline slack and DRVs	PRE + IMPL
4	Floorplan F-01 to F-07	Does the geometry match the specification, and does the floorplan leave routing room?	checkFPlan, checkPlace, pin check, TU and EU, early congestion, special-net baseline	PRE + IMPL
5	Power planning P-01 to P-08	Is the grid connected, via-complete and inside the track budget?	PG connectivity, power via and special-route reports, track table	PRE + IMPL
6	Pre-placement readiness R-01 to R-09	Were the placement prerequisites met before placement started?	Prerequisite check output, the settings that applied, saved checkpoint	PRE + IMPL
7	Placement L-01 to L-10	Is placement legal and uncongested, with pre-CTS timing reviewed?	checkPlace, density, congestion, pre-CTS timing	PRE + IMPL
8	CTS readiness K-01 to K-10	Is the clock specification complete and checked before CTS?	Clock specification, prerequisite check output	IMPL
9	CTS C-01 to C-09	Do the trees meet skew, DRV and timing budgets in every corner reported?	Clock tree reports, clock routes, post-CTS timing	PRE + IMPL
10	Global and early routing G-01 to G-09	Is routing resource sufficient before detailed routing starts?	Congestion and overflow reports, route setup and readiness records	PRE + IMPL
11	Detailed routing D-01 to D-10	Is routing complete, DRC clean and antenna clean, with a post-route baseline?	DRC, connectivity and antenna reports, timing baseline	PRE + IMPL
12	Post-route optimisation O-01 to O-09	Does timing meet the budget in every view without new violations?	timeDesign reports per view, DRC rerun, area and power	PRE + IMPL
13	Chip finishing H-01 to H-10	Are filler, metal fill and density qualified, and the stream reviewed?	Filler, fill, density and antenna reports, post-fill timing, stream log	IMPL, PRE if fill assumed
14	Extraction and correlation X-01 to X-08	Is every net annotated, and does extraction correlate within the budget?	Annotation report, SPEF per corner, factors, settings parity, correlation table	PRE + IMPL, SIGNOFF compared
15	ECO E-01 to E-08	Was every change since qualification requalified by the rerun matrix?	Manifest, defComp report, reruns named	IMPL
16	Handoff Z-01 to Z-08	Do all files come from one frozen database, with manifest and open issues?	Cards Z-01 to Z-08, manifest, open-issues log	IMPL

Handoff is ready when every row is complete, every file is newer than the last database change, and the open-issues log has an owner for every item. It is not signed off. Signoff starts on the far side of the boundary in Section 16.3.1, with tools and rule decks that are outside this book.

CHAPTER 16 SANITY CHECKS

16.9 Sanity check cheat sheet: Final handoff

One row per command card. Read left to right: the check, the command that answers it, then what a healthy result, a result to review and a hard stop look like. Judge every row against your project budgets, because this book sets no universal limits.

Card	Check and when	Command	Healthy	Review	Hard stop
Z-01	Run identity and final summary Freeze	`getVersion` `report_message -errors -count` `report_message -suppressed`	Release as approved, no error ID, Routed, expected counts.	A new warning ID, or a count change only partly explained.	An error ID, a new suppressed ID, or not Routed.
Z-02	Physical closure on the frozen database Before the save	`checkPlace <report_file>` `checkFiller -file <f>` `verify_drc -limit 0 -report <f>`	Nothing unplaced, no DRC, open, short, antenna or unapproved filler gap.	A cap or option hides a category.	Any such violation without an owner and a decision.
Z-03	Timing on the frozen database Before the save	`check_timing -verbose` `timeDesign -postRoute -outDir <dir> -prefix <prefix>` `report_annotated_parasitics -list_not_annotated`	Setup and hold meet budget in every required view, every net annotated.	Options or directory differ from the baseline run.	A required view misses the project budget, or a net has no annotated parasitics.
Z-04	Save and restore proof Save	`saveDesign <final>.enc -tcon -rc` `restoreDesign <final>.enc.dat <top>`	No restore error, and the summary equals the frozen one.	The restore needed a file from outside the saved directory.	The restore errors, or the summaries differ.
Z-05	Netlist export Write	`check_design -type assign_statements -out_file <f>` `getExportMode` `saveNetlist <final>.v`	No assign statement, settings recorded, file after the save.	A setting differs from default without a reason.	check_design reports an error, or a needed PG port is missing.
Z-06	DEF export and comparison Write	`defOut -routing <final>.def` `defComp <final>.def -reportFile <f>`	No differences, so the file and the database agree here.	A few differences, each in the manifest.	Added, deleted or moved instances, or changed routes.
Z-07	Stream file Write	`setStreamOutMode -check_map_file true` `streamOut <final>.gds -mapFile <map> -units <n> -merge {<gds_files>} -reportFile <f>` `getStreamOutMode`	No unmapped object or unexplained rename, file after the save.	A merged cell name changed and the manifest does not say so.	Required layers unmapped, or the merge failed.
Z-08	Parasitics, delay and constraint files Write	`rcOut -spef <final>.spef -rc_corner <rc>` `write_sdf <final>.sdf -recompute_delay_calc -min_view <v1> -max_view <v2>` `writeTimingCon <view>.sdc -view <view>`	A SPEF per corner, an SDF per view pair, a constraints file per view, all after the last change.	An SDF written without recomputed delays holds only cached delays.	A corner has no file, or a file or its extraction predates the last change.

