Fine Control of Local Whitespace in Placement

Algorithm 1

Allocating whitespace in top-down placement to satisfy density constraints using uniform, minimum local, and safe whitespace allocation.

     ▷Input: placement bin 𝐵, whitespace target targetWS

     ▷Output: partitioned child bins

(1) SetTentativeCutline(𝐵)

(2) if (BinWhitespace(𝐵) >targetWS and targetWS ≥ SafeWS)

(3)  then SetPartToleranceSafe(𝐵, targetWS)

(4)   CallPartitioner(𝐵)

(5)   ShiftCutlineToMaintainTargetWS(𝐵, targetWS)

(6)  else if (BinWhitespace(𝐵) >targetWS

           and targetWS ≥ minLocalWS)

(7)     then SetPartToleranceMinLocal(𝐵, targetWS)

(8)      CallPartitioner(𝐵)

(9)      ShiftCutlineToMaintainTargetWS(𝐵, targetWS)

(10)     else SetPartToleranceUniform(𝐵)

(11)      CallPartitioner(𝐵)

(12)      ShiftCutlineToEqualizeWS(𝐵)

(13) FinalizeCutline(𝐵)

(14) CreateChildBins(𝐵)