allowedCutClass

Specifies whether a cut class on the given cut layer is allowed between shapes of certain widths. If lowerLayer and upperLayer are not specified, the viaDefs for the cut layer are used to determine the lower and upper layers. The lower and upper direction is determined by the wider dimension of the shape.

If all cut classes are allowed on all wire width combinations, the allowedCutClass constraint need not be defined.

allowedCutClass Quick Reference

Constraint Type	Layer
Value Types	`Value`
Database Types	Design, Technology
Scope	design, foundry
Category	Via Construction
Group Operators	AND, OR

Value Type

Int2DTblValue

Specifies whether a cut class on the given cut layer is allowed between shapes of certain widths. The column (-TblCols) and row headers for the 2-D table specify the widths of the shapes on the lower and upper layers, respectively. The value is set to 0 if the specified cut class is disallowed for the corresponding shape width combination, and 1 if allowed.

Required Parameter

cutClass

Specifies the cut class width and length.

Type: DualValue

Optional Parameters

`lowerLayer`	The metal layer below the cut layer. If not specified, the default stack is used to determine the lower metal layer. Type: `LayerValue`
`upperLayer`	The metal layer above the cut layer. If not specified, the default stack is used to determine the upper metal layer. Type: `LayerValue`
`lowerDirection`	The direction of the shape on the lower layer. The direction is determined by the wider dimension of the shape. The constraint applies if the shape has the specified direction. The values that can be specified for the lower direction are: `0`: `anyLowerDir` `1`: `horizontalLowerDir` `2`: `verticalLowerDir` Default is `0`, which means any lower direction. Type: `IntValue`
`upperDirection`	The direction of the shape on the upper layer. The direction is determined by the wider dimension of the shape. The constraint applies if the shape has the specified direction. The values that can be specified for the upper direction are: `0`: `anyUpperDir` `1`: `horizontalUpperDir` `2`: `verticalUpperDir` Default is `0`, which means any upper direction. Type: `IntValue`

Examples

set_constraint_parameter -name cutClass -DualValue {0.1 0.1}
set_constraint_parameter -name lowerLayer -LayerValue Metal1
set_constraint_parameter -name upperLayer -LayerValue Metal2
set_constraint_parameter -name lowerDirection -IntValue 1
set_constraint_parameter -name upperDirection -IntValue 1
set_layer_constraint -constraint allowedCutClass \
-layer Via1 -TblCols {0.1 0.2} -Int2DTblValue {0.1 1 0 0.2 0 1}

Specifies that a 0.1x0.1 cut class on layer Via1 is allowed between Metal1 and Metal2 wires only if both wires are greater than 0.1 or 0.2 user units in width and direction for both Metal1 and Metal2 wire is horizontal.

Virtuoso Space-based Router Constraint Reference
Product Version IC23.1, June 2023