CHAPTER 16 CHEAT SHEET

16.10 Command cheat sheet: Final handoff

Legacy UI commands. Angle brackets are placeholders, and values shown are examples, not project limits.

Command	What it produces

Run identity and messages
`getVersion`	The full release and build string. Record it in the handoff manifest.
`getLogFileName -fullPath`	The absolute path of the current log file, for the manifest.
`report_message -errors -count`	A Tcl list of {ID count} pairs for every error ID issued. An empty list means no errors were issued.
`report_message -warnings -count`	A Tcl list of {ID count} pairs for every warning ID issued, to compare with the baseline.
`report_message -suppressed`	The message IDs suppressed in this session. Suppressed IDs hide evidence, so compare the list with the baseline.
`report_command_mode -non_default`	Every *Mode option whose value differs from the default, for the manifest.
`getLicenseStatus`	A summary of every licence the session has checked out.
`report_resource -peak`	The peak memory used by the session so far.

Inventory and summaries
`summaryReport -noHtml -outfile <f>`	A text summary with Design Status, instance counts, and macro and standard-cell tables. Writes a file.
`reportGateCount -stdCellOnly -outfile <f>`	The gate count of standard cells only, written to a file whose default extension is .gateCount.
`report_area -out_file <f>`	The combined standard-cell area of each hierarchical module and of the top-level design. Writes a file.
`report_area -summary`	The area summary of the design as a whole. The reference calls it equivalent to -depth 0.

Closure checks rerun on the final database
`checkPlace <report_file>`	Placed, fixed and unplaced counts and placement violations by category. Adds markers and writes a file.
`verify_drc -limit 0 -report <f>`	DRC violations on placed instances with markers. The default cap is 1000 errors, and 0 removes the cap. Adds markers and writes a file.
`verify_drc -check_only special -report <f>`	DRC on special wiring only, for the power grid. Adds markers and writes a file.
`verifyConnectivity -type regular -report <f>`	Opens, unconnected wires and pins, loops and unrouted nets on regular nets. Adds markers and writes a file.
`verifyConnectivity -type special -report <f>`	The same check on special nets. Unconnected terminals are still reported unless -noUnConnPin is given.
`verify_antenna -report <f>`	Process antenna violations on routed nets. Default report name is <design>.antenna.rpt. Writes a file.
`verify_antenna -detailed -report <f>`	The antenna value of every layer of every net, including nets with no violation. Writes a file.
`check_design -type assign_statements -out_file <f>`	A check of the netlist for assign statements, meant to run before a netlist is exported for signoff. Writes a file.

Timing rerun on the final database
`check_timing -verbose`	Constraint consistency and completeness warnings, with detail.
`timeDesign -postRoute -outDir <dir> -prefix <prefix>`	Post-route extraction and setup timing reports in the output directory. Changes the analysis mode and the database. Runs long and writes files.
`timeDesign -postRoute -hold -outDir <dir> -prefix <prefix>`	The same for hold. Runs long and writes files.
`timeDesign -postRoute -expandedViews -outDir <dir>`	A separate report directory for every active view in a multi-mode multi-corner session. Runs long and writes files.
`report_annotated_parasitics -list_not_annotated`	The annotated parasitics summary by net type, and the nets that have no annotation.

