allowedBoundaryDimensions

Specifies the allowed ranges for PR boundary and virtual hierarchy area boundary dimensions in the specified direction. You can optionally specify that the dimensions must be an exact multiple of a specified stepSize. These restrictions are required by certain methodologies to ensure that cells are placeable and flippable.

allowedBoundaryDimensions Quick Reference

Constraint Type	Simple
Value Types	`RangeArrayValue`
Database Types	Design, Technology
Scope	design, foundry
Category	Length and Width

Value Type

RangeArrayValue

Specifies the allowed ranges for the PR boundary dimensions.

Required Parameters

oaSpacingDirection

Specifies the measurement direction. The constraint applies only to dimensions measured in this direction.

Type: IntValue

0 any
1 horizontal
2 vertical

Optional Parameters

stepSize

Specifes legal dimensions for a PR boundaries measured in the specifies oaSpacingDirection.

The set of legal dimensions is computed as the lower bound (LB) of each range (inclusive) plus a multiple of the stepSize, up to the upper bound (UB) of the range if specified. Therefore, the dimension must be equal to LB + n*stepSize and <= UB.

If LB is not included in the range specification, the computation is still performed from LB, but the first value calculated (LB itself) is not considered a legal value. The first legal value would be LB + stepSize.

If the PR boundary is rectilinear, all dimensions in the given direction must meet the constraint. Specifically, the distance between facing edges perpendicular to spacing direction must meet the constraint. When multiple ranges are specified, stepSize applies to all ranges.

If stepSize is not specified, the PR boundary needs to fall into one of the specified ranges.

Type: FltValue

Examples

Specifies that the vertical distance between two facing edges must be greater than or equal to 0.24 and less than or equal to 4.8, and must be 0.24 plus a positive integer multiple of stepSize. In other words, it must be 0.24+n*0.048 and within the given range.

set_constraint_parameter -name oaSpacingDirection -IntValue 2
set_constraint_parameter -name stepSize -FltValue 0.048
set_constraint -constraint allowedBoundaryDimensions -RangeArrayValue {[0.24 4.8]}

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