Generate Layout Form

Use the Generate Layout form to generate a virtual hierarchy for the schematic instances that have no layout counterparts generated and to create soft blocks for schematic symbols that have no schematic or virtual hierarchy. For the virtual hierarchy generation options to be available on the Generate Layout form, you must have the Virtuoso Layout Suite EXL license checked out.

The Generate Layout form lets you specify the virtual hierarchy and area boundary generation options on the tabs below. For information on other layout generation options provided on the form, see Generate Layout.

Tab	Description
Generate	Lets you control if virtual hierarchies and soft blocks should be generated.
PR Boundary	Lets you specify the options to create the area boundary for a virtual hierarchy, the PR boundary for a soft block, or the top-level PR boundary. The Virtual Hierarchy Area Boundary options on the PR Boundary tab are enabled only when the Virtual Hierarchy option on the Generate tab is selected.

Tab

Description

Generate

Lets you control if virtual hierarchies and soft blocks should be generated.

PR Boundary

Lets you specify the options to create the area boundary for a virtual hierarchy, the PR boundary for a soft block, or the top-level PR boundary.

The Virtual Hierarchy Area Boundary options on the PR Boundary tab are enabled only when the Virtual Hierarchy option on the Generate tab is selected.

Generate

The following table describes the fields on the Generate tab of the Generate Layout form that support virtual hierarchy generation.

Field	Description
*Design Planning*	Specifies whether a virtual hierarchy is generated.
Virtual Hierarchy	Lets you generate a “yet-to-be-realized” hierarchy for the schematic instances that have no layout counterparts generated. Environment variable: generateVirtualHierarchy
Virtual Hierarchy Auto Generate Soft Blocks	Lets you generate soft blocks for the top-level virtual hierarchy blocks that have no schematic or layout available. Because there is no schematic available, soft block generation uses the bound symbol view to generate pins. Soft block boundary is generated using the options defined on the PR Boundary tab, ignoring the specified Utilization (%). Environment variable: generateSoftBlocks

Field

Description

Design Planning

Specifies whether a virtual hierarchy is generated.

Virtual Hierarchy

Lets you generate a “yet-to-be-realized” hierarchy for the schematic instances that have no layout counterparts generated.

Environment variable: generateVirtualHierarchy

Virtual Hierarchy Auto Generate Soft Blocks

Lets you generate soft blocks for the top-level virtual hierarchy blocks that have no schematic or layout available. Because there is no schematic available, soft block generation uses the bound symbol view to generate pins. Soft block boundary is generated using the options defined on the PR Boundary tab, ignoring the specified Utilization (%).

Environment variable: generateSoftBlocks

PR Boundary

The following table describes the fields on the PR Boundary tab of the Generate Layout form that support virtual hierarchy area boundary generation.

Field	Description
*Area Estimation*	This section lets you specify how the area of a virtual hierarchy or a soft block is estimated.
Area Estimate CSV File	Specifies the path to a CSV file containing soft block and virtual hierarchy sizes to use for estimating the area of the soft blocks and virtual hierarchies to be generated. Environment variable: areaEstimationCSVFile
*Virtual Hierarchy Area Boundary*	Specifies the options to generate the area boundary of a virtual hierarchy.
Enclose by	Specifies the distance from the objects inside the virtual hierarchy at which the area boundary is created.
Utilization (%)	Specifies the acceptable area utilization percentage for deriving the size of the area boundary for the virtual hierarchy. The utilization percentage also takes into account the size of each sub-virtual hierarchy to account for the additional space required. Environment variable: useAreaBoundaryUtilization When `useAreaBoundaryUtilization` is set to `nil`, the Enclose by option (areaBoundaryEnclosure) is used.
Top Level	Specifies that the selected area boundary settings be used for generating virtual hierarchy area boundaries only at the top level.
All Levels	Specifies that the selected area boundary settings be used for generating virtual hierarchy area boundaries at all levels in the virtual hierarchy of the top-level design.
None	Specifies that the virtual hierarchies for the design are generated without an area boundary. Environment variable: generateAreaBoundaries
*Soft Block*	Specifies the options to generate the area of a soft block.
Area	Specifies an estimated area value for the soft blocks to be generated. Environment variable: softBlockArea The value specified using the Area field is applied by default to all the soft blocks that are generated. To override this value and to customize the area of each generated soft block, you can specify a cellview property called `area` on the Symbol Generation Options form when creating a new symbol. Alternatively, you can update the property for an existing symbol using the Edit Cellview Properties form. In either case, a floating point value is specified for the `area` property.

Virtuoso Design Planning and Analysis User Guide
Product Version IC23.1, November 2023