Save and restore
`saveDesign <final>.enc`	A restore file and the .dat database directory. Saving to an existing location overwrites it. Writes files.
`saveDesign <final>.enc -tcon -rc`	The same, with every SDC file copied into the directory and RC extraction data saved. Writes files.
`saveDesign <final>.enc -tgz`	A single gzipped tar file, with library, SDC and other external files copied inside. Writes a file.
`saveDesign <final>.enc -no_wait <out_file>`	A save in a separate process while the session continues. Read the out file to see whether it completed.
`restoreDesign <final>.enc.dat <top>`	The saved design in memory. Do not edit the saved directory, because a modified one can corrupt the restore.

Netlist
`getExportMode`	Every setExportMode parameter with its value and whether the user set it.
`setExportMode -fullPinout true`	Makes saveNetlist write every pin of every instance, connected or not. Changes the session.
`saveNetlist <final>.v`	The logical Verilog netlist. Hierarchical only if the netlist loaded was hierarchical. Writes a file.
`saveNetlist <final_pg>.v -includePowerGround`	The netlist with physical-only PG nets and PG ports added, which some LVS flows prefer. Writes a file.
`saveNetlist <final>.v -replaceTieConnection`	1'b0 and 1'b1 constants replaced by undriven nets, for consumers that cannot read the constants. Writes a file.
`saveNetlist <final_phys>.v -includePhysicalCell {<cells>}`	The netlist with physical instances of the named cells. The reference says such a netlist should not be read back into Innovus. Writes a file.

DEF and floorplan files
`defOut -routing <final>.def`	A DEF file with floorplan, placed and unplaced standard cells and routing. Writes a file.
`defOut -floorplan -unplaced <final_fp>.def`	A DEF file with the floorplan and placed standard cells, and the unplaced standard cells. Writes a file.
`defOut -scanChain <final>.def`	A DEF file that also carries scan chain information, needed to keep the chain ends when the DEF is reloaded. Writes a file.
`defComp <final>.def -reportFile <f>`	The differences between a DEF file and the physical data in the database. Default report name is defPhyDiff.rpt.
`saveFPlan <final>.fp`	The floorplan information, including the placed, fixed and covered blocks, saved to a file. Writes a file.
`saveIoFile <final>.io`	The current I/O information saved to a file. Writes a file.

Stream files
`getStreamOutMode`	The current setStreamOutMode settings.
`setStreamOutMode -check_map_file true`	Makes streamOut check the map file: design objects that the map file does not map are listed in the log. Changes the session.
`streamOut <final>.gds -mapFile <map> -libName <lib> -units <n> -reportFile <f>`	A GDSII file of the whole database with all mapped layers. The report file receives the cell names that were changed. Writes files.
`streamOut <final>.gds -mapFile <map> -merge {<gds_files>}`	A GDSII file with the cell and macro stream files merged in, and a warning for every cell name that changed. Writes a file.
`streamOut <final>.oas -mapFile <map> -format oasis`	An OASIS file in place of GDSII. Writes a file.

Parasitics and delays
`rcOut -spef <final>.spef -rc_corner <corner>`	SPEF for the named RC corner. Writes a file.
`rcOut -spef <final>.spef -view <view>`	SPEF for the RC corner of the view. Views that share a corner give the same SPEF. Writes a file.
`writeTimingCon <final_view>.sdc -view <view>`	The timing constraints of the named view written in Design Compiler format. Writes a file.
`write_sdf <final>.sdf -recompute_delay_calc -min_view <view> -max_view <view>`	An SDF file with delays recomputed so that it is complete for general use, with min and max slots from the two views. Runs long and writes a file.

Block abstracts (only if the block is used inside a parent design)
`write_lef_abstract <block>.lef -noCutObs -stripePin -PGPinLayers <n> -specifyTopLayer <n>`	A LEF abstract of a routed block with one OBS per routing layer and PG pins on the top layer stripes. Writes a file.
`write_lef_library <lib>.lef`	The LEF library data present in the database, technology and macros. Writes a file.
`saveModel -dir <dir>`	Block-level LEF, DEF and database for top-level implementation. Timing library generation needs another command. Writes